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Santha Akella

Photo of SANTHA AKELLA

Santha Akella

  • RESEARCH AST, OCEANOGRAPHIC STUDIES
  • 301.614.5687
  • NASA/GSFC
  • Mail Code: 610.1
  • Greenbelt , MD 20771
  • Employer: NASA

    • Brief Bio

    Dr. Akella works at the Global Modeling and Assimilation Office (GMAO). His research focuses on the development, testing and operational integration of the next generation atmosphere-ocean coupled, Integrated Earth Analysis System (IESA), with emphasis on the ocean and ocean-atmosphere coupling.

    Education

    Positions/Employment

    10/2018 - Present

    Research Oceanographer

    GSFC, NASA
    12/2010 - 10/2018

    Support Scientist

    SSAI Inc., GSFC, NASA
    4/2008 - 11/2010

    Postdoc Researcher

    Johns Hopkins Univ., Baltimore, MD
    4/2007 - 3/2008

    Postdoc Researcher

    Texas A&M Univ., College Station, TX
    6/2006 - 3/2007

    Postdoc Researcher

    University of Pennsylvania, Philadelphia, PA
    8/2000 - 5/2006

    Teaching and Graduate Research Assistant

    Florida State Univ., Tallahassee, FL

    Publications

    Refereed

    Luo, B., P. J. Minnett, M. Szczodrak, and S. Akella. 2022. "Regional and Seasonal Variability of the Oceanic Thermal Skin Effect." Journal of Geophysical Research: Oceans, 127 (5): [10.1029/2022jc018465]

    Luo, B., P. J. Minnett, P. Zuidema, N. R. Nalli, and S. Akella. 2021. "Saharan dust effects on North Atlantic sea‐surface skin temperatures." Journal of Geophysical Research: Oceans, [10.1029/2021jc017282]

    Gentemann, C. L., J. P. Scott, P. L. Mazzini, et al. C. Pianca, S. Akella, P. J. Minnett, P. Cornillon, B. Fox-Kemper, I. Cetinić, T. M. Chin, J. Gomez-Valdes, J. Vazquez-Cuervo, V. Tsontos, L. Yu, R. Jenkins, S. De Halleux, D. Peacock, and N. Cohen. 2020. "Saildrone: adaptively sampling the marine environment." Bulletin of the American Meteorological Society, 101 (6): E744–E762 [10.1175/bams-d-19-0015.1]

    Penny, S. G., S. Akella, M. A. Balmaseda, et al. P. Browne, J. A. Carton, M. Chevallier, F. Counillon, C. Domingues, S. Frolov, P. Heimbach, P. Hogan, I. Hoteit, D. Iovino, P. Laloyaux, M. J. Martin, S. Masina, A. M. Moore, P. de Rosnay, D. Schepers, B. M. Sloyan, A. Storto, A. Subramanian, S. Nam, F. Vitart, C. Yang, Y. Fujii, H. Zuo, T. O’Kane, P. Sandery, T. Moore, and C. C. Chapman. 2019. "Observational Needs for Improving Ocean and Coupled Reanalysis, S2S Prediction, and Decadal Prediction." Frontiers in Marine Science, 6: [10.3389/fmars.2019.00391]

    Moore, A. M., M. J. Martin, S. Akella, et al. H. G. Arango, M. Balmaseda, L. Bertino, S. Ciavatta, B. Cornuelle, J. Cummings, S. Frolov, P. Lermusiaux, P. Oddo, P. R. Oke, A. Storto, A. Teruzzi, A. Vidard, and A. T. Weaver. 2019. "Synthesis of Ocean Observations Using Data Assimilation for Operational, Real-Time and Reanalysis Systems: A More Complete Picture of the State of the Ocean." Frontiers in Marine Science, 6: [10.3389/fmars.2019.00090]

    Gentemann, C. L., and S. Akella. 2018. "Evaluation of NASA GEOS-ADAS Modeled Diurnal Warming Through Comparisons to SEVIRI and AMSR2 SST Observations." Journal of Geophysical Research: Oceans, [10.1002/2017jc013186]

    Gelaro, R., W. McCarty, M. J. Suárez, et al. R. Todling, A. Molod, L. Takacs, C. Randles, A. Darmenov, M. G. Bosilovich, R. Reichle, K. Wargan, L. Coy, R. Cullather, C. Draper, S. Akella, V. Buchard, A. Conaty, A. da Silva, W. Gu, G.-K. Kim, R. Koster, R. Lucchesi, D. Merkova, J. E. Nielsen, G. Partyka, S. Pawson, W. Putman, M. Rienecker, S. D. Schubert, M. Sienkiewicz, and B. Zhao. 2017. "The Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2)." Journal of Climate, 30: 5419–5454 [10.1175/jcli-d-16-0758.1]

