Hossein Nahavandchi

About

Hossein Nahavandchi is a professor of geodesy. His research interest is Earth monitoring/climate change using satellite (Gravimetry/Altimetry/GPS) data.

Biography: Hossein Nahavandchi holds a PhD degree (1998) from Royal Institute of Technology in Stockholm. His primary research interest is satellite Gravimetry, Altimetry and GPS. He has been lecturing in the Geomatics and Geodesy fields since 1990. Hossein’s career includes being a member of staff at Isfahan University (as Senior Lecturer and Head of Department), Royal Institute of Technology in Stockholm (as Research Associate), Tehran University (as Assistant Professor), and Norwegian University of Science and Technology (as Associate Professor and Professor). He also worked for Iranian National Mapping Authority and National Cartographic Center (NCC) in several functions. He has been Vice-Dean, Dean, and the Rector of the College of Engineering, Division Director, Chair of the Borad and Board member of Research and Planning Division, and Education Department in Iran. His research projects and other activities in Civil Engineering have attracted more than 120 million NOK to the university sector since 1991. They have also resulted in a strong international network. Over 155 publications and presentations are the results of his research projects.

My Research/Teaching Interests:

Current Research: Monitoring Ocean Microplastics using GPS Signals

We use spaceborne observations from a novel remote sensing technique. The technique utilizes reflected signals of Global Navigation Satellite Systems (GNSS) and is called GNSS-Reflectometry (GNSS-R). The project aims to provide a regularly updated worldwide map of microplastics distribution on the ocean surface. The observations used in the analysis are collected using bistatic sensors onboard the NASA CYGNSS mission over the equatorial and part of the mid-latitudes regions. More than four years of GNSS-R observations are used so far. An overall verification of the results is performed using three available global microplastics models. The overall microplastic concentration map produced from GNSS-R observations shows a noticeably good agreement with the models. The promising results suggest that the GNSS-R technique can be an effective geodetic tool for the constant monitoring of microplastics on the ocean surface.

Current Research: GNSS Remote Sensing of the Arctic and Ocean using Spaceborne Reflectometry (Joint project of NTNU with GFZ)

Remote sensing using the signals of Global Navigation Satellite System (GNSS) is an established method providing a new source of observations for the study of the Earth and its atmosphere. GNSS Reflectometry (GNSS-R), a novel Earth observation technique, exploits the reflected GNSS signals from the land or water bodies to retrieve information about different geophysical parameters. This technique, in ground-based, air- or spaceborne configuration, has been widely used and still is being pursued for a variety of applications over land, ocean and ice. Different processing approaches could be used or developed to retrieve unprecedented high spatiotemporal resolution scatterometric or altimetric measurements from the reflectometry observations.

Several GNSS-R sensors onboard small satellite missions have already demonstrated the feasibility and competence of this technique. Although NASA CYGNSS (CYclone GNSS) mission currently provides GNSS-R data stream over tropical regions, the higher latitude regions as well as Polar waters are yet to be covered.

The joint project of Norwegian university of science and technology (NTNU) with GFZ will investigate the theory and design of an Earth remote sensing sensor onboard small satellites capable of measuring the oceanographic parameters related to altimetry in Norwegian and Polar waters. The project exploits GNSS-R (Global Navigation Satellite System - Reflectometry) concept which allows to use a relatively cost-efficient low-power passive sensor in a compact payload onboard future NTNU SmallSats.

The project provides required information about the methodology and instrumentation of an observing system with different geophysical parameters of interest such as sea ice thickness, sea surface height and wave height. The outcome will be implemented in the NTNU SmallSats and will be used operationally in an integrated maritime/Arctic observation network. It is foreseen to use in-situ measurements acquired by autonomous unmanned vehicle systems for calibration and enhancement of the GNSS-R products. The ultimate goal is to integrate the designed GNSS-R sensor in an integrated observation network to provide a high spatiotemporal resolution monitoring of the arctic and oceans, as the key components of the Earth’s climate system.

Left: Integrated Arctic and ocean observation network consisting of foreseen GNSS-R sensor onboard a SmallSat assisted and validated by low-altitude unmanned aerial vehicles (UAVs) and unmanned surface vehicles (USVs) for high resolution sea surface height and wave height measurements, and autonomous underwater vehicles (AUVs) for under-ice thickness measurements. Right: CYGNSS NBRCS (σ0) over two mid-latitude mesoscale ocean eddies near the south coast of Japan at two different times; in 3 dimensions in the local defined coordinate system. The evolution of the σ0 can be explained by the anomalies of sea surface temperature. The warm core of the top eddy produces higher wind speed (lower σ0) while the colder edges, by contrast, cause lower wind speeds (higher σ0).

Current Research: Assessing Groundwater depletion and dynamics using GRACE and hydrological data

Groundwater is a strategic reservoir and its shortage will cause the next global crisis. Water resource issues are often very complex and frequently require large amounts of diverse data. Collection of data by traditional means (e.g. fieldwork) can be quite difficult at times, especially in remote areas, as well as costly and resource intensive. The Gravity Recovery and Climate Experiment (GRACE) satellite gravity data can be very useful providing a cost-effective means of replacing or complimenting field data collection. GRACE satellites measure monthly changes in total terrestrial water storage by converting observed gravity anomalies into changes of equivalent water height. We use this methodology to process GRACE satellite-to-satellite tracking data to estimate groundwater depletion in the Middle East and a developed methodology to use GRACE data with enhanced spatial scale over Iran’s water basins. We remove leakage-in mass signals of the Caspian Sea and adding back the ocean model contribution that had apparently introduced a spurious positive trend over the Black Sea. To isolate the groundwater contributions, we develop a local hydrological model including soil moisture, snow, canopy, and river storage and subtract it from the GRACE total water storage results.

Groundwater changes in six different Iran's water basins using GRACE data between 2003 and 2013

Recently completed research: Quantifying land subsidence and groundwater exploitation using InSAR time series and in-situ measurements

Land subsidence due to the overdrafting of groundwater resources for industrial and agricultural purposes is a geological hazard that affects many urban and agricultural areas in the world. Several environmental effects and consequences are associated with land subsidence including damage to infrastructures and buildings, increased risk of flooding in coastal areas and accelerated erosion along Earth fissures and drainage systems. Monitoring the spatial extent and temporal evolution of surface deformation associated with fluid withdrawal is critical to mitigate hazards associated with this phenomenon. Among ground and space-based geodetic methods used for measuring land subsidence, space-borne InSAR enables a unique imaging capability for the assessment of subsidence in response to fluid extraction from subsurface reservoirs. Using SAR data from the ENVISAT, ALOS and Sentinel-1 satellites, we analyzed nearly a decade of land subsidence in the Rafsanjan region in Iran. An InSAR time-series analysis showed a persistent pattern of subsidence, with peak values found west of the city of Rafsanjan.

Average velocity maps derived from (a) ENVISAT descending, (b) ENVISAT ascending, (c) ALOS, (d) Sentinel-1 ascending, and (e) Sentinel-1 descending. The observation periods corresponding to the velocity maps are shown in (f).

We have also worked on large-scale national high-quality SAR monitoring of Norway. As an example, an interferogram over Norway has been shown in Figure below. We are working with ionospheric and tropospheric corrections.

