NASA Logo in the header
Sciences and Exploration Directorate

Amir Ibrahim

(Research AST, Oceanographic Studies)

Amir Ibrahim's Contact Card & Information.
Email: amir.ibrahim@nasa.gov
Phone: 301.286.7953
Org Code: 616
Address:
NASA/GSFC
 Mail Code 616.2
 Greenbelt, MD 20771
Employer:
NASA

Missions & Projects

Brief Bio

Dr. Amir Ibrahim is a scientist working at the Ocean Ecology Lab (OEL) within the NASA Goddard Space Flight Center (GSFC). He holds a key role in leading the development of atmospheric correction algorithms for NASA's Plankton, Aerosol, Clouds, ocean Ecosystem (PACE) mission. As a member of the PACE project science team, Dr. Ibrahim is actively involved in researching and assessing atmospheric correction methods for deriving ocean color data from the Ocean Color Instrument (OCI) in conjunction with multi-angle polarimeters (SPEXone and HARP2).

In addition to his contributions to the PACE mission, Dr. Ibrahim also serves as the instrument scientist for the ocean color instrument (OCX) of the NASA/NOAA GeoXO mission.

Dr. Ibrahim's academic journey includes the successful completion of his Ph.D. degree in February 2015 from the Electrical Engineering Department at the City College of the City University of New York (CCNY). During his doctoral research, he focused on ocean color remote sensing using polarimetric observations of light. Notably, he developed an innovative inversion algorithm known as the "c/a algorithm" based on Vector Radiative Transfer (VRT) models. This algorithm allows for the retrieval of macro- and micro-physical properties of oceanic hydrosols, which significantly enhances our understanding of ocean geochemical properties, carbon cycles, and the estimation of global chlorophyll and suspended mineral concentrations.

Dr. Amir Ibrahim's work in the field of ocean color remote sensing and atmospheric correction plays a vital role in advancing our knowledge of marine ecosystems and environmental monitoring from space-based platforms.

Research Interests

Vector Radiative Transfer modeling, polarimetric remote sensing, hyperspectral remote sensing

• Inversion of the vector radiative transfer equation in the coupled ocean-atmosphere system.
• Retrieval of useful optical and microphysical properties of aerosols/hydrosols using the polarization of light.
• Improvement of atmospheric correction procedures for ocean color remote sensing.
• Assessment of the impact of atmospheric aerosols on the observed spectral scalar and polarized radiance at both sea surface level and at top of the atmosphere.
• Hyperspectral data processing and analysis of underwater, shipborne, airborne, and satellite measurements.
 

Current Projects

Ocean color instrument (OCX) on Geostationary Extended Observations (GeoXO)

Technology & Missions

Instrument scientist for the ocean color instrument (OCX) on the NASA/NOAA GeoXO mission.

Plankton, Aerosol, Cloud, and ocean Ecosystem (PACE)

Remote Sensing

Develop and evaluate atmospheric correction methods for derivation of ocean color from a hyperspectral space-borne and air-borne radiometer and combined multi-angle polarimeter.
 

The Hyperspectral Imager for the Coastal Ocean (HICO)

Remote Sensing

Develop and validate a hyperspectral atmospheric correction algorithm of molecular and aerosol scattering and compensate for gaseous absorption in the atmosphere (such as water vapor, oxygen, and ozone) for the HICO sensor in order to retrieve a hyperspectral remote sensing reflectance to derive ocean color products.

Positions/Employment

Research Oceanographer

Ocean Ecology Laboratory, NASA Goddard Space Flight Center - Greenbelt, MD

March 2021 - Present

Senior Research Scientist - Atmospheric Correction PACE Project Science Lead

SSAI - NASA GSFC, Greenbelt, MD

July 2018 - March 2021

Research Scientist

Universities Space Research Association (USRA) / NASA GSFC - Greenbelt, MD

March 2017 - July 2018

Atmospheric correction for Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission

Postdoctoral Researcher

Universities Space Research Association (USRA) / NASA GSFC - Greenbelt

June 2015 - March 2017

Support of the Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission's Science Team activities to develop and evaluate atmospheric correction methods for derivation of ocean color from a hyperspectral radiometer and combined multi-angle polarimeter.

