Geir Johnsen
About
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
2024
-
Ingulstad, Mats;
Bakken, Torkild;
Ellefmo, Steinar Løve;
Johnsen, Geir;
Hagspiel, Verena.
(2024)
Villedende om hypotetiske havbunnsmineraler?.
Dagens næringsliv
Reader opinion piece
-
Ingulstad, Mats;
Bakken, Torkild;
Ellefmo, Steinar Løve;
Johnsen, Geir;
Hagspiel, Verena.
(2024)
Norge mangler kunnskap om gruvedrift i dyphavet.
Gemini (English edition)
Feature article
-
Førde, Hedda;
Grant, Stephen Denis;
Viljanen, Martta;
Majaneva, Sanna Kristiina;
Johnsen, Geir.
(2024)
Glow and Know – Evaluating the Potential of Spectral Bioluminescence as a Tool for Zooplankton Identification in situ.
NTNU
Masters thesis
-
Viljanen, Martta;
Førde, Hedda;
Majaneva, Sanna Kristiina;
Grant, Stephen Denis;
Johnsen, Geir.
(2024)
Zooplankton spectral bioluminescence database.
Database
-
Five, Taran;
Majaneva, Sanna Kristiina;
Viljanen, Martta;
Grant, Stephen Denis;
Johnsen, Geir.
(2024)
Studying Behavioral Responses to Bioluminescence in Zooplankton.
NTNU
Masters thesis
-
Ingulstad, Mats;
Bakken, Torkild;
Ellefmo, Steinar Løve;
Hagspiel, Verena;
Johnsen, Geir.
(2024)
Feil på feil om gruvedrift på havbunnen -
Stortingsmeldingen om gruvedrift på havbunnen holder ikke vann.
Dagens næringsliv
Feature article
-
Ingulstad, Mats;
Bakken, Torkild;
Johnsen, Geir;
Ellefmo, Steinar Løve;
Hagspiel, Verena.
(2024)
Norway needs to know much more before actually mining the deep sea.
Norwegian SciTech News
Feature article
-
Mo-Bjørkelund, Tore;
Majaneva, Sanna Kristiina;
Moreira Fragoso, Glaucia;
Johnsen, Geir;
Ludvigsen, Martin.
(2024)
Multi-vehicle adaptive 3D mapping for targeted ocean sampling.
PLOS ONE
Academic article
-
Liu, Hongbo;
Summers, Natalie Maria;
Chen, Yi-Chun;
Løvås, Håvard Snefjellå;
Johnsen, Geir;
Koestner, Daniel Warren.
(2024)
Pixelwise immersion factor calibration for underwater hyperspectral imaging instruments.
Optics Express
Academic article
-
Faltynkova, Andrea;
Deschênes, Catherine E.;
Zolich, Artur;
Wagner, Martin;
Johansen, Tor Arne;
Johnsen, Geir.
(2024)
Use of an uncrewed surface vehicle and near infrared hyperspectral imaging for sampling and analysis of aquatic microplastics.
Marine Pollution Bulletin
Academic article
-
Overrein, Martin Molberg;
Tinn, Phil;
Aldridge, David;
Johnsen, Geir;
Moreira Fragoso, Glaucia.
(2024)
Biomass estimations of cultivated kelp using underwater RGB images from a mini-ROV and computer vision approaches.
Frontiers in Marine Science
Academic article
-
Schartmüller, Bernhard;
Mckee, David;
Berge, Jørgen;
Johnsen, Geir.
(2024)
Calibration verification of an underwater hyperspectral imaging push broom instrument to measure light in absolute units and field demonstration.
Applied Optics
Academic article
-
Moreira Fragoso, Glaucia;
Dallolio, Alberto;
Grant, Stephen Denis;
Garrett, Joseph Landon;
Ellingsen, Ingrid Helene;
Johnsen, Geir.
(2024)
The Role of Rapid Changes in Weather on Phytoplankton Spring Bloom Dynamics From Mid-Norway Using Multiple Observational Platforms.
Journal of Geophysical Research (JGR): Oceans
Academic article
-
Moreira Fragoso, Glaucia;
Dallolio, Alberto;
Grant, Stephen Denis;
Garrett, Joseph Landon;
Ellingsen, Ingrid Helene;
Johnsen, Geir.
(2024)
The Role of Rapid Changes in Weather on Phytoplankton Spring Bloom Dynamics Captured by an Autonomous Uncrewed Surface Vehicle.