An interfeogram over Norway using Sentinel-1 data

Standard methodology of the SAR and InSAR technique in displacement mapping has been improved. We implemented a polarimetric optimization approach on Sentinel-1 dual-polarization (VV–VH) images to improve the standard persistent scatterer interferometric synthetic aperture radar (PS-InSAR) method. Combining persistent scatterers (PS) and distributed scatterers (DS) is important for effective displacement monitoring using time-series of SAR data. However, for large stacks of SAR data, the DS analysis using existing standard algorithms becomes a time-consuming process. SqueeSAR is an approach for extracting signals from DS. We optimized this technique and evaluated the performance of our approach on 50 Sentinel-1 images acquired over Trondheim in Norway. We have made the SqueeSAR selection algorithm 98% more efficient and more robust in the case of few images. We implemented our approach in the StaMPS/MTI processing chain to deliver a time-series of combined PS and DS more efficiently than the existing StaMPS/MTI combined algorithm.

Surface displacement velocity over Trondheim with standard and optimized methods

Current Research: Quantifying water vapor contents by homogenization of GNSS time series

Quantifying water vapor, a major greenhouse gas of the atmosphere, is necessary for the climate and meteorological applications. Global Navigation Satellite System (GNSS) signals are promising measuring tools for monitoring water vapor content, but the use of GNSS products for estimating climatic trend requires homogeneity assessment in order to increase reliability and accuracy of the results. We have developed a data homogenization method based on singular spectrum analysis as a subspace-based technique. The ERA-Interim simulated data has been selected as the reference dataset. After homogenization, we used Principle Component Analysis (PCA) method to extract climate signals. We employed our developed technique over 214 permanent GNSS stations over Germany between 2010 and 2016 (7 years).

Left: A component of homogenized GNSS-derived dataset reflecting the overall classification of the climate in Germany. Right:  The climatic divisions based on Köppen Climate Classification system.

Recently completed research: Ocean wave measurments using single GPS Buoy

Accurate forecasts of wave conditions are of the utmost important to all who live, work, or travel on or near ocean. To improve the wave prediction models, field measurement of ocean wave parameters is necessary. Those parameters are wave height, period and direction. We applied a methodology to derive ocean wave parameters (wave height, wave period and direction) from GPS data. The power spectrums of GPS data (among its errors) and buoy movement (excited by ocean wave) were the basis for the estimation of wave parameters. Because of the buoy movement data is in the band frequency of GPS data which signal to noise ratio (SNR) is very low, the most important point in design of high pass filter is the cut-off frequency selection of the filter. The figure below shows the power spectrum of the GPS height data in m2/Hz.

Recently completed research: Greenland Ice-mass balance from satellite gravity observations

The Gravity Recovery and Climate Experiment (GRACE) satellite mission provides temporal variations of Earth gravity field with a period of around one month. GRACE measures changes in Earth's gravity field caused by regional shifts in the Earth's mass, including ice sheets, oceans and Water stored in the soil and in underground aquifers. We used GRACE data to estimate the rate of ice mass variability over Greenland. The Figure below shows monthly ice mass changes summed over the entire Greenland ice sheet, between April 2002 and February 2010, estimated in Gigatonne grom three GRACE data sets released by GFZ (Potsdam), JPL(California) and CSR (Texas). Note that this plot shows deviation from the average ice mass over the 2002 to 2010 period. It does not mean that the ice sheet was gaining ice before 2006 but that ice mass was over the 2002 to 2010 average. The ice mass was below the 2002 to 2010 average after 2006. The trend of the best fitting straight line for CSR data is -163±20 Gigatonne per year. The results also indicate the the ice-mass loss rate has been increasing in the time period between 2002 and 2010.

Recently completed research: Ocean circulation in North Atlantic and the Arctic sea from satellite altimetry observations

The Ocean plays a key role in determining the global climate. To develop techniques for pridicting furure climate, one must undrestand the dynamics of the global ocean circulation. A viable approach to observing the global and regional ocean circulations with sufficient resolution is the use of a satellite radar altimeter to measure the Mean Sea Surface (MSS) height. Multiple radar altimetry data from ESA satellites of ENVISAT, ERS-1 and ERS-2 and NASA satellite of GFO were used to determine the NTNU MSS model. NTNU MSS model is used to derive the mean dynamic topography and the ocesn circulation as it is shown in the Figure below. This plot shows the surface currents system in the North Atlantic and the Arctic sea for the time period 1993-2007. Flow of warm water is shown as red arrow and cold water as blue arrow. The Northward flow of warm water in the North Atlantic is partly balanced by southward flow of clod water in the East Greenland. Note that the detalied surface currents are not shown in this picture.

Research Intrests

Satellite Positioning GPS
Satellite Gravimetry and Altimetry
Climate Change Studies
Polar Research
Ocean Circulation and Transport

Teaching

TBA4852 Interdisciplinary Teamwork
TBA4565 Geomatics, Specialization Course
TBA4560 Geomatics, Specialization Project
TBA4231 Applied geomatics
TBA4236 Theoretical geomatics
TBA4245 Geodesy
TBA4251 Programming in geomatics
TTT4234 Space Technology I
TBA4925 Geomatics, Master Thesis
BA8200 Advanced Theory of Errors and Adjustment
BA8202 Advanced Physical Geodesy
BA8604 Satellite Gravimetry and Altimetry
BA8605 Advanced Global Positioning System (GPS)
BA8203 An integrated Earth System Approach to the Study of Ocean Climate

Research Projects

Arctic and Antarctic Mass balance (Ice loss) from satellite gravity and satellite altimetry measurements
Ocean Circulation and Transport Between the North Atlantic and Arctic sea (OCTAS)
New improvments in Geoidal height modeling
Development of a regional GPS-based model of Ionospheric for Norway
Arctic geoid for ocean circulation, sea-ice exploration and climate change

Links:

Publications

2022

Hoseini, Mostafa; Nahavandchi, Hossein. (2022) The potential of spaceborne GNSS reflectometry for detecting ocean surface currents. Remote Sensing of Environment. volum 282.
Academic article
Safdari, Zohreh; Joodaki, Gholamreza; Nahavandchi, Hossein. (2022) A Technical Note on Least Squares Mascon Fitting to GRACE Satellite Data to Estimate Total Water Storage Changes in the Middle East. Satellite Monitoring of Water Resources in the Middle East.
Academic chapter/article/Conference paper
Safdari, Zohreh; Nahavandchi, Hossein; Joodaki, Gholamreza. (2022) Estimation of Groundwater Depletion in Iran’s Catchments Using Well Data. Water. volum 14 (1).
Academic article

