Dr. Amir Ibrahim

Dr. Amir Ibrahim

  • RESEARCH SCIENTIST
  • 301.286.2371
  • NASA/GSFC
  • Mail Code: 616.2
  • Greenbelt , MD 20771
  • Employer: SCIENCE SYSTEMS AND APPLICATIONS INC
  • Brief Bio

    Dr. Ibrahim is currently a senior research scientist with SSAI at the Ocean Ecology Lab (616) in support of the Plankton, Aerosol, Clouds, 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.

    Dr. Ibrahim obtained his PhD. degree in February 2015 from the Electrical Engineering Dept. at the City College of the City University of New York (CCNY). His dissertation focused on ocean color remote sensing using polarimetric observation of light. He developed an inversion algorithm (c/a algorithm) based on Vector Radiative Transfer (VRT) models to retrieve macro- and micro-physical properties of oceanic hydrosols that helps in improving our understandings of the ocean geochemical properties and carbon cycle, in addition to improving the estimates of global chlorophyll and suspended minerals concentrations.
     

    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

    Pre-Aerosol, Cloud, and ocean Ecosystem (PACE)

    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)

    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

    7/2018 - Present

    Senior Research Scientist - Atmospheric Correction PACE Project Science Lead

    SSAI, NASA GSFC, Greenbelt, MD
    3/2017 - 7/2018

    Research Scientist

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

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

    6/2015 - 3/2017

    Postdoctoral Researcher

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

    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.

    1/2015 - 6/2015

    Post-doctoral Researcher

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

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

    Education

    PhD. in Electrical Engineering, CCNY

    Bachelor of Electrical Engineering, CCNY

    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

    10/12/2017 - 10/09/2020 Remote Sensing of Water Quality, UMBC, NASA NRA #: NNH16ZDA001N-RSWQ

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

    ; Co-I ; 0.1 FTE
    01/31/2018 The Science of TERRA, AQUA, and SUOMI NPP, NASA

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

    ; Co-I
    01/31/2018 The Science of TERRA, AQUA, and SUOMI NPP, NASA

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

    ; Co-I

    Selected Publications

    Refereed

    Frouin, R. J., B. A. Franz, A. Ibrahim, et al. K. Knobelspiesse, Z. Ahmad, B. Cairns, J. Chowdhary, H. M. Dierssen, J. Tan, O. Dubovik, X. Huang, A. B. Davis, O. Kalashnikova, D. R. Thompson, L. A. Remer, E. Boss, O. Coddington, P.-Y. Deschamps, B.-C. Gao, L. Gross, O. Hasekamp, A. Omar, B. Pelletier, D. Ramon, F. Steinmetz, and P.-W. Zhai. 2019. "Atmospheric Correction of Satellite Ocean-Color Imagery During the PACE Era." Frontiers in Earth Science, 7: [10.3389/feart.2019.00145]

    Remer, L. A., K. Knobelspiesse, P.-W. Zhai, et al. F. Xu, O. V. Kalashnikova, J. Chowdhary, O. Hasekamp, O. Dubovik, L. Wu, Z. Ahmad, E. Boss, B. Cairns, O. Coddington, A. B. Davis, H. M. Dierssen, D. J. Diner, B. Franz, R. Frouin, B.-C. Gao, A. Ibrahim, R. C. Levy, J. V. Martins, A. H. Omar, and O. Torres. 2019. "Retrieving Aerosol Characteristics From the PACE Mission, Part 2: Multi-Angle and Polarimetry." Frontiers in Environmental Science, 7: [10.3389/fenvs.2019.00094]

    Remer, L. A., A. B. Davis, S. Mattoo, et al. R. C. Levy, O. V. Kalashnikova, O. Coddington, J. Chowdhary, K. Knobelspiesse, X. Xu, Z. Ahmad, E. Boss, B. Cairns, H. M. Dierssen, D. J. Diner, B. Franz, R. Frouin, B.-C. Gao, A. Ibrahim, J. V. Martins, A. H. Omar, O. Torres, F. Xu, and P.-W. Zhai. 2019. "Retrieving Aerosol Characteristics From the PACE Mission, Part 1: Ocean Color Instrument." Frontiers in Earth Science, 7: [10.3389/feart.2019.00152]