Earth and Space Science
Academic article
2023
-
Bakken, Sivert;
Luis, Kelly;
Johnsen, Geir;
Johansen, Tor Arne.
(2023)
Evaluating hyperspectral Secchi depth retrieval through hybrid modeling and regression.
Workshop on Hyperspectral Image and Signal Processing, Evolution in Remote Sensing
Academic article
-
Sørensen, Asgeir Johan;
Ludvigsen, Martin;
Sivertsen, Eirik Selnæs;
Johnsen, Geir;
Johansen, Tor Arne.
(2023)
Hvem skal samle inn, forvalte og ha tilgang til informasjon om havområdene? .
Gemini.no
Feature article
-
Sørensen, Asgeir Johan;
Ludvigsen, Martin;
Sivertsen, Eirik;
Johnsen, Geir;
Johansen, Tor Arne.
(2023)
Hvem skal samle inn, forvalte og ha tilgang til informasjon om havområdene? .
Forskning.no
Feature article
-
Deschenes, C;
Zolich, Artur;
Wagner, Martin;
Johnsen, Geir;
Johansen, Tor Arne;
Faltynkova, Andrea.
(2023)
Unmanned vehicle and hyperspectral imager for a more rapid microplastics sampling and analysis.
OCEANS
Academic article
-
Oftedahl, Live;
Sørensen, Asgeir Johan;
Johnsen, Geir.
(2023)
NTNUs first research satellite on the first mission in the Arctic.
Website (informational material)
-
Nordahl, A;
Dugstad, L;
Magnussen, O;
Bakken, JB;
Johnsen, Geir.
(2023)
Laksegriseriet.
Dagens næringsliv
Interview Journal
-
Carson, Siri Granum;
Jenssen, Munro, Bjoern;
Johnsen, Geir;
Mason, Arthur.
(2023)
En bærekraftig fremtid for Svalbard
– er utvinning av dyphavsmineraler
en del av svaret?.
Svalbardposten
Feature article
-
Anderson, Philip;
Berge, Jørgen;
Granskog, Mats A.;
Divine, Dmitry V;
Katlein, Christian;
Itkin, Polona.
(2023)
Upwelling and downwelling visible radiation measurements of the autonomous ice-tethered OptiCAL 'ee' buoy deployed during MOSAiC in the Sea Ice Ridge Observatory area.
Other product
-
Svendsen, Thea;
Majaneva, Sanna Kristiina;
Majaneva, Markus;
Båtnes, Anna Solvang;
Johnsen, Geir.
(2023)
The usability of eDNA to identify and quantify zooplankton communities.
NTNU
Masters thesis
-
Krohn-Pettersen, Gitte;
Majaneva, Sanna Kristiina;
Viljanen, Martta;
Grant, Stephen Denis;
Johnsen, Geir.
(2023)
Blinks in the dark - Detecting and characterizing flash kinetics of bioluminescence for in situ species recognition of zooplankton.
NTNU
Masters thesis
-
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
-
Sørensen, Asgeir Johan;
Ludvigsen, Martin;
Sivertsen, Eirik Selnæs;
Johnsen, Geir;
Johansen, Tor Arne.
(2023)
Hvem skal samle inn, forvalte og ha tilgang til informasjon om havområdene? .
Teknisk Ukeblad
Feature article
-
Sørensen, Asgeir Johan;
Ludvigsen, Martin;
Siversten, Eirik;
Johnsen, Geir;
Johansen, Tor Arne.
(2023)
Who should collect, manage and have access to data from the oceans?.
sciencenorway.no
Feature article
-
oudijk, AE;
Johansen, Tor Arne;
Johnsen, Geir;
Alver, Morten Omholt.
(2023)
Simulating Hyperspectral Datacubes for Ocean Color: A Foundation for Phytoplankton Recognition in Spectral Signatures.
OCEANS
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
-
Anderson, Philip;
Berge, Jørgen;
Granskog, Mats A.;
Divine, Dmitry V;
Katlein, Christian;
Itkin, Polona.
(2023)
Upwelling and downwelling visible radiation measurements of the autonomous ice-tethered OptiCAL 'gg' buoy deployed during MOSAiC in the Monster Bay area.
Other product
-
Anderson, Philip;
Berge, Jørgen;
Granskog, Mats A.;
Divine, Dmitry V;
Katlein, Christian;
Itkin, Polona.
