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  1. Employees

Språkvelger

Norsk

Geir Johnsen

Geir Johnsen

Professor
Department of Biology

geir.johnsen@ntnu.no
+4773591581 +4791897027 Biologisk stasjon, 01.nov, Trondheim, Bynesveien 46
About Publications Teaching Media

About

CV

Geir Johnsen is a professor in marine biology at the Department of Biology (NTNU), Prof II at University Centre on Svalbard (UNIS), and is one of the founding partners in a NTNU spin-off company Ecotone using new optical techniques for mapping and monitoring the marine environment. He is a key scientist in the Centre of excellence (CeO) "Autonomous Marine Operations and Systems (AMOS). Currently he is on a 1 year research stay at University of Hawaii at Manoa, Honululu working with spectral bioluminescence in different taxa and mapping and monitoring of coral reefs.

Research areas

  • Marine ecology and biodiversity
  • Bio-optics
  • Photosynthesis
  • Pigment chemotaxonomy
  • Underwater robotics and sensor development for in situ identification
  • Mapping and monitoring of bio-geo-chemical objects of interest in the marine environment

He has been an adviser for 47 MSc students and 17 PhD candidates. Currently, he advises 3 MSc students and 5 PhD candidates.

He has published more than 130 papers in international scientific journals and been a co-editor for the books:

  • "Ecosystem Barents Sea" (Tapir Academic Press)
  • "Phytoplankton pigments: Updates on Characterization, Chemotaxonomy and Applications in Oceanography" (Cambridge University Press, 2011). 

Publications

  • Chronological
  • By category
  • See all publications in Cristin

2023

  • Bakken, Sivert; Henriksen, Marie Bøe; Birkeland, Roger; Langer, Dennis David; Oudijk, Adriënne Esmeralda; Berg, Simen. (2023) HYPSO-1 CubeSat: First Images and In-Orbit Characterization. Remote Sensing
    Academic article
  • Williamson, David Roddan; Moreira Fragoso, Glaucia; Majaneva, Sanna Kristiina; Dallolio, Alberto; Halvorsen, Daniel Ørnes; Hasler, Oliver Kevin. (2023) Monitoring Algal Blooms with Complementary Sensors on Multiple Spatial and Temporal Scales. Oceanography
    Academic article
  • Grant, Stephen Denis; Johnsen, Geir; McKee, David; Zolich, Artur Piotr; Cohen, Jonathan H.. (2023) Spectral and RGB analysis of the light climate and its ecological impacts using an all-sky camera system in the Arctic. Applied Optics
    Academic article
  • Summers, Natalie Maria; Moreira Fragoso, Glaucia; Johnsen, Geir. (2023) Photophysiologically active green, red, and brown macroalgae living in the Arctic Polar Night. Scientific Reports
    Academic article
  • Schartmuller, Bernhard; Anderson, Philip; Mckee, David; Connan-McGinty, Stacey; Kopec, Tomasz Piotr; Daase, Malin Hildegard Elisabeth. (2023) Development and calibration of a high dynamic range and autonomous ocean-light instrument to measure sub-surface profiles in ice-covered waters. Applied Optics
    Academic article
  • Gerland, Sebastian; Ingvaldsen, Randi Brunvær; Reigstad, Marit; Sundfjord, Arild; Bogstad, Bjarte; Chierici, Melissa. (2023) Still Arctic? — The changing Barents Sea. Elementa: Science of the Anthropocene
    Academic literature review

2022

  • Nøland, Annecken; Johnsen, Geir; Aberle-Malzahn, Nicole. (2022) Autonomous Underwater Vehicle (AUV) based study of zooplankton communities, using a silhouette camera and artificial intelligence. NTNU
    Masters thesis
  • Johnsen, Geir; Aberle-Malzahn, Nicole; Fragoso, Glaucia; Thu, Maren. (2022) Phytoplankton Spring Bloom Mapping in Coastal Areas Using Autonomous Underwater Vehicle (AUV) and Optical Approaches. NTNU
    Masters thesis
  • Zolich, Artur Piotr; Faltynkova, Andrea; Johnsen, Geir; Johansen, Tor Arne. (2022) Portable Catamaran Drone - an uncrewed sampling vehicle for micro-plastics and aquaculture research.
    Academic chapter/article/Conference paper
  • Summers, Natalie; Johnsen, Geir; Mogstad, Aksel Alstad; Løvås, Håvard; Fragoso, Glaucia Moreira; Berge, Jørgen. (2022) Underwater Hyperspectral Imaging of Arctic Macroalgal Habitats during the Polar Night Using a Novel Mini-ROV-UHI Portable System. Remote Sensing
    Academic article
  • Fragoso, Glaucia Moreira; Davies, Emlyn John; Fossum, Trygve Olav; Ullgren, Jenny; Majaneva, Sanna; Aberle-Malzahn, Nicole. (2022) Contrasting phytoplankton-zooplankton distributions observed through autonomous platforms, in-situ optical sensors and discrete sampling. PLOS ONE
    Academic article
  • Mogstad, Aksel Alstad; Løvås, Håvard; Sture, Øystein; Johnsen, Geir; Ludvigsen, Martin. (2022) Remote Sensing of the Tautra Ridge: An Overview of the World’s Shallowest Cold-Water Coral Reefs. Frontiers in Marine Science
    Academic article
  • Nevstad, Malin Bø; Johnsen, Geir; Bakken, Torkild; Larsen, Martin Kvisvik; Mogstad, Aksel Alstad. (2022) Use of different imaging systems for ROV-based mapping of complex benthic habitats. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Marnor, Camilla Mult; Johnsen, Geir; Bakken, Torkild; Mogstad, Aksel Alstad. (2022) Mapping distribution patterns of brittle stars using ROV-based imaging. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Bjerkvoll, Mikkel; Johnsen, Geir; Bakken, Torkild; Mogstad, Aksel Alstad. (2022) Aerial and underwater hyperspectral imagery for shallow benthic nature type mapping. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Søreng, Marte Opsahl; Johnsen, Geir; Bakken, Torkild; Mogstad, Aksel Alstad; Gryte, Kristoffer. (2022) Mapping of Zostera Habitat in the Sublittoral Zone using Underwater Hyperspectral Imaging and Unmanned Surface Vehicle. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Connan-McGinty, Stacey; Banas, Neil S.; Berge, Jørgen; Cottier, Finlo Robert; Grant, Stephen; Johnsen, Geir. (2022) Midnight Sun to Polar Night: A Model of Seasonal Light in the Barents Sea. Journal of Advances in Modeling Earth Systems
    Academic article
  • Oudijk, Esmée; Hasler, Oliver Kevin; Øveraas, Henning; Marty, Sabine; Williamson, David Roddan; Svendsen, Torbjørn Karl. (2022) Campaign For Hyperspectral Data Validation In North Atlantic Coastal Waters. Workshop on Hyperspectral Image and Signal Processing, Evolution in Remote Sensing
    Academic article
  • Dona, Angela; Evertsen, Jussi; Johnsen, Geir. (2022) The role of parapodia and lack of photoacclimation in kleptoplasts of the sacoglossan sea slug Plakobranchus ocellatus. Coral reefs
    Academic article

2021

  • Cohen, Jonathan H.; Last, Kim; Charpentier, Corie L.; Cottier, Finlo; Daase, Malin; Hobbs, Laura. (2021) Photophysiological cycles in Arctic krill are entrained by weak midday twilight during the Polar Night. PLoS Biology
    Academic article
  • Cardwell, CR; Berge, Jørgen; Johnsen, Geir. (2021) Arctic voyage shines light on some cold, hard truths. The Herald, UK
    Popular scientific article
  • Bazilchuk, Nancy Reney; Berge, Jørgen; Johnsen, Geir. (2021) Lysforurensning I Arktis kan ha ødelagt forskningsresultater. Gemini.no
    Popular scientific article
  • Berge, Jørgen; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Johnsen, Geir. (2021) Time series (2019) of irradiance in the PAR (photosynthetically active radiation) region measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway) derived from an USSIMO spectroradiometer.
    Other product
  • Berge, Jørgen; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Johnsen, Geir. (2021) Time series (2018) of irradiance in the PAR (photosynthetically active radiation) region measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway) derived from an USSIMO spectroradiometer. .
    Other product
  • Berge, Jørgen; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Johnsen, Geir. (2021) USSIMO spectroradiometer raw data time series (2019) measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway).
    Other product
  • Berge, Jørgen; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Johnsen, Geir. (2021) USSIMO spectroradiometer raw data time series (2020) measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway).
    Other product
  • Johnsen, Geir; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Kopec, Tomasz Piotr. (2021) Pictures from an all-sky camera with hourly resolution from the light observatory at Ny-Ålesund, Svalbard, Norway (complete year 2017).
    Other product
  • Johnsen, Geir; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Kopec, Tomasz Piotr. (2021) Time series (2018) of irradiance in the PAR (photosynthetically active radiation) region measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway) derived from SLR camera.
    Other product
  • Johnsen, Geir; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Kopec, Tomasz Piotr. (2021) Time series (2020) of irradiance in the PAR (photosynthetically active radiation) region measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway) derived from SLR camera.
    Other product
  • Johnsen, Geir; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Kopec, Tomasz Piotr. (2021) Time series (2019) of irradiance in the PAR (photosynthetically active radiation) region measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway) derived from SLR camera.
    Other product
  • Ringvold, Halldis; Taite, Morag; Allcock, A. Louise; Vecchione, Michael; Péan, Michel; Sandulli, Roberto. (2021) In situ recordings of large gelatinous spheres from NE Atlantic, and the first genetic confirmation of egg mass of Illex coindetii (Vérany, 1839) (Cephalopoda, Mollusca). Scientific Reports
    Academic article
  • Bakken, Sivert; Johnsen, Geir; Johansen, Tor Arne. (2021) Analysis and Model Development of Direct Hyperspectral Chlorophyll-A Estimation for Remote Sensing Satellites. Workshop on Hyperspectral Image and Signal Processing, Evolution in Remote Sensing
    Academic article
  • Horni, K; Sørensen, Asgeir Johan; Johnsen, Geir; Ludvigsen, Martin. (2021) Internasjonalt forskningsmiljø dykker i Mjøsa etter at Oppland Arbeiderblad skrev om forurensning. Oppland arbeiderblad
    Popular scientific article
  • Bazilchuk, Nancy Reney; Stahl, Annette; Johnsen, Geir; Saad, Aya; Thu, Maren; Nøland, Annecken. (2021) Sporhunden som lukter mikroalger. . Gemini.no
    Popular scientific article
  • Ringvold, Halldis; Johnsen, Geir; Andersen, Tom. (2021) Studies on Echinodermata from the NE Atlantic Ocean - Spatial distribution and abundance of Asteroidea, including taxonomic and molecular studies on Crossaster and Henricia genera - Value-chain results, including test fishery, biology, market and nutritional analysis on Parastichopus tremulus (Holothuroidea) from the Norwegian coast. Doktoravhandlinger ved NTNU (2021-254)
    Doctoral dissertation
  • Mogstad, Aksel Alstad; Johnsen, Geir; Sørensen, Asgeir Johan; Ludvigsen, Martin. (2021) Underwater hyperspectral imaging as a tool for benthic habitat mapping. Doktoravhandlinger ved NTNU (2021/271)
    Doctoral dissertation
  • Snyder, Mike; Berge, Jørgen; Johnsen, Geir; Mckee, David. (2021) “Into the dark” documentary by Mike Snyder following Jørgen Berge (UiT), Geir Johnsen (NTNU) and David McKee (Uni Strathclyde) during Polar Night marine ecology work. .
    Film
  • Johnsen, Geir; Zolich, Artur; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan H.; Mckee, David. (2021) All-sky camera system providing high temporal resolution annual time series of irradiance in the arctic. Applied Optics
    Academic article
  • Geoffroy, Maxime; Langbehn, Tom Jasper; Priou, Pierre; Varpe, Øystein; Johnsen, Geir; Le Bris, Arnault. (2021) Pelagic organisms avoid white, blue, and red artificial light from scientific instruments. Scientific Reports
    Academic article
  • Johnsen, Geir; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Kopec, Tomasz Piotr. (2021) Pictures from an all-sky camera with hourly resolution from the light observatory at Ny-Ålesund, Svalbard, Norway (complete year 2019).
    Other product
  • Løvås, Håvard; Mogstad, Aksel Alstad; Sørensen, Asgeir Johan; Johnsen, Geir. (2021) A Methodology for Consistent Georegistration in Underwater Hyperspectral Imaging. IEEE Journal of Oceanic Engineering
    Academic article
  • Johnsen, Geir; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Kopec, Tomasz Piotr. (2021) Pictures from an all-sky camera with hourly resolution from the light observatory at Ny-Ålesund, Svalbard, Norway (complete year 2018).
    Other product
  • Johnsen, Geir; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Kopec, Tomasz Piotr. (2021) Pictures from an all-sky camera with hourly resolution from the light observatory at Ny-Ålesund, Svalbard, Norway (complete year 2020).
    Other product
  • Berge, Jørgen; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Johnsen, Geir. (2021) USSIMO spectroradiometer raw data time series (2017) measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway) .
    Other product
  • Johnsen, Geir; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Kopec, Tomasz Piotr. (2021) Photosynthetic active radiation (PAR) time series measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway).
    Other product
  • Berge, Jørgen; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Johnsen, Geir. (2021) Time series (2017) of irradiance in the PAR (photosynthetically active radiation) region measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway) derived from an USSIMO spectroradiometer.
    Other product
  • Berge, Jørgen; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Johnsen, Geir. (2021) Time series (2020) of irradiance in the PAR (photosynthetically active radiation) region measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway) derived from an USSIMO spectroradiometer.
    Other product
  • Berge, Jørgen; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Johnsen, Geir. (2021) USSIMO spectroradiometer raw data time series (2018) measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway).
    Other product
  • Johnsen, Geir; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan; Mckee, David; Kopec, Tomasz Piotr. (2021) Time series (2017) of irradiance in the PAR (photosynthetically active radiation) region measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway) derived from SLR camera.
    Other product
  • Faltynkova, Andrea; Johnsen, Geir; Wagner, Martin. (2021) Hyperspectral imaging as an emerging tool to analyze microplastics: A systematic review and recommendations for future development. Microplastics and Nanoplastics
    Academic literature review

2020

  • Ramirez-Llodra, Eva; Hilário, Ana; Paulsen, Emil; Costa, Carolina; Bakken, Torkild; Johnsen, Geir. (2020) Benthic Communities on the Mohn’s Treasure Mound: Implications for Management of Seabed Mining in the Arctic Mid-Ocean Ridge. Frontiers in Marine Science
    Academic article
  • Berge, Jørgen; Johnsen, Geir. (2020) Life and Light at the Dead of Night. Springer
    Academic chapter/article/Conference paper
  • Cohen, Jonathan H.; Berge, Jørgen; Moline, Mark A.; Johnsen, Geir; Zolich, Artur Piotr. (2020) Light in the Polar Night. Springer
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Mogstad, Aksel Alstad; Berge, Jørgen; Cohen, Jonathan H.. (2020) Operative Habitat Mapping and Monitoring in the Polar Night. Springer
    Academic chapter/article/Conference paper
  • Berge, Jørgen; Johnsen, Geir. (2020) • Polar Night Exhibitions in Russia 2020. Kaliningrad – World Ocean Museum.
    Museum exhibition
  • Gibbens, Sarah; Berge, Jørgen; Johnsen, Geir; Mckee, David. (2020) As the Arctic warms, light pollution may pose a new treat to marine life. . National Geographic
    Interview Journal
  • Johnsen, Geir; Leu, Eva; Gradinger, Rolf. (2020) Marine Micro- and Macroalgae in the Polar Night. Springer
    Academic chapter/article/Conference paper
  • Berge, Jørgen; Geoffroy, Maxime; Daase, Malin; Cottier, Finlo Robert; Priou, Pierre; Cohen, Jonathan H.. (2020) Artificial light during the polar night disrupts Arctic fish and zooplankton behavior down to 200 m depth. Communications Biology
    Academic article
  • Berge, Jørgen; Johnsen, Geir; Cohen, Jonathan H.. (2020) Polar night marine ecology - life and light in the dead of night. Springer Advances in Polar Ecology (0)
    Academic anthology/Conference proceedings
  • Berge, Jørgen; Johnsen, Geir. (2020) Polar Night exhibition in Karelia (Petrozavodsk, Russia): 03.03 – 03.04.2020 . Polar Night exhibition, Karelia (Petrozavodsk, Russia). March-April 2020
    Museum exhibition
  • Saad, Aya; Stahl, Annette; Våge, Andreas; Davies, Emlyn John; Nordam, Tor; Aberle-Malzahn, Nicole. (2020) Advancing Ocean Observation with an AI-driven Mobile Robotic Explorer. Oceanography
    Academic article
  • Berge, Jørgen; Johnsen, Geir; Cohen, Jonathan H.. (2020) Introduction. Springer
    Introduction
  • Fragoso, Glaucia Moreira; Johnsen, Geir; Chauton, Matilde Skogen; Cottier, Finlo Robert; Ellingsen, Ingrid H.. (2020) Phytoplankton community succession and dynamics using optical approaches. Continental Shelf Research
    Academic article
  • Mogstad, Aksel Alstad; Ødegård, Øyvind; Nornes, Stein Melvær; Ludvigsen, Martin; Johnsen, Geir; Sørensen, Asgeir Johan. (2020) Mapping the Historical Shipwreck Figaro in the High Arctic Using Underwater Sensor-Carrying Robots. Remote Sensing
    Academic article

2019

  • Fragoso, Glaucia Moreira; Davies, Emlyn John; Ellingsen, Ingrid H.; Chauton, Matilde Skogen; Fossum, Trygve Olav; Ludvigsen, Martin. (2019) Physical controls on phytoplankton size structure, photophysiology and suspended particles in a Norwegian biological hotspot. Progress in Oceanography
    Academic article
  • Kleiven, Wanda; Johnsen, Geir; Ardelan, Murat Van. (2019) Sea surface microlayer and elemental composition in phaeo-, chloro-, and rhodophytes in winter and spring. Journal of Phycology
    Academic article
  • Graham, Lisa Kristine Hernandez; Johnsen, Geir; Christensen-Dalsgaard, Signe. (2019) A pilot study assessing drones for mapping and monitoring of European shags. Institutt for biologi, NTNU
    Masters thesis
  • Mogstad, Aksel Alstad; Johnsen, Geir; Ludvigsen, Martin. (2019) Shallow-Water Habitat Mapping using Underwater Hyperspectral Imaging from an Unmanned Surface Vehicle: A Pilot Study. Remote Sensing
    Academic article
  • Kauko, Hanna Maria; Pavlov, Alexey; Johnsen, Geir; Granskog, Mats; Peeken, Ilka; Assmy, Philipp. (2019) Photoacclimation state of an Arctic underice phytoplankton bloom. Journal of Geophysical Research (JGR): Oceans
    Academic article
  • Pavlov, Alexey K.; Leu, Eva; Hanelt, Dieter; Bartsch, Inka; Karsten, Ulf; Hudson, Stephen. (2019) The Underwater Light Climate in Kongsfjorden and Its Ecological Implications. Springer
    Academic chapter/article/Conference paper
  • Bazilchuk, Nancy Reney; Fossum, Trygve Olav; Fragoso, Glaucia Moreira; Ludvigsen, Martin; Johnsen, Geir. (2019) Smart undervannsrobot leter etter plankton. Av N Bazilchuk. Forskning.no. Angående NTNU Entice prosjekt publisert i Science Robotics. Forskning.no
    Popular scientific article
  • Fossum, Trygve Olav; Fragoso, Glaucia Moreira; Davies, Emlyn John; Ullgren, Jenny; Mendes, Renato; Johnsen, Geir. (2019) Toward adaptive robotic sampling of phytoplankton in the coastal ocean. Science robotics
    Academic article
  • Fragoso, Glaucia Moreira; Poulton, Alex James; Pratt, Nicola Jane; Johnsen, Geir; Purdie, Duncan Alastair. (2019) Trait-based analysis of subpolar North Atlantic phytoplankton and plastidic ciliate communities using automated flow cytometer. Limnology and Oceanography
    Academic article