2021

Asgarimehr, Milad; Hoseini, Mostafa; Semmling, Maximilian; Ramatschi, Markus; Camps, Adriano; Nahavandchi, Hossein; Haas, Rüdiger; Wickert, Jens. (2021) Remote Sensing of Precipitation Using Reflected GNSS Signals: Response Analysis of Polarimetric Observations. IEEE Transactions on Geoscience and Remote Sensing. volum 60.
Academic article
Hoseini, Mostafa; Semmling, Maximilian; Nahavandchi, Hossein; Rennspiess, Erik; Ramatschi, Markus; Haas, Rüdiger; Strandberg, Joakim; Wickert, Jens. (2021) On the Response of Polarimetric GNSS-Reflectometry to Sea Surface Roughness. IEEE Transactions on Geoscience and Remote Sensing. volum 59 (9).
Academic article
Rajabi, Mahmoud; Hoseini, Mostafa; Nahavandchi, Hossein; Semmling, Maximilian; Ramaschi, Markus; Goli, Mehdi; Hass, R ̈udiger; Wickert, Jens. (2021) A Performance Assessment of Polarimetric GNSS-R Sea Level Monitoring in the Presence of Sea Surface Roughness. IEEE International Geoscience and Remote Sensing Symposium proceedings.
Academic article
Rajabi, Mahmoud; Hoseini, Mostafa; Nahavandchi, Hossein; Semmling, Maximillian; Ramatschi, Markus; Goli, Mehdi; Haas, Rudiger; Wickert, Jens. (2021) Polarimetric GNSS-R Sea Level Monitoring using I/Q Interference Patterns at Different Antenna Configurations and Carrier Frequencies. IEEE Transactions on Geoscience and Remote Sensing. volum 60.
Academic article

2020

Hoseini, Mostafa; Alshawaf, Fadwa; Nahavandchi, Hossein; Dick, Galina; Wickert, Jens. (2020) Towards a zero-difference approach for homogenizing GNSS tropospheric products. GPS Solutions. volum 24 (8).
Academic article
Hoseini, Mostafa; Asgarimehr, Milad; Zavorotny, valery; Nahavandchi, Hossein; Ruf, chris; Wickert, Jens. (2020) First Evidence of Mesoscale Ocean Eddies Signature in GNSS Reflectometry Measurements. Remote Sensing. volum 12 (542).
Academic article
Rajabi, Mahmoud; Amiri-Simkooei, Alireza; Nahavandchi, Hossein; Nafisi, Vahab. (2020) Modeling and Prediction of Regular Ionospheric Variations and Deterministic Anomalies. Remote Sensing. volum 12 (6).
Academic article
Rajabi, Mahmoud; Nahavandchi, Hossein; Hoseini, Mostafa. (2020) Evaluation of CYGNSS Observations for Flood Detection and Mapping during Sistan and Baluchestan Torrential Rain in 2020. Water. volum 12 (7).
Academic article
Shamshiri, Roghayeh; Motagh, Mahdi; Nahavandchi, Hossein; Haghshenas, Mahmud; Hoseini, Mostafa. (2020) Improving tropospheric corrections on large-scale Sentinel-1 interferogramsusing a machine learning approach for integration with GNSS-derived zenithtotal delay (ZTD). Remote Sensing of Environment. volum 239 (111608).
Academic article

2019

Hoseini, Mostafa; Asgarimehr, Milad; Nahavandchi, Hossein; Wickert, Jens. (2019) Spaceborne GNSS-R Observations of Mesoscale Ocean Eddies; Preliminary Results from Cygnss Mission. IEEE International Geoscience and Remote Sensing Symposium proceedings.
Academic article

2018

Shamshiri, Roghayeh; Nahavandchi, Hossein; Motagh, Mahdi. (2018) Persistent Scatterer Analysis Using Dual-Polarization Sentinel-1 Data: Contribution From VH Channel. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing. volum 11 (9).
Academic article
Shamshiri, Roghayeh; Nahavandchi, Hossein; Motagh, Mahdi; Andy, Hooper. (2018) Efficient Ground Surface Displacement Monitoring Using Sentinel-1 Data: Integrating Distributed Scatterers (DS) Identified Using Two-Sample t-Test with Persistent Scatterers (PS). Remote Sensing. volum 10 (5).
Academic article

2017

Motagh, Mahdi; Shamshiri, Roghayeh; Haghshenas, Mahmud; Wetzel, Hans-Ulrich; Akbari, Bahman; Nahavandchi, Hossein; Roessner, Sigrid; Arabi, Siavash. (2017) Quantifying groundwater exploitation induced subsidence in the Rafsanjan plain, southeastern Iran, using InSAR time-series and in situ measurements. Engineering Geology. volum 218.
Academic article
Nahavandchi, Hossein; Haakonsen, Trond Arve; Aas, Håvard. (2017) Accuracy investigation of UAV Photomapping. Kart og Plan. volum 77 (3).
Academic article
Shamshiri, Roghayeh; Nahavandchi, Hossein; Joodaki, Gholamreza. (2017) Seasonal variation analysis of Greenland ice mass time-series. Acta Geodaetica et Geophysica Hungarica. volum 53 (1).
Academic article

2016

Shamshiri, Roghayeh; Nahavandchi, Hossein; Motagh, Mahdi. (2016) Deformation analysis of the Trondheim city from SAR Interferometry. Proceedings Living Planet Symposium 2016.
Academic chapter/article/Conference paper
Shamshiri, Roghayeh; Nahavandchi, Hossein; Motagh, Mahdi. (2016) Deformation analysis of the Trondheim city from SAR Interferometry. ESA SP.
Academic article
Shamshiri, Roghayeh; Nahavandchi, Hossein; Motagh, Mahdi; Haghshenas, Mahmud. (2016) Multi-sensor InSAR analysis of surface displacement over coastal urban city of Trondheim. Procedia Computer Science. volum 100.
Academic article

2015

Nahavandchi, Hossein; Joodaki, Gholamreza; Schwartz, Vegar. (2015) GRACE-derived ice-mass loss spread over Greenland. Journal of Geodetic Science. volum 5 (1).
Academic article
Nahavandchi, Hossein; Skogseth, Terje. (2015) Klimaovervåking med satellitter. Byggeindustrien.
Article

2013

Joodaki, Gholamreza; Nahavandchi, Hossein; Cheng, Kevin. (2013) Ocean Wave Measurement Using GPS Buoys. Journal of Geodetic Science. volum 3 (3).
Academic article
Joodaki, Gholamreza; Nahavandchi, Hossein; Ghazavi, Kourosh. (2013) Steric sea level changes from ENVISAT and GRACE in the Nordic Seas. ESA SP.
Academic article
Nahavandchi, Hossein; Skjeset, Lars. (2013) Geoid-type surface determination using a gravimetric quasigeoid model and GNSS/leveling data- A case study in eastern Norway. Kart og Plan. volum 73.
Academic article

2012

Joodaki, Gholamreza; Nahavandchi, Hossein. (2012) Mass balance and mass loss acceleration of the Greenland ice sheet (2002 – 2011) from GRACE gravity data. Journal of Geodetic Science. volum 2 (2).
Academic article
Joodaki, Gholamreza; Nahavandchi, Hossein. (2012) Mass loss of the Greenland ice sheet from GRACE time-variable gravity measurements. Studia Geophysica et Geodaetica. volum 56 (1).
Academic article
Nahavandchi, Hossein; Joodaki, Gholamreza. (2012) Greenland ice-melt spread into Northwest Coast revealed by GRACE (GRACE data viser at issmeltingen på Grønland sprer seg til nordvestkysten). Kart og Plan. volum 72 (3).
Academic article
Nahavandchi, Hossein; Mahdavipour, Hossein. (2012) Sammenligning av geoidens høyde utledet fra geopotensialmodellen EGM2008 med GPS/nivellementsdata i et testområde i Iran (Comparison of geoid heights from the EGM2008 geopotential model and GPS/levelling data in a study area in Iran). Kart og Plan. volum 72 (1).
Academic article