(2023)
Upwelling and downwelling visible radiation measurements of the autonomous ice-tethered OptiCAL 'hh' buoy deployed during MOSAiC in the Dark site Second Year Ice. .
Other product
-
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
-
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
-
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
-
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
2022
-
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
-
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
-
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
-
Oftedahl, Live;
Ødegård, Øyvind;
Sørensen, Asgeir Johan;
Johnsen, Geir.
(2022)
Oppdrag Mjøsa får internasjonal oppmerksomhet.
Website (informational material)
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
2021
-
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
-
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
-
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
-
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
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Bazilchuk, Nancy Reney;
Stahl, Annette;
Johnsen, Geir;
Saad, Aya;
Thu, Maren;
Nøland, Annecken.
(2021)
Sporhunden som lukter mikroalger. .
Gemini.no
Popular scientific article
-
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
-
Bazilchuk, Nancy Reney;
Berge, Jørgen;
Johnsen, Geir.
(2021)
Lysforurensning I Arktis kan ha ødelagt forskningsresultater.
Gemini.no
Popular scientific article
-
Cardwell, CR;
Berge, Jørgen;
Johnsen, Geir.
(2021)
Arctic voyage shines light on some cold, hard truths.
The Herald, UK
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
-
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
-
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
-
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
-
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
-
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)
Pictures from an all-sky camera with hourly resolution from the light observatory at Ny-Ålesund, Svalbard, Norway (complete year 2020).
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 2018).
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
-
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
-
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 (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
-
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
-
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
-
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
-
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)
USSIMO spectroradiometer raw data time series (2017) 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 (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)
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)
USSIMO spectroradiometer raw data time series (2020) measured under the dome of a light observatory in the Arctic (Ny-Ålesund, Svalbard, Norway).
Other product
2020
-
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
-
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
-
Berge, Jørgen;
Johnsen, Geir.
(2020)
• Polar Night Exhibitions in Russia 2020.
Kaliningrad – World Ocean Museum.
Museum exhibition
-
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
-
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;
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;
Cohen, Jonathan H..
(2020)
Introduction.
Springer
Introduction
-
Johnsen, Geir;
Leu, Eva;
Gradinger, Rolf.
(2020)
Marine Micro- and Macroalgae in the Polar Night.
Springer
Academic chapter/article/Conference paper
-
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
-
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
-
Berge, Jørgen;
Johnsen, Geir.
(2020)
Life and Light at the Dead of 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
-
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
-
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
2019
-
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
-
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
-
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
-
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
-
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
-
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
2018
-
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
-
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
-
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
-
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;
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
-
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
-
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
-
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
-
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
-
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
-
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
-
Berge, Jørgen;
Johnsen, Geir.
(2018)
Lysforurensning - enda en kilde til bekymring.
Svalbardposten
Feature 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
-
Gabrielsen, Tove M.;
Johnsen, Geir.
(2018)
Skogen på Svalbard.
Svalbardposten
Popular scientific 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
-
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
-
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
2017
-
Berge, Jørgen;
Johnsen, Geir.
(2017)
Kunnskapshull om livet i Arktis i mørketiden.
Aftenposten Viten
Feature article
-
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
-
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
-
Berge, Jørgen;
Johnsen, Geir.
(2017)
Superkommunisten.
Svalbardposten
Feature article
-
Berge, Jørgen;
Johnsen, Geir.
(2017)
Om bambus, spøkelseskreps og et Arktis i endring.
Svalbardposten
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
2016
-
Johnsen, Geir.
(2016)
Yrende liv i Isfjorden.
Svalbardposten
Popular scientific article
-
Bjørgan, Espen Halvorsen;
Johnsen, Geir;
Kjeken, Jon;
Ludvigsen, Martin.
(2016)
Fant buss på 600 m dybde.
Adresseavisen
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
-
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
-
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
-
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;
Ødegård, Øyvind.
(2016)
Mark spiser opp vrak på havbunnen.
Fiskaren
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
-
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
-
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
-
Berge, Jørgen;
Ødegård, Øyvind;
Johnsen, Geir.
(2016)
Opp fra polarnattens mørke.
Aftenposten Viten
Feature article
-
Gätzschmann, Per;
Hårsaker, Karstein;
Johnsen, Geir;
Leite, Stein Roar;
Pedersen, Solbjørg;
Sørumgård, Marit.
(2016)
Nye oppdagelser i polarnatta - video.