2018

  • Fragoso, Glaucia Moreira; Poulton, Alex J.; Yashayaev, Igor M.; Head, Erica J.H.; Johnsen, Geir; Purdie, Duncan A.. (2018) Diatom biogeography from the Labrador Sea revealed through a trait-based approach. Frontiers in Marine Science
    Academic article
  • Dumke, Ines; Nornes, Stein Melvær; Purser, Autun; Marcon, Yann; Ludvigsen, Martin; Ellefmo, Steinar Løve. (2018) First hyperspectral imaging survey of the deep seafloor: High-resolution mapping of manganese nodules. Remote Sensing of Environment
    Academic article
  • Zolich, Artur Piotr; De La Torre, Pedro R.; Rodwell, Shane; Geoffroy, Maxime; Johnsen, Geir; Berge, Jørgen. (2018) An ice-tethered buoy for fish and plankton research. IEEE conference proceedings
    Academic chapter/article/Conference paper
  • Fjærtoft, Kaja Lønne; Bakken, Torkild; Johnsen, Geir; Ludvigsen, Martin. (2018) Macroalgal detritus: Physical variables and impacts on the benthic macrofaunal community. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Ødegård, Øyvind; Sørensen, Asgeir Johan; Johnsen, Geir; Ludvigsen, Martin; Hansen, Roy Edgar; Maarleveld, Thijs. (2018) Towards Autonomous Operations and Systems in Marine Archaeology. Doktoravhandlinger ved NTNU (IMT-12)
    Doctoral dissertation
  • Strømsholm, Jørgen; Johnsen, Geir; Ludvigsen, Martin. (2018) Eyes beneath the surface - using a miniROV to reveal habitat and dietary choices of the European shag. NTNU MSc thesis
    Masters thesis
  • Kauko, Hanna Maria; Johnsen, Geir; Assmy, Phillipp. (2018) Light response and acclimation of macroalgae in a changing Arctic. Doktoravhandlinger ved NTNU (2018)
    Doctoral dissertation
  • Berge, Jørgen; Johnsen, Geir. (2018) Lysforurensning - enda en kilde til bekymring. Svalbardposten
    Feature article
  • Berge, Jørgen; Johnsen, Geir. (2018) Lysforurensning truer livet i Arktis. Aftenposten Viten
    Feature article
  • Ludvigsen, Martin; Berge, Jørgen; Geoffroy, Maxime; Cohen, Jonathan H.; De La Torre, Pedro R.; Nornes, Stein Melvær. (2018) Use of an autonomous surface vehicle reveals small-scale diel vertical migrations of zooplankton and susceptibility to light pollution under low solar irradiance. Science Advances
    Academic article
  • Nornes, Stein Melvær; Sørensen, Asgeir Johan; Ludvigsen, Martin; Johnsen, Geir; Schjølberg, Ingrid; Ånonsen, Kjetil Bergh. (2018) Guidance and Control of Marine Robotics for Ocean Mapping and Monitoring. Doktoravhandlinger ved NTNU (2018:202)
    Doctoral dissertation
  • Ødegård, Øyvind; Mogstad, Aksel Alstad; Johnsen, Geir; Sørensen, Asgeir Johan; Ludvigsen, Martin. (2018) Underwater hyperspectral imaging: a new tool for marine archaeology. Applied Optics
    Academic article
  • Fossum, Trygve Olav; Eidsvik, Jo; Ellingsen, Ingrid H.; Alver, Morten; Fragoso, Glaucia Moreira; Johnsen, Geir. (2018) Information-driven robotic sampling in the coastal ocean. Journal of Field Robotics (JFR)
    Academic article
  • Kauko, Hanna Maria; Olsen, Lasse Mork; Duarte, Pedro; Peeken, Ilka; Granskog, Mats A.; Johnsen, Geir. (2018) Algal colonization of young arctic sea ice in spring. Frontiers in Marine Science
    Academic article
  • Dumke, Ines; Purser, Autun; Marcon, Yann; Nornes, Stein Melvær; Johnsen, Geir; Ludvigsen, Martin. (2018) Underwater hyperspectral imaging as an in situ taxonomic tool for deep-sea megafauna. Scientific Reports
    Academic article
  • Liefmann, Stephanie; Järnegren, Johanna; Johnsen, Geir; Murray, Fiona. (2018) Eco-physiological responses of cold-water soft corals to anthropogenic sedimentation and particle shape. Journal of Experimental Marine Biology and Ecology
    Academic article
  • Geoffroy, Maxime; Berge, Jørgen; Majaneva, Sanna Kristiina; Johnsen, Geir; Langbehn, Tom; Cottier, Finlo Robert. (2018) Increased occurrence of the jellyfish Periphylla periphylla in the European high Arctic. Polar Biology
    Short communication
  • Johnsen, Geir; Norli, Marit; Moline, Mark A.; Robbins, Ian; Quillfeldt, Cecilie von; Sørensen, Kai. (2018) The advective origin of an under-ice spring bloom in the Arctic Ocean using multiple observational platforms. Polar Biology
    Academic article
  • Dumke, Ines; Ludvigsen, Martin; Ellefmo, Steinar Løve; Søreide, Fredrik; Johnsen, Geir; Murton, Bramley J.. (2018) Underwater Hyperspectral Imaging Using a Stationary Platform in the Trans-Atlantic Geotraverse Hydrothermal Field. IEEE Transactions on Geoscience and Remote Sensing
    Academic article
  • Gabrielsen, Tove M.; Johnsen, Geir. (2018) Skogen på Svalbard. Svalbardposten
    Popular scientific article

2017

  • Berge, Jørgen; Johnsen, Geir; Tandberg, Anne helene. (2017) Polar night - Life and light in the dead of night. Russian Science Week - Lomonosov Moscow State University
    Museum exhibition
  • Otterlei, Inger; Johnsen, Geir; Sørensen, Asgeir Johan; Ludvigsen, Martin; Hareide, Nils Roar; Christensen-Dalsgaard, Signe. (2017) 300 000 sjøfugl er forsvunnet fra Runde. Sunnmørsposten
    Interview Journal
  • Mynors, Julie; Johnsen, Geir; Wernand, Marcel; Volent, Zsolt. (2017) Ocean Colour and Phytoplankton Dynamics - An examination of the Forel-Ule scale in a modern context. NTNU Trondheim
    Masters thesis
  • Johnsen, Geir; Christiansen, Hanne H; Ravolainen, Virve; Reymert, Per Kyrre; Jenssen, Eva Therese; Arlov, Thor Bjørn. (2017) Utfordrende natur og sikkerhet på Svalbard. Svalbardposten
    Feature article
  • Kamilla, Sporsheim; Sporsheim, Kamilla; Johnsen, Geir; Reitan, Kjell Inge; Evertsen, Antii Jussi. (2017) Astaxanthin as a biomarker for fish feed loading in the marine ecosystem. NTNU, Trondheim
    Masters thesis
  • Kjeken, John; Johnsen, Geir; Ludvigsen, Martin; Thorsnes, Terje; Lågstad, Petter Arthur. (2017) The growth of benthic organisms in a dumping ground for military bombs and munitions. NTNU, Trondheim
    Masters thesis
  • Johnsen, Geir; Sandbu, Marthe; Assmy, Philipp. (2017) High Arctic Sea-Ice Algae: The Use of Rapid Light Curves to Assess Photosynthetic Performance of Different Ice-Algal Communities. Master science NTNU
    Masters thesis
  • Ostaszewska, Kaja; Balazy, Piotr; Berge, Jørgen; Johnsen, Geir; Staven, Robert. (2017) Seabirds during Arctic Polar Night: underwater observations from Svalbard archipelago, Norway. Waterbirds (De Leon Springs, Fla.)
    Academic article
  • Kauko, Hanna Maria; Taskjelle, Torbjørn; Assmy, Philipp; Pavlov, Alexey K.; Mundy, C.J.; Duarte, Pedro. (2017) Windows in Arctic sea ice: light transmission and ice algae in a refrozen lead. Journal of Geophysical Research (JGR): Biogeosciences
    Academic article
  • Berge, Jørgen; Johnsen, Geir. (2017) Kunnskapshull om livet i Arktis i mørketiden. Aftenposten Viten
    Feature article
  • Assmy, Philipp; Fernández-Méndez, Mar; Duarte, Pedro; Meyer, Amelie; Randelhoff, Achim; Mundy, Christopher John. (2017) Leads in Arctic pack ice enable early phytoplankton blooms below snow-covered sea ic. Scientific Reports
    Academic article
  • Mogstad, Aksel Alstad; Johnsen, Geir. (2017) Spectral characteristics of coralline algae: a multi-instrumental approach, with emphasis on underwater hyperspectral imaging. Applied Optics
    Academic article
  • Berge, Jørgen; Johnsen, Geir. (2017) Om bambus, spøkelseskreps og et Arktis i endring. Svalbardposten
    Feature article
  • Berge, Jørgen; Johnsen, Geir. (2017) Superkommunisten. Svalbardposten
    Feature article
  • Andersson, Ingvild Henriette Kristin; Johnsen, Geir; Bakken, Torkild; Ludvigsen, Martin. (2017) Bio-optical diversity on cold water coral habitats. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Alvsvåg, Dora Marie; Johnsen, Geir; Bakken, Torkild; Ludvigsen, Martin; Berge, Jørgen. (2017) Mapping of a seagrass habitat in Hopavågen, Sør-Trøndelag, with the use of an Autonomous Surface Vehicle combined with optical techniques. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Paulsen, Emil; Bakken, Torkild; Ramirez-Llodra, Eva; Johnsen, Geir. (2017) Community structure and biodiversity of the benthic megafauna at the inactive hydrothermal site Mohn's Treasure, on the Mohn's Ridge, Arctic Mid-Ocean Ridge (AMOR) . Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis

2016

  • Berge, Jørgen; Ødegård, Øyvind; Johnsen, Geir. (2016) Opp fra polarnattens mørke. Aftenposten Viten
    Feature article
  • Berge, Jørgen; Ødegård, Øyvind; Johnsen, Geir. (2016) A bitter-sweet symphony. Svalbardposten
    Feature article
  • Gätzschmann, Per; Hårsaker, Karstein; Johnsen, Geir; Leite, Stein Roar; Pedersen, Solbjørg; Sørumgård, Marit. (2016) Nye oppdagelser i polarnatta - video. Polarnatt
    Museum exhibition
  • Berge, Jørgen; Geoffroy, Maxime; Johnsen, Geir; Cottier, Finlo Robert; Bluhm, Bodil; Vogedes, Daniel Ludwig. (2016) Ice-tethered observational platforms in the Arctic Ocean pack ice. IFAC-PapersOnLine
    Academic article
  • Cronin, Heather; Cohen, Jonathan H.; Berge, Jørgen; Johnsen, Geir; Moline, Mark A.. (2016) Bioluminescence as an ecological factor during high Arctic polar night. Scientific Reports
    Academic article
  • Berge, Jørgen; Johnsen, Geir; Ludvigsen, Martin; Cohen, Jonathan. (2016) Design for latskap - men med store muligheter. Svalbardposten
    Feature article
  • Jakobsen, June; Johnsen, Geir; Bakken, Torkild; Ludvigsen, Martin; Karlsen, Svein. (2016) The Tautra Cold-Water Coral Reef - Mapping and describing the biodiversity of a cold-water coral reef ecosystem in the Trondheimsfjord by use of multi-beam echo sounding and video mounted on a remotely operated vehicle. NTNU
    Masters thesis
  • Bondø, Tor-Hartvig; Johnsen, Geir; Berge, Jørgen. (2016) Fant yrende liv i polarnatta. VG : Verdens gang
    Popular scientific article
  • Berge, Jørgen; Johnsen, Geir. (2016) Mørkets fyrster med påskrudd lys. Svalbardposten
    Popular scientific article
  • Bazilchuk, Nancy Reney; Leite, Stein Roar; Johnsen, Geir; Kjeken, John; Sørensen, Asgeir Johan; Ludvigsen, Martin. (2016) Bomber og buss på havbunnen. Gemini
    Popular scientific article
  • Haudemann-Andersen, Jørn; Lystad, M S; Johnsen, Geir; Sørensen, Asgeir Johan; Berge, Jørgen. (2016) Blå lys i det kalde dyp. NRK Trøndelag, Nyheter
    Popular scientific article
  • Haugstad, Tor; Erdal, Ivar; Johnsen, Geir; Sørensen, Asgeir Johan; Fjærvik, Nils. (2016) Gründerne mener dette kameraet kan bli det nye ekkoloddet – Ecotone er kandidat til TU Tech Award. Teknisk Ukeblad
    Popular scientific article
  • Bjørgan, Espen Halvorsen; Johnsen, Geir; Kjeken, Jon; Ludvigsen, Martin. (2016) Fant buss på 600 m dybde. Adresseavisen
    Popular scientific article
  • Håpnes, Sverre Julian; Johnsen, Geir; Ludvigsen, Martin; Lågstad, Petter Arthur. (2016) Mapping of demersal fish and benthos by AUV equipped with optical and acoustic imagers at 600 m depth in Trondheimsfjorden. NTNU MSc
    Masters thesis
  • Liefmann, Stephanie; Johnsen, Geir; Järnegren, Johanna. (2016) Eco-physiological responses of cold-water corals to anthropogenic sedimentation and particle shape. NTNU Mastergrad
    Masters thesis
  • Johnsen, Geir; Berge, Jørgen; Sørensen, Asgeir Johan; Sørumgård, Marit; Sandbakk, Elin; Johnsen, Tobias Kvendseth. (2016) Polarnatt/Polar Night - ny utstilling med nyheter fra 2015-2016. Polarnattsutstilling ved Vitenskapsmuseet NTNU
    Museum exhibition
  • Johnsen, Geir; Ludvigsen, Martin; Sørensen, Asgeir Johan; Aas, Lars Martin Sandvik. (2016) The use of underwater hyperspectral imaging deployed on remotely operated vehicle – methods and applications. IFAC-PapersOnLine
    Academic article
  • Berge, Jørgen; Johnsen, Geir; Ødegård, Øyvind. (2016) Kinderegg i polarnatten. Svalbardposten
    Feature article
  • Donahue, Michelle; Berge, Jørgen; Johnsen, Geir; Ødegård, Øyvind. (2016) The age of humans - living in the anthropocene - "Termites of the sea" found munching wood near Arctic shipwrecks. Smithsonian
    Popular scientific article
  • Bazilchuk, Nancy Reney; Johnsen, Geir; Berge, Jørgen; Sørensen, Asgeir Johan; Ødegård, Øyvind. (2016) Dark lords, werewolves and Indiana Jones in the polar night. Gemini (English edition)
    Interview Journal
  • Krüger, Frida Jørstad; Johnsen, Geir; Kjeken, John; Ludvigsen, Martin. (2016) Gammel buss ble korallrev. NRK Viten
    Popular scientific article
  • Kokkegård, Hanne; Johnsen, Geir; Ludvigsen, Martin; Torre, Pedro De La. (2016) Vitenskab - Bomber fra 2 verdenskrig danner koralrev på 600 m dybde. Danmarks radio
    Popular scientific article
  • Haugstad, Tormod; Erdal, Ivar; Johnsen, Geir. (2016) Kameraet deres «kan bli det nye ekkoloddet». Nå er det norske selskapet i ferd med å lykkes. Teknisk Ukeblad
    Interview Journal
  • Johnsen, Geir. (2016) Yrende liv i Isfjorden. Svalbardposten
    Popular scientific article
  • Aarskog, Karine Nigar; Berge, Jørgen; Johnsen, Geir; Sørensen, Asgeir Johan. (2016) Et stort løft for arktisk forskning (NTNU & UiT). Universitetet i Tromsø
    Article in business/trade/industry journal
  • Berge, Jørgen; Falk-Petersen, Stig; Renaud, Paul E.; Daase, Malin; Geoffroy, Maxime; Johnsen, Geir. (2016) En reise mot Ultima Thule. Svalbardposten
    Popular scientific article
  • Lervik, Frank; Johnsen, Geir; Ludvigsen, Martin; Kjeken, John. (2016) Det ligger flere busser der. Adresseavisen
    Popular scientific article
  • Berge, Jørgen; Johnsen, Geir; Ødegård, Øyvind. (2016) Mark spiser opp vrak på havbunnen. Fiskaren
    Popular scientific article
  • Kintisch, Eli; Berge, Jørgen; Last, Kim; Cohen, Jonathan; Johnsen, Geir. (2016) Voyage into darkness . Science
    Interview Journal
  • Bazilchuk, Nancy Reney; Johnsen, Geir; Berge, Jørgen; Ludvigsen, Martin; Sørensen, Asgeir Johan; Ødegård, Øyvind. (2016) Mørkets fyrster, varulver og Indiana Jones. Gemini
    Popular scientific article
  • Berge, Jørgen; Renaud, Paul E.; Johnsen, Geir; Darnis, Gerald; Geoffroy, Maxime; Daase, Malin. (2016) I grenselandet (mellom Tull og Thule). Svalbardposten
    Popular scientific article
  • Førde, Henny; Forbord, Silje; Handå, Aleksander; Fossberg, Julia; Arff, Johanne; Johnsen, Geir. (2016) Development of bryozoan fouling on cultivated kelp (Saccharina latissima) in Norway. Journal of Applied Phycology
    Academic article