    Akella, S., R. Todling, and M. J. Suarez. 2017. "Assimilation for skin SST in the NASA GEOS atmospheric data assimilation system." Quarterly Journal of the Royal Meteorological Society, 143 (703): 1032-1046 [10.1002/qj.2988]

    Brassington, G., M. Martin, H. Tolman, et al. S. Akella, M. Balmeseda, C. Chambers, E. Chassignet, J. Cummings, Y. Drillet, P. Jansen, P. Laloyaux, D. Lea, A. Mehra, I. Mirouze, H. Ritchie, G. Samson, P. Sandery, G. Smith, M. Suarez, and R. Todling. 2015. "Progress and challenges in short- to medium-range coupled prediction." Journal of Operational Oceanography, 8 (sup2): s239-s258 [10.1080/1755876x.2015.1049875]

    Vernieres, G. R., R. M. Kovach, C. L. Keppenne, et al. S. R. Akella, L. Brucker, and E. P. Dinnat. 2014. "The impact of the assimilation of Aquarius sea surface salinity data in the GEOS ocean data assimilation system." J. Geophys. Res. Oceans, 119 (10): 6974-6987 [10.1002/2014JC010006]

    Akella, S. R. 2011. "Reservoir Multiscale Data Assimilation Using the Ensemble Kalman Filter." Applied Mathematics, 02 (02): 165-180 [10.4236/am.2011.22019]

    Chen, X., S. Akella, and I. M. Navon. 2011. "A dual-weighted trust-region adaptive POD 4-D Var applied to a finite-volume shallow water equations model on the sphere." International Journal for Numerical Methods in Fluids, 68 (3): 377-402 [10.1002/fld.2523]

    Akella, S., A. Datta-Gupta, and Y. Efendiev. 2011. "ASSIMILATION OF COARSE-SCALEDATAUSINGTHE ENSEMBLE KALMAN FILTER." International Journal for Uncertainty Quantification, 1 (1): 49-76 [10.1615/int.j.uncertaintyquantification.v1.i1.40]

    Akella, S., and I. M. Navon. 2008. "Different approaches to model error formulation in 4D-Var: a study with high-resolution advection schemes." Tellus A, 61 (1): 112-128 [10.1111/j.1600-0870.2008.00362.x]

    Akella, S., and I. M. Navon. 2005. "A comparative study of the performance of high resolution advection schemes in the context of data assimilation." International Journal for Numerical Methods in Fluids, 51 (7): 719-748 [10.1002/fld.1145]

    Mandal, N., and S. R. Akella. 2000. "A Finite Difference Model for Prediction of Welding Thermal History (Part 1)." Journal of the Mechanical Behavior of Materials, 11 (5): [10.1515/jmbm.2000.11.5.381]

    Non-Refereed

    Akella, S., and M. J. Suarez. 2018. "The Atmosphere-Ocean Interface Layer of NASA’s Goddard Earth Observing System Model and Data Assimilation System." NASA Technical Report Series on Global Modeling and Data Assimilation, NASA/TM-2018-104606 51: 42pp. [Full Text (Link)]

    Kim, J. G., S. R. Akella, A. M. Da Silva, R. Todling, and W. R. Mccarty. 2018. "Preliminary evaluation of influence of aerosols on the simulation of brightness temperature in the NASA’s Goddard Earth Observing System Atmospheric Data Assimilation System." NASA Technical Report Series on Global Modeling and Data Assimilation, NASA/TM-2018-104606 49: 44pp [Full Text (Link)]

    Akella, S. R., R. Todling, and M. J. Suarez. 2016. "Estimation of the Ocean Skin Temperature using the NASA GEOS Atmospheric Data Assimilation System." NASA Technical Report Series on Global Modeling and Data Assimilation, NASA/TM-2016-10460 44: 88pp.