Polarnatt
Museum exhibition
-
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
-
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
-
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
-
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
-
Bondø, Tor-Hartvig;
Johnsen, Geir;
Berge, Jørgen.
(2016)
Fant yrende liv i polarnatta.
VG : Verdens gang
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;
Sørensen, Asgeir Johan;
Ødegård, Øyvind.
(2016)
Dark lords, werewolves and Indiana Jones in the polar night.
Gemini (English edition)
Interview Journal
-
Berge, Jørgen;
Johnsen, Geir;
Ødegård, Øyvind.
(2016)
Kinderegg i polarnatten.
Svalbardposten
Feature article
-
Krüger, Frida Jørstad;
Johnsen, Geir;
Kjeken, John;
Ludvigsen, Martin.
(2016)
Gammel buss ble korallrev.
NRK Viten
Popular scientific article
-
Liefmann, Stephanie;
Johnsen, Geir;
Järnegren, Johanna.
(2016)
Eco-physiological responses of cold-water corals to anthropogenic sedimentation and particle shape.
NTNU Mastergrad
Masters thesis
-
Berge, Jørgen;
Renaud, Paul E.;
Johnsen, Geir;
Darnis, Gerald;
Geoffroy, Maxime;
Daase, Malin.
(2016)
I grenselandet (mellom Tull og Thule).
Svalbardposten
Popular scientific article
-
Berge, Jørgen;
Ødegård, Øyvind;
Johnsen, Geir.
(2016)
A bitter-sweet symphony.
Svalbardposten
Feature article
-
Berge, Jørgen;
Johnsen, Geir;
Ludvigsen, Martin;
Cohen, Jonathan.
(2016)
Design for latskap - men med store muligheter.
Svalbardposten
Feature 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
-
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
2015
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
Berge, Jørgen;
Johnsen, Geir;
Aarekol, Lena.
(2015)
Life and light in the dead of night.
Museumsutstilling
Museum exhibition
2014
-
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
-
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
-
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
-
Hatlebakk, Maja;
Johnsen, Geir;
Søreide, Janne.
(2014)
Effect of lipids and fatty acid composition on success of reproduction in Calanus glacialis.
NTNU
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
-
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
-
Førde, Henny;
Reitan, Kjell Inge;
Johnsen, Geir.
(2014)
Development of bryozoan fouling on cultivated kelp (Saccharina latissima) in Norway.
NTNU
Masters thesis
-
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
-
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
-
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
-
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
-
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
-
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
-
Kvernvik, Ane Cecilie;
Johnsen, Geir;
Aamot, Inga.
(2014)
How lamina age influence photosynthetic response to light variations in Saccharina latissima.
NTNU
Masters thesis
-
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
-
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
-
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;
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
-
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
-
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
-
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
-
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
-
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
2013
-
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
-
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
-
Berge, Jørgen;
Johnsen, Geir;
Falk-Pettersen, Stig.
(2013)
Mørkets hemmeligheter.
Svalbardposten
Popular scientific 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
-
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
-
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
2012
-
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
-
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
-
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
-
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
-
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
-
Belseth, Elen;
Johnsen, Geir;
Berge, Jørgen.
(2012)
Eco-physiology of the Arctic kelp Laminaria solidungula.
NTNU Master thesis
Masters thesis
-
Gabrielsen, Tove M;
Quillfeldt, Cecilie von;
Johnsen, Geir;
Berge, Jørgen.
(2012)
Varm vinter, sen vår i fjorden.
Svalbardposten
Reader opinion piece
-
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
2011
-
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
-
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
-
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
-
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
-
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
-
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)
Preface.
Cambridge University Press
Foreword
-
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
-
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
2010
-
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
-
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
-
Johnsen, Geir;
Søreide, Fredrik.
(2010)
Underwater hyperspectral imaging of marine mineral deposits.
Underwater Mining meeting Institute (UMI)
Abstract
2009
-
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
-
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
-
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
-
Sakshaug, Egil;
Johnsen, Geir;
Kovacs, Kit.
(2009)
Ecosystem Barents Sea.
Tapir Akademisk Forlag
Tapir Akademisk Forlag
Academic anthology/Conference proceedings
-
Øye, Ane-Marte;
Johnsen, Geir.
(2009)
Photobioreactor time-series of a simulated bloom of Emiliania huxleyi.
NTNU, Institutt for biologi
Masters thesis
-
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
-
Thoen, Hanne Halkinrud;
Johnsen, Geir.