2015

  • Nilssen, Ingunn; Dos Santos, Francisco; Coutinho, Ricardo; Gomes, Natalia; Cabral, Marcelo M.; Eide, Ingvar. (2015) Assessing the potential impact of water-based drill cuttings on deep water calcareous red algae using species specific impact categories and measured oceanographic and discharge data. Marine Environmental Research
    Academic article
  • Nilssen, Ingunn; Santos dos, Francisco; Coutinho, Ricardo; Gomes, Natalia; Cabral Montenegro, Marcelo; Eide, Ingvar. (2015) Assessing the potential impact of water-based drill cuttings on deep-water calcareous red algae using species specific impact categories and measured oceanographic and discharge data. Marine Environmental Research
    Academic article
  • Berge, Jørgen; Johnsen, Geir; Sørensen, Asgeir Johan; Nilssen, Ingunn. (2015) Enabling technology for Arctic research. Pan European Networks: Science and Techology Magazine
    Academic literature review
  • Rodriguez, Francisco; Garrido, J.L.; Sabrino, C; Johnsen, Geir; Riobo, P; Franco, J. (2015) Divinyl chlorophyll a in the marine eukaryotic protist Alexandrium ostenfeldii (Dinophyceae). Environmental Microbiology
    Academic article
  • Berge, Jørgen; Johnsen, Geir; Aarekol, Lena. (2015) Life and light in the dead of night. Museumsutstilling
    Museum exhibition
  • Nilssen, Ingunn; Ødegård, Øyvind; Sørensen, Asgeir Johan; Johnsen, Geir; Moline, Mark A.; Berge, Jørgen. (2015) Integrated environmental mapping and monitoring, a methodological approach to optimise knowledge gathering and sampling strategy. Marine Pollution Bulletin
    Academic article
  • Aarekol, Lena; Johnsen, Geir; Berge, Jørgen. (2015) Polarnatt. Liv og lys i mulm og mørke Polarnighth. Life and death in dead of night. Utstilling
    Museum exhibition
  • Ludvigsen, Martin; Thorsnes, Terje; Hansen, Roy Edgar; Sørensen, Asgeir Johan; Johnsen, Geir; Lågstad, Petter Arthur. (2015) Underwater vehicles for environmental management in coastal areas. IEEE conference proceedings
    Academic chapter/article/Conference paper
  • Tandberg, Anne Helene S.; Berge, Jørgen; Johnsen, Geir; Aarekol, Lena. (2015) POLARNATT - liv og lyst i mulm og mørke. Polarnatt - liv og lyst i mulm og mørke
    Museum exhibition
  • Berge, Jørgen; Johnsen, Geir. (2015) Polarnatt - Liv og lys i mulm og mørke Polar night - life and light in the dead of night. Utstilling på Polarmuseet i Tromsø
    Museum exhibition
  • Cohen, Jonathan H.; Berge, Jørgen; Moline, Mark A.; Sørensen, Asgeir Johan; Last, Kim; Falk-Petersen, Stig. (2015) Is ambient light during the high Arctic polar night sufficient to act as a visual cue for zooplankton?. PLOS ONE
    Academic article
  • Berge, Jørgen; Renaud, Paul; Darnis, Gérald; Cottier, Finlo; Last, Kim; Gabrielsen, Tove M.. (2015) In the dark: a review of ecosystem processes during the Arctic polar night. Progress in Oceanography
    Academic article
  • Berge, Jørgen; Daase, Malin; Renaud, Paul; Ambrose, William G. Jr.; Darnis, Gérald; Last, Kim S. (2015) Unexpected levels of biological activity during the polar night offer new perspectives on a warming Arctic. Current Biology
    Academic article

2014

  • Pettersen, Ragnhild; Johnsen, Geir; Bruheim, Per; Andreassen, Trygve. (2014) Development of hyperspectral imaging as a bio-optical taxonomic tool for pigmented marine organisms. Organisms Diversity & Evolution
    Academic article
  • Valle, Kristin Collier; Nymark, Marianne; Aamot, Inga; Hancke, Kasper; Winge, Per; Andresen, Kjersti. (2014) System responses to equal doses of photosynthetically usable radiation of blue, green, and red light in the marine diatom Phaeodactylum tricornutum. PLOS ONE
    Academic article
  • Lund, Lene; Johnsen, Geir; Bakken, Torkild; Gabrielsen, Tove. (2014) Morphological diversity in Laminaria digitata - different species or different phenotypes?. Norwegian University of Science and Technology, Department of Biology
    Masters thesis
  • Valle, Kristin Collier; Johnsen, Geir; Bones, Atle M. (2014) Photoacclimation mechanisms and light responses in marine micro- and macroalgae. NTNU
    Doctoral dissertation
  • Hallerud, Charlotte; Johnsen, Geir; Aamot, Inga. (2014) Pigment composition of macroalgae from a Norwegian kelp forest. NTNU
    Masters thesis
  • Kjerstad, Ingrid; Johnsen, Geir; Sørensen, Asgeir Johan; Bakken, Torkild. (2014) Underwater Imaging and the effect of Inherent Optical Properties on image quality. NTNU
    Masters thesis
  • Førde, Henny; Reitan, Kjell Inge; Johnsen, Geir. (2014) Development of bryozoan fouling on cultivated kelp (Saccharina latissima) in Norway. NTNU
    Masters thesis
  • Hatlebakk, Maja; Johnsen, Geir; Søreide, Janne. (2014) Effect of lipids and fatty acid composition on success of reproduction in Calanus glacialis. NTNU
    Masters thesis
  • Ødegård, Øyvind; Ludvigsen, Martin; Johnsen, Geir; Sørensen, Asgeir Johan; Ekehaug, Stefan; Dukan, Fredrik. (2014) Managing data from multiple sensors in an interdisciplinary research cruise. Amsterdam University Press
    Academic chapter/article/Conference paper
  • Kleiven, Wanda; Johnsen, Geir; Ardelan, Murat Van. (2014) Elemental composition in various marine brown, green and red macro algae with respect to season and tissue age. NTNU
    Masters thesis
  • Kvernvik, Ane Cecilie; Johnsen, Geir; Aamot, Inga. (2014) How lamina age influence photosynthetic response to light variations in Saccharina latissima. NTNU
    Masters thesis
  • Ludvigsen, Martin; Johnsen, Geir; Sørensen, Asgeir Johan; Lågstad, Petter Arthur; Ødegård, Øyvind. (2014) Scientific Operations Combining ROV and AUV in the Trondheim Fjord. Marine Technology Society journal
    Academic article
  • Johnsen, Geir; Candeloro, Mauro; Berge, Jørgen; Moline, Mark A.. (2014) Glowing in the dark: Discriminating patterns of bioluminescence from different taxa during the Arctic polar night. Polar Biology
    Academic article
  • Hansen, Ingrid; Pettersen, Ragnhild; Beuchel, Frank; Cochrane, Sabine; Frantzen, marianne; Ekehaug, Stefan. (2014) Underwater hyperspectral imaging (UHI) for environmental mapping and monitoring of seabed habitats. Ocean Optics
    Abstract
  • Cohen, Jonathan; Cronin, Heather; Moline, Mark A.; Berge, Jørgen; Johnsen, Geir; Sørensen, Asgeir Johan. (2014) Are krill eyes useful in the high Arctic polar night?. Ocean Optics
    Abstract
  • Johnsen, Geir; Ekehaug, Stefan; Hansen, Ingrid; Sørensen, Asgeir Johan. (2014) The use of underwater hyperspectral imaging deployed on remotely operated vehicles to identify, map and monitor bio-geo-chemical objects of interest. Ocean Optics
    Abstract
  • Aamot, Inga; Pokrzywinski, Kaytee; Johnsen, Geir; Berge, Jørgen; Sørensen, Asgeir Johan. (2014) Light Climate and Status of the Photosynthetic Machinery in Macroalgae in the Polar Night. Ocean Optics
    Abstract
  • Nornes, Stein Melvær; Candeloro, Mauro; Ødegård, Øyvind; Johnsen, Geir; Sørensen, Asgeir Johan. (2014) Photomosaic camera as simultaneous data collector and navigation aid on unmanned underwater vehicles. Ocean Optics
    Abstract
  • Nilssen, Ingunn; Ødegård, Øyvind; Johnsen, Geir; Sørensen, Asgeir Johan; Berge, Jørgen; Nornes, Stein Melvær. (2014) Integrated environmental monitoring; a methodological approach to optimise knowledge gathering and sampling strategy. Ocean Optics
    Abstract
  • Bones, Atle M.; Johnsen, Geir; Brembu, Tore; Valle, Kristin Collier. (2014) Photoacclimation mechanisms and light responses in marine micro- and macroalgae. Doktoravhandlinger ved NTNU (74)
    Doctoral dissertation
  • Johnsen, Geir; Candeloro, Mauro; Berge, Jørgen; Moline, Mark A.. (2014) Erratum to: Glowing in the dark: discriminating patterns of bioluminescence from different taxa during the Arctic polar night. Polar Biology
    Errata
  • Berge, Jørgen; Cottier, Finlo; Varpe, Øystein; Renaud, Paul; Falk-Petersen, Stig; Kwasniewski, Sawomir. (2014) Arctic complexity: A case study on diel vertical migration of zooplankton. Journal of Plankton Research
    Academic article
  • Eldevik, Tor; Reigstad, Marit; Falck, Eva; Gerland, Sebastian; Jentoft, Sissel; Johnsen, Geir. (2014) Arven efter Nansen. Forskningsplan for det sentrale og nordlige Barentshavet. UiT Norges arktiske universitet UiT Norges arktiske universitet
    Report
  • Hancke, Kasper; Hovland, Erlend Kjeldsberg; Volent, Zsolt; Pettersen, Ragnhild; Johnsen, Geir; Moline, Mark A.. (2014) Optical properties of CDOM across the Polar Front in the Barents Sea: Origin, distribution and significance. Journal of Marine Systems
    Academic article
  • Hovland, Erlend Kjeldsberg; Hancke, Kasper; Alver, Morten; Drinkwater, Kennneth F.; Høkedal, Jo; Johnsen, Geir. (2014) Optical impact of an Emiliania huxleyi bloom in the frontal region of the Barents Sea. Journal of Marine Systems
    Academic article

2013

  • Ingrid, Hansen; Johnsen, Geir; Sørensen, Asgeir Johan. (2013) Optical Mapping of Cold-water Corals in Trondheimsfjorden and Svalbard. NTNU
    Masters thesis
  • Johnsen, Geir; Sørensen, Asgeir Johan; Ekehaug, Stefan. (2013) The use of side scan and synthetic aperture sonar mounted on autonomous underwater vehicles for biological habitat mapping. MSc Thesis (2013)
    Masters thesis
  • Båtnes, Anna Solvang; Miljeteig, Cecilie; Berge, Jørgen; Greenacre, Michael; Johnsen, Geir. (2013) Quantifying the light sensitivity of Calanus spp. during the polar night: potential for orchestrated migrations conducted by ambient light from the sun, moon, or aurora borealis. Polar Biology
    Academic article
  • Pettersen, Ragnhild; Johnsen, Geir. (2013) Identification of marine organisms using Chemotaxonomy and Hyperspectral imaging. Doktoravhandlinger ved NTNU (292)
    Doctoral dissertation
  • Båtnes, Anna Solvang; Johnsen, Geir. (2013) Light in the dark – the role of irradiance in the high Arctic marine ecosystem during polar night. Doktoravhandlinger ved NTNU (151)
    Doctoral dissertation
  • Johnsen, Geir; Volent, Zsolt; Dierssen, Heidi; Pettersen, Ragnhild; Ardelan, Murat Van; Søreide, Fredrik. (2013) Underwater hyperspectral imagery to create biogeochemical maps of seafloor properties. Woodhead Publishing Limited
    Academic chapter/article/Conference paper
  • Ludvigsen, Martin; Johnsen, Geir; Lågstad, Petter Arthur; Sørensen, Asgeir Johan; Ødegård, Øyvind. (2013) Scientific operations combining ROV and AUV in the Trondheim Fjord. IEEE conference proceedings
    Academic chapter/article/Conference paper
  • Bones, Atle M.; Johnsen, Geir; Brembu, Tore; Nymark, Marianne. (2013) Light responses in the marine diatom Phaeodactylum tricornutum. Doktoravhandlinger ved NTNU (378)
    Doctoral dissertation
  • Berge, Jørgen; Johnsen, Geir; Falk-Pettersen, Stig. (2013) Mørkets hemmeligheter. Svalbardposten
    Popular scientific article
  • Nymark, Marianne; Valle, Kristin Collier; Hancke, Kasper; Winge, Per; Andresen, Kjersti; Johnsen, Geir. (2013) Molecular and photosynthetic responses to prolonged darkness and subsequent acclimation to re-illumination in the diatom Phaeodactylum tricornutum. PLOS ONE
    Academic article
  • Hovland, Erlend Kjeldsberg; Dierssen, Heidi; Ferreira, Ana Sofia; Johnsen, Geir. (2013) Dynamics regulating major trends in Barents Sea temperatures and subsequent effect on remotely sensed particulate inorganic carbon. Marine Ecology Progress Series
    Academic article

2012

  • Bjørdalsbakke, Lise Kristin; Johnsen, Geir; Bakken, Torkild; Berge, Jørgen. (2012) Population structure, parasitism and prey preference in Sclerocrangon boreas and S. ferox, Svalbard. NTNU
    Thesis at a second degree level
  • Hovland, Erlend Kjeldsberg; Johnsen, Geir; Sakshaug, Egil; Folkestad, Are. (2012) Bio-optics and ecology in Emiliania huxleyi blooms: Field and remote sensing studies in Norwegian water. NTNU
    Doctoral dissertation
  • Berge, Jørgen; Båtnes, Anna Solvang; Johnsen, Geir; Blackwell, Susan; Moline, Mark A.. (2012) Bioluminescence in the high Arctic during the polar night. Marine Biology
    Academic article
  • Belseth, Elen; Johnsen, Geir; Berge, Jørgen. (2012) Eco-physiology of the Arctic kelp Laminaria solidungula. NTNU Master thesis
    Masters thesis
  • Fremstedal, Ane Sofia Viset; Bruheim, Per; Sletta, Håvard; Johnsen, Geir. (2012) Utvikling og optimalisering av protokoll for massespektrometrisk metabolsk profilering av adherente humane celler. NTNU Master theses
    Masters thesis
  • Gabrielsen, Tove M; Quillfeldt, Cecilie von; Johnsen, Geir; Berge, Jørgen. (2012) Varm vinter, sen vår i fjorden. Svalbardposten
    Reader opinion piece
  • Elde, Anette; Pettersen, Ragnhild; Bruheim, Per; Järnegren, Johanna; Johnsen, Geir. (2012) Pigmentation and Spectral Absorbance Signatures in Deep-Water Corals from the Trondheimsfjord, Norway. Marine Drugs
    Academic article
  • Roy, Suzanne; Llewellyn, Carole; Egeland, Einar Skarstad; Johnsen, Geir. (2012) Phytoplankton Pigments: Characterization, Chemotaxonomy and Applications in Oceanography. Cambridge University Press Cambridge Environmental Chemistry Series (2012)
    Academic anthology/Conference proceedings

2011

  • Thoen, Hanne Halkinrud; Johnsen, Geir; Berge, Jørgen. (2011) Pigmentation and spectral absorbance in the deep-sea arctic amphipods Eurythenes gryllus and Anonyx sp. Polar Biology
    Academic article
  • Andersen, Hanne Kile; Johnsen, Geir; Bakken, Torkild. (2011) Gastropods Associated with Laminaria hyperborea and Saccorhiza polyschides in a Norwegian Kelp Forest: Comparison of Sampling and In Situ Imaging Techniques. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Brunet, Christophe; Johnsen, Geir; Lavaud, Johan; Roy, Suzanne. (2011) Pigments and photoacclimation processes. Cambridge University Press
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Bricaud, Annick; Nelson, Norman; Prézelin, Barbara; Bidigare, Robert. (2011) In vivo bio-optical properties of phytoplankton pigments. Cambridge University Press
    Academic chapter/article/Conference paper
  • Volent, Zsolt; Johnsen, Geir; Hovland, Erlend Kjeldsberg; Folkestad, Are; Olsen, Lasse Mork; Tangen, Karl. (2011) Improved monitoring of phytoplankton bloom dynamics in a Norwegian fjord by integrating satellite data, pigment analysis, and Ferrybox data with a coastal observation network. Journal of Applied Remote Sensing
    Academic article
  • Johnsen, Geir; Moline, Mark; Pettersson, Lasse H.; Pinckney, J. L.; Pozdnyakov, Dmitry; Egeland, Einar Skarstad. (2011) Optical monitoring of phytoplankton bloom pigment signatures. Cambridge University Press
    Academic chapter/article/Conference paper
  • Llewellyn, Carole A.; Roy, Suzanne; Johnsen, Geir; Egeland, Einar Skarstad; Chauton, Matilde ; Hallegraeff, Gustaff. (2011) Perspectives on future directions. Cambridge University Press
    Academic chapter/article/Conference paper
  • Roy, Suzanne; Llewellyn, Carole; Egeland, Einar Skarstad; Johnsen, Geir. (2011) Preface. Cambridge University Press
    Foreword
  • Roy, Suzanne; Llewellyn, Carole; Egeland, Einar Skarstad; Johnsen, Geir. (2011) Acknowledgements. Cambridge University Press
    Other
  • Roy, Suzanne; Llewellyn, Carole; Egeland, Einar Skarstad; Johnsen, Geir. (2011) Phytoplankton pigments : characterization, chemotaxonomy and applications in oceanography. Cambridge University Press Cambridge Environmental Chemistry Series (2011)
    Academic anthology/Conference proceedings
  • Jouenne, Fabien; Eikrem, Wenche; Le Gall, F; Marie, Dominique; Johnsen, Geir; Vaulot, Daniel. (2011) Prasinoderma singularis sp. nov. (Prasinophyceae, Chlorophyta), a Solitary Coccoid Prasinophyte from the South-East Pacific Ocean. Protist
    Academic article
  • Pettersen, Ragnhild; Johnsen, Geir; Berge, Jørgen; Hovland, Erlend Kjeldsberg. (2011) Phytoplankton chemotaxonomy in waters around the Svalbard archipelago reveals high amounts of Chl b and presence of gyroxanthin-diester. Polar Biology
    Academic article

2010

  • Thoen, Hanne Halkinrud; Johnsen, Geir; Berge, Jørgen. (2010) Pigmentation and spectral absorbance in the deep-sea arctic amphipods Eurythenes gryllus and Anonyx sp. Polar Biology
    Academic article
  • Aamot, Inga; Berge, Jørgen; Hancke, Kasper; Johnsen, Geir; Moline, Mark; Schofield, Oscar. (2010) NORUS - Technology Development for Marine Monitoring and Ocean Observation:An North America-Norway educational program. http://ipy-osc.no/abstract/
    Abstract
  • Johnsen, Geir; Søreide, Fredrik. (2010) Underwater hyperspectral imaging of marine mineral deposits. Underwater Mining meeting Institute (UMI)
    Abstract