2011

Ghazavi, Kourosh; Nahavandchi, Hossein. (2011) Mean Sea Surface and ocean circulation in North Atlantic and the Arctic Sea. Journal of Geodetic Science. volum 1 (2).
Academic article

2010

Joodaki, Gholamreza; Nahavandchi, Hossein. (2010) Greenland mass balance estimation from satellite gravity measurements. ESA SP.
Academic article
Nahavandchi, Hossein; Joodaki, Gholamreza. (2010) CORRELATION ANALYSIS OF MULTIPATH EFFECTS IN GPS-CODE AND CARRIER PHASE OBSERVATIONS. Survey Review. volum 42 (316).
Academic article

2008

Nahavandchi, Hossein; Soltanpour, Ali. (2008) Local ionospheric modelling of GPS code and carrier phase observations. Survey Review. volum 40 (309).
Academic article
Omang, Ove Christian Dahl; Hunegnaw, Addisu; Solheim, Dag; Lysaker, Dagny; Ghazavi, Kourosh; Nahavandchi, Hossein. (2008) Updated OCTAS geoid in the northern North Atlantic - OCTAS07. International Association of Geodesy Symposia. volum 133 (2).
Academic article

2007

Ghazavi, Kourosh; Nahavandchi, Hossein; Omang, Ove Christian Dahl; Solheim, Dag; Soltanpour, Ali; Shum, C.K.; Yi, Yochan; Lysaker, Dagny; Pettersen, Bjørn Ragnvald; Drange, Helge; Johannessen, Johnny; Gidskehaug, Arne. (2007) The OCTAS06-North Atlantic/Arctic ocean mean sea surface model. Geophysical Research Abstracts. volum 9.
Abstract
Ghazavi, Kourosh; Nahavandchi, Hossein; Omang, Ove Christian Dahl; Solheim, Dag; Soltanpour, Ali; Shum, C.K.; Yi, Yochan; Lysaker, Dagny; Pettersen, Bjørn Ragnvald; Drange, Helge; Johannessen, Johnny; Gidskehaug, Arne. (2007) OCTAS with a focus on the importance of a high precision mean sea surface. Geophysical Research Abstracts. volum 9.
Abstract
Solheim, Dag; Omang, Ove Christian Dahl; Hunegnaw, Addisu; Drange, Helge; Johannessen, Johnny; siegismund, Frank; Nahavandchi, Hossein; Ghazavi, Kourosh; Pettersen, Bjørn Ragnvald; Lysaker, Dagny; Gidskehaug, Arne; Plag, Hans-Peter. (2007) The OCTAS poject, The geoid, the mean sea surface and the mean dynamic topography. Proceedings of the 3rd International GOCE User Workshop.
Academic chapter/article/Conference paper
Solheim, Dag; Omang, Ove Christian Dahl; Hunegnaw, Addisu; Soltanpour, Ali; Drange, Helge; Johannessen, Johnny; Siegismund, Frank; Nahavandchi, Hossein; Ghazavi, Kourosh; Pettersen, Bjørn Ragnvald; Lysaker, Dagny; Gidskehaug, Arne; Plag, Hans-Peter. (2007) The OCTAS project, the interrelationship between the geoid, the mean sea surface and the mean dynamic topography. Geophysical Research Abstracts. volum 9.
Abstract
Soltanpour, Ali; Solheim, Dag; Omang, Ove Christian Dahl; Nahavandchi, Hossein; Ghazavi, Kourosh; Pettersen, Bjørn Ragnvald; Lysaker, Dagny; Drange, Helge; Johannessen, Johnny; Gidskehaug, Arne; Plag, Hans-Peter. (2007) Assessment and Validation of the geoid, MSS and MDT models in the OCTAS project. Geophysical Research Abstracts. volum 9.
Abstract
Ghazavi, Kourosh; Nahavandchi, Hossein; Omang, Ove Christian Dahl; Solheim, Dag; Soltanpour, Ali; Shum, C.K.; Yi, Yochan; Lysaker, Dagny; Pettersen, Bjørn Ragnvald; Drange, Helge; Johannessen, Johnny; Gidskehaug, Arne. (2007) The OCTAS07- North Atlantic/Arctic ocean mean sea surface model based on a wavelet adjustment of multiple satellite altimetry data. Geophysical Research Abstracts. volum 9.
Abstract
Nahavandchi, Hossein; Soltanpour, Ali. (2007) Different Gravimetric Geoid Models over Iran with and without Terrestrial Gravity Data. General Command of Mapping.
Academic article
Omang, Ove Christian Dahl; Solheim, Dag; Hunegnaw, Addisu; Lysaker, Dagny Iren; Ghazavi, K; Nahavandchi, Hossein. (2007) OCTAS with a focus on the importance of a high accuracy geoid. Gravity Field of the Earth, Proceedings of the 1st International Symposium of the International Gravity Field Service.
Academic chapter/article/Conference paper
Omang, Ove Christian Dahl; Solheim, Dag; Hunegnaw, Addisu; Lysaker, Dagny; Ghazavi, Kourosh; Nahavandchi, Hossein. (2007) Ocean Circulation and Transport Between North Atlantic and the Arctic Sea with a focus on the importance of a high accuracy geoid model. General Command of Mapping.
Academic article
Omang, Ove Christian Dahl; Solheim, Dag; Hunegnaw, Addisu; Lysaker, Dagny; Ghazavi, Kourosh; Nahavandchi, Hossein. (2007) Updated OCTAS geoid – OCTAS07. Geophysical Research Abstracts. volum 9.
Abstract
Soltanpour, Ali; Nahavandchi, Hossein; Ghazavi, Kourosh. (2007) Recovery of marine gravity anomalies from ERS1, ERS2 and ENVISAT satellite altimetry data for geoid computations over Norway. Studia Geophysica et Geodaetica. volum 51 (3).
Academic article

2006

Nahavandchi, Hossein. (2006) HIGH-RESOLUTION GEOID DETERMINATION- IRanian Gravimetric Geoid 2005 (IRGG05). 2006.
Report
Nahavandchi, Hossein; Soltanpour, Ali. (2006) Improved determination of heights using a conversion surface by combining gravimetric quasi-geoid/geoid and GPS-levelling height differences. Studia Geophysica et Geodaetica. volum 50 (2).
Academic article
Soltanpour, Ali; Nahavandchi, Hossein. (2006) A new high-resolution geoid for Iran with emphasise on different modification procedures and new GRACE geopotential model. Geophysical Research Abstracts. volum 8.
Abstract
Soltanpour, Ali; Nahavandchi, Hossein; Featherstone, Will. (2006) Geoid-type surface determination using wavelet-based combination of gravimetric quasi/geoid and GPS-levelling data. Geophysical Research Abstracts. volum 8.
Abstract
Soltanpour, Ali; Nahavandchi, Hossein; Featherstone, Will. (2006) The Use of Second-generation Wavelets to Combine a Gravimetric Quasigeoid Model with GPS-levelling Data. Journal of Geodesy. volum 80 (2).
Academic article
Soltanpour, Ali; Nahavandchi, Hossein; Ghazavi, Kourosh. (2006) Recovery of marine gravity anomaly from ERS2 and ENVISAT data and its contribution to the geoid of Norway. Geophysical Research Abstracts. volum 8.
Abstract