(2009)
Pigmentation in the Arctic deep-sea amphipods Eurythenes gryllus and Anonyx sp.
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
-
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
-
Quillfeldt, C.v.;
Hegseth, E.N.;
Johnsen, Geir;
Sakshaug, E.;
Syvertsen, E.E..
(2009)
Ice algae.
Tapir Akademisk Forlag
Academic chapter/article/Conference paper
-
Sakshaug, E.;
Johnsen, Geir;
Volent, Z.
(2009)
Light.
Tapir Akademisk Forlag
Academic chapter/article/Conference paper
-
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, 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
-
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;
Volent, Z..
(2009)
Light.
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
-
Sakshaug, Egil;
Johnsen, Geir;
Kovacs, Kit M..
(2009)
Ecosystem Barents Sea.
Tapir Akademisk Forlag
Tapir Akademisk Forlag
Non-fiction book
-
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
2008
-
Hovland, Erlend Kjeldsberg;
Johnsen, Geir;
Moline, Mark.
(2008)
Combined use of AUV and hyperspectral imaging to mapping sea-surface and macroalgae.
Ocean Optics
Abstract
-
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
-
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
-
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
-
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
2007
-
Johnsen, Geir;
Volent, Zsolt;
Sigernes, F..
(2007)
Fine scale studies using hyper-spectral remote sensing.
ESSAS Meeting in Marine Arctic Climate
Report
-
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
-
Volent, Z;
Johnsen, Geir;
Sigernes, Fred.
(2007)
Kelp forest mapping by use of airborne hyperspectral imager.
Journal of Applied Remote Sensing
Academic 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
-
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
-
Ludvigsen, Martin;
Sortland, Bjørn;
Johnsen, Geir;
Singh, Hanumant.
(2007)
Applications of Geo-Referenced Underwater Photo Mosaics in Marine Biology and Archaeology.
Oceanography
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;
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
-
Johnsen, Geir.
(2007)
Arctic Life: Bridging ecosystem function using remote sensing technologies.
Svalbard Science Forum
Popular scientific article
-
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
-
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
-
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
-
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
-
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
-
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
-
Kleiven, Mona;
Johnsen, Geir.
(2007)
Pigmentation in Halocynthia pyriformis from Isfjorden, Spitsbergen.
NTNU, Institutt for biologi
Masters thesis
-
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
2006
-
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
-
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
-
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
-
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;
Gulliksen, Bjørn;
Slagstad, Dag;
Pampanin, Daniella.
(2006)
The Mytilus edulis population in Svalbard: how and why.
Marine Ecology Progress Series
Academic article
2005
-
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
-
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
-
Bordvik, Hans Otto;
Johnsen, Geir.
(2005)
“Forskning og foto under vann”.
NEWTON websider (NRK)
Popular scientific 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
-
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
-
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
2004
-
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
-
Hancke, Torunn Beate;
Johnsen, Geir.
(2004)
SISCAL processor evaluation document.
www.siscal.net
Report
2003
-
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
-
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
-
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
-
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
2002
-
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
-
Johansen, Torunn Beate;
Johnsen, Geir.
(2002)
End User requirement evaluation document.
[Mangler utgivernavn]
Report
-
Johansen, Torunn Beate;
Johnsen, Geir.
(2002)
End User Requirements document.
[Mangler utgivernavn]
Report
2001
-
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;
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
-
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;
Johansson, Niclas;
Johnsen, Geir;
Børsheim, Knut Yngve;
Graneli, Edna.
(2001)
Phagotrophy and toxicity in the photosynthetic Prymnesium patelliferum (Haptophyte).
Limnology and Oceanography
Academic article
-
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
1998
-
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
-
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
1997
-
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
-
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
-
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
1996
-
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
-
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;
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 cf. pouchetii blooms.
Marine Ecology Progress Series
Academic article
-
Johnsen, Geir;
Sakshaug, Egil.
(1996)
Light harvesting in bloom-forming marine phytoplankton: Species-specifity and photoacclimation,.
Scientia Marina
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
1995
-
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;
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
1994
-
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
-
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
-
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
-
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.
(1994)
Light Harvesting and Utiliation in Marine Phytoplankton: Species-Specific and Photoadaptive Responses. Dr. Scient.