2009

  • Sakshaug, Egil; Johnsen, Geir; Kovacs, Kit M.. (2009) Ecosystem Barents Sea. Tapir Akademisk Forlag Tapir Akademisk Forlag
    Non-fiction book
  • Johnsen, Geir; Nepstad, Ina. (2009) Cloning and characterisation of interleukin-6 and interleukin-11b in Atlantic halibut (Hippoglossus hippoglossus). NTNU, Institutt for biologi
    Masters thesis
  • Elde, Anette Cecilie; Johnsen, Geir. (2009) Pigmentation in deep-water corals from the Trondheimsfjord, Norway. NTNU, Institutt for biologi
    Masters thesis
  • Thoen, Hanne Halkinrud; Johnsen, Geir. (2009) Pigmentation in the Arctic deep-sea amphipods Eurythenes gryllus and Anonyx sp. NTNU, Institutt for biologi
    Masters thesis
  • Øye, Ane-Marte; Johnsen, Geir. (2009) Photobioreactor time-series of a simulated bloom of Emiliania huxleyi. NTNU, Institutt for biologi
    Masters thesis
  • Sakshaug, Egil; Johnsen, Geir; Kovacs, Kit. (2009) Ecosystem Barents Sea. Tapir Akademisk Forlag Tapir Akademisk Forlag
    Academic anthology/Conference proceedings
  • Johnsen, Geir; Volent, Z; Sakshaug, E.; Sigernes, Fred; Pettersson, L.H.. (2009) Remote sensing in the Barents Sea. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Sakshaug, E.; Johnsen, Geir; Kristiansen, Svein; Quillfeldt, C.v.; Rey, F.; Slagstad, D.. (2009) Phytoplankton and primary production. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Sakshaug, E.; Johnsen, Geir; Volent, Z. (2009) Light. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Quillfeldt, C.v.; Hegseth, E.N.; Johnsen, Geir; Sakshaug, E.; Syvertsen, E.E.. (2009) Ice algae. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • von Quillfeldt, Cecilie H.; Hegseth, Else Nøst; Johnsen, Geir; Sakshaug, Egil; Syvertsen, Erik. (2009) Ice algae. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • von Quillfeldt, Cecilie; Hegseth, Else Nøst; Johnsen, Geir; Sakshaug, Egil; Syvertsen, Erik E.. (2009) Ice algae. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Sakshaug, Egil; Johnsen, Geir; Kristiansen, Svein; von Quillfeldt, Cecilie; Rey, Francisco; Slagstad, Dag. (2009) Phytoplankton and primary production. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Sakshaug, Egil; Johnsen, Geir; Volent, Z.. (2009) Light. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Volent, Zsolt; Sakshaug, Egil; Sigernes, Fred; Pettersson, Lasse H.. (2009) Remote sensing in the Barents Sea. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Sakshaug, E.; Johnsen, Geir; Kovacs, Kit. (2009) Ecosystem Barents Sea. Tapir Akademisk Forlag Tapir Akademisk Forlag
    Textbook
  • Berge, Jørgen; Cottier, Finlo; Last, Kim S.; Varpe, Øystein; Leu, Eva; Søreide, Janne. (2009) Diel vertical migration of Arctic zooplankton during the polar night. Biology Letters
    Academic article
  • Nymark, Marianne; Valle, Kristin Collier; Brembu, Tore; Winge, Per; Hancke, Kasper; Andresen, Kjersti. (2009) An integrated analysis of molecular acclimation to high light in the marine diatom Phaeodactylum tricornutum. PLOS ONE
    Academic article
  • Berge, Jørgen; Lønne, Ole Jørgen; Renaud, Paul; Johnsen, Geir; Gulliksen, Bjørn; Varpe, Øystein. (2009) Polartorsken - vil den bli utkonkurrert av sørlige fiskearter?. Svalbardposten
    Popular scientific article
  • Evertsen, Jussi; Johnsen, Geir. (2009) In vivo and in vitro differences in chloroplast functionality in the two north Atlantic sacoglossans (Gastropoda, Opisthobranchia) Placida dendritica and Elysia viridis. Marine Biology
    Academic article
  • Volent, Z; Johnsen, Geir; Sigernes, Fred. (2009) Microscopic hyperspectral imaging used as a bio-optical taxonomic tool for micro- and macroalgae. Applied Optics
    Academic article

2008

  • Båtnes, Anna Solvang; Johnsen, Geir. (2008) Trophic interaction between little auks and their zooplankton prey in a high Arctic fjord based on lipid analyses. NTNU, Institutt for biologi
    Masters thesis
  • Hancke, Torunn Beate; Hancke, Kasper; Johnsen, Geir; Sakshaug, Egil. (2008) Rate of O2 production derived from pulse-amplitude-modulated fluorescence: Testing three biooptical approaches against measured O2-production rate. Journal of Phycology
    Academic article
  • Bredholt, Harald; Fjærvik, Espen; Johnsen, Geir; Zotchev, Sergey. (2008) Actinomycetes from sediments in the Trondheim Fjord, Norway: Diversity and biological activity. Marine Drugs
    Academic article
  • Bakken, Torkild; Evertsen, Jussi; Johnsen, Geir. (2008) Vitenskapelig dykking - behov for endringer i forskriften. Dykkenytt : informasjonsorgan for dykkeindustrien
    Article in business/trade/industry journal
  • Hancke, Kasper; Hancke, Torunn Beate; Olsen, Lasse Mork; Johnsen, Geir; Glud, RN. (2008) Temperature effects on microalgal photosynthesis-light responses measured by O2 production, pulse-amplitude-modulated fluorescence, and C-14 assimilation. Journal of Phycology
    Academic article
  • Hovland, Erlend Kjeldsberg; Johnsen, Geir; Moline, Mark. (2008) Combined use of AUV and hyperspectral imaging to mapping sea-surface and macroalgae. Ocean Optics
    Abstract

2007

  • Kleiven, Mona; Johnsen, Geir. (2007) Pigmentation in Halocynthia pyriformis from Isfjorden, Spitsbergen. NTNU, Institutt for biologi
    Masters thesis
  • Hovland, Erlend Kjeldsberg; Sakshaug, Egil; Johnsen, Geir. (2007) Tracing Coccolithophorid Blooms in the Barents Sea Using MODIS Level-3 Imagery. NTNU, Institutt for biologi
    Masters thesis
  • Stübner, Eike; Johnsen, Geir. (2007) Biogeographical distribution of temperate vs. Arctic benthic species around Svalbard. NTNU, Institutt for biologi
    Masters thesis
  • Pettersen, Ragnhild; Johnsen, Geir. (2007) Phytoplankton systematics and pigmentation in the Arctic. NTNU, Institutt for biologi
    Masters thesis
  • Hancke, Kasper; Johnsen, Geir. (2007) Photosynthetic responses as a function of light and temperature: Field and laboratory studies on marine microalgae. NTNU, Institutt for biologi
    Doctoral dissertation
  • Johnsen, Geir; Volent, Zsolt; Sigernes, F.. (2007) Fine scale studies using hyper-spectral remote sensing. ESSAS Meeting in Marine Arctic Climate
    Report
  • Elvestrand, Jostein; Johnsen, Geir; Sneli, Jon-Arne. (2007) Morphometry and patterns of growth in Acesta excavata (Bivalvia: Limidae) from the Trondheimsfjord, Norway. NTNU, Institutt for biologi
    Thesis at a second degree level
  • Cibic, Tamara; Blasutto, Oriana; Hancke, Kasper; Johnsen, Geir. (2007) Microphytobenthic species composition, pigment concentration, and primary production in sublittoral sediments of the Trondheimsfjord (Norway). Journal of Phycology
    Academic article
  • Evertsen, Jussi; Burghardt, Ingo; Johnsen, Geir; Wägele, Heike. (2007) Retention of functional chloroplasts in some sacoglossans from the Indo-Pacific and Mediterranean. Marine Biology
    Academic article
  • Ludvigsen, Martin; Sortland, Bjørn; Johnsen, Geir; Singh, Hanumant. (2007) Applications of Geo-Referenced Underwater Photo Mosaics in Marine Biology and Archaeology. Oceanography
    Academic article
  • Johnsen, Geir; Sakshaug, Egil. (2007) Biooptical characteristics of PSII and PSI in 33 species (13 pigment groups) of marine phytoplankton, and the relevance for pulse-amplitude-modulated and fast-repetition-rate fluorometry. Journal of Phycology
    Academic article
  • Edvardsen, B; Eikrem, W; Shalchian-Tabrizi, K; Riisberg, I; Johnsen, Geir; Naustvoll, L. (2007) Verrucophora farcimen gen. et sp nov (Dictyochophyceae, Heterokonta) - A bloom-forming ichthyotoxic flagellate from the Skagerrak, Norway. Journal of Phycology
    Academic article
  • Johnsen, Geir; Volent, Zsolt; Sigernes, F.; Berge, Jørgen; Hovland, Erlend Kjeldsberg; Sakshaug, Egil. (2007) Local hyperspectral imaging of ocean colour from tethered balloons in the Arctic. In Proceedings from Arctic Frontiers: Balancing human use and ecosystem protection. UiT Norges arktiske universitet UiT Norges arktiske universitet
    Report
  • Berge, Jørgen; Schander, C; Pampanin, D.M.; Johnsen, Geir. (2007) The past, present and future of the Mytilus edulis population on Svalbard. In Proceedings from Arctic Frontiers: Balancing human use and ecosystem protection. UiT Norges arktiske universitet UiT Norges arktiske universitet
    Report
  • Hancke, Kasper; Johnsen, Geir; Sakshaug, Egil. (2007) Bio-optical properties and spectral attenuation of photosynthetically available radiation: relation to primary productivity and phytoplankton composition. In Proceedings from Arctic Frontiers: balancing human use and ecosystem protection. UiT Norges arktiske universitet UiT Norges arktiske universitet
    Report
  • Johnsen, Geir. (2007) Arctic Life: Bridging ecosystem function using remote sensing technologies. Svalbard Science Forum
    Popular scientific article
  • Carlsen, BP; Johnsen, Geir; Berge, Jørgen; Kuklinski, P. (2007) Biodiversity patterns of macro-epifauna on different lamina parts of Laminaria digitata and Saccharina latissima collected during spring and summer 2004 in Kongsfjorden, Svalbard. Polar Biology
    Academic article
  • Volent, Z; Johnsen, Geir; Sigernes, Fred. (2007) Kelp forest mapping by use of airborne hyperspectral imager. Journal of Applied Remote Sensing
    Academic article

2006

  • Sylling, Guro; Thingstad, Per Gustav; Johnsen, Geir. (2006) Marin bunndyrfauna (Gastropoda, Bivalvia) - Konsekvenser av åpning av veifylling over Ramsarområdet Tautrasvaet. NTNU, Institutt for biologi
    Masters thesis
  • Carlsen, Beth Paludan; Johnsen, Geir. (2006) Makroepifauna associeret med Laminaria digitata og L. saccharina, Svalbard. NTNU, Institutt for biologi
    Masters thesis
  • Berge, Jørgen; Johnsen, Geir; Nilsen, Frank; Nilsen, Frank; Gulliksen, Bjørn; Slagstad, Dag. (2006) The Mytilus edulis population in Svalbard: how and why. Marine Ecology Progress Series
    Editorial
  • Berge, Jørgen; Johnsen, Geir; Nilsen, Frank; Gulliksen, Bjørn; Slagstad, Dag; Pampanin, Daniella. (2006) The Mytilus edulis population in Svalbard: how and why. Marine Ecology Progress Series
    Academic article
  • Olsen, Lasse Mork; Öztürk, M.; Sakshaug, Egil; Johnsen, Geir. (2006) Photosynthesis-induced phosphate precipitation in seawater: ecological implications for phytoplankton. Marine Ecology Progress Series
    Academic article
  • Rodriguez, F; Chauton, Matilde Skogen; Johnsen, Geir; Andresen, Kjersti; Olsen, Lasse Mork; Zapata, M.. (2006) Photoacclimation in phytoplankton: implications for biomass estimates, pigment functionality and chemotaxonomy. Marine Biology
    Academic article
  • Roy, Suzanne; Egeland, Einar Skarstad; Johnsen, Geir; Llewellyn, Carole; Wright, Simon. (2006) Report of a Workshop on a Follow-Up Volume of the Book "Phytoplankton Pigments in Oceanography". Scientific Committee on Oceanic Research
    Report
  • Johnsen, Geir. (2006) Warming Arctic sees return of blue mussels after 1000 years. National Geographic
    Popular scientific article
  • Onstad, L; Evertsen, Jussi; Johnsen, Geir. (2006) Snegle på solceller. Gemini
    Popular scientific article

2005

  • Hilstad, Kari; Johnsen, Geir. (2005) In situ tidsseriemålinger av lyshøstingsegenskaper og cellekjemi hos marine makroalger i Trondheimsfjorden. NTNU, Institutt for biologi
    Thesis at a second degree level
  • Olsen, Lasse Mork; Johnsen, Geir. (2005) Interactions between marine osmo- and phagotrophs in different physicochemical environments. NTNU, Institutt for biologi
    Doctoral dissertation
  • Valle, Kristin Collier; Johnsen, Geir. (2005) Detection of monthly variation in marine red, brown and green macroalgae by means of in situ video, epifluorescence microscopy and numerical digital image analysis. NTNU, Institutt for biologi
    Thesis at a second degree level
  • Chauton, Matilde Skogen; Johnsen, Geir; Sakshaug, Egil. (2005) Nuclear Magnetic Resonance spectroscopy of marine microalgae: Metabolic profiling and species discrimination from High-resolution Magic Angle Spinning NMR analysis of whole-cell samples. NTNU, Institutt for biologi
    Doctoral dissertation
  • Sakshaug, Egil; Johnsen, Geir. (2005) Absorption, fluorescence excitation and photoacclimation in phytoplankton. Multi-Science Publishing
    Academic chapter/article/Conference paper
  • Berge, Jørgen; Johnsen, Geir; Nilsen, Frank; Gulliksen, Bjørn; Slagstad, Dag. (2005) Ocean temperature oscillations enable reappearance of blue mussels Mytilus edulis in Svalbard after 1000 year absence. Marine Ecology Progress Series
    Academic article
  • Sakshaug, Egil; Johnsen, Geir. (2005) Algal cultures, Analogues of Blooms and Applications. Multi-Science Publishing Multi-Science Publishing
    Academic anthology/Conference proceedings
  • Berge, J; Johnsen, Geir; Nilsen, F; Gulliksen, B; Slagstad, D. (2005) Ocean temperature oscillations causes the reappearance of blue mussels in Svalbard after 1000 years of absence. Marine Ecology Progress Series
    Academic article
  • Bordvik, Hans Otto; Johnsen, Geir. (2005) “En glupsk nellik”. NEWTON websider (NRK)
    Popular scientific article
  • Indergaard, M; Nordtvedt, M; Johnsen, Geir. (2005) Satellittmålinger for miljøet (SISCAL project, NTNU, IBI). Gemini
    Popular scientific article
  • Bordvik, Hans Otto; Johnsen, Geir. (2005) “Forskning og foto under vann”. NEWTON websider (NRK)
    Popular scientific article
  • Burghardt, Ingo; Evertsen, Jussi; Johnsen, Geir; Wägele, Heike. (2005) Solar powered seaslugs - Mutualistic symbiosis of aeolid nudibranchia (Mollusca, Gastropoda, Opisthobranchia) with Symbiodinium. Symbiosis
    Academic article
  • Fossmark, Reidar; Johnsen, Geir; Waldum, Helge; Johannesen, Eli Marie. (2005) Rebound acid hypersecretion after long-term inhibition of gastric acid secretion. Alimentary Pharmacology and Therapeutics
    Academic article

2004

  • Hancke, Torunn Beate; Johnsen, Geir. (2004) SISCAL processor evaluation document. www.siscal.net
    Report
  • Chauton, Matilde Skogen; Tilstone, Gavin; Legrand, Catherine; Johnsen, Geir. (2004) Changes in pigmentation, bio-optical characteristics and photophysiology, during phytoflagellate succession in mesocosms. Journal of Plankton Research
    Academic article

2003

  • Johansen, Torunn Beate; Johnsen, Geir. (2003) SISCAL prototype evaluation document. www.siscal.net. Satellite-based Information System on Coastal Areas and Lakes. IST 2000
    Academic article
  • Johansen, Torunn Beate; Johnsen, Geir. (2003) SISCAL End User Requirement evaluation document. www.siscal.net. Satellite-based Information System on Coastal Areas and Lakes. IST 2000
    Academic article
  • Chauton, Matilde Skogen; Optun, Odd Inge; Bathen, F. T; Volent, Z.; Gribbestad, Ingrid S.; Johnsen, Geir. (2003) HR MAS 1H NMR spectroscopy analysis of whole cells of marine microalgae. Marine Ecology Progress Series
    Academic article
  • Figueroa, F. L.; Escassi, L.; Perez-Rodriguez, E.; Korbee, N.; Johnsen, Geir. (2003) Effects of the irradiance in the short-term on accumulation of mycosporine like amino acids in sun and shade species of the red algal genus Porphyra. Photochemistry and Photobiology
    Academic article

2002

  • Johansen, Torunn Beate; Johnsen, Geir. (2002) End User Requirements document. [Mangler utgivernavn]
    Report
  • Johansen, Torunn Beate; Johnsen, Geir. (2002) End User requirement evaluation document. [Mangler utgivernavn]
    Report
  • Gileptis, Laura; Johnsen, Geir; Moxness, Helge; Norwich, Inger; Vangen, Steffen. (2002) Modul for mønstergjenkjenning/klassifisering i DynamicImager ved bruk av backpropagation-algoritmen. Piksel'n : Organ for NOBIM (Norsk forening for bildebehandling og mønstergjenkjenning)
    Academic article
  • Millie, David; Schofield, Oscar; Kirkpatrick, Gary J.; Johnsen, Geir; Evens, Tim J.. (2002) Using absorbance and fluorescence spectra to discriminate microalgae. European journal of phycology
    Academic article
  • Johnsen, Geir; Børsheim, Knut Yngve; Johansen, Torunn Beate. (2002) Production and mortality of phytoplankton and sea-ice microalgae in the southern ocean. Rapportserie (Norsk polarinstitutt)
    Academic article

2001

  • Johnsen, Geir. (2001) SISCAL End User Requirement Satellite-based Information System on Coastal Areas and Lakes. Information Society Technologies Programme funded by the European Comm
    Report
  • Wägele, Heike; Johnsen, Geir. (2001) New results on histology and photosynthetic performance of solar-powered� opisthobranchs (Mollusca, Gastropoda, Opisthobranchia) containing symbiotic chloroplasts or zooxanthellae. Organisms Diversity & Evolution
    Academic article
  • Legrand, Catherine; Johnsen, Geir; Graneli, Edna; Sakshaug, Egil. (2001) (Proceedings of the 9th International conference on Harmful Algal Blooms. Hobart, Tasmania, 7-11 February 2000.) Effect of polyamines on growth and toxicity of Chrysochromulina leadbeateri, Haptophytae. Phycologia
    Academic article
  • Graneli, Edna; Legrand, Catherine; Carlsson, Per; Johnsen, Geir; Maestrini, Serge Y.; Reichelt, Michael. (2001) (Proceedings of the 9th International conference on Harmful Algal Blooms. Hobart, Tasmania, 7-11 February 20). Structuration of marine phytoplankton communities subjected to different levels of N, P and Si limitation in a mesocosm experiment (summary paper). Phycologia
    Academic article
  • Legrand, Catherine; Johansson, Niclas; Johnsen, Geir; Børsheim, Knut Yngve; Graneli, Edna. (2001) Phagotrophy and toxicity in the photosynthetic Prymnesium patelliferum (Haptophyte). Limnology and Oceanography
    Academic article