    Gao, M., P.-W. Zhai, B. A. Franz, et al. Y. Hu, K. Knobelspiesse, P. J. Werdell, A. Ibrahim, B. Cairns, and A. Chase. 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 Discussions, 1-31 [10.5194/amt-2019-67]

    Ibrahim, A., B. A. Franz, Z. Ahmad, and S. W. Bailey. 2019. "Multiband Atmospheric Correction Algorithm for Ocean Color Retrievals." Frontiers in Earth Science, 7: [10.3389/feart.2019.00116]

    Jamet, C., A. Ibrahim, Z. Ahmad, et al. F. Angelini, M. Babin, M. J. Behrenfeld, E. Boss, B. Cairns, J. Churnside, J. Chowdhary, A. B. Davis, D. Dionisi, L. DuforĂȘt-Gaurier, B. Franz, R. Frouin, M. Gao, D. Gray, O. Hasekamp, X. He, C. Hostetler, O. V. Kalashnikova, K. Knobelspiesse, L. Lacour, H. Loisel, V. Martins, E. Rehm, L. Remer, I. Sanhaj, K. Stamnes, S. Stamnes, S. Victori, J. Werdell, and P.-W. Zhai. 2019. "Going Beyond Standard Ocean Color Observations: Lidar and Polarimetry." Frontiers in Marine Science, 6: [10.3389/fmars.2019.00251]

    Chowdhary, J., P. Zhai, E. Boss, et al. H. M. Dierssen, R. J. Frouin, A. Ibrahim, Z. Lee, L. A. Remer, M. Twardowski, F. Xu, X. Zhang, M. Ottaviani, W. R. Espinosa, and D. Ramon. 2019. "Radiative Transfer in Atmosphere-Ocean System." Frontiers in Earth Science, (In Press)

    Gao, M., P.-W. Zhai, B. Franz, et al. Y. Hu, K. Knobelspiesse, P. J. Werdell, A. Ibrahim, F. Xu, and B. Cairns. 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]

    Ottaviani, M., R. Foster, A. Gilerson, et al. A. Ibrahim, C. Carrizo, A. El-Habashi, B. Cairns, J. Chowdhary, C. Hostetler, J. Hair, S. Burton, Y. Hu, M. Twardowski, N. Stockley, D. Gray, W. Slade, and I. Cetinic. 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]

    Ibrahim, A., B. Franz, Z. Ahmad, et al. R. Healy, K. Knobelspiesse, B.-C. Gao, C. Proctor, and P.-W. Zhai. 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]

    Zhai, P.-W., K. Knobelspiesse, A. Ibrahim, et al. B. A. Franz, Y. Hu, M. Gao, and R. Frouin. 2017. "Water-leaving contribution to polarized radiation field over ocean." Optics Express, 25 (16): A689 [10.1364/oe.25.00a689]

    Ibrahim, A., A. Gilerson, J. Chowdhary, and S. Ahmed. 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]

    Gu, Y., C. Carrizo, A. A. Gilerson, et al. P. C. Brady, M. E. Cummings, M. S. Twardowski, J. M. Sullivan, A. I. Ibrahim, and G. W. Kattawar. 2016. "Polarimetric imaging and retrieval of target polarization characteristics in underwater environment." Applied Optics, 55 (3): 626--637 [10.1364/AO.55.000626]

    Brady, P. C., A. A. Gilerson, G. W. Kattawar, et al. J. M. Sullivan, M. S. Twardowski, H. M. Dierssen, M. Gao, K. Travis, R. I. Etheredge, A. Tonizzo, A. Ibrahim, C. Carrizo, Y. Gu, B. J. Russell, K. Mislinski, S. Zhao, and M. E. Cummings. 2015. "Open-ocean fish reveal an omnidirectional solution to camouflage in polarized environments." Science, 350 (6263): 965-969 [10.1126/science.aad5284]