2005

Nyrnes, Erik; Torkildsen, Torgeir; Nahavandchi, Hossein. (2005) Detection of Gross Errors in Wellbore Directional Surveying for Petroleum Production with emphasis on Reliability Analyses. Kart og Plan. volum 65 (2).
Academic article

2004

Nahavandchi, Hossein. (2004) The Quest for a Precise Geoidal Height Model. Kart og Plan. volum 64 (1).
Academic article
Nahavandchi, Hossein. (2004) The direct effect and downward continuation correction of atmospheric masses in gravimetric geoid determination. Bollettino di Geodesia e Scienze Affini. volum 63 (1).
Academic article
Nahavandchi, Hossein; Soltanpour, Ali; Nyrnes, Erik. (2004) A New Gravimetric Geoidal Height Model over Norway Computed by the Least-Squares Modification Parameters. Gravity, Geoid, and Space Missions.
Other
Nahavandchi, Hossein. (2004) A new strategy for the atmospheric gravity effect in gravimetric geoid determination. Journal of Geodesy. volum 77.
Academic article

2003

Nahavandchi, Hossein. (2003) A Comparison of the classical and recent formulae of handling the effects of close and distant topographic masses in gravimetric geoid computations. Newton's Bulletin.
Academic article
Nahavandchi, Hossein. (2003) Corrections to "Two different methods of geoidal height determinations using a spherical harmonic representation of the geopotential, topographic corrections and the height anomaly-geoidal height difference". Journal of Geodesy. volum 76 (11-12).
Errata
Nahavandchi, Hossein. (2003) Use of global geopotential models for comparison of gravimetric geoid estimators by the modification of Stoke's formula. Bollettino di Geodesia e Scienze Affini. volum 62 (2).
Academic article

2002

Nahavandchi, Hossein. (2002) Two different methods of geoidal height determinations using a spherical harmonic representation of the geopotential, topographic corrections and the height anomaly-geoidal height difference. Journal of Geodesy. volum 76 (6-7).
Academic article

2001

Nahavandchi, Hossein. (2001) Physical Geodesy. 2001.
Compendium
Nahavandchi, Hossein; Sjöberg, Lars Erik. (2001) Precise geoid determination over Sweden using the Stokes-Helmert method and improved topographic corrections. Journal of Geodesy. volum 75 (2-3).
Academic article
Nahavandchi, Hossein; Sjöberg, Lars Erik. (2001) Precise geoid determination over Sweden using the Stokes-Helmert method and improved topographic corrections. Journal of Geodesy. volum 75 (2/3).
Academic article
Nahavandchi, Hossein; Sjöberg, Lars Erik. (2001) Two different views of topographical and downward-continuation corrections in the Stokes-Helmert approach to geoid computation. Journal of Geodesy. volum 74 (11-12).
Academic article
Nahavandchi, Hossein; Sjöberg, Lars Erik. (2001) Two different views of topographical and downward-continuation corrections in the Stokes-Helmert approach to geoid computation. Journal of Geodesy. volum 74 (11/12).
Academic article

2000

Nahavandchi, Hossein. (2000) Computation of mean free-air gravity anomalies by Bjerhammar's deterministic and collocation methods over Scandinavia. Survey Review. volum 35 (278).
Academic article
Nahavandchi, Hossein. (2000) The direct topographical correction in gravimetric geoid determination by the Stokes-Helmert method. Journal of Geodesy. volum 74 (6).
Academic article
Sjöberg, Lars Erik; Nahavandchi, Hossein. (2000) The atmospheric geoid effects in Stokes’ formula. Geophysical Journal International. volum 140 (1).
Academic article

1999

Nahavandchi, Hossein. (1999) Geoid terrain correction to power H (super 5) of satellite derived geopotential models. Bollettino di Geodesia e Scienze Affini. volum 58 (3).
Academic article
Nahavandchi, Hossein. (1999) Terrain correction computations by spherical harmonics and integral formulas. Physics and chemistry of the earth. Part A: Solid earth and geodesy. volum 24 (1).
Academic article
Sjöberg, Lars Erik; Nahavandchi, Hossein. (1999) On the indirect effect in the Stokes-Helmert method of geoid determination. Journal of Geodesy. volum 73 (2).
Academic article

1998

Nahavandchi, Hossein. (1998) On some methods of downward continuation of mean free-air gravity anomaly. IGeS Bulletin. volum 8.
Academic article
Nahavandchi, Hossein. (1998) Precise Gravimetric-GPS Geoid Determination with Improved Topographic Corrections Applid over Sweden. 1998.
Doctoral dissertation
Nahavandchi, Hossein; Sjöberg, Lars Erik. (1998) Terrain corrections to power H3 in gravimetric geoid determination. Journal of Geodesy. volum 72 (3).
Academic article
Nahavandchi, Hossein; Sjöberg, Lars Erik. (1998) Unification of vertical datums by GPS and gravimetric geoid models using modified Stokes formula. Marine Geodesy. volum 21 (4).
Academic article

1997

Nahavandchi, Hossein. (1997) Connection of vertical datums using geoid models. Scientific and Technical Quarterly Journal of NCC. volum 8 (29).
Academic article
Nahavandchi, Hossein. (1997) Terrain effects in geoid determination over Iran. Scientific and Technical Quarterly Journal of NCC. volum 7 (28).
Academic article
Nahavandchi, Hossein. (1997) The Atmospheric Geoid effects over Iran. Scientific and Technical Quarterly Journal of NCC. volum 8 (29).
Academic article

1996

Nahavandchi, Hossein. (1996) Determination of Spherical Harmonics coefficients by Integral Formula and Collocation method. Scientific and Technical Quarterly Journal of NCC. volum 6 (27).
Academic article

1995

Nahavandchi, Hossein. (1995) External Gravity Potential of the Earth and the problem of spherical harmonics Convergency in Physical Geodesy. Scientific and Technical Quarterly Journal of NCC. volum 6 (23).
Academic article

1994

Nahavandchi, Hossein. (1994) Compilation of 10' by 10' mean gravity anomalies in Iran. 1994.
Master thesis

1993

Nahavandchi, Hossein. (1993) Geoid Determination with geometrical methods. Scientific and Technical Journal of NGO. volum 2 (6).
Academic article