1998

  • Johnsen, Geir; Samset, O.; Sakshaug, Egil. (1998) Bio-optical classification of potential harmful chlorophyll c -containing prymnesiophyte blooms in Scandinavian water.
    Academic chapter/article/Conference paper
  • Seppala, J; Johnsen, Geir; Babichenko, S; Leeben, A; Poryvkina, L; Shalapyonok, [Mangler fornavn]. (1998) In vivo light absorption by photosynthetic and photoprotective algal pigments: Methodology and the effects of light acclimation and nutrient limitation. Report Series in Geophysics
    Academic article
  • Johnsen, Geir; Dalløkken, Runar; Aure, J; Skjoldal, H. R. (1998) Photophysiology and environmental conditions during a toxic bloom of Chrysochromulina leadbeateri (Prymnesiophyceae). International symposium on Harmful Algal Blooms
    Academic article
  • Johnsen, Geir; Eikrem, W.; Dalløkken, R.; Aure, J.; Skjoldal, H. R.. (1998) Physiology and environmental conditions during a toxic blooms of Chrysochromulina leadbeateri Prymnesiophyceae. Journal of Phycology
    Academic article

1997

  • Johnsen, Geir; Volent, Z.; Tangen, K.; Sakshaug, Egil. (1997) Time series of harmful and benign phytoplankton blooms in northwest European waters using the Seawatch buoy system.
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Volent, Z.; Tangen, K.; Sakshaug, Egil. (1997) Time series of harmful and benign phytoplankton blooms in northwest European waters using the Seawatch buoy system.
    Academic chapter/article/Conference paper
  • Grzymski, J.; Johnsen, Geir; Sakshaug, Egil. (1997) The significance of intracellular self-shadingon the bio-optical properties of brown, red and green macroalgal species. Journal of Phycology
    Academic article
  • Johnsen, Geir; Prezelin, B. B.; Jovine, R. V. M.. (1997) Fluorescence excitation spectra and light utiliation in two red tide dinoflagellates. Limnology and Oceanography
    Academic article
  • Millie, D.; Schofield, O. M.; Kirkpatrick, G. J.; Johnsen, Geir; Tester, P. A.; Vinyard, B. T.. (1997) Phytoplankton pigments and absorption spectra as potential bio-markers for harmful algal blooms: A case study of the Florida red-tide dinoflagellat Gymnodinium breve. Limnology and Oceanography
    Academic article
  • Grzymski, J.; Johnsen, Geir; Sakshaug, Egil. (1997) The significance of intracellular self-shading on the bio-optical properties of brown, red and green macroalgal species. Journal of Phycology
    Academic article

1996

  • Vernet, M.; Mitchell, B.G.; Sakshaug, Egil; Johnsen, Geir; Iturriaga, R.; Wassmann, P.. (1996) Evidence for a novel pigment with in vivo absorption maximum at 708 nm associated with Phaeocystis cf. pouchetii blooms. Marine Ecology Progress Series
    Academic article
  • Schofield, O.; Prezelin, B. B.; Johnsen, Geir. (1996) Wavelength-dependency of maximum quantum yield of carbon fixation for two red tide dinoflagellates, Heterocapsa pygmaea and prorocentrum minimum. Journal of Phycology
    Academic article
  • Johnsen, Geir; Sakshaug, Egil. (1996) Light harvesting in bloom-forming marine phytoplankton: Species-specifity and photoacclimation,. Scientia Marina
    Academic article
  • Johnsen, Geir; Volent, Z; Tangen, K; Sakshaug, Egil. (1996) Time-series of potential toxic phytoplankton blooms in North European waters in 1993 using the SEAWATCH-Europe buoy system. EOS
    Academic article
  • Vernet, M.; Mitchell, B. G.; Sakshaug, Egil; Johnsen, Geir; Iturriaga, R.; Wassmann, P.. (1996) Evidence for a novel pigment with in vivo absorption maximum at 708 nm associated with Phaeocystis sp. blooms. Marine Ecology Progress Series
    Academic article
  • Millie, D; Shofield, O. M; Kirkpatrick, G. J; Tester, P. A; Johnsen, Geir. (1996) Using bio-optical characterisics as bio-markers for harmful algal blooms: A case study of the Florida red-tide dinoflagellate,. EOS
    Academic article

1995

  • Johnsen, Geir; Sakshaug, Egil. (1995) Light harvesting in bloom-forming marine phytoplankton: species-specificity and photoadaption. Scientia Marina
    Academic article
  • Egeland, E.; Johnsen, Geir; Eikrem, W.; Liaaen-Jensen, S.; Throndsen, J.. (1995) The pigments of Bathycoccus prasinos. Journal of Phycology
    Academic article
  • Jovine, R. V.; Johnsen, Geir; Prezelin, B. B.. (1995) Isolation of membrane bound chlorophyll a-chlorofhyll c binding light harvesting complexes from the dinoflagellates heterocapsa pygmaea and Prorocentrum minimum. Photosynthesis Research
    Academic article

1994

  • Johnsen, Geir. (1994) Light Harvesting and Utiliation in Marine Phytoplankton: Species-Specific and Photoadaptive Responses. Dr. Scient. Thesis in Marine Botany, University of Trondheim
    Doctoral dissertation
  • Johnsen, Geir; Nelson, N. B.; Jovine, R. V. M.; Prezelin, B. B.. (1994) Chromoprotein- and pigment-dependent modeling of spectral light absorption in two dinoflagellates, Prorocentrum minimum and Heterocapsa pygmaea. Marine Ecology Progress Series
    Academic article
  • Jovine, R. V; Johnsen, Geir; Prezelin, B. B. (1994) Photoadaptation of Prorocentrum minimum and Heterocapsa pygmaea (Dinoflagellates): Chromoprotein changes and the consequenses for spectral absorption. EOS
    Academic article
  • Jovine, R. V.; Schofield, O.; Johnsen, Geir; Prezelin, B. B.. (1994) Photoacclimatory differences in the light-harvesting complex of the bloom forming dinoflagellates Heterocapsa pygmaea and Prorocentrum minimum. Journal of Phycology
    Academic article
  • Johnsen, Geir; Samset, O.; Granskog, L.; Sakshaug, Egil. (1994) In vivo absorption characteristics in 10 classes of phytoplankton: Taxonomic characteristics and responses to photoadaption by means of discriminant and HPLC analysis. Marine Ecology Progress Series
    Academic article

1993

  • Johnsen, Geir; Sakshaug, Egil. (1993) Bio-optical characteristics and photoadaptive responses in the toxic and bloomforming dinoflagellates Gyrodinium aureolum, Gymnodinium galatheanum two strains of Prorocentrum minium. Journal of Phycology
    Academic article
  • Gilstad, Mona; Johnsen, Geir; Sakshaug, Egil. (1993) Photosynthetic parameters, pigment composition and respiration rates of the marine diatom Skeletonema costatum grown in continuous light and a 12:1 light-dark cycle. Journal of Plankton Research
    Academic article
  • Volent, Zsolt; Johnsen, Geir. (1993) Presentation of an optical sensor-"OPTISENS" designed for Eulerian measurements of Phytoplankton on a buoy. Underwater light measurements. Proceedings from International Symposium on high latitude optics.
    Academic article

1992

  • Syvertsen, E.; Hegseth, E; Johnsen, Geir; Sakshaug, Egil; Gulliksen, B; Lønne, O. J. (1992) Livet i isen (The life in the ice). In Økosystem Barentshavet. [Mangler utgivernavn]
    Non-fiction book
  • Sakshaug, Egil; Kristiansen, S; Syvertsen, E; Eilertsen, H. C; Gilstad, M; Hegseth, E. N. (1992) Planktonalger (Phytoplankton). In Økosystem Barentshavet. [Mangler utgivernavn]
    Non-fiction book
  • Johnsen, Geir; Samset, Oddgeir; Zsolt, Volent. (1992) Bio-optical characteristicts of phytoplankton in relation to remote sensing. ABOOS (Autonomous Bio-Optical Observing Systems) Scientific Symposium : Abstracts
    Academic article
  • Volent, Zsolt; Johnsen, Geir. (1992) Presentation of an optical sensor-"OPTISENS" designed for Eulerian measurements of Phytoplankton on a moored buoy. ABOOS (Autonomous Bio-Optical Observing Systems) Scientific Symposium : Abstracts
    Academic article
  • Johnsen, Geir; Sakshaug, Egil; Vernet, Maria. (1992) Pigment composition, spectral characteriation and photosynthetic parameters in Chrysochromulina polylepis. Marine Ecology Progress Series
    Academic article

1991

  • Johnsen, Geir. (1991) Proceedings from a scientific working meeting. Fisken og Havet
    Academic article
  • Johnsen, Geir; Hegseth, Else Nøst. (1991) Photoadaptation of sea-ice microalgae in the Barents Sea. Polar Biology
    Academic article
  • Johnsen, Geir. (1991) Identification of Chrysochromulina leadbeateri by means of remote sensing. Fisken og Havet
    Academic article
  • Sakshaug, Egil; Johnsen, Geir; Samset, Oddgeir; Zsolt, Volent. (1991) Identification of phytoplankton blooms by means of remote sensing. Environment Northern Seas
    Academic article
  • Sakshaug, Egil; Johnsen, Geir; Andresen, Kjersti; Vernet, Maria. (1991) Modeling of light-dependent algal photosynthesis and growth: Experiments with the Barents Sea diatoms Thalassiosira nordensskioeldii and Chaetocero furcellatus. Deep-Sea Research Part II: Topical Studies in Oceanography
    Academic article