Thesis in Marine Botany, University of Trondheim
Doctoral dissertation
1993
-
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;
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
1992
-
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;
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
-
Johnsen, Geir;
Sakshaug, Egil;
Vernet, Maria.
(1992)
Pigment composition, spectral characteriation and photosynthetic parameters in Chrysochromulina polylepis.
Marine Ecology Progress Series
Academic article
-
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
1991
-
Johnsen, Geir.
(1991)
Proceedings from a scientific working meeting.
Fisken og Havet
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
-
Johnsen, Geir;
Hegseth, Else Nøst.
(1991)
Photoadaptation of sea-ice microalgae in the Barents Sea.
Polar Biology
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
-
Ingulstad, Mats;
Bakken, Torkild;
Ellefmo, Steinar Løve;
Johnsen, Geir;
Hagspiel, Verena.
(2024)
Villedende om hypotetiske havbunnsmineraler?.
Dagens næringsliv
Reader opinion piece
-
Ingulstad, Mats;
Bakken, Torkild;
Ellefmo, Steinar Løve;
Johnsen, Geir;
Hagspiel, Verena.
(2024)
Norge mangler kunnskap om gruvedrift i dyphavet.
Gemini (English edition)
Feature article
-
Ingulstad, Mats;
Bakken, Torkild;
Ellefmo, Steinar Løve;
Hagspiel, Verena;
Johnsen, Geir.
(2024)
Feil på feil om gruvedrift på havbunnen -
Stortingsmeldingen om gruvedrift på havbunnen holder ikke vann.
Dagens næringsliv
Feature article
-
Ingulstad, Mats;
Bakken, Torkild;
Johnsen, Geir;
Ellefmo, Steinar Løve;
Hagspiel, Verena.
(2024)
Norway needs to know much more before actually mining the deep sea.
Norwegian SciTech News
Feature article
-
Mo-Bjørkelund, Tore;
Majaneva, Sanna Kristiina;
Moreira Fragoso, Glaucia;
Johnsen, Geir;
Ludvigsen, Martin.
(2024)
Multi-vehicle adaptive 3D mapping for targeted ocean sampling.
PLOS ONE
Academic article
-
Liu, Hongbo;
Summers, Natalie Maria;
Chen, Yi-Chun;
Løvås, Håvard Snefjellå;
Johnsen, Geir;
Koestner, Daniel Warren.
(2024)
Pixelwise immersion factor calibration for underwater hyperspectral imaging instruments.
Optics Express
Academic article
-
Faltynkova, Andrea;
Deschênes, Catherine E.;
Zolich, Artur;
Wagner, Martin;
Johansen, Tor Arne;
Johnsen, Geir.
(2024)
Use of an uncrewed surface vehicle and near infrared hyperspectral imaging for sampling and analysis of aquatic microplastics.
Marine Pollution Bulletin
Academic article
-
Overrein, Martin Molberg;
Tinn, Phil;
Aldridge, David;
Johnsen, Geir;
Moreira Fragoso, Glaucia.
(2024)
Biomass estimations of cultivated kelp using underwater RGB images from a mini-ROV and computer vision approaches.
Frontiers in Marine Science
Academic article
-
Schartmüller, Bernhard;
Mckee, David;
Berge, Jørgen;
Johnsen, Geir.
(2024)
Calibration verification of an underwater hyperspectral imaging push broom instrument to measure light in absolute units and field demonstration.
Applied Optics
Academic article
-
Moreira Fragoso, Glaucia;
Dallolio, Alberto;
Grant, Stephen Denis;
Garrett, Joseph Landon;
Ellingsen, Ingrid Helene;
Johnsen, Geir.
(2024)
The Role of Rapid Changes in Weather on Phytoplankton Spring Bloom Dynamics From Mid-Norway Using Multiple Observational Platforms.
Journal of Geophysical Research (JGR): Oceans
Academic article
-
Moreira Fragoso, Glaucia;
Dallolio, Alberto;
Grant, Stephen Denis;
Garrett, Joseph Landon;
Ellingsen, Ingrid Helene;
Johnsen, Geir.
(2024)
The Role of Rapid Changes in Weather on Phytoplankton Spring Bloom Dynamics Captured by an Autonomous Uncrewed Surface Vehicle.
Earth and Space Science
Academic article
-
Bakken, Sivert;
Luis, Kelly;
Johnsen, Geir;
Johansen, Tor Arne.
(2023)
Evaluating hyperspectral Secchi depth retrieval through hybrid modeling and regression.