Journal publications

Hoseini, Mostafa; Nahavandchi, Hossein. (2022) The potential of spaceborne GNSS reflectometry for detecting ocean surface currents. Remote Sensing of Environment. volum 282.
Academic article
Safdari, Zohreh; Nahavandchi, Hossein; Joodaki, Gholamreza. (2022) Estimation of Groundwater Depletion in Iran’s Catchments Using Well Data. Water. volum 14 (1).
Academic article
Asgarimehr, Milad; Hoseini, Mostafa; Semmling, Maximilian; Ramatschi, Markus; Camps, Adriano; Nahavandchi, Hossein; Haas, Rüdiger; Wickert, Jens. (2021) Remote Sensing of Precipitation Using Reflected GNSS Signals: Response Analysis of Polarimetric Observations. IEEE Transactions on Geoscience and Remote Sensing. volum 60.
Academic article
Hoseini, Mostafa; Semmling, Maximilian; Nahavandchi, Hossein; Rennspiess, Erik; Ramatschi, Markus; Haas, Rüdiger; Strandberg, Joakim; Wickert, Jens. (2021) On the Response of Polarimetric GNSS-Reflectometry to Sea Surface Roughness. IEEE Transactions on Geoscience and Remote Sensing. volum 59 (9).
Academic article
Rajabi, Mahmoud; Hoseini, Mostafa; Nahavandchi, Hossein; Semmling, Maximilian; Ramaschi, Markus; Goli, Mehdi; Hass, R ̈udiger; Wickert, Jens. (2021) A Performance Assessment of Polarimetric GNSS-R Sea Level Monitoring in the Presence of Sea Surface Roughness. IEEE International Geoscience and Remote Sensing Symposium proceedings.
Academic article
Rajabi, Mahmoud; Hoseini, Mostafa; Nahavandchi, Hossein; Semmling, Maximillian; Ramatschi, Markus; Goli, Mehdi; Haas, Rudiger; Wickert, Jens. (2021) Polarimetric GNSS-R Sea Level Monitoring using I/Q Interference Patterns at Different Antenna Configurations and Carrier Frequencies. IEEE Transactions on Geoscience and Remote Sensing. volum 60.
Academic article
Hoseini, Mostafa; Alshawaf, Fadwa; Nahavandchi, Hossein; Dick, Galina; Wickert, Jens. (2020) Towards a zero-difference approach for homogenizing GNSS tropospheric products. GPS Solutions. volum 24 (8).
Academic article
Hoseini, Mostafa; Asgarimehr, Milad; Zavorotny, valery; Nahavandchi, Hossein; Ruf, chris; Wickert, Jens. (2020) First Evidence of Mesoscale Ocean Eddies Signature in GNSS Reflectometry Measurements. Remote Sensing. volum 12 (542).
Academic article
Rajabi, Mahmoud; Amiri-Simkooei, Alireza; Nahavandchi, Hossein; Nafisi, Vahab. (2020) Modeling and Prediction of Regular Ionospheric Variations and Deterministic Anomalies. Remote Sensing. volum 12 (6).
Academic article
Rajabi, Mahmoud; Nahavandchi, Hossein; Hoseini, Mostafa. (2020) Evaluation of CYGNSS Observations for Flood Detection and Mapping during Sistan and Baluchestan Torrential Rain in 2020. Water. volum 12 (7).
Academic article
Shamshiri, Roghayeh; Motagh, Mahdi; Nahavandchi, Hossein; Haghshenas, Mahmud; Hoseini, Mostafa. (2020) Improving tropospheric corrections on large-scale Sentinel-1 interferogramsusing a machine learning approach for integration with GNSS-derived zenithtotal delay (ZTD). Remote Sensing of Environment. volum 239 (111608).
Academic article
Hoseini, Mostafa; Asgarimehr, Milad; Nahavandchi, Hossein; Wickert, Jens. (2019) Spaceborne GNSS-R Observations of Mesoscale Ocean Eddies; Preliminary Results from Cygnss Mission. IEEE International Geoscience and Remote Sensing Symposium proceedings.
Academic article
Shamshiri, Roghayeh; Nahavandchi, Hossein; Motagh, Mahdi. (2018) Persistent Scatterer Analysis Using Dual-Polarization Sentinel-1 Data: Contribution From VH Channel. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing. volum 11 (9).
Academic article
Shamshiri, Roghayeh; Nahavandchi, Hossein; Motagh, Mahdi; Andy, Hooper. (2018) Efficient Ground Surface Displacement Monitoring Using Sentinel-1 Data: Integrating Distributed Scatterers (DS) Identified Using Two-Sample t-Test with Persistent Scatterers (PS). Remote Sensing. volum 10 (5).
Academic article
Motagh, Mahdi; Shamshiri, Roghayeh; Haghshenas, Mahmud; Wetzel, Hans-Ulrich; Akbari, Bahman; Nahavandchi, Hossein; Roessner, Sigrid; Arabi, Siavash. (2017) Quantifying groundwater exploitation induced subsidence in the Rafsanjan plain, southeastern Iran, using InSAR time-series and in situ measurements. Engineering Geology. volum 218.
Academic article
Nahavandchi, Hossein; Haakonsen, Trond Arve; Aas, Håvard. (2017) Accuracy investigation of UAV Photomapping. Kart og Plan. volum 77 (3).
Academic article
Shamshiri, Roghayeh; Nahavandchi, Hossein; Joodaki, Gholamreza. (2017) Seasonal variation analysis of Greenland ice mass time-series. Acta Geodaetica et Geophysica Hungarica. volum 53 (1).
Academic article
Shamshiri, Roghayeh; Nahavandchi, Hossein; Motagh, Mahdi. (2016) Deformation analysis of the Trondheim city from SAR Interferometry. ESA SP.
Academic article
Shamshiri, Roghayeh; Nahavandchi, Hossein; Motagh, Mahdi; Haghshenas, Mahmud. (2016) Multi-sensor InSAR analysis of surface displacement over coastal urban city of Trondheim. Procedia Computer Science. volum 100.
Academic article
Nahavandchi, Hossein; Joodaki, Gholamreza; Schwartz, Vegar. (2015) GRACE-derived ice-mass loss spread over Greenland. Journal of Geodetic Science. volum 5 (1).
Academic article
Nahavandchi, Hossein; Skogseth, Terje. (2015) Klimaovervåking med satellitter. Byggeindustrien.
Article
Joodaki, Gholamreza; Nahavandchi, Hossein; Cheng, Kevin. (2013) Ocean Wave Measurement Using GPS Buoys. Journal of Geodetic Science. volum 3 (3).
Academic article
Joodaki, Gholamreza; Nahavandchi, Hossein; Ghazavi, Kourosh. (2013) Steric sea level changes from ENVISAT and GRACE in the Nordic Seas. ESA SP.
Academic article
Nahavandchi, Hossein; Skjeset, Lars. (2013) Geoid-type surface determination using a gravimetric quasigeoid model and GNSS/leveling data- A case study in eastern Norway. Kart og Plan. volum 73.
Academic article
Joodaki, Gholamreza; Nahavandchi, Hossein. (2012) Mass balance and mass loss acceleration of the Greenland ice sheet (2002 – 2011) from GRACE gravity data. Journal of Geodetic Science. volum 2 (2).
Academic article
Joodaki, Gholamreza; Nahavandchi, Hossein. (2012) Mass loss of the Greenland ice sheet from GRACE time-variable gravity measurements. Studia Geophysica et Geodaetica. volum 56 (1).
Academic article
Nahavandchi, Hossein; Joodaki, Gholamreza. (2012) Greenland ice-melt spread into Northwest Coast revealed by GRACE (GRACE data viser at issmeltingen på Grønland sprer seg til nordvestkysten). Kart og Plan. volum 72 (3).
Academic article
Nahavandchi, Hossein; Mahdavipour, Hossein. (2012) Sammenligning av geoidens høyde utledet fra geopotensialmodellen EGM2008 med GPS/nivellementsdata i et testområde i Iran (Comparison of geoid heights from the EGM2008 geopotential model and GPS/levelling data in a study area in Iran). Kart og Plan. volum 72 (1).
Academic article
Ghazavi, Kourosh; Nahavandchi, Hossein. (2011) Mean Sea Surface and ocean circulation in North Atlantic and the Arctic Sea. Journal of Geodetic Science. volum 1 (2).
Academic article
Joodaki, Gholamreza; Nahavandchi, Hossein. (2010) Greenland mass balance estimation from satellite gravity measurements. ESA SP.
Academic article
Nahavandchi, Hossein; Joodaki, Gholamreza. (2010) CORRELATION ANALYSIS OF MULTIPATH EFFECTS IN GPS-CODE AND CARRIER PHASE OBSERVATIONS. Survey Review. volum 42 (316).
Academic article
Nahavandchi, Hossein; Soltanpour, Ali. (2008) Local ionospheric modelling of GPS code and carrier phase observations. Survey Review. volum 40 (309).
Academic article
Omang, Ove Christian Dahl; Hunegnaw, Addisu; Solheim, Dag; Lysaker, Dagny; Ghazavi, Kourosh; Nahavandchi, Hossein. (2008) Updated OCTAS geoid in the northern North Atlantic - OCTAS07. International Association of Geodesy Symposia. volum 133 (2).
Academic article
Ghazavi, Kourosh; Nahavandchi, Hossein; Omang, Ove Christian Dahl; Solheim, Dag; Soltanpour, Ali; Shum, C.K.; Yi, Yochan; Lysaker, Dagny; Pettersen, Bjørn Ragnvald; Drange, Helge; Johannessen, Johnny; Gidskehaug, Arne. (2007) The OCTAS06-North Atlantic/Arctic ocean mean sea surface model. Geophysical Research Abstracts. volum 9.
Abstract
Ghazavi, Kourosh; Nahavandchi, Hossein; Omang, Ove Christian Dahl; Solheim, Dag; Soltanpour, Ali; Shum, C.K.; Yi, Yochan; Lysaker, Dagny; Pettersen, Bjørn Ragnvald; Drange, Helge; Johannessen, Johnny; Gidskehaug, Arne. (2007) OCTAS with a focus on the importance of a high precision mean sea surface. Geophysical Research Abstracts. volum 9.
Abstract