Journal publications

  • Bakken, Sivert; Henriksen, Marie Bøe; Birkeland, Roger; Langer, Dennis David; Oudijk, Adriënne Esmeralda; Berg, Simen. (2023) HYPSO-1 CubeSat: First Images and In-Orbit Characterization. Remote Sensing
    Academic article
  • Williamson, David Roddan; Moreira Fragoso, Glaucia; Majaneva, Sanna Kristiina; Dallolio, Alberto; Halvorsen, Daniel Ørnes; Hasler, Oliver Kevin. (2023) Monitoring Algal Blooms with Complementary Sensors on Multiple Spatial and Temporal Scales. Oceanography
    Academic article
  • Grant, Stephen Denis; Johnsen, Geir; McKee, David; Zolich, Artur Piotr; Cohen, Jonathan H.. (2023) Spectral and RGB analysis of the light climate and its ecological impacts using an all-sky camera system in the Arctic. Applied Optics
    Academic article
  • Summers, Natalie Maria; Moreira Fragoso, Glaucia; Johnsen, Geir. (2023) Photophysiologically active green, red, and brown macroalgae living in the Arctic Polar Night. Scientific Reports
    Academic article
  • Schartmuller, Bernhard; Anderson, Philip; Mckee, David; Connan-McGinty, Stacey; Kopec, Tomasz Piotr; Daase, Malin Hildegard Elisabeth. (2023) Development and calibration of a high dynamic range and autonomous ocean-light instrument to measure sub-surface profiles in ice-covered waters. Applied Optics
    Academic article
  • Gerland, Sebastian; Ingvaldsen, Randi Brunvær; Reigstad, Marit; Sundfjord, Arild; Bogstad, Bjarte; Chierici, Melissa. (2023) Still Arctic? — The changing Barents Sea. Elementa: Science of the Anthropocene
    Academic literature review
  • Summers, Natalie; Johnsen, Geir; Mogstad, Aksel Alstad; Løvås, Håvard; Fragoso, Glaucia Moreira; Berge, Jørgen. (2022) Underwater Hyperspectral Imaging of Arctic Macroalgal Habitats during the Polar Night Using a Novel Mini-ROV-UHI Portable System. Remote Sensing
    Academic article
  • Fragoso, Glaucia Moreira; Davies, Emlyn John; Fossum, Trygve Olav; Ullgren, Jenny; Majaneva, Sanna; Aberle-Malzahn, Nicole. (2022) Contrasting phytoplankton-zooplankton distributions observed through autonomous platforms, in-situ optical sensors and discrete sampling. PLOS ONE
    Academic article
  • Mogstad, Aksel Alstad; Løvås, Håvard; Sture, Øystein; Johnsen, Geir; Ludvigsen, Martin. (2022) Remote Sensing of the Tautra Ridge: An Overview of the World’s Shallowest Cold-Water Coral Reefs. Frontiers in Marine Science
    Academic article
  • Connan-McGinty, Stacey; Banas, Neil S.; Berge, Jørgen; Cottier, Finlo Robert; Grant, Stephen; Johnsen, Geir. (2022) Midnight Sun to Polar Night: A Model of Seasonal Light in the Barents Sea. Journal of Advances in Modeling Earth Systems
    Academic article
  • Oudijk, Esmée; Hasler, Oliver Kevin; Øveraas, Henning; Marty, Sabine; Williamson, David Roddan; Svendsen, Torbjørn Karl. (2022) Campaign For Hyperspectral Data Validation In North Atlantic Coastal Waters. Workshop on Hyperspectral Image and Signal Processing, Evolution in Remote Sensing
    Academic article
  • Dona, Angela; Evertsen, Jussi; Johnsen, Geir. (2022) The role of parapodia and lack of photoacclimation in kleptoplasts of the sacoglossan sea slug Plakobranchus ocellatus. Coral reefs
    Academic article
  • Cohen, Jonathan H.; Last, Kim; Charpentier, Corie L.; Cottier, Finlo; Daase, Malin; Hobbs, Laura. (2021) Photophysiological cycles in Arctic krill are entrained by weak midday twilight during the Polar Night. PLoS Biology
    Academic article
  • Cardwell, CR; Berge, Jørgen; Johnsen, Geir. (2021) Arctic voyage shines light on some cold, hard truths. The Herald, UK
    Popular scientific article
  • Bazilchuk, Nancy Reney; Berge, Jørgen; Johnsen, Geir. (2021) Lysforurensning I Arktis kan ha ødelagt forskningsresultater. Gemini.no
    Popular scientific article
  • Ringvold, Halldis; Taite, Morag; Allcock, A. Louise; Vecchione, Michael; Péan, Michel; Sandulli, Roberto. (2021) In situ recordings of large gelatinous spheres from NE Atlantic, and the first genetic confirmation of egg mass of Illex coindetii (Vérany, 1839) (Cephalopoda, Mollusca). Scientific Reports
    Academic article
  • Bakken, Sivert; Johnsen, Geir; Johansen, Tor Arne. (2021) Analysis and Model Development of Direct Hyperspectral Chlorophyll-A Estimation for Remote Sensing Satellites. Workshop on Hyperspectral Image and Signal Processing, Evolution in Remote Sensing
    Academic article
  • Horni, K; Sørensen, Asgeir Johan; Johnsen, Geir; Ludvigsen, Martin. (2021) Internasjonalt forskningsmiljø dykker i Mjøsa etter at Oppland Arbeiderblad skrev om forurensning. Oppland arbeiderblad
    Popular scientific article
  • Bazilchuk, Nancy Reney; Stahl, Annette; Johnsen, Geir; Saad, Aya; Thu, Maren; Nøland, Annecken. (2021) Sporhunden som lukter mikroalger. . Gemini.no
    Popular scientific article
  • Johnsen, Geir; Zolich, Artur; Grant, Stephen; Bjørgum, Rune; Cohen, Jonathan H.; Mckee, David. (2021) All-sky camera system providing high temporal resolution annual time series of irradiance in the arctic. Applied Optics
    Academic article
  • Geoffroy, Maxime; Langbehn, Tom Jasper; Priou, Pierre; Varpe, Øystein; Johnsen, Geir; Le Bris, Arnault. (2021) Pelagic organisms avoid white, blue, and red artificial light from scientific instruments. Scientific Reports
    Academic article
  • Løvås, Håvard; Mogstad, Aksel Alstad; Sørensen, Asgeir Johan; Johnsen, Geir. (2021) A Methodology for Consistent Georegistration in Underwater Hyperspectral Imaging. IEEE Journal of Oceanic Engineering
    Academic article
  • Faltynkova, Andrea; Johnsen, Geir; Wagner, Martin. (2021) Hyperspectral imaging as an emerging tool to analyze microplastics: A systematic review and recommendations for future development. Microplastics and Nanoplastics
    Academic literature review
  • Ramirez-Llodra, Eva; Hilário, Ana; Paulsen, Emil; Costa, Carolina; Bakken, Torkild; Johnsen, Geir. (2020) Benthic Communities on the Mohn’s Treasure Mound: Implications for Management of Seabed Mining in the Arctic Mid-Ocean Ridge. Frontiers in Marine Science
    Academic article
  • Gibbens, Sarah; Berge, Jørgen; Johnsen, Geir; Mckee, David. (2020) As the Arctic warms, light pollution may pose a new treat to marine life. . National Geographic
    Interview Journal
  • Berge, Jørgen; Geoffroy, Maxime; Daase, Malin; Cottier, Finlo Robert; Priou, Pierre; Cohen, Jonathan H.. (2020) Artificial light during the polar night disrupts Arctic fish and zooplankton behavior down to 200 m depth. Communications Biology
    Academic article
  • Saad, Aya; Stahl, Annette; Våge, Andreas; Davies, Emlyn John; Nordam, Tor; Aberle-Malzahn, Nicole. (2020) Advancing Ocean Observation with an AI-driven Mobile Robotic Explorer. Oceanography
    Academic article
  • Fragoso, Glaucia Moreira; Johnsen, Geir; Chauton, Matilde Skogen; Cottier, Finlo Robert; Ellingsen, Ingrid H.. (2020) Phytoplankton community succession and dynamics using optical approaches. Continental Shelf Research
    Academic article
  • Mogstad, Aksel Alstad; Ødegård, Øyvind; Nornes, Stein Melvær; Ludvigsen, Martin; Johnsen, Geir; Sørensen, Asgeir Johan. (2020) Mapping the Historical Shipwreck Figaro in the High Arctic Using Underwater Sensor-Carrying Robots. Remote Sensing
    Academic article
  • Fragoso, Glaucia Moreira; Davies, Emlyn John; Ellingsen, Ingrid H.; Chauton, Matilde Skogen; Fossum, Trygve Olav; Ludvigsen, Martin. (2019) Physical controls on phytoplankton size structure, photophysiology and suspended particles in a Norwegian biological hotspot. Progress in Oceanography
    Academic article
  • Kleiven, Wanda; Johnsen, Geir; Ardelan, Murat Van. (2019) Sea surface microlayer and elemental composition in phaeo-, chloro-, and rhodophytes in winter and spring. Journal of Phycology
    Academic article
  • Mogstad, Aksel Alstad; Johnsen, Geir; Ludvigsen, Martin. (2019) Shallow-Water Habitat Mapping using Underwater Hyperspectral Imaging from an Unmanned Surface Vehicle: A Pilot Study. Remote Sensing
    Academic article
  • Kauko, Hanna Maria; Pavlov, Alexey; Johnsen, Geir; Granskog, Mats; Peeken, Ilka; Assmy, Philipp. (2019) Photoacclimation state of an Arctic underice phytoplankton bloom. Journal of Geophysical Research (JGR): Oceans
    Academic article
  • Bazilchuk, Nancy Reney; Fossum, Trygve Olav; Fragoso, Glaucia Moreira; Ludvigsen, Martin; Johnsen, Geir. (2019) Smart undervannsrobot leter etter plankton. Av N Bazilchuk. Forskning.no. Angående NTNU Entice prosjekt publisert i Science Robotics. Forskning.no
    Popular scientific article
  • Fossum, Trygve Olav; Fragoso, Glaucia Moreira; Davies, Emlyn John; Ullgren, Jenny; Mendes, Renato; Johnsen, Geir. (2019) Toward adaptive robotic sampling of phytoplankton in the coastal ocean. Science robotics
    Academic article
  • Fragoso, Glaucia Moreira; Poulton, Alex James; Pratt, Nicola Jane; Johnsen, Geir; Purdie, Duncan Alastair. (2019) Trait-based analysis of subpolar North Atlantic phytoplankton and plastidic ciliate communities using automated flow cytometer. Limnology and Oceanography
    Academic article
  • Fragoso, Glaucia Moreira; Poulton, Alex J.; Yashayaev, Igor M.; Head, Erica J.H.; Johnsen, Geir; Purdie, Duncan A.. (2018) Diatom biogeography from the Labrador Sea revealed through a trait-based approach. Frontiers in Marine Science
    Academic article
  • Dumke, Ines; Nornes, Stein Melvær; Purser, Autun; Marcon, Yann; Ludvigsen, Martin; Ellefmo, Steinar Løve. (2018) First hyperspectral imaging survey of the deep seafloor: High-resolution mapping of manganese nodules. Remote Sensing of Environment
    Academic article
  • Berge, Jørgen; Johnsen, Geir. (2018) Lysforurensning - enda en kilde til bekymring. Svalbardposten
    Feature article
  • Berge, Jørgen; Johnsen, Geir. (2018) Lysforurensning truer livet i Arktis. Aftenposten Viten
    Feature article
  • Ludvigsen, Martin; Berge, Jørgen; Geoffroy, Maxime; Cohen, Jonathan H.; De La Torre, Pedro R.; Nornes, Stein Melvær. (2018) Use of an autonomous surface vehicle reveals small-scale diel vertical migrations of zooplankton and susceptibility to light pollution under low solar irradiance. Science Advances
    Academic article
  • Ødegård, Øyvind; Mogstad, Aksel Alstad; Johnsen, Geir; Sørensen, Asgeir Johan; Ludvigsen, Martin. (2018) Underwater hyperspectral imaging: a new tool for marine archaeology. Applied Optics
    Academic article
  • Fossum, Trygve Olav; Eidsvik, Jo; Ellingsen, Ingrid H.; Alver, Morten; Fragoso, Glaucia Moreira; Johnsen, Geir. (2018) Information-driven robotic sampling in the coastal ocean. Journal of Field Robotics (JFR)
    Academic article
  • Kauko, Hanna Maria; Olsen, Lasse Mork; Duarte, Pedro; Peeken, Ilka; Granskog, Mats A.; Johnsen, Geir. (2018) Algal colonization of young arctic sea ice in spring. Frontiers in Marine Science
    Academic article
  • Dumke, Ines; Purser, Autun; Marcon, Yann; Nornes, Stein Melvær; Johnsen, Geir; Ludvigsen, Martin. (2018) Underwater hyperspectral imaging as an in situ taxonomic tool for deep-sea megafauna. Scientific Reports
    Academic article
  • Liefmann, Stephanie; Järnegren, Johanna; Johnsen, Geir; Murray, Fiona. (2018) Eco-physiological responses of cold-water soft corals to anthropogenic sedimentation and particle shape. Journal of Experimental Marine Biology and Ecology
    Academic article
  • Geoffroy, Maxime; Berge, Jørgen; Majaneva, Sanna Kristiina; Johnsen, Geir; Langbehn, Tom; Cottier, Finlo Robert. (2018) Increased occurrence of the jellyfish Periphylla periphylla in the European high Arctic. Polar Biology
    Short communication
  • Johnsen, Geir; Norli, Marit; Moline, Mark A.; Robbins, Ian; Quillfeldt, Cecilie von; Sørensen, Kai. (2018) The advective origin of an under-ice spring bloom in the Arctic Ocean using multiple observational platforms. Polar Biology
    Academic article
  • Dumke, Ines; Ludvigsen, Martin; Ellefmo, Steinar Løve; Søreide, Fredrik; Johnsen, Geir; Murton, Bramley J.. (2018) Underwater Hyperspectral Imaging Using a Stationary Platform in the Trans-Atlantic Geotraverse Hydrothermal Field. IEEE Transactions on Geoscience and Remote Sensing
    Academic article
  • Gabrielsen, Tove M.; Johnsen, Geir. (2018) Skogen på Svalbard. Svalbardposten
    Popular scientific article
  • Otterlei, Inger; Johnsen, Geir; Sørensen, Asgeir Johan; Ludvigsen, Martin; Hareide, Nils Roar; Christensen-Dalsgaard, Signe. (2017) 300 000 sjøfugl er forsvunnet fra Runde. Sunnmørsposten
    Interview Journal
  • Johnsen, Geir; Christiansen, Hanne H; Ravolainen, Virve; Reymert, Per Kyrre; Jenssen, Eva Therese; Arlov, Thor Bjørn. (2017) Utfordrende natur og sikkerhet på Svalbard. Svalbardposten
    Feature article
  • Ostaszewska, Kaja; Balazy, Piotr; Berge, Jørgen; Johnsen, Geir; Staven, Robert. (2017) Seabirds during Arctic Polar Night: underwater observations from Svalbard archipelago, Norway. Waterbirds (De Leon Springs, Fla.)
    Academic article
  • Kauko, Hanna Maria; Taskjelle, Torbjørn; Assmy, Philipp; Pavlov, Alexey K.; Mundy, C.J.; Duarte, Pedro. (2017) Windows in Arctic sea ice: light transmission and ice algae in a refrozen lead. Journal of Geophysical Research (JGR): Biogeosciences
    Academic article
  • Berge, Jørgen; Johnsen, Geir. (2017) Kunnskapshull om livet i Arktis i mørketiden. Aftenposten Viten
    Feature article
  • Assmy, Philipp; Fernández-Méndez, Mar; Duarte, Pedro; Meyer, Amelie; Randelhoff, Achim; Mundy, Christopher John. (2017) Leads in Arctic pack ice enable early phytoplankton blooms below snow-covered sea ic. Scientific Reports
    Academic article
  • Mogstad, Aksel Alstad; Johnsen, Geir. (2017) Spectral characteristics of coralline algae: a multi-instrumental approach, with emphasis on underwater hyperspectral imaging. Applied Optics
    Academic article
  • Berge, Jørgen; Johnsen, Geir. (2017) Om bambus, spøkelseskreps og et Arktis i endring. Svalbardposten
    Feature article
  • Berge, Jørgen; Johnsen, Geir. (2017) Superkommunisten. Svalbardposten
    Feature article
  • Berge, Jørgen; Ødegård, Øyvind; Johnsen, Geir. (2016) Opp fra polarnattens mørke. Aftenposten Viten
    Feature article
  • Berge, Jørgen; Ødegård, Øyvind; Johnsen, Geir. (2016) A bitter-sweet symphony. Svalbardposten
    Feature article
  • Berge, Jørgen; Geoffroy, Maxime; Johnsen, Geir; Cottier, Finlo Robert; Bluhm, Bodil; Vogedes, Daniel Ludwig. (2016) Ice-tethered observational platforms in the Arctic Ocean pack ice. IFAC-PapersOnLine
    Academic article
  • Cronin, Heather; Cohen, Jonathan H.; Berge, Jørgen; Johnsen, Geir; Moline, Mark A.. (2016) Bioluminescence as an ecological factor during high Arctic polar night. Scientific Reports
    Academic article
  • Berge, Jørgen; Johnsen, Geir; Ludvigsen, Martin; Cohen, Jonathan. (2016) Design for latskap - men med store muligheter. Svalbardposten
    Feature article
  • Bondø, Tor-Hartvig; Johnsen, Geir; Berge, Jørgen. (2016) Fant yrende liv i polarnatta. VG : Verdens gang
    Popular scientific article
  • Berge, Jørgen; Johnsen, Geir. (2016) Mørkets fyrster med påskrudd lys. Svalbardposten
    Popular scientific article
  • Bazilchuk, Nancy Reney; Leite, Stein Roar; Johnsen, Geir; Kjeken, John; Sørensen, Asgeir Johan; Ludvigsen, Martin. (2016) Bomber og buss på havbunnen. Gemini
    Popular scientific article
  • Haudemann-Andersen, Jørn; Lystad, M S; Johnsen, Geir; Sørensen, Asgeir Johan; Berge, Jørgen. (2016) Blå lys i det kalde dyp. NRK Trøndelag, Nyheter
    Popular scientific article
  • Haugstad, Tor; Erdal, Ivar; Johnsen, Geir; Sørensen, Asgeir Johan; Fjærvik, Nils. (2016) Gründerne mener dette kameraet kan bli det nye ekkoloddet – Ecotone er kandidat til TU Tech Award. Teknisk Ukeblad
    Popular scientific article
  • Bjørgan, Espen Halvorsen; Johnsen, Geir; Kjeken, Jon; Ludvigsen, Martin. (2016) Fant buss på 600 m dybde. Adresseavisen
    Popular scientific article
  • Johnsen, Geir; Ludvigsen, Martin; Sørensen, Asgeir Johan; Aas, Lars Martin Sandvik. (2016) The use of underwater hyperspectral imaging deployed on remotely operated vehicle – methods and applications. IFAC-PapersOnLine
    Academic article
  • Berge, Jørgen; Johnsen, Geir; Ødegård, Øyvind. (2016) Kinderegg i polarnatten. Svalbardposten
    Feature article
  • Donahue, Michelle; Berge, Jørgen; Johnsen, Geir; Ødegård, Øyvind. (2016) The age of humans - living in the anthropocene - "Termites of the sea" found munching wood near Arctic shipwrecks. Smithsonian
    Popular scientific article
  • Bazilchuk, Nancy Reney; Johnsen, Geir; Berge, Jørgen; Sørensen, Asgeir Johan; Ødegård, Øyvind. (2016) Dark lords, werewolves and Indiana Jones in the polar night. Gemini (English edition)
    Interview Journal
  • Krüger, Frida Jørstad; Johnsen, Geir; Kjeken, John; Ludvigsen, Martin. (2016) Gammel buss ble korallrev. NRK Viten
    Popular scientific article
  • Kokkegård, Hanne; Johnsen, Geir; Ludvigsen, Martin; Torre, Pedro De La. (2016) Vitenskab - Bomber fra 2 verdenskrig danner koralrev på 600 m dybde. Danmarks radio
    Popular scientific article
  • Haugstad, Tormod; Erdal, Ivar; Johnsen, Geir. (2016) Kameraet deres «kan bli det nye ekkoloddet». Nå er det norske selskapet i ferd med å lykkes. Teknisk Ukeblad
    Interview Journal
  • Johnsen, Geir. (2016) Yrende liv i Isfjorden. Svalbardposten
    Popular scientific article
  • Aarskog, Karine Nigar; Berge, Jørgen; Johnsen, Geir; Sørensen, Asgeir Johan. (2016) Et stort løft for arktisk forskning (NTNU & UiT). Universitetet i Tromsø
    Article in business/trade/industry journal
  • Berge, Jørgen; Falk-Petersen, Stig; Renaud, Paul E.; Daase, Malin; Geoffroy, Maxime; Johnsen, Geir. (2016) En reise mot Ultima Thule. Svalbardposten
    Popular scientific article
  • Lervik, Frank; Johnsen, Geir; Ludvigsen, Martin; Kjeken, John. (2016) Det ligger flere busser der. Adresseavisen
    Popular scientific article
  • Berge, Jørgen; Johnsen, Geir; Ødegård, Øyvind. (2016) Mark spiser opp vrak på havbunnen. Fiskaren
    Popular scientific article
  • Kintisch, Eli; Berge, Jørgen; Last, Kim; Cohen, Jonathan; Johnsen, Geir. (2016) Voyage into darkness . Science
    Interview Journal
  • Bazilchuk, Nancy Reney; Johnsen, Geir; Berge, Jørgen; Ludvigsen, Martin; Sørensen, Asgeir Johan; Ødegård, Øyvind. (2016) Mørkets fyrster, varulver og Indiana Jones. Gemini
    Popular scientific article
  • Berge, Jørgen; Renaud, Paul E.; Johnsen, Geir; Darnis, Gerald; Geoffroy, Maxime; Daase, Malin. (2016) I grenselandet (mellom Tull og Thule). Svalbardposten
    Popular scientific article
  • Førde, Henny; Forbord, Silje; Handå, Aleksander; Fossberg, Julia; Arff, Johanne; Johnsen, Geir. (2016) Development of bryozoan fouling on cultivated kelp (Saccharina latissima) in Norway. Journal of Applied Phycology
    Academic article
  • Nilssen, Ingunn; Dos Santos, Francisco; Coutinho, Ricardo; Gomes, Natalia; Cabral, Marcelo M.; Eide, Ingvar. (2015) Assessing the potential impact of water-based drill cuttings on deep water calcareous red algae using species specific impact categories and measured oceanographic and discharge data. Marine Environmental Research
    Academic article
  • Nilssen, Ingunn; Santos dos, Francisco; Coutinho, Ricardo; Gomes, Natalia; Cabral Montenegro, Marcelo; Eide, Ingvar. (2015) Assessing the potential impact of water-based drill cuttings on deep-water calcareous red algae using species specific impact categories and measured oceanographic and discharge data. Marine Environmental Research
    Academic article
  • Berge, Jørgen; Johnsen, Geir; Sørensen, Asgeir Johan; Nilssen, Ingunn. (2015) Enabling technology for Arctic research. Pan European Networks: Science and Techology Magazine
    Academic literature review
  • Rodriguez, Francisco; Garrido, J.L.; Sabrino, C; Johnsen, Geir; Riobo, P; Franco, J. (2015) Divinyl chlorophyll a in the marine eukaryotic protist Alexandrium ostenfeldii (Dinophyceae). Environmental Microbiology
    Academic article
  • Nilssen, Ingunn; Ødegård, Øyvind; Sørensen, Asgeir Johan; Johnsen, Geir; Moline, Mark A.; Berge, Jørgen. (2015) Integrated environmental mapping and monitoring, a methodological approach to optimise knowledge gathering and sampling strategy. Marine Pollution Bulletin
    Academic article
  • Cohen, Jonathan H.; Berge, Jørgen; Moline, Mark A.; Sørensen, Asgeir Johan; Last, Kim; Falk-Petersen, Stig. (2015) Is ambient light during the high Arctic polar night sufficient to act as a visual cue for zooplankton?. PLOS ONE
    Academic article
  • Berge, Jørgen; Renaud, Paul; Darnis, Gérald; Cottier, Finlo; Last, Kim; Gabrielsen, Tove M.. (2015) In the dark: a review of ecosystem processes during the Arctic polar night. Progress in Oceanography
    Academic article
  • Berge, Jørgen; Daase, Malin; Renaud, Paul; Ambrose, William G. Jr.; Darnis, Gérald; Last, Kim S. (2015) Unexpected levels of biological activity during the polar night offer new perspectives on a warming Arctic. Current Biology
    Academic article
  • Pettersen, Ragnhild; Johnsen, Geir; Bruheim, Per; Andreassen, Trygve. (2014) Development of hyperspectral imaging as a bio-optical taxonomic tool for pigmented marine organisms. Organisms Diversity & Evolution
    Academic article
  • Valle, Kristin Collier; Nymark, Marianne; Aamot, Inga; Hancke, Kasper; Winge, Per; Andresen, Kjersti. (2014) System responses to equal doses of photosynthetically usable radiation of blue, green, and red light in the marine diatom Phaeodactylum tricornutum. PLOS ONE
    Academic article
  • Ludvigsen, Martin; Johnsen, Geir; Sørensen, Asgeir Johan; Lågstad, Petter Arthur; Ødegård, Øyvind. (2014) Scientific Operations Combining ROV and AUV in the Trondheim Fjord. Marine Technology Society journal
    Academic article
  • Johnsen, Geir; Candeloro, Mauro; Berge, Jørgen; Moline, Mark A.. (2014) Glowing in the dark: Discriminating patterns of bioluminescence from different taxa during the Arctic polar night. Polar Biology
    Academic article
  • Hansen, Ingrid; Pettersen, Ragnhild; Beuchel, Frank; Cochrane, Sabine; Frantzen, marianne; Ekehaug, Stefan. (2014) Underwater hyperspectral imaging (UHI) for environmental mapping and monitoring of seabed habitats. Ocean Optics
    Abstract
  • Cohen, Jonathan; Cronin, Heather; Moline, Mark A.; Berge, Jørgen; Johnsen, Geir; Sørensen, Asgeir Johan. (2014) Are krill eyes useful in the high Arctic polar night?. Ocean Optics