Workshop on Hyperspectral Image and Signal Processing, Evolution in Remote Sensing
Academic article
-
Sørensen, Asgeir Johan;
Ludvigsen, Martin;
Sivertsen, Eirik Selnæs;
Johnsen, Geir;
Johansen, Tor Arne.
(2023)
Hvem skal samle inn, forvalte og ha tilgang til informasjon om havområdene? .
Gemini.no
Feature article
-
Sørensen, Asgeir Johan;
Ludvigsen, Martin;
Sivertsen, Eirik;
Johnsen, Geir;
Johansen, Tor Arne.
(2023)
Hvem skal samle inn, forvalte og ha tilgang til informasjon om havområdene? .
Forskning.no
Feature article
-
Deschenes, C;
Zolich, Artur;
Wagner, Martin;
Johnsen, Geir;
Johansen, Tor Arne;
Faltynkova, Andrea.
(2023)
Unmanned vehicle and hyperspectral imager for a more rapid microplastics sampling and analysis.
OCEANS
Academic article
-
Nordahl, A;
Dugstad, L;
Magnussen, O;
Bakken, JB;
Johnsen, Geir.
(2023)
Laksegriseriet.
Dagens næringsliv
Interview Journal
-
Carson, Siri Granum;
Jenssen, Munro, Bjoern;
Johnsen, Geir;
Mason, Arthur.
(2023)
En bærekraftig fremtid for Svalbard
– er utvinning av dyphavsmineraler
en del av svaret?.
Svalbardposten
Feature 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
-
Sørensen, Asgeir Johan;
Ludvigsen, Martin;
Sivertsen, Eirik Selnæs;
Johnsen, Geir;
Johansen, Tor Arne.
(2023)
Hvem skal samle inn, forvalte og ha tilgang til informasjon om havområdene? .
Teknisk Ukeblad
Feature article
-
Sørensen, Asgeir Johan;
Ludvigsen, Martin;
Siversten, Eirik;
Johnsen, Geir;
Johansen, Tor Arne.
(2023)
Who should collect, manage and have access to data from the oceans?.
sciencenorway.no
Feature article
-
oudijk, AE;
Johansen, Tor Arne;
Johnsen, Geir;
Alver, Morten Omholt.
(2023)
Simulating Hyperspectral Datacubes for Ocean Color: A Foundation for Phytoplankton Recognition in Spectral Signatures.
OCEANS
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
-
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
-
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
-
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;
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
-
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
-
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
-
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
-
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
-
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
-
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
-
Bazilchuk, Nancy Reney;
Stahl, Annette;
Johnsen, Geir;
Saad, Aya;
Thu, Maren;
Nøland, Annecken.
(2021)
Sporhunden som lukter mikroalger. .
Gemini.no
Popular scientific article
-
Bazilchuk, Nancy Reney;
Berge, Jørgen;
Johnsen, Geir.
(2021)
Lysforurensning I Arktis kan ha ødelagt forskningsresultater.
Gemini.no
Popular scientific article
-
Cardwell, CR;
Berge, Jørgen;
Johnsen, Geir.
(2021)
Arctic voyage shines light on some cold, hard truths.
The Herald, UK
Popular scientific 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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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;
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
-
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
-
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
-
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
-
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
-
Berge, Jørgen;
Johnsen, Geir.
(2018)
Lysforurensning - enda en kilde til bekymring.
Svalbardposten
Feature 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
-
Gabrielsen, Tove M.;
Johnsen, Geir.
(2018)
Skogen på Svalbard.
Svalbardposten
Popular scientific article
-
Berge, Jørgen;
Johnsen, Geir.
(2017)
Kunnskapshull om livet i Arktis i mørketiden.
Aftenposten Viten
Feature article
-
Berge, Jørgen;
Johnsen, Geir.
(2017)
Superkommunisten.
Svalbardposten
Feature article
-
Berge, Jørgen;
Johnsen, Geir.
(2017)
Om bambus, spøkelseskreps og et Arktis i endring.
Svalbardposten
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
-
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
-
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
-
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
-
Johnsen, Geir.
(2016)
Yrende liv i Isfjorden.
Svalbardposten
Popular scientific article
-
Bjørgan, Espen Halvorsen;
Johnsen, Geir;
Kjeken, Jon;
Ludvigsen, Martin.
(2016)
Fant buss på 600 m dybde.
Adresseavisen
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
-
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
-
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
-
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;
Ødegård, Øyvind.