Postdoctoral Researcher

Research Foundation of The City University of New York - New York, NY

January 2015 - June 2015

Polarimetric remote sensing algorithm development and validation with in-situ optics

Education

PhD. in Electrical Engineering, CCNY

Bachelor of Electrical Engineering, CCNY

Professional Societies

American Geophysical Union

2015 - Present

Institute of Electrical and Electronics Engineers

2009 - Present

Awards

• Honorary Mention awarded for Best Student Paper titled “Retrievals of the Attenuation and Scattering Coefficients of Marine Particles Using the Polarization of Light” from the oceanography society at the Ocean Optics 2014 conference, Portland, Maine.
• Certificate of Distinguished Achievement in Academic Excellence, NOAA-CREST Institute, 2013, The City College of New York.
• Honorary Mention awarded for Best Student Paper titled “The Relationship between Upwelling Polarized Radiance and In-Water Attenuation to Absorption Ratio” from the oceanography society at the Ocean Optics 2012 conference, Glasgow, Scotland.
• Graduate Teaching Fellowship, 2011-2013.

Grants

Atmospheric correction for complex scenes using co-located polarimetric and ocean color observations.

Remote Sensing of Water Quality - UMBC (NNH16ZDA001N-RSWQ) - Awarded: 2017-07-14


Dates: 2017-10-12  - 2020-10-09

Coverage: 0.1

Advancing the Quality and Continuity of Marine Remote Sensing Reflectance and Derived Ocean Color Products from MODIS to VIIRS

The Science of TERRA, AQUA, and SUOMI NPP - NASA - Awarded: 2018-01-31


Dates:  - 

Joint MISR/MODIS ocean color atmospheric correction with a new algorithm that utilizes reflected sun glint

The Science of TERRA, AQUA, and SUOMI NPP - NASA - Awarded: 2018-01-31


Dates:  - 

Selected Publications

Refereed

2025. "Annual periodicity in ocean color observations across diverse oceanic regions.", Applied Optics, 64 (25): 7376-7395 [10.1364/ao.566299] [Journal Article/Letter]

2025. "A practical guide to coding line-by-line trace gas absorption in Earth's atmosphere.", Journal of Quantitative Spectroscopy and Radiative Transfer, 337 109345 [10.1016/j.jqsrt.2025.109345] [Journal Article/Letter]

2025. "Exploiting Machine Learning to Develop Ocean Color Retrievals from the Tropospheric Emissions: Monitoring of Pollution Instrument.", ESS Open Archive, [10.22541/essoar.174326553.36262101/v1] [Journal Article/Letter]

2024. "Uncertainties in radiometric measurements of the ocean surface from above water and helicopter hyperspectral and polarimetric observations.", Applied Optics, [10.1364/ao.527229] [Journal Article/Letter]

2024. "Anomalous trends in global ocean carbon concentrations following the 2022 eruptions of Hunga Tonga-Hunga Ha’apai.", Communications Earth & Environment, 5 (1): 247 [10.1038/s43247-024-01421-8] [Journal Article/Letter]

2024. "Spectral correlation in MODIS water-leaving reflectance retrieval uncertainty.", Optics Express, 32 (2): 2490 [10.1364/oe.502561] [Journal Article/Letter]

2024. "Assessing the utility of high spectral resolution lidar for measuring particulate backscatter in the ocean and evaluating satellite ocean color retrievals.", Remote Sensing of Environment, 300 113898 [10.1016/j.rse.2023.113898] [Journal Article/Letter]

2023. "Simultaneous retrieval of aerosol and ocean properties from PACE HARP2 with uncertainty assessment using cascading neural network radiative transfer models.", Atmospheric Measurement Techniques, 16 (23): [https://doi.org/10.5194/amt-16-5863-2023] [Journal Article/Letter]

2023. "A neural network approach to the estimation of in-water attenuation to absorption ratios from PACE mission measurements.", Frontiers in Remote Sensing, 4 [10.3389/frsen.2023.1060908] [Journal Article/Letter]

2023. "Optimizing retrieval spaces of bio-optical models for remote sensing of ocean color.", Applied Optics, 62 (13): 3299 [10.1364/ao.484082] [Journal Article/Letter]

2023. "The CHROMA cloud-top pressure retrieval algorithm for the Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) satellite mission.", Atmospheric Measurement Techniques, 16 (4): 969-996 [10.5194/amt-16-969-2023] [Journal Article/Letter]