    Ibrahim, A., A. Gilerson, T. Harmel, et al. A. Tonizzo, J. Chowdhary, and S. Ahmed. 2012. "The relationship between upwelling underwater polarization and attenuation/absorption ratio." Opt. Express, 20 (23): 25,662-25,680 [10.1364/OE.20.025662]

    Tonizzo, A., A. Gilerson, T. Harmel, et al. A. Ibrahim, J. Chowdhary, B. Gross, F. Moshary, and S. Ahmed. 2011. "Estimating particle composition and size distribution from polarized water-leaving radiance." Applied Optics, 50 (25): 5047-5058 [10.1364/AO.50.005047]

    Non-Refereed

    Foster, R., A. Ibrahim, A. Gilerson, et al. C. Carrizo, A. El-Habashi, and S. Ahmed. 2015. "Polarized above sea surface hyperspectral observations and their relationship with measured water properties." Hyperspectral Imaging and Sounding of the Environment HT3B--4.

    Gilerson, A., C. Carrizo, A. Tonizzo, et al. A. Ibrahim, A. El-Habashi, R. Foster, and S. Ahmed. 2013. "Polarimetric imaging of underwater targets." SPIE Defense, Security, and Sensing 872403--872403.

    Ahmed, S., A. Tonizzo, A. Ibrahim, et al. A. Gilerson, B. Gross, and F. Moshary. 2012. "Algal fluorescence: impact and potential for retrieval from measurements of the underwater degree of polarization." SPIE Remote Sensing 85320I--85320I.

    Gilerson, A., A. Ibrahim, T. Harmel, A. Tonizzo, and S. Ahmed. 2012. "Polarization techniques for the retrieval of water parameters from above and below water polarimetric observations." Proc. of SPIE Vol 8372: 83720T--1.

    Harmel, T., A. Tonizzo, A. Ibrahim, et al. A. Gilerson, J. Chowdhary, and S. Ahmed. 2011. "Measuring underwater polarization field from above-water hyperspectral instrumentation for water composition retrieval." SPIE Remote Sensing 817509--817509.

    Ibrahim, A., T. Harmel, A. Tonizzo, et al. I. Ioannou, A. Gilerson, and S. Ahmed. 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.

    Hlaing, S., T. Harmel, A. Ibrahim, et al. I. Ioannou, A. Tonizzo, A. Gilerson, and S. Ahmed. 2010. "Validation of ocean color satellite sensors using coastal observational platform in Long Island Sound." Remote Sensing 782504--782504.

    Brief Bio

    Dr. Ibrahim is currently a senior research scientist with SSAI at the Ocean Ecology Lab (616) in support of the Plankton, Aerosol, Clouds, 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.

    Dr. Ibrahim obtained his PhD. degree in February 2015 from the Electrical Engineering Dept. at the City College of the City University of New York (CCNY). His dissertation focused on ocean color remote sensing using polarimetric observation of light. He developed an inversion algorithm (c/a algorithm) based on Vector Radiative Transfer (VRT) models to retrieve macro- and micro-physical properties of oceanic hydrosols that helps in improving our understandings of the ocean geochemical properties and carbon cycle, in addition to improving the estimates of global chlorophyll and suspended minerals concentrations.
     