(2016)
Mark spiser opp vrak på havbunnen.
Fiskaren
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
-
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
-
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
-
Berge, Jørgen;
Ødegård, Øyvind;
Johnsen, Geir.
(2016)
Opp fra polarnattens mørke.
Aftenposten Viten
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
-
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
-
Bondø, Tor-Hartvig;
Johnsen, Geir;
Berge, Jørgen.
(2016)
Fant yrende liv i polarnatta.
VG : Verdens gang
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;
Sørensen, Asgeir Johan;
Ødegård, Øyvind.
(2016)
Dark lords, werewolves and Indiana Jones in the polar night.
Gemini (English edition)
Interview Journal
-
Berge, Jørgen;
Johnsen, Geir;
Ødegård, Øyvind.
(2016)
Kinderegg i polarnatten.
Svalbardposten
Feature article
-
Krüger, Frida Jørstad;
Johnsen, Geir;
Kjeken, John;
Ludvigsen, Martin.
(2016)
Gammel buss ble korallrev.
NRK Viten
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
-
Berge, Jørgen;
Ødegård, Øyvind;
Johnsen, Geir.
(2016)
A bitter-sweet symphony.
Svalbardposten
Feature article
-
Berge, Jørgen;
Johnsen, Geir;
Ludvigsen, Martin;
Cohen, Jonathan.
(2016)
Design for latskap - men med store muligheter.
Svalbardposten
Feature 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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
Berge, Jørgen;
Johnsen, Geir;
Falk-Pettersen, Stig.
(2013)
Mørkets hemmeligheter.
Svalbardposten
Popular scientific 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
-
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
-
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
-
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
-
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
-
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
-
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
-
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
-
Johnsen, Geir;
Søreide, Fredrik.
(2010)
Underwater hyperspectral imaging of marine mineral deposits.
Underwater Mining meeting Institute (UMI)
Abstract
-
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
-
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
-
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
-
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
-
Hovland, Erlend Kjeldsberg;
Johnsen, Geir;
Moline, Mark.
(2008)
Combined use of AUV and hyperspectral imaging to mapping sea-surface and macroalgae.
Ocean Optics
Abstract
-
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
-
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
-
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
-
Volent, Z;
Johnsen, Geir;
Sigernes, Fred.
(2007)
Kelp forest mapping by use of airborne hyperspectral imager.
Journal of Applied Remote Sensing
Academic 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
-
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
-
Ludvigsen, Martin;
Sortland, Bjørn;
Johnsen, Geir;
Singh, Hanumant.
(2007)
Applications of Geo-Referenced Underwater Photo Mosaics in Marine Biology and Archaeology.
Oceanography
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;
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
-
Johnsen, Geir.
(2007)
Arctic Life: Bridging ecosystem function using remote sensing technologies.
Svalbard Science Forum
Popular scientific 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
-
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
-
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;
Pampanin, Daniella.
(2006)
The Mytilus edulis population in Svalbard: how and why.
Marine Ecology Progress Series
Academic 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
-
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
-
Bordvik, Hans Otto;
Johnsen, Geir.
(2005)
“Forskning og foto under vann”.
NEWTON websider (NRK)
Popular scientific 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
-
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
-
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 End User Requirement evaluation document.
www.siscal.net. Satellite-based Information System on Coastal Areas and Lakes. IST 2000
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
-
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
-
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
-
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
-
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;
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
-
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;
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
-
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
-
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;
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
-
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;
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 cf. pouchetii blooms.
Marine Ecology Progress Series
Academic article
-
Johnsen, Geir;
Sakshaug, Egil.
(1996)
Light harvesting in bloom-forming marine phytoplankton: Species-specifity and photoacclimation,.
Scientia Marina
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
-
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;
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.
(1994)
Photoadaptation of Prorocentrum minimum and Heterocapsa pygmaea (Dinoflagellates): Chromoprotein changes and the consequenses for spectral absorption.
EOS
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
-
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
-
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
-
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;
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.
(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;
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
-
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.
(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
-
Johnsen, Geir;
Hegseth, Else Nøst.
(1991)
Photoadaptation of sea-ice microalgae in the Barents Sea.
Polar Biology
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.
(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;
Kovacs, Kit M..
(2009)
Ecosystem Barents Sea.
Tapir Akademisk Forlag
Tapir Akademisk Forlag
Non-fiction book
-
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;