2022. "Effective uncertainty quantification for multi-angle polarimetric aerosol remote sensing over ocean.", Atmos. Meas. Tech., 15 (16): 4859–4879 [10.5194/amt-15-4859-2022] [Journal Article/Letter]

2022. "Estimating pixel-level uncertainty in ocean color retrievals from MODIS.", Optics Express, 30 (17): 31415 [10.1364/oe.460735] [Journal Article/Letter]

2022. "Optimal Estimation Framework for Ocean Color Atmospheric Correction and Pixel-level Uncertainty Quantification.", Applied Optics, Vol. 61 No. 20 [10.1364/ao.461861] [Journal Article/Letter]

2022. "Determining the Primary Sources of Uncertainty in Retrieval of Marine Remote Sensing Reflectance From Satellite Ocean Color Sensors.", Frontiers in Remote Sensing, 3 [10.3389/frsen.2022.857530] [Journal Article/Letter]

2022. "A Radiative Transfer Simulator for PACE: Theory and Applications.", Frontiers in Remote Sensing, 3 [10.3389/frsen.2022.840188] [Journal Article/Letter]

2021. "Adaptive Data Screening for Multi-Angle Polarimetric Aerosol and Ocean Color Remote Sensing Accelerated by Deep Learning.", Frontiers in Remote Sensing, 2 [10.3389/frsen.2021.757832] [Journal Article/Letter]

2021. "A practical guide to writing a radiative transfer code.", Computer Physics Communications, 271 108198 [10.1016/j.cpc.2021.108198] [Journal Article/Letter]

2021. "Seasonal bias in global ocean color observations.", Applied Optics, 60 (23): 6978 [10.1364/ao.426137] [Journal Article/Letter]

2021. "Efficient multi-angle polarimetric inversion of aerosols and oceancolor powered by a deep neural network forward model.", Atmospheric Measurement Techniques, 14 (6): 4083–4110 [https://doi.org/10.5194/amt-14-4083-2021] [Journal Article/Letter]

2021. "Analysis of simultaneous aerosol and ocean glint retrieval using multi-angle observations.", Atmospheric Measurement Techniques, 14 3233-3252 [10.5194/amt-14-3233-2021] [Journal Article/Letter]

2021. "Atmospheric correction over the ocean for hyperspectral radiometers using multi-angle polarimetric retrievals.", Optics Express, 29 (3): 4504 [10.1364/oe.408467] [Journal Article/Letter]

2020. "Particulate backscattering in the global ocean: A comparison of independent assessments.", Geophysical Research Letters, [10.1029/2020gl090909] [Journal Article/Letter]

2020. "Inversion of multiangular polarimetric measurements from the ACEPOL campaign: an application of improving aerosol property and hyperspectral ocean color retrievals.", Atmospheric Measurement Techniques, 13 3939–3956 [10.5194/amt-13-3939-2020] [Journal Article/Letter]

2020. "Hyperspectral polarimetric imaging of the water surface and retrieval of water optical parameters from multi-angular polarimetric data.", Applied Optics, 59 (10): C8 [10.1364/ao.59.0000c8] [Journal Article/Letter]

2019. "Atmospheric Correction of Satellite Ocean-Color Imagery During the PACE Era.", Frontiers in Earth Science, 7 [10.3389/feart.2019.00145] [Journal Article/Letter]

2019. "Retrieving Aerosol Characteristics From the PACE Mission, Part 2: Multi-Angle and Polarimetry.", Frontiers in Environmental Science, 7 [10.3389/fenvs.2019.00094] [Journal Article/Letter]

2019. "Retrieving Aerosol Characteristics From the PACE Mission, Part 1: Ocean Color Instrument.", Frontiers in Earth Science, 7 [10.3389/feart.2019.00152] [Journal Article/Letter]

2019. "Inversion of multi-angular polarimetric measurements over open and coastal ocean waters: a joint retrieval algorithm for aerosol and water leaving radiance properties.", Atmospheric Measurement Techniques, 12 (7): 3921–3941 [10.5194/amt-12-3921-2019] [Journal Article/Letter]

2019. "Modeling Atmosphere-Ocean Radiative Transfer: A PACE Mission Perspective.", Frontiers in Earth Science, 7 100 pp. [10.3389/feart.2019.00100] [Journal Article/Letter]