    Selected Publications

    Refereed

    Frouin, R. J., B. A. Franz, A. Ibrahim, et al. K. Knobelspiesse, Z. Ahmad, B. Cairns, J. Chowdhary, H. M. Dierssen, J. Tan, O. Dubovik, X. Huang, A. B. Davis, O. Kalashnikova, D. R. Thompson, L. A. Remer, E. Boss, O. Coddington, P.-Y. Deschamps, B.-C. Gao, L. Gross, O. Hasekamp, A. Omar, B. Pelletier, D. Ramon, F. Steinmetz, and P.-W. Zhai. 2019. "Atmospheric Correction of Satellite Ocean-Color Imagery During the PACE Era." Frontiers in Earth Science 7 [10.3389/feart.2019.00145]

    Remer, L. A., K. Knobelspiesse, P.-W. Zhai, et al. F. Xu, O. V. Kalashnikova, J. Chowdhary, O. Hasekamp, O. Dubovik, L. Wu, Z. Ahmad, E. Boss, B. Cairns, O. Coddington, A. B. Davis, H. M. Dierssen, D. J. Diner, B. Franz, R. Frouin, B.-C. Gao, A. Ibrahim, R. C. Levy, J. V. Martins, A. H. Omar, and O. Torres. 2019. "Retrieving Aerosol Characteristics From the PACE Mission, Part 2: Multi-Angle and Polarimetry." Frontiers in Environmental Science 7 [10.3389/fenvs.2019.00094]

    Remer, L. A., A. B. Davis, S. Mattoo, et al. R. C. Levy, O. V. Kalashnikova, O. Coddington, J. Chowdhary, K. Knobelspiesse, X. Xu, Z. Ahmad, E. Boss, B. Cairns, H. M. Dierssen, D. J. Diner, B. Franz, R. Frouin, B.-C. Gao, A. Ibrahim, J. V. Martins, A. H. Omar, O. Torres, F. Xu, and P.-W. Zhai. 2019. "Retrieving Aerosol Characteristics From the PACE Mission, Part 1: Ocean Color Instrument." Frontiers in Earth Science 7 [10.3389/feart.2019.00152]

    Gao, M., P.-W. Zhai, B. A. Franz, et al. Y. Hu, K. Knobelspiesse, P. J. Werdell, A. Ibrahim, B. Cairns, and A. Chase. 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 Discussions 1-31 [10.5194/amt-2019-67]

    Ibrahim, A., B. A. Franz, Z. Ahmad, and S. W. Bailey. 2019. "Multiband Atmospheric Correction Algorithm for Ocean Color Retrievals." Frontiers in Earth Science 7 [10.3389/feart.2019.00116]

    Jamet, C., A. Ibrahim, Z. Ahmad, et al. F. Angelini, M. Babin, M. J. Behrenfeld, E. Boss, B. Cairns, J. Churnside, J. Chowdhary, A. B. Davis, D. Dionisi, L. DuforĂȘt-Gaurier, B. Franz, R. Frouin, M. Gao, D. Gray, O. Hasekamp, X. He, C. Hostetler, O. V. Kalashnikova, K. Knobelspiesse, L. Lacour, H. Loisel, V. Martins, E. Rehm, L. Remer, I. Sanhaj, K. Stamnes, S. Stamnes, S. Victori, J. Werdell, and P.-W. Zhai. 2019. "Going Beyond Standard Ocean Color Observations: Lidar and Polarimetry." Frontiers in Marine Science 6 [10.3389/fmars.2019.00251]

    Chowdhary, J., P. Zhai, E. Boss, et al. H. M. Dierssen, R. J. Frouin, A. Ibrahim, Z. Lee, L. A. Remer, M. Twardowski, F. Xu, X. Zhang, M. Ottaviani, W. R. Espinosa, and D. Ramon. 2019. "Radiative Transfer in Atmosphere-Ocean System." Frontiers in Earth Science (In Press)

    Gao, M., P.-W. Zhai, B. Franz, et al. Y. Hu, K. Knobelspiesse, P. J. Werdell, A. Ibrahim, F. Xu, and B. Cairns. 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]

    Ottaviani, M., R. Foster, A. Gilerson, et al. A. Ibrahim, C. Carrizo, A. El-Habashi, B. Cairns, J. Chowdhary, C. Hostetler, J. Hair, S. Burton, Y. Hu, M. Twardowski, N. Stockley, D. Gray, W. Slade, and I. Cetinic. 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]