    Abstract
  • Johnsen, Geir; Ekehaug, Stefan; Hansen, Ingrid; Sørensen, Asgeir Johan. (2014) The use of underwater hyperspectral imaging deployed on remotely operated vehicles to identify, map and monitor bio-geo-chemical objects of interest. Ocean Optics
    Abstract
  • Aamot, Inga; Pokrzywinski, Kaytee; Johnsen, Geir; Berge, Jørgen; Sørensen, Asgeir Johan. (2014) Light Climate and Status of the Photosynthetic Machinery in Macroalgae in the Polar Night. Ocean Optics
    Abstract
  • Nornes, Stein Melvær; Candeloro, Mauro; Ødegård, Øyvind; Johnsen, Geir; Sørensen, Asgeir Johan. (2014) Photomosaic camera as simultaneous data collector and navigation aid on unmanned underwater vehicles. Ocean Optics
    Abstract
  • Nilssen, Ingunn; Ødegård, Øyvind; Johnsen, Geir; Sørensen, Asgeir Johan; Berge, Jørgen; Nornes, Stein Melvær. (2014) Integrated environmental monitoring; a methodological approach to optimise knowledge gathering and sampling strategy. Ocean Optics
    Abstract
  • Johnsen, Geir; Candeloro, Mauro; Berge, Jørgen; Moline, Mark A.. (2014) Erratum to: Glowing in the dark: discriminating patterns of bioluminescence from different taxa during the Arctic polar night. Polar Biology
    Errata
  • Berge, Jørgen; Cottier, Finlo; Varpe, Øystein; Renaud, Paul; Falk-Petersen, Stig; Kwasniewski, Sawomir. (2014) Arctic complexity: A case study on diel vertical migration of zooplankton. Journal of Plankton Research
    Academic article
  • Hancke, Kasper; Hovland, Erlend Kjeldsberg; Volent, Zsolt; Pettersen, Ragnhild; Johnsen, Geir; Moline, Mark A.. (2014) Optical properties of CDOM across the Polar Front in the Barents Sea: Origin, distribution and significance. Journal of Marine Systems
    Academic article
  • Hovland, Erlend Kjeldsberg; Hancke, Kasper; Alver, Morten; Drinkwater, Kennneth F.; Høkedal, Jo; Johnsen, Geir. (2014) Optical impact of an Emiliania huxleyi bloom in the frontal region of the Barents Sea. Journal of Marine Systems
    Academic article
  • Båtnes, Anna Solvang; Miljeteig, Cecilie; Berge, Jørgen; Greenacre, Michael; Johnsen, Geir. (2013) Quantifying the light sensitivity of Calanus spp. during the polar night: potential for orchestrated migrations conducted by ambient light from the sun, moon, or aurora borealis. Polar Biology
    Academic article
  • Berge, Jørgen; Johnsen, Geir; Falk-Pettersen, Stig. (2013) Mørkets hemmeligheter. Svalbardposten
    Popular scientific article
  • Nymark, Marianne; Valle, Kristin Collier; Hancke, Kasper; Winge, Per; Andresen, Kjersti; Johnsen, Geir. (2013) Molecular and photosynthetic responses to prolonged darkness and subsequent acclimation to re-illumination in the diatom Phaeodactylum tricornutum. PLOS ONE
    Academic article
  • Hovland, Erlend Kjeldsberg; Dierssen, Heidi; Ferreira, Ana Sofia; Johnsen, Geir. (2013) Dynamics regulating major trends in Barents Sea temperatures and subsequent effect on remotely sensed particulate inorganic carbon. Marine Ecology Progress Series
    Academic article
  • Berge, Jørgen; Båtnes, Anna Solvang; Johnsen, Geir; Blackwell, Susan; Moline, Mark A.. (2012) Bioluminescence in the high Arctic during the polar night. Marine Biology
    Academic article
  • Gabrielsen, Tove M; Quillfeldt, Cecilie von; Johnsen, Geir; Berge, Jørgen. (2012) Varm vinter, sen vår i fjorden. Svalbardposten
    Reader opinion piece
  • Elde, Anette; Pettersen, Ragnhild; Bruheim, Per; Järnegren, Johanna; Johnsen, Geir. (2012) Pigmentation and Spectral Absorbance Signatures in Deep-Water Corals from the Trondheimsfjord, Norway. Marine Drugs
    Academic article
  • Thoen, Hanne Halkinrud; Johnsen, Geir; Berge, Jørgen. (2011) Pigmentation and spectral absorbance in the deep-sea arctic amphipods Eurythenes gryllus and Anonyx sp. Polar Biology
    Academic article
  • Volent, Zsolt; Johnsen, Geir; Hovland, Erlend Kjeldsberg; Folkestad, Are; Olsen, Lasse Mork; Tangen, Karl. (2011) Improved monitoring of phytoplankton bloom dynamics in a Norwegian fjord by integrating satellite data, pigment analysis, and Ferrybox data with a coastal observation network. Journal of Applied Remote Sensing
    Academic article
  • Jouenne, Fabien; Eikrem, Wenche; Le Gall, F; Marie, Dominique; Johnsen, Geir; Vaulot, Daniel. (2011) Prasinoderma singularis sp. nov. (Prasinophyceae, Chlorophyta), a Solitary Coccoid Prasinophyte from the South-East Pacific Ocean. Protist
    Academic article
  • Pettersen, Ragnhild; Johnsen, Geir; Berge, Jørgen; Hovland, Erlend Kjeldsberg. (2011) Phytoplankton chemotaxonomy in waters around the Svalbard archipelago reveals high amounts of Chl b and presence of gyroxanthin-diester. Polar Biology
    Academic article
  • Thoen, Hanne Halkinrud; Johnsen, Geir; Berge, Jørgen. (2010) Pigmentation and spectral absorbance in the deep-sea arctic amphipods Eurythenes gryllus and Anonyx sp. Polar Biology
    Academic article
  • Aamot, Inga; Berge, Jørgen; Hancke, Kasper; Johnsen, Geir; Moline, Mark; Schofield, Oscar. (2010) NORUS - Technology Development for Marine Monitoring and Ocean Observation:An North America-Norway educational program. http://ipy-osc.no/abstract/
    Abstract
  • Johnsen, Geir; Søreide, Fredrik. (2010) Underwater hyperspectral imaging of marine mineral deposits. Underwater Mining meeting Institute (UMI)
    Abstract
  • Berge, Jørgen; Cottier, Finlo; Last, Kim S.; Varpe, Øystein; Leu, Eva; Søreide, Janne. (2009) Diel vertical migration of Arctic zooplankton during the polar night. Biology Letters
    Academic article
  • Nymark, Marianne; Valle, Kristin Collier; Brembu, Tore; Winge, Per; Hancke, Kasper; Andresen, Kjersti. (2009) An integrated analysis of molecular acclimation to high light in the marine diatom Phaeodactylum tricornutum. PLOS ONE
    Academic article
  • Berge, Jørgen; Lønne, Ole Jørgen; Renaud, Paul; Johnsen, Geir; Gulliksen, Bjørn; Varpe, Øystein. (2009) Polartorsken - vil den bli utkonkurrert av sørlige fiskearter?. Svalbardposten
    Popular scientific article
  • Evertsen, Jussi; Johnsen, Geir. (2009) In vivo and in vitro differences in chloroplast functionality in the two north Atlantic sacoglossans (Gastropoda, Opisthobranchia) Placida dendritica and Elysia viridis. Marine Biology
    Academic article
  • Volent, Z; Johnsen, Geir; Sigernes, Fred. (2009) Microscopic hyperspectral imaging used as a bio-optical taxonomic tool for micro- and macroalgae. Applied Optics
    Academic article
  • Hancke, Torunn Beate; Hancke, Kasper; Johnsen, Geir; Sakshaug, Egil. (2008) Rate of O2 production derived from pulse-amplitude-modulated fluorescence: Testing three biooptical approaches against measured O2-production rate. Journal of Phycology
    Academic article
  • Bredholt, Harald; Fjærvik, Espen; Johnsen, Geir; Zotchev, Sergey. (2008) Actinomycetes from sediments in the Trondheim Fjord, Norway: Diversity and biological activity. Marine Drugs
    Academic article
  • Bakken, Torkild; Evertsen, Jussi; Johnsen, Geir. (2008) Vitenskapelig dykking - behov for endringer i forskriften. Dykkenytt : informasjonsorgan for dykkeindustrien
    Article in business/trade/industry journal
  • Hancke, Kasper; Hancke, Torunn Beate; Olsen, Lasse Mork; Johnsen, Geir; Glud, RN. (2008) Temperature effects on microalgal photosynthesis-light responses measured by O2 production, pulse-amplitude-modulated fluorescence, and C-14 assimilation. Journal of Phycology
    Academic article
  • Hovland, Erlend Kjeldsberg; Johnsen, Geir; Moline, Mark. (2008) Combined use of AUV and hyperspectral imaging to mapping sea-surface and macroalgae. Ocean Optics
    Abstract
  • Cibic, Tamara; Blasutto, Oriana; Hancke, Kasper; Johnsen, Geir. (2007) Microphytobenthic species composition, pigment concentration, and primary production in sublittoral sediments of the Trondheimsfjord (Norway). Journal of Phycology
    Academic article
  • Evertsen, Jussi; Burghardt, Ingo; Johnsen, Geir; Wägele, Heike. (2007) Retention of functional chloroplasts in some sacoglossans from the Indo-Pacific and Mediterranean. Marine Biology
    Academic article
  • Ludvigsen, Martin; Sortland, Bjørn; Johnsen, Geir; Singh, Hanumant. (2007) Applications of Geo-Referenced Underwater Photo Mosaics in Marine Biology and Archaeology. Oceanography
    Academic article
  • Johnsen, Geir; Sakshaug, Egil. (2007) Biooptical characteristics of PSII and PSI in 33 species (13 pigment groups) of marine phytoplankton, and the relevance for pulse-amplitude-modulated and fast-repetition-rate fluorometry. Journal of Phycology
    Academic article
  • Edvardsen, B; Eikrem, W; Shalchian-Tabrizi, K; Riisberg, I; Johnsen, Geir; Naustvoll, L. (2007) Verrucophora farcimen gen. et sp nov (Dictyochophyceae, Heterokonta) - A bloom-forming ichthyotoxic flagellate from the Skagerrak, Norway. Journal of Phycology
    Academic article
  • Johnsen, Geir. (2007) Arctic Life: Bridging ecosystem function using remote sensing technologies. Svalbard Science Forum
    Popular scientific article
  • Carlsen, BP; Johnsen, Geir; Berge, Jørgen; Kuklinski, P. (2007) Biodiversity patterns of macro-epifauna on different lamina parts of Laminaria digitata and Saccharina latissima collected during spring and summer 2004 in Kongsfjorden, Svalbard. Polar Biology
    Academic article
  • Volent, Z; Johnsen, Geir; Sigernes, Fred. (2007) Kelp forest mapping by use of airborne hyperspectral imager. Journal of Applied Remote Sensing
    Academic article
  • Berge, Jørgen; Johnsen, Geir; Nilsen, Frank; Nilsen, Frank; Gulliksen, Bjørn; Slagstad, Dag. (2006) The Mytilus edulis population in Svalbard: how and why. Marine Ecology Progress Series
    Editorial
  • Berge, Jørgen; Johnsen, Geir; Nilsen, Frank; Gulliksen, Bjørn; Slagstad, Dag; Pampanin, Daniella. (2006) The Mytilus edulis population in Svalbard: how and why. Marine Ecology Progress Series
    Academic article
  • Olsen, Lasse Mork; Öztürk, M.; Sakshaug, Egil; Johnsen, Geir. (2006) Photosynthesis-induced phosphate precipitation in seawater: ecological implications for phytoplankton. Marine Ecology Progress Series
    Academic article
  • Rodriguez, F; Chauton, Matilde Skogen; Johnsen, Geir; Andresen, Kjersti; Olsen, Lasse Mork; Zapata, M.. (2006) Photoacclimation in phytoplankton: implications for biomass estimates, pigment functionality and chemotaxonomy. Marine Biology
    Academic article
  • Johnsen, Geir. (2006) Warming Arctic sees return of blue mussels after 1000 years. National Geographic
    Popular scientific article
  • Onstad, L; Evertsen, Jussi; Johnsen, Geir. (2006) Snegle på solceller. Gemini
    Popular scientific article
  • Berge, Jørgen; Johnsen, Geir; Nilsen, Frank; Gulliksen, Bjørn; Slagstad, Dag. (2005) Ocean temperature oscillations enable reappearance of blue mussels Mytilus edulis in Svalbard after 1000 year absence. Marine Ecology Progress Series
    Academic article
  • Berge, J; Johnsen, Geir; Nilsen, F; Gulliksen, B; Slagstad, D. (2005) Ocean temperature oscillations causes the reappearance of blue mussels in Svalbard after 1000 years of absence. Marine Ecology Progress Series
    Academic article
  • Bordvik, Hans Otto; Johnsen, Geir. (2005) “En glupsk nellik”. NEWTON websider (NRK)
    Popular scientific article
  • Indergaard, M; Nordtvedt, M; Johnsen, Geir. (2005) Satellittmålinger for miljøet (SISCAL project, NTNU, IBI). Gemini
    Popular scientific article
  • Bordvik, Hans Otto; Johnsen, Geir. (2005) “Forskning og foto under vann”. NEWTON websider (NRK)
    Popular scientific article
  • Burghardt, Ingo; Evertsen, Jussi; Johnsen, Geir; Wägele, Heike. (2005) Solar powered seaslugs - Mutualistic symbiosis of aeolid nudibranchia (Mollusca, Gastropoda, Opisthobranchia) with Symbiodinium. Symbiosis
    Academic article
  • Fossmark, Reidar; Johnsen, Geir; Waldum, Helge; Johannesen, Eli Marie. (2005) Rebound acid hypersecretion after long-term inhibition of gastric acid secretion. Alimentary Pharmacology and Therapeutics
    Academic article
  • Chauton, Matilde Skogen; Tilstone, Gavin; Legrand, Catherine; Johnsen, Geir. (2004) Changes in pigmentation, bio-optical characteristics and photophysiology, during phytoflagellate succession in mesocosms. Journal of Plankton Research
    Academic article
  • Johansen, Torunn Beate; Johnsen, Geir. (2003) SISCAL prototype evaluation document. www.siscal.net. Satellite-based Information System on Coastal Areas and Lakes. IST 2000
    Academic article
  • Johansen, Torunn Beate; Johnsen, Geir. (2003) SISCAL End User Requirement evaluation document. www.siscal.net. Satellite-based Information System on Coastal Areas and Lakes. IST 2000
    Academic article
  • Chauton, Matilde Skogen; Optun, Odd Inge; Bathen, F. T; Volent, Z.; Gribbestad, Ingrid S.; Johnsen, Geir. (2003) HR MAS 1H NMR spectroscopy analysis of whole cells of marine microalgae. Marine Ecology Progress Series
    Academic article
  • Figueroa, F. L.; Escassi, L.; Perez-Rodriguez, E.; Korbee, N.; Johnsen, Geir. (2003) Effects of the irradiance in the short-term on accumulation of mycosporine like amino acids in sun and shade species of the red algal genus Porphyra. Photochemistry and Photobiology
    Academic article
  • Gileptis, Laura; Johnsen, Geir; Moxness, Helge; Norwich, Inger; Vangen, Steffen. (2002) Modul for mønstergjenkjenning/klassifisering i DynamicImager ved bruk av backpropagation-algoritmen. Piksel'n : Organ for NOBIM (Norsk forening for bildebehandling og mønstergjenkjenning)
    Academic article
  • Millie, David; Schofield, Oscar; Kirkpatrick, Gary J.; Johnsen, Geir; Evens, Tim J.. (2002) Using absorbance and fluorescence spectra to discriminate microalgae. European journal of phycology
    Academic article
  • Johnsen, Geir; Børsheim, Knut Yngve; Johansen, Torunn Beate. (2002) Production and mortality of phytoplankton and sea-ice microalgae in the southern ocean. Rapportserie (Norsk polarinstitutt)
    Academic article
  • Wägele, Heike; Johnsen, Geir. (2001) New results on histology and photosynthetic performance of solar-powered� opisthobranchs (Mollusca, Gastropoda, Opisthobranchia) containing symbiotic chloroplasts or zooxanthellae. Organisms Diversity & Evolution
    Academic article
  • Legrand, Catherine; Johnsen, Geir; Graneli, Edna; Sakshaug, Egil. (2001) (Proceedings of the 9th International conference on Harmful Algal Blooms. Hobart, Tasmania, 7-11 February 2000.) Effect of polyamines on growth and toxicity of Chrysochromulina leadbeateri, Haptophytae. Phycologia
    Academic article
  • Graneli, Edna; Legrand, Catherine; Carlsson, Per; Johnsen, Geir; Maestrini, Serge Y.; Reichelt, Michael. (2001) (Proceedings of the 9th International conference on Harmful Algal Blooms. Hobart, Tasmania, 7-11 February 20). Structuration of marine phytoplankton communities subjected to different levels of N, P and Si limitation in a mesocosm experiment (summary paper). Phycologia
    Academic article
  • Legrand, Catherine; Johansson, Niclas; Johnsen, Geir; Børsheim, Knut Yngve; Graneli, Edna. (2001) Phagotrophy and toxicity in the photosynthetic Prymnesium patelliferum (Haptophyte). Limnology and Oceanography
    Academic article
  • Seppala, J; Johnsen, Geir; Babichenko, S; Leeben, A; Poryvkina, L; Shalapyonok, [Mangler fornavn]. (1998) In vivo light absorption by photosynthetic and photoprotective algal pigments: Methodology and the effects of light acclimation and nutrient limitation. Report Series in Geophysics
    Academic article
  • Johnsen, Geir; Dalløkken, Runar; Aure, J; Skjoldal, H. R. (1998) Photophysiology and environmental conditions during a toxic bloom of Chrysochromulina leadbeateri (Prymnesiophyceae). International symposium on Harmful Algal Blooms
    Academic article
  • Johnsen, Geir; Eikrem, W.; Dalløkken, R.; Aure, J.; Skjoldal, H. R.. (1998) Physiology and environmental conditions during a toxic blooms of Chrysochromulina leadbeateri Prymnesiophyceae. Journal of Phycology
    Academic article
  • Grzymski, J.; Johnsen, Geir; Sakshaug, Egil. (1997) The significance of intracellular self-shadingon the bio-optical properties of brown, red and green macroalgal species. Journal of Phycology
    Academic article
  • Johnsen, Geir; Prezelin, B. B.; Jovine, R. V. M.. (1997) Fluorescence excitation spectra and light utiliation in two red tide dinoflagellates. Limnology and Oceanography
    Academic article
  • Millie, D.; Schofield, O. M.; Kirkpatrick, G. J.; Johnsen, Geir; Tester, P. A.; Vinyard, B. T.. (1997) Phytoplankton pigments and absorption spectra as potential bio-markers for harmful algal blooms: A case study of the Florida red-tide dinoflagellat Gymnodinium breve. Limnology and Oceanography
    Academic article
  • Grzymski, J.; Johnsen, Geir; Sakshaug, Egil. (1997) The significance of intracellular self-shading on the bio-optical properties of brown, red and green macroalgal species. Journal of Phycology
    Academic article
  • Vernet, M.; Mitchell, B.G.; Sakshaug, Egil; Johnsen, Geir; Iturriaga, R.; Wassmann, P.. (1996) Evidence for a novel pigment with in vivo absorption maximum at 708 nm associated with Phaeocystis cf. pouchetii blooms. Marine Ecology Progress Series
    Academic article
  • Schofield, O.; Prezelin, B. B.; Johnsen, Geir. (1996) Wavelength-dependency of maximum quantum yield of carbon fixation for two red tide dinoflagellates, Heterocapsa pygmaea and prorocentrum minimum. Journal of Phycology
    Academic article
  • Johnsen, Geir; Sakshaug, Egil. (1996) Light harvesting in bloom-forming marine phytoplankton: Species-specifity and photoacclimation,. Scientia Marina
    Academic article
  • Johnsen, Geir; Volent, Z; Tangen, K; Sakshaug, Egil. (1996) Time-series of potential toxic phytoplankton blooms in North European waters in 1993 using the SEAWATCH-Europe buoy system. EOS
    Academic article
  • Vernet, M.; Mitchell, B. G.; Sakshaug, Egil; Johnsen, Geir; Iturriaga, R.; Wassmann, P.. (1996) Evidence for a novel pigment with in vivo absorption maximum at 708 nm associated with Phaeocystis sp. blooms. Marine Ecology Progress Series
    Academic article
  • Millie, D; Shofield, O. M; Kirkpatrick, G. J; Tester, P. A; Johnsen, Geir. (1996) Using bio-optical characterisics as bio-markers for harmful algal blooms: A case study of the Florida red-tide dinoflagellate,. EOS
    Academic article
  • Johnsen, Geir; Sakshaug, Egil. (1995) Light harvesting in bloom-forming marine phytoplankton: species-specificity and photoadaption. Scientia Marina
    Academic article
  • Egeland, E.; Johnsen, Geir; Eikrem, W.; Liaaen-Jensen, S.; Throndsen, J.. (1995) The pigments of Bathycoccus prasinos. Journal of Phycology
    Academic article
  • Jovine, R. V.; Johnsen, Geir; Prezelin, B. B.. (1995) Isolation of membrane bound chlorophyll a-chlorofhyll c binding light harvesting complexes from the dinoflagellates heterocapsa pygmaea and Prorocentrum minimum. Photosynthesis Research
    Academic article
  • Johnsen, Geir; Nelson, N. B.; Jovine, R. V. M.; Prezelin, B. B.. (1994) Chromoprotein- and pigment-dependent modeling of spectral light absorption in two dinoflagellates, Prorocentrum minimum and Heterocapsa pygmaea. Marine Ecology Progress Series
    Academic article
  • Jovine, R. V; Johnsen, Geir; Prezelin, B. B. (1994) Photoadaptation of Prorocentrum minimum and Heterocapsa pygmaea (Dinoflagellates): Chromoprotein changes and the consequenses for spectral absorption. EOS
    Academic article
  • Jovine, R. V.; Schofield, O.; Johnsen, Geir; Prezelin, B. B.. (1994) Photoacclimatory differences in the light-harvesting complex of the bloom forming dinoflagellates Heterocapsa pygmaea and Prorocentrum minimum. Journal of Phycology
    Academic article
  • Johnsen, Geir; Samset, O.; Granskog, L.; Sakshaug, Egil. (1994) In vivo absorption characteristics in 10 classes of phytoplankton: Taxonomic characteristics and responses to photoadaption by means of discriminant and HPLC analysis. Marine Ecology Progress Series
    Academic article
  • Johnsen, Geir; Sakshaug, Egil. (1993) Bio-optical characteristics and photoadaptive responses in the toxic and bloomforming dinoflagellates Gyrodinium aureolum, Gymnodinium galatheanum two strains of Prorocentrum minium. Journal of Phycology
    Academic article
  • Gilstad, Mona; Johnsen, Geir; Sakshaug, Egil. (1993) Photosynthetic parameters, pigment composition and respiration rates of the marine diatom Skeletonema costatum grown in continuous light and a 12:1 light-dark cycle. Journal of Plankton Research
    Academic article
  • Volent, Zsolt; Johnsen, Geir. (1993) Presentation of an optical sensor-"OPTISENS" designed for Eulerian measurements of Phytoplankton on a buoy. Underwater light measurements. Proceedings from International Symposium on high latitude optics.
    Academic article
  • Johnsen, Geir; Samset, Oddgeir; Zsolt, Volent. (1992) Bio-optical characteristicts of phytoplankton in relation to remote sensing. ABOOS (Autonomous Bio-Optical Observing Systems) Scientific Symposium : Abstracts
    Academic article
  • Volent, Zsolt; Johnsen, Geir. (1992) Presentation of an optical sensor-"OPTISENS" designed for Eulerian measurements of Phytoplankton on a moored buoy. ABOOS (Autonomous Bio-Optical Observing Systems) Scientific Symposium : Abstracts
    Academic article
  • Johnsen, Geir; Sakshaug, Egil; Vernet, Maria. (1992) Pigment composition, spectral characteriation and photosynthetic parameters in Chrysochromulina polylepis. Marine Ecology Progress Series
    Academic article
  • Johnsen, Geir. (1991) Proceedings from a scientific working meeting. Fisken og Havet
    Academic article
  • Johnsen, Geir; Hegseth, Else Nøst. (1991) Photoadaptation of sea-ice microalgae in the Barents Sea. Polar Biology
    Academic article
  • Johnsen, Geir. (1991) Identification of Chrysochromulina leadbeateri by means of remote sensing. Fisken og Havet
    Academic article
  • Sakshaug, Egil; Johnsen, Geir; Samset, Oddgeir; Zsolt, Volent. (1991) Identification of phytoplankton blooms by means of remote sensing. Environment Northern Seas
    Academic article
  • Sakshaug, Egil; Johnsen, Geir; Andresen, Kjersti; Vernet, Maria. (1991) Modeling of light-dependent algal photosynthesis and growth: Experiments with the Barents Sea diatoms Thalassiosira nordensskioeldii and Chaetocero furcellatus. Deep-Sea Research Part II: Topical Studies in Oceanography
    Academic article