Solheim, Dag; Omang, Ove Christian Dahl; Hunegnaw, Addisu; Soltanpour, Ali; Drange, Helge; Johannessen, Johnny; Siegismund, Frank; Nahavandchi, Hossein; Ghazavi, Kourosh; Pettersen, Bjørn Ragnvald; Lysaker, Dagny; Gidskehaug, Arne; Plag, Hans-Peter. (2007) The OCTAS project, the interrelationship between the geoid, the mean sea surface and the mean dynamic topography. Geophysical Research Abstracts. volum 9.
Abstract
Soltanpour, Ali; Solheim, Dag; Omang, Ove Christian Dahl; Nahavandchi, Hossein; Ghazavi, Kourosh; Pettersen, Bjørn Ragnvald; Lysaker, Dagny; Drange, Helge; Johannessen, Johnny; Gidskehaug, Arne; Plag, Hans-Peter. (2007) Assessment and Validation of the geoid, MSS and MDT models in the OCTAS project. Geophysical Research Abstracts. volum 9.
Abstract
Ghazavi, Kourosh; Nahavandchi, Hossein; Omang, Ove Christian Dahl; Solheim, Dag; Soltanpour, Ali; Shum, C.K.; Yi, Yochan; Lysaker, Dagny; Pettersen, Bjørn Ragnvald; Drange, Helge; Johannessen, Johnny; Gidskehaug, Arne. (2007) The OCTAS07- North Atlantic/Arctic ocean mean sea surface model based on a wavelet adjustment of multiple satellite altimetry data. Geophysical Research Abstracts. volum 9.
Abstract
Nahavandchi, Hossein; Soltanpour, Ali. (2007) Different Gravimetric Geoid Models over Iran with and without Terrestrial Gravity Data. General Command of Mapping.
Academic article
Omang, Ove Christian Dahl; Solheim, Dag; Hunegnaw, Addisu; Lysaker, Dagny; Ghazavi, Kourosh; Nahavandchi, Hossein. (2007) Ocean Circulation and Transport Between North Atlantic and the Arctic Sea with a focus on the importance of a high accuracy geoid model. General Command of Mapping.
Academic article
Omang, Ove Christian Dahl; Solheim, Dag; Hunegnaw, Addisu; Lysaker, Dagny; Ghazavi, Kourosh; Nahavandchi, Hossein. (2007) Updated OCTAS geoid – OCTAS07. Geophysical Research Abstracts. volum 9.
Abstract
Soltanpour, Ali; Nahavandchi, Hossein; Ghazavi, Kourosh. (2007) Recovery of marine gravity anomalies from ERS1, ERS2 and ENVISAT satellite altimetry data for geoid computations over Norway. Studia Geophysica et Geodaetica. volum 51 (3).
Academic article
Nahavandchi, Hossein; Soltanpour, Ali. (2006) Improved determination of heights using a conversion surface by combining gravimetric quasi-geoid/geoid and GPS-levelling height differences. Studia Geophysica et Geodaetica. volum 50 (2).
Academic article
Soltanpour, Ali; Nahavandchi, Hossein. (2006) A new high-resolution geoid for Iran with emphasise on different modification procedures and new GRACE geopotential model. Geophysical Research Abstracts. volum 8.
Abstract
Soltanpour, Ali; Nahavandchi, Hossein; Featherstone, Will. (2006) Geoid-type surface determination using wavelet-based combination of gravimetric quasi/geoid and GPS-levelling data. Geophysical Research Abstracts. volum 8.
Abstract
Soltanpour, Ali; Nahavandchi, Hossein; Featherstone, Will. (2006) The Use of Second-generation Wavelets to Combine a Gravimetric Quasigeoid Model with GPS-levelling Data. Journal of Geodesy. volum 80 (2).
Academic article
Soltanpour, Ali; Nahavandchi, Hossein; Ghazavi, Kourosh. (2006) Recovery of marine gravity anomaly from ERS2 and ENVISAT data and its contribution to the geoid of Norway. Geophysical Research Abstracts. volum 8.
Abstract
Nyrnes, Erik; Torkildsen, Torgeir; Nahavandchi, Hossein. (2005) Detection of Gross Errors in Wellbore Directional Surveying for Petroleum Production with emphasis on Reliability Analyses. Kart og Plan. volum 65 (2).
Academic article
Nahavandchi, Hossein. (2004) The Quest for a Precise Geoidal Height Model. Kart og Plan. volum 64 (1).
Academic article
Nahavandchi, Hossein. (2004) The direct effect and downward continuation correction of atmospheric masses in gravimetric geoid determination. Bollettino di Geodesia e Scienze Affini. volum 63 (1).
Academic article
Nahavandchi, Hossein. (2004) A new strategy for the atmospheric gravity effect in gravimetric geoid determination. Journal of Geodesy. volum 77.
Academic article
Nahavandchi, Hossein. (2003) A Comparison of the classical and recent formulae of handling the effects of close and distant topographic masses in gravimetric geoid computations. Newton's Bulletin.
Academic article
Nahavandchi, Hossein. (2003) Corrections to "Two different methods of geoidal height determinations using a spherical harmonic representation of the geopotential, topographic corrections and the height anomaly-geoidal height difference". Journal of Geodesy. volum 76 (11-12).
Errata
Nahavandchi, Hossein. (2003) Use of global geopotential models for comparison of gravimetric geoid estimators by the modification of Stoke's formula. Bollettino di Geodesia e Scienze Affini. volum 62 (2).
Academic article
Nahavandchi, Hossein. (2002) Two different methods of geoidal height determinations using a spherical harmonic representation of the geopotential, topographic corrections and the height anomaly-geoidal height difference. Journal of Geodesy. volum 76 (6-7).
Academic article
Nahavandchi, Hossein; Sjöberg, Lars Erik. (2001) Precise geoid determination over Sweden using the Stokes-Helmert method and improved topographic corrections. Journal of Geodesy. volum 75 (2-3).
Academic article
Nahavandchi, Hossein; Sjöberg, Lars Erik. (2001) Precise geoid determination over Sweden using the Stokes-Helmert method and improved topographic corrections. Journal of Geodesy. volum 75 (2/3).
Academic article
Nahavandchi, Hossein; Sjöberg, Lars Erik. (2001) Two different views of topographical and downward-continuation corrections in the Stokes-Helmert approach to geoid computation. Journal of Geodesy. volum 74 (11-12).
Academic article
Nahavandchi, Hossein; Sjöberg, Lars Erik. (2001) Two different views of topographical and downward-continuation corrections in the Stokes-Helmert approach to geoid computation. Journal of Geodesy. volum 74 (11/12).
Academic article
Nahavandchi, Hossein. (2000) Computation of mean free-air gravity anomalies by Bjerhammar's deterministic and collocation methods over Scandinavia. Survey Review. volum 35 (278).
Academic article
Nahavandchi, Hossein. (2000) The direct topographical correction in gravimetric geoid determination by the Stokes-Helmert method. Journal of Geodesy. volum 74 (6).
Academic article
Sjöberg, Lars Erik; Nahavandchi, Hossein. (2000) The atmospheric geoid effects in Stokes’ formula. Geophysical Journal International. volum 140 (1).
Academic article
Nahavandchi, Hossein. (1999) Geoid terrain correction to power H (super 5) of satellite derived geopotential models. Bollettino di Geodesia e Scienze Affini. volum 58 (3).
Academic article
Nahavandchi, Hossein. (1999) Terrain correction computations by spherical harmonics and integral formulas. Physics and chemistry of the earth. Part A: Solid earth and geodesy. volum 24 (1).
Academic article
Sjöberg, Lars Erik; Nahavandchi, Hossein. (1999) On the indirect effect in the Stokes-Helmert method of geoid determination. Journal of Geodesy. volum 73 (2).
Academic article
Nahavandchi, Hossein. (1998) On some methods of downward continuation of mean free-air gravity anomaly. IGeS Bulletin. volum 8.
Academic article
Nahavandchi, Hossein; Sjöberg, Lars Erik. (1998) Terrain corrections to power H3 in gravimetric geoid determination. Journal of Geodesy. volum 72 (3).
Academic article
Nahavandchi, Hossein; Sjöberg, Lars Erik. (1998) Unification of vertical datums by GPS and gravimetric geoid models using modified Stokes formula. Marine Geodesy. volum 21 (4).
Academic article
Nahavandchi, Hossein. (1997) Connection of vertical datums using geoid models. Scientific and Technical Quarterly Journal of NCC. volum 8 (29).
Academic article
Nahavandchi, Hossein. (1997) Terrain effects in geoid determination over Iran. Scientific and Technical Quarterly Journal of NCC. volum 7 (28).
Academic article
Nahavandchi, Hossein. (1997) The Atmospheric Geoid effects over Iran. Scientific and Technical Quarterly Journal of NCC. volum 8 (29).
Academic article
Nahavandchi, Hossein. (1996) Determination of Spherical Harmonics coefficients by Integral Formula and Collocation method. Scientific and Technical Quarterly Journal of NCC. volum 6 (27).
Academic article
Nahavandchi, Hossein. (1995) External Gravity Potential of the Earth and the problem of spherical harmonics Convergency in Physical Geodesy. Scientific and Technical Quarterly Journal of NCC. volum 6 (23).
Academic article
Nahavandchi, Hossein. (1993) Geoid Determination with geometrical methods. Scientific and Technical Journal of NGO. volum 2 (6).
Academic article