2019. "Multiband Atmospheric Correction Algorithm for Ocean Color Retrievals.", Frontiers in Earth Science, 7 [10.3389/feart.2019.00116] [Journal Article/Letter]

2019. "Going Beyond Standard Ocean Color Observations: Lidar and Polarimetry.", Frontiers in Marine Science, 6 [10.3389/fmars.2019.00251] [Journal Article/Letter]

2018. "Retrieval of aerosol properties and water-leaving reflectance from multi-angular polarimetric measurements over coastal waters.", Optics Express, 26 (7): 8968 [10.1364/oe.26.008968] [Journal Article/Letter]

2018. "Airborne and shipborne polarimetric measurements over open ocean and coastal waters: Intercomparisons and implications for spaceborne observations.", Remote Sensing of Environment, 206 375-390 [10.1016/j.rse.2017.12.015] [Journal Article/Letter]

2018. "Atmospheric correction for hyperspectral ocean color retrieval with application to the Hyperspectral Imager for the Coastal Ocean (HICO).", Remote Sensing of Environment, 204 60-75 [10.1016/j.rse.2017.10.041] [Journal Article/Letter]

2017. "Water-leaving contribution to polarized radiation field over ocean.", Optics Express, 25 (16): A689 [10.1364/oe.25.00a689] [Journal Article/Letter]

2016. "Retrieval of macro- and micro-physical properties of oceanic hydrosols from polarimetric observations.", Remote Sensing of Environment, 186 548-566 [10.1016/j.rse.2016.09.004] [Journal Article/Letter]

2016. "Polarimetric imaging and retrieval of target polarization characteristics in underwater environment.", Applied Optics, 55 (3): 626--637 [10.1364/AO.55.000626] [Journal Article/Letter]

2015. "Open-ocean fish reveal an omnidirectional solution to camouflage in polarized environments.", Science, 350 (6263): 965-969 [10.1126/science.aad5284] [Journal Article/Letter]

2012. "The relationship between upwelling underwater polarization and attenuation/absorption ratio.", Opt. Express, 20 (23): 25,662-25,680 [10.1364/OE.20.025662] [Journal Article/Letter]

2011. "Estimating particle composition and size distribution from polarized water-leaving radiance.", Applied Optics, 50 (25): 5047-5058 [10.1364/AO.50.005047] [Journal Article/Letter]

Non-Refereed

2024. "Life after launch: a snapshot of the first six months of NASA’s plankton, aerosol, cloud, ocean ecosystem (PACE) mission.", Sensors, Systems, and Next-Generation Satellites XXVIII, 14 [10.1117/12.3033830] [Proceedings]

2015. "Polarized above sea surface hyperspectral observations and their relationship with measured water properties.", Hyperspectral Imaging and Sounding of the Environment, HT3B--4 [Proceedings]

2013. "Polarimetric imaging of underwater targets.", SPIE Defense, Security, and Sensing, 872403--872403 [Proceedings]

2012. "Algal fluorescence: impact and potential for retrieval from measurements of the underwater degree of polarization.", SPIE Remote Sensing, 85320I--85320I [Proceedings]

2012. "Polarization techniques for the retrieval of water parameters from above and below water polarimetric observations.", Proc. of SPIE Vol, 8372 83720T--1 [Journal Article/Letter]

2011. "Measuring underwater polarization field from above-water hyperspectral instrumentation for water composition retrieval.", SPIE Remote Sensing, 817509--817509 [Proceedings]

2011. "Exploring the relation between polarized light fields and physical-optical characteristics of the ocean for Remote Sensing applications.", SPIE Optical Engineering+ Applications, 81600H--81600H [Proceedings]

2010. "Validation of ocean color satellite sensors using coastal observational platform in Long Island Sound.", Remote Sensing, 782504--782504 [Proceedings]

Contact Us

For general inquiries about the Sciences and Exploration Directorate.

Jocelyn Lynch

Project Support Specialist

301-286-6066 jocelyn.m.lynch@nasa.gov
Ellie Jeffries

Project Support Specialist

301-286-6066 ellie.jeffries@nasa.gov
Technical issues with this website may be reported to ben.pelletier@nasa.gov.
General inquiries about the scientific programs at NASA's Goddard Space Flight Center may be directed to the Center Office of Communications at 1.301.286.8955.