Artistic productions

  • Snyder, Mike; Berge, Jørgen; Johnsen, Geir; Mckee, David. (2021) “Into the dark” documentary by Mike Snyder following Jørgen Berge (UiT), Geir Johnsen (NTNU) and David McKee (Uni Strathclyde) during Polar Night marine ecology work. .
    Film

Books

  • Berge, Jørgen; Johnsen, Geir; Cohen, Jonathan H.. (2020) Polar night marine ecology - life and light in the dead of night. Springer Advances in Polar Ecology (0)
    Academic anthology/Conference proceedings
  • Roy, Suzanne; Llewellyn, Carole; Egeland, Einar Skarstad; Johnsen, Geir. (2012) Phytoplankton Pigments: Characterization, Chemotaxonomy and Applications in Oceanography. Cambridge University Press Cambridge Environmental Chemistry Series (2012)
    Academic anthology/Conference proceedings
  • Roy, Suzanne; Llewellyn, Carole; Egeland, Einar Skarstad; Johnsen, Geir. (2011) Phytoplankton pigments : characterization, chemotaxonomy and applications in oceanography. Cambridge University Press Cambridge Environmental Chemistry Series (2011)
    Academic anthology/Conference proceedings
  • Sakshaug, Egil; Johnsen, Geir; Kovacs, Kit M.. (2009) Ecosystem Barents Sea. Tapir Akademisk Forlag Tapir Akademisk Forlag
    Non-fiction book
  • Sakshaug, Egil; Johnsen, Geir; Kovacs, Kit. (2009) Ecosystem Barents Sea. Tapir Akademisk Forlag Tapir Akademisk Forlag
    Academic anthology/Conference proceedings
  • Sakshaug, E.; Johnsen, Geir; Kovacs, Kit. (2009) Ecosystem Barents Sea. Tapir Akademisk Forlag Tapir Akademisk Forlag
    Textbook
  • Sakshaug, Egil; Johnsen, Geir. (2005) Algal cultures, Analogues of Blooms and Applications. Multi-Science Publishing Multi-Science Publishing
    Academic anthology/Conference proceedings
  • Syvertsen, E.; Hegseth, E; Johnsen, Geir; Sakshaug, Egil; Gulliksen, B; Lønne, O. J. (1992) Livet i isen (The life in the ice). In Økosystem Barentshavet. [Mangler utgivernavn]
    Non-fiction book
  • Sakshaug, Egil; Kristiansen, S; Syvertsen, E; Eilertsen, H. C; Gilstad, M; Hegseth, E. N. (1992) Planktonalger (Phytoplankton). In Økosystem Barentshavet. [Mangler utgivernavn]
    Non-fiction book

Part of book/report

  • Zolich, Artur Piotr; Faltynkova, Andrea; Johnsen, Geir; Johansen, Tor Arne. (2022) Portable Catamaran Drone - an uncrewed sampling vehicle for micro-plastics and aquaculture research.
    Academic chapter/article/Conference paper
  • Berge, Jørgen; Johnsen, Geir. (2020) Life and Light at the Dead of Night. Springer
    Academic chapter/article/Conference paper
  • Cohen, Jonathan H.; Berge, Jørgen; Moline, Mark A.; Johnsen, Geir; Zolich, Artur Piotr. (2020) Light in the Polar Night. Springer
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Mogstad, Aksel Alstad; Berge, Jørgen; Cohen, Jonathan H.. (2020) Operative Habitat Mapping and Monitoring in the Polar Night. Springer
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Leu, Eva; Gradinger, Rolf. (2020) Marine Micro- and Macroalgae in the Polar Night. Springer
    Academic chapter/article/Conference paper
  • Berge, Jørgen; Johnsen, Geir; Cohen, Jonathan H.. (2020) Introduction. Springer
    Introduction
  • Pavlov, Alexey K.; Leu, Eva; Hanelt, Dieter; Bartsch, Inka; Karsten, Ulf; Hudson, Stephen. (2019) The Underwater Light Climate in Kongsfjorden and Its Ecological Implications. Springer
    Academic chapter/article/Conference paper
  • Zolich, Artur Piotr; De La Torre, Pedro R.; Rodwell, Shane; Geoffroy, Maxime; Johnsen, Geir; Berge, Jørgen. (2018) An ice-tethered buoy for fish and plankton research. IEEE conference proceedings
    Academic chapter/article/Conference paper
  • Ludvigsen, Martin; Thorsnes, Terje; Hansen, Roy Edgar; Sørensen, Asgeir Johan; Johnsen, Geir; Lågstad, Petter Arthur. (2015) Underwater vehicles for environmental management in coastal areas. IEEE conference proceedings
    Academic chapter/article/Conference paper
  • Ødegård, Øyvind; Ludvigsen, Martin; Johnsen, Geir; Sørensen, Asgeir Johan; Ekehaug, Stefan; Dukan, Fredrik. (2014) Managing data from multiple sensors in an interdisciplinary research cruise. Amsterdam University Press
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Volent, Zsolt; Dierssen, Heidi; Pettersen, Ragnhild; Ardelan, Murat Van; Søreide, Fredrik. (2013) Underwater hyperspectral imagery to create biogeochemical maps of seafloor properties. Woodhead Publishing Limited
    Academic chapter/article/Conference paper
  • Ludvigsen, Martin; Johnsen, Geir; Lågstad, Petter Arthur; Sørensen, Asgeir Johan; Ødegård, Øyvind. (2013) Scientific operations combining ROV and AUV in the Trondheim Fjord. IEEE conference proceedings
    Academic chapter/article/Conference paper
  • Brunet, Christophe; Johnsen, Geir; Lavaud, Johan; Roy, Suzanne. (2011) Pigments and photoacclimation processes. Cambridge University Press
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Bricaud, Annick; Nelson, Norman; Prézelin, Barbara; Bidigare, Robert. (2011) In vivo bio-optical properties of phytoplankton pigments. Cambridge University Press
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Moline, Mark; Pettersson, Lasse H.; Pinckney, J. L.; Pozdnyakov, Dmitry; Egeland, Einar Skarstad. (2011) Optical monitoring of phytoplankton bloom pigment signatures. Cambridge University Press
    Academic chapter/article/Conference paper
  • Llewellyn, Carole A.; Roy, Suzanne; Johnsen, Geir; Egeland, Einar Skarstad; Chauton, Matilde ; Hallegraeff, Gustaff. (2011) Perspectives on future directions. Cambridge University Press
    Academic chapter/article/Conference paper
  • Roy, Suzanne; Llewellyn, Carole; Egeland, Einar Skarstad; Johnsen, Geir. (2011) Preface. Cambridge University Press
    Foreword
  • Roy, Suzanne; Llewellyn, Carole; Egeland, Einar Skarstad; Johnsen, Geir. (2011) Acknowledgements. Cambridge University Press
    Other
  • Johnsen, Geir; Volent, Z; Sakshaug, E.; Sigernes, Fred; Pettersson, L.H.. (2009) Remote sensing in the Barents Sea. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Sakshaug, E.; Johnsen, Geir; Kristiansen, Svein; Quillfeldt, C.v.; Rey, F.; Slagstad, D.. (2009) Phytoplankton and primary production. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Sakshaug, E.; Johnsen, Geir; Volent, Z. (2009) Light. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Quillfeldt, C.v.; Hegseth, E.N.; Johnsen, Geir; Sakshaug, E.; Syvertsen, E.E.. (2009) Ice algae. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • von Quillfeldt, Cecilie H.; Hegseth, Else Nøst; Johnsen, Geir; Sakshaug, Egil; Syvertsen, Erik. (2009) Ice algae. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • von Quillfeldt, Cecilie; Hegseth, Else Nøst; Johnsen, Geir; Sakshaug, Egil; Syvertsen, Erik E.. (2009) Ice algae. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Sakshaug, Egil; Johnsen, Geir; Kristiansen, Svein; von Quillfeldt, Cecilie; Rey, Francisco; Slagstad, Dag. (2009) Phytoplankton and primary production. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Sakshaug, Egil; Johnsen, Geir; Volent, Z.. (2009) Light. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Volent, Zsolt; Sakshaug, Egil; Sigernes, Fred; Pettersson, Lasse H.. (2009) Remote sensing in the Barents Sea. Tapir Akademisk Forlag
    Academic chapter/article/Conference paper
  • Sakshaug, Egil; Johnsen, Geir. (2005) Absorption, fluorescence excitation and photoacclimation in phytoplankton. Multi-Science Publishing
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Samset, O.; Sakshaug, Egil. (1998) Bio-optical classification of potential harmful chlorophyll c -containing prymnesiophyte blooms in Scandinavian water.
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Volent, Z.; Tangen, K.; Sakshaug, Egil. (1997) Time series of harmful and benign phytoplankton blooms in northwest European waters using the Seawatch buoy system.
    Academic chapter/article/Conference paper
  • Johnsen, Geir; Volent, Z.; Tangen, K.; Sakshaug, Egil. (1997) Time series of harmful and benign phytoplankton blooms in northwest European waters using the Seawatch buoy system.
    Academic chapter/article/Conference paper

Report

  • Nøland, Annecken; Johnsen, Geir; Aberle-Malzahn, Nicole. (2022) Autonomous Underwater Vehicle (AUV) based study of zooplankton communities, using a silhouette camera and artificial intelligence. NTNU
    Masters thesis
  • Johnsen, Geir; Aberle-Malzahn, Nicole; Fragoso, Glaucia; Thu, Maren. (2022) Phytoplankton Spring Bloom Mapping in Coastal Areas Using Autonomous Underwater Vehicle (AUV) and Optical Approaches. NTNU
    Masters thesis
  • Nevstad, Malin Bø; Johnsen, Geir; Bakken, Torkild; Larsen, Martin Kvisvik; Mogstad, Aksel Alstad. (2022) Use of different imaging systems for ROV-based mapping of complex benthic habitats. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Marnor, Camilla Mult; Johnsen, Geir; Bakken, Torkild; Mogstad, Aksel Alstad. (2022) Mapping distribution patterns of brittle stars using ROV-based imaging. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Bjerkvoll, Mikkel; Johnsen, Geir; Bakken, Torkild; Mogstad, Aksel Alstad. (2022) Aerial and underwater hyperspectral imagery for shallow benthic nature type mapping. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Søreng, Marte Opsahl; Johnsen, Geir; Bakken, Torkild; Mogstad, Aksel Alstad; Gryte, Kristoffer. (2022) Mapping of Zostera Habitat in the Sublittoral Zone using Underwater Hyperspectral Imaging and Unmanned Surface Vehicle. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Ringvold, Halldis; Johnsen, Geir; Andersen, Tom. (2021) Studies on Echinodermata from the NE Atlantic Ocean - Spatial distribution and abundance of Asteroidea, including taxonomic and molecular studies on Crossaster and Henricia genera - Value-chain results, including test fishery, biology, market and nutritional analysis on Parastichopus tremulus (Holothuroidea) from the Norwegian coast. Doktoravhandlinger ved NTNU (2021-254)
    Doctoral dissertation
  • Mogstad, Aksel Alstad; Johnsen, Geir; Sørensen, Asgeir Johan; Ludvigsen, Martin. (2021) Underwater hyperspectral imaging as a tool for benthic habitat mapping. Doktoravhandlinger ved NTNU (2021/271)
    Doctoral dissertation
  • Graham, Lisa Kristine Hernandez; Johnsen, Geir; Christensen-Dalsgaard, Signe. (2019) A pilot study assessing drones for mapping and monitoring of European shags. Institutt for biologi, NTNU
    Masters thesis
  • Fjærtoft, Kaja Lønne; Bakken, Torkild; Johnsen, Geir; Ludvigsen, Martin. (2018) Macroalgal detritus: Physical variables and impacts on the benthic macrofaunal community. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Ødegård, Øyvind; Sørensen, Asgeir Johan; Johnsen, Geir; Ludvigsen, Martin; Hansen, Roy Edgar; Maarleveld, Thijs. (2018) Towards Autonomous Operations and Systems in Marine Archaeology. Doktoravhandlinger ved NTNU (IMT-12)
    Doctoral dissertation
  • Strømsholm, Jørgen; Johnsen, Geir; Ludvigsen, Martin. (2018) Eyes beneath the surface - using a miniROV to reveal habitat and dietary choices of the European shag. NTNU MSc thesis
    Masters thesis
  • Kauko, Hanna Maria; Johnsen, Geir; Assmy, Phillipp. (2018) Light response and acclimation of macroalgae in a changing Arctic. Doktoravhandlinger ved NTNU (2018)
    Doctoral dissertation
  • Nornes, Stein Melvær; Sørensen, Asgeir Johan; Ludvigsen, Martin; Johnsen, Geir; Schjølberg, Ingrid; Ånonsen, Kjetil Bergh. (2018) Guidance and Control of Marine Robotics for Ocean Mapping and Monitoring. Doktoravhandlinger ved NTNU (2018:202)
    Doctoral dissertation
  • Mynors, Julie; Johnsen, Geir; Wernand, Marcel; Volent, Zsolt. (2017) Ocean Colour and Phytoplankton Dynamics - An examination of the Forel-Ule scale in a modern context. NTNU Trondheim
    Masters thesis
  • Kamilla, Sporsheim; Sporsheim, Kamilla; Johnsen, Geir; Reitan, Kjell Inge; Evertsen, Antii Jussi. (2017) Astaxanthin as a biomarker for fish feed loading in the marine ecosystem. NTNU, Trondheim
    Masters thesis
  • Kjeken, John; Johnsen, Geir; Ludvigsen, Martin; Thorsnes, Terje; Lågstad, Petter Arthur. (2017) The growth of benthic organisms in a dumping ground for military bombs and munitions. NTNU, Trondheim
    Masters thesis
  • Johnsen, Geir; Sandbu, Marthe; Assmy, Philipp. (2017) High Arctic Sea-Ice Algae: The Use of Rapid Light Curves to Assess Photosynthetic Performance of Different Ice-Algal Communities. Master science NTNU
    Masters thesis
  • Andersson, Ingvild Henriette Kristin; Johnsen, Geir; Bakken, Torkild; Ludvigsen, Martin. (2017) Bio-optical diversity on cold water coral habitats. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Alvsvåg, Dora Marie; Johnsen, Geir; Bakken, Torkild; Ludvigsen, Martin; Berge, Jørgen. (2017) Mapping of a seagrass habitat in Hopavågen, Sør-Trøndelag, with the use of an Autonomous Surface Vehicle combined with optical techniques. Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Paulsen, Emil; Bakken, Torkild; Ramirez-Llodra, Eva; Johnsen, Geir. (2017) Community structure and biodiversity of the benthic megafauna at the inactive hydrothermal site Mohn's Treasure, on the Mohn's Ridge, Arctic Mid-Ocean Ridge (AMOR) . Norges teknisk-naturvitenskapelige universitet Norges teknisk-naturvitenskapelige universitet
    Masters thesis
  • Jakobsen, June; Johnsen, Geir; Bakken, Torkild; Ludvigsen, Martin; Karlsen, Svein. (2016) The Tautra Cold-Water Coral Reef - Mapping and describing the biodiversity of a cold-water coral reef ecosystem in the Trondheimsfjord by use of multi-beam echo sounding and video mounted on a remotely operated vehicle. NTNU
    Masters thesis
  • Håpnes, Sverre Julian; Johnsen, Geir; Ludvigsen, Martin; Lågstad, Petter Arthur. (2016) Mapping of demersal fish and benthos by AUV equipped with optical and acoustic imagers at 600 m depth in Trondheimsfjorden. NTNU MSc
    Masters thesis
  • Liefmann, Stephanie; Johnsen, Geir; Järnegren, Johanna. (2016) Eco-physiological responses of cold-water corals to anthropogenic sedimentation and particle shape. NTNU Mastergrad
    Masters thesis
  • Lund, Le