    Ibrahim, A., B. Franz, Z. Ahmad, et al. R. Healy, K. Knobelspiesse, B.-C. Gao, C. Proctor, and P.-W. Zhai. 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]

    Zhai, P.-W., K. Knobelspiesse, A. Ibrahim, et al. B. A. Franz, Y. Hu, M. Gao, and R. Frouin. 2017. "Water-leaving contribution to polarized radiation field over ocean." Optics Express 25 (16): A689 [10.1364/oe.25.00a689]

    Ibrahim, A., A. Gilerson, J. Chowdhary, and S. Ahmed. 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]

    Gu, Y., C. Carrizo, A. A. Gilerson, et al. P. C. Brady, M. E. Cummings, M. S. Twardowski, J. M. Sullivan, A. I. Ibrahim, and G. W. Kattawar. 2016. "Polarimetric imaging and retrieval of target polarization characteristics in underwater environment." Applied Optics 55 (3): 626--637 [10.1364/AO.55.000626]

    Brady, P. C., A. A. Gilerson, G. W. Kattawar, et al. J. M. Sullivan, M. S. Twardowski, H. M. Dierssen, M. Gao, K. Travis, R. I. Etheredge, A. Tonizzo, A. Ibrahim, C. Carrizo, Y. Gu, B. J. Russell, K. Mislinski, S. Zhao, and M. E. Cummings. 2015. "Open-ocean fish reveal an omnidirectional solution to camouflage in polarized environments." Science 350 (6263): 965-969 [10.1126/science.aad5284]

    Ibrahim, A., A. Gilerson, T. Harmel, et al. A. Tonizzo, J. Chowdhary, and S. Ahmed. 2012. "The relationship between upwelling underwater polarization and attenuation/absorption ratio." Opt. Express 20 (23): 25,662-25,680 [10.1364/OE.20.025662]

    Tonizzo, A., A. Gilerson, T. Harmel, et al. A. Ibrahim, J. Chowdhary, B. Gross, F. Moshary, and S. Ahmed. 2011. "Estimating particle composition and size distribution from polarized water-leaving radiance." Applied Optics 50 (25): 5047-5058 [10.1364/AO.50.005047]

    Non-Refereed

    Foster, R., A. Ibrahim, A. Gilerson, et al. C. Carrizo, A. El-Habashi, and S. Ahmed. 2015. "Polarized above sea surface hyperspectral observations and their relationship with measured water properties." Hyperspectral Imaging and Sounding of the Environment HT3B--4

    Gilerson, A., C. Carrizo, A. Tonizzo, et al. A. Ibrahim, A. El-Habashi, R. Foster, and S. Ahmed. 2013. "Polarimetric imaging of underwater targets." SPIE Defense, Security, and Sensing 872403--872403

    Ahmed, S., A. Tonizzo, A. Ibrahim, et al. A. Gilerson, B. Gross, and F. Moshary. 2012. "Algal fluorescence: impact and potential for retrieval from measurements of the underwater degree of polarization." SPIE Remote Sensing 85320I--85320I

    Gilerson, A., A. Ibrahim, T. Harmel, A. Tonizzo, and S. Ahmed. 2012. "Polarization techniques for the retrieval of water parameters from above and below water polarimetric observations." Proc. of SPIE Vol 8372 83720T--1

    Harmel, T., A. Tonizzo, A. Ibrahim, et al. A. Gilerson, J. Chowdhary, and S. Ahmed. 2011. "Measuring underwater polarization field from above-water hyperspectral instrumentation for water composition retrieval." SPIE Remote Sensing 817509--817509

    Ibrahim, A., T. Harmel, A. Tonizzo, et al. I. Ioannou, A. Gilerson, and S. Ahmed. 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

    Hlaing, S., T. Harmel, A. Ibrahim, et al. I. Ioannou, A. Tonizzo, A. Gilerson, and S. Ahmed. 2010. "Validation of ocean color satellite sensors using coastal observational platform in Long Island Sound." Remote Sensing 782504--782504

                                                                                                                                                                                            
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