Part of book/report

Safdari, Zohreh; Joodaki, Gholamreza; Nahavandchi, Hossein. (2022) A Technical Note on Least Squares Mascon Fitting to GRACE Satellite Data to Estimate Total Water Storage Changes in the Middle East. Satellite Monitoring of Water Resources in the Middle East.
Academic chapter/article/Conference paper
Shamshiri, Roghayeh; Nahavandchi, Hossein; Motagh, Mahdi. (2016) Deformation analysis of the Trondheim city from SAR Interferometry. Proceedings Living Planet Symposium 2016.
Academic chapter/article/Conference paper
Solheim, Dag; Omang, Ove Christian Dahl; Hunegnaw, Addisu; Drange, Helge; Johannessen, Johnny; siegismund, Frank; Nahavandchi, Hossein; Ghazavi, Kourosh; Pettersen, Bjørn Ragnvald; Lysaker, Dagny; Gidskehaug, Arne; Plag, Hans-Peter. (2007) The OCTAS poject, The geoid, the mean sea surface and the mean dynamic topography. Proceedings of the 3rd International GOCE User Workshop.
Academic chapter/article/Conference paper
Omang, Ove Christian Dahl; Solheim, Dag; Hunegnaw, Addisu; Lysaker, Dagny Iren; Ghazavi, K; Nahavandchi, Hossein. (2007) OCTAS with a focus on the importance of a high accuracy geoid. Gravity Field of the Earth, Proceedings of the 1st International Symposium of the International Gravity Field Service.
Academic chapter/article/Conference paper
Nahavandchi, Hossein; Soltanpour, Ali; Nyrnes, Erik. (2004) A New Gravimetric Geoidal Height Model over Norway Computed by the Least-Squares Modification Parameters. Gravity, Geoid, and Space Missions.
Other

Report

Nahavandchi, Hossein. (2006) HIGH-RESOLUTION GEOID DETERMINATION- IRanian Gravimetric Geoid 2005 (IRGG05). 2006.
Report
Nahavandchi, Hossein. (2001) Physical Geodesy. 2001.
Compendium
Nahavandchi, Hossein. (1998) Precise Gravimetric-GPS Geoid Determination with Improved Topographic Corrections Applid over Sweden. 1998.
Doctoral dissertation
Nahavandchi, Hossein. (1994) Compilation of 10' by 10' mean gravity anomalies in Iran. 1994.
Master thesis