    Bosilovich, M. G., S. R. Akella, L. Coy, et al. R. I. Cullather, C. S. Draper, R. Gelaro, R. M. Kovach, Q. Liu, A. M. Molod, P. M. Norris, K. Wargan, C. Yang, R. H. Reichle, L. L. Takacs, Y. V. Vikhliaev, S. C. Bloom, A. Collow, S. Firth, G. J. Labow, G. S. Partyka, S. Pawson, O. Reale, S. D. Schubert, and M. J. Suarez. 2015. "MERRA-2: Initial Evaluation of the Climate." NASA Technical Report Series on Global Modeling and Data Assimilation 43 (NASA/TM–2015–10): 139 pp.

    Awards

    • NASA Honor Award, Group Achievement Award, MERRA-2 Science Team, August, 2019
    • Travel award to present invited talk ``Skin SST assimilation using GEOS-ADAS" at the International workshop on coupled data assimilation, Toulouse, France, October, 2016 [http://www.meteo.fr/cic/meetings/2016/CDAW2016/]
    • Scientific achievement award for successfully implementing skin temperature analysis in GEOS-5, January, 2016

     

    Grants

    03/17/2017 Implementing a physically motivated source of sea salt for aerosol and cloud applications in GEOS-5 through improved wind-wave coupling, NASA
    No cost collaborator
    04/02/2020 Effectively constraining both atmosphere and ocean components in an Integrated Earth System Analysis Data Assimilation System, NASA
    PI
    01/10/2020 Towards Full Utilization of Satellite Sea Surface Salinity for El Niño/Southern Oscillation Prediction, NASA
    Co-I
    03/11/2021 Evaluating the tropical Pacific Ocean observing system using ECCO and GMAO systems: impacts on seasonal prediction, NASA
    Co-I
    03/11/2021 Developing Coupled Data Assimilation for Integrated Earth System Analysis with GEOS, NASA
    Co-I
    03/11/2021 Development of a well calibrated ocean at multiple spatial scales within the GMAO Integrated Earth System Analysis, NASA
    Co-I
    09/01/2022 Assessing and Improving the Realism of MOM6 Simulations at Time Scales from Hours to Years, NOAA
    Co-I

    Selected Public Outreach

    OceanPredict Coupled Task Team 2021 - Present
    https://oceanpredict.org/teams/task-teams/
    • Co-chair 2021- present
    • Member 2013- present
    OceanPredict Data Assimilation Task Team 2017 - Present
    https://oceanpredict.org/science/task-team-activities/data-assimilation/#section-introduction
    • Member 2017- present
    US CLIVAR AMOC Task Team 2021 - Present
    https://usclivar.org/amoc/task-team-2-amoc-state-variability-and-change
    • Member 2021- present
    ForeSea - Steering Committee 2021 - Present
    https://oceanpredict.org/foresea/foresea-steering-committee/

    A UN Decade of Ocean Science for Sustainable Development project

    Brief Bio

    Dr. Akella works at the Global Modeling and Assimilation Office (GMAO). His research focuses on the development, testing and operational integration of the next generation atmosphere-ocean coupled, Integrated Earth Analysis System (IESA), with emphasis on the ocean and ocean-atmosphere coupling.

    Publications

    Refereed

    Luo, B., P. J. Minnett, M. Szczodrak, and S. Akella. 2022. "Regional and Seasonal Variability of the Oceanic Thermal Skin Effect." Journal of Geophysical Research: Oceans 127 (5): [10.1029/2022jc018465]

    Luo, B., P. J. Minnett, P. Zuidema, N. R. Nalli, and S. Akella. 2021. "Saharan dust effects on North Atlantic sea‐surface skin temperatures." Journal of Geophysical Research: Oceans [10.1029/2021jc017282]

    Gentemann, C. L., J. P. Scott, P. L. Mazzini, et al. C. Pianca, S. Akella, P. J. Minnett, P. Cornillon, B. Fox-Kemper, I. Cetinić, T. M. Chin, J. Gomez-Valdes, J. Vazquez-Cuervo, V. Tsontos, L. Yu, R. Jenkins, S. De Halleux, D. Peacock, and N. Cohen. 2020. "Saildrone: adaptively sampling the marine environment." Bulletin of the American Meteorological Society 101 (6): E744–E762 [10.1175/bams-d-19-0015.1]

    Penny, S. G., S. Akella, M. A. Balmaseda, et al. P. Browne, J. A. Carton, M. Chevallier, F. Counillon, C. Domingues, S. Frolov, P. Heimbach, P. Hogan, I. Hoteit, D. Iovino, P. Laloyaux, M. J. Martin, S. Masina, A. M. Moore, P. de Rosnay, D. Schepers, B. M. Sloyan, A. Storto, A. Subramanian, S. Nam, F. Vitart, C. Yang, Y. Fujii, H. Zuo, T. O’Kane, P. Sandery, T. Moore, and C. C. Chapman. 2019. "Observational Needs for Improving Ocean and Coupled Reanalysis, S2S Prediction, and Decadal Prediction." Frontiers in Marine Science 6 [10.3389/fmars.2019.00391]

    Moore, A. M., M. J. Martin, S. Akella, et al. H. G. Arango, M. Balmaseda, L. Bertino, S. Ciavatta, B. Cornuelle, J. Cummings, S. Frolov, P. Lermusiaux, P. Oddo, P. R. Oke, A. Storto, A. Teruzzi, A. Vidard, and A. T. Weaver. 2019. "Synthesis of Ocean Observations Using Data Assimilation for Operational, Real-Time and Reanalysis Systems: A More Complete Picture of the State of the Ocean." Frontiers in Marine Science 6 [10.3389/fmars.2019.00090]

    Gentemann, C. L., and S. Akella. 2018. "Evaluation of NASA GEOS-ADAS Modeled Diurnal Warming Through Comparisons to SEVIRI and AMSR2 SST Observations." Journal of Geophysical Research: Oceans [10.1002/2017jc013186]

    Gelaro, R., W. McCarty, M. J. Suárez, et al. R. Todling, A. Molod, L. Takacs, C. Randles, A. Darmenov, M. G. Bosilovich, R. Reichle, K. Wargan, L. Coy, R. Cullather, C. Draper, S. Akella, V. Buchard, A. Conaty, A. da Silva, W. Gu, G.-K. Kim, R. Koster, R. Lucchesi, D. Merkova, J. E. Nielsen, G. Partyka, S. Pawson, W. Putman, M. Rienecker, S. D. Schubert, M. Sienkiewicz, and B. Zhao. 2017. "The Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2)." Journal of Climate 30 5419–5454 [10.1175/jcli-d-16-0758.1]

    Akella, S., R. Todling, and M. J. Suarez. 2017. "Assimilation for skin SST in the NASA GEOS atmospheric data assimilation system." Quarterly Journal of the Royal Meteorological Society 143 (703): 1032-1046 [10.1002/qj.2988]

    Brassington, G., M. Martin, H. Tolman, et al. S. Akella, M. Balmeseda, C. Chambers, E. Chassignet, J. Cummings, Y. Drillet, P. Jansen, P. Laloyaux, D. Lea, A. Mehra, I. Mirouze, H. Ritchie, G. Samson, P. Sandery, G. Smith, M. Suarez, and R. Todling. 2015. "Progress and challenges in short- to medium-range coupled prediction." Journal of Operational Oceanography 8 (sup2): s239-s258 [10.1080/1755876x.2015.1049875]

    Vernieres, G. R., R. M. Kovach, C. L. Keppenne, et al. S. R. Akella, L. Brucker, and E. P. Dinnat. 2014. "The impact of the assimilation of Aquarius sea surface salinity data in the GEOS ocean data assimilation system." J. Geophys. Res. Oceans 119 (10): 6974-6987 [10.1002/2014JC010006]

    Akella, S. R. 2011. "Reservoir Multiscale Data Assimilation Using the Ensemble Kalman Filter." Applied Mathematics 02 (02): 165-180 [10.4236/am.2011.22019]

    Chen, X., S. Akella, and I. M. Navon. 2011. "A dual-weighted trust-region adaptive POD 4-D Var applied to a finite-volume shallow water equations model on the sphere." International Journal for Numerical Methods in Fluids 68 (3): 377-402 [10.1002/fld.2523]

    Akella, S., A. Datta-Gupta, and Y. Efendiev. 2011. "ASSIMILATION OF COARSE-SCALEDATAUSINGTHE ENSEMBLE KALMAN FILTER." International Journal for Uncertainty Quantification 1 (1): 49-76 [10.1615/int.j.uncertaintyquantification.v1.i1.40]

    Akella, S., and I. M. Navon. 2008. "Different approaches to model error formulation in 4D-Var: a study with high-resolution advection schemes." Tellus A 61 (1): 112-128 [10.1111/j.1600-0870.2008.00362.x]

    Akella, S., and I. M. Navon. 2005. "A comparative study of the performance of high resolution advection schemes in the context of data assimilation." International Journal for Numerical Methods in Fluids 51 (7): 719-748 [10.1002/fld.1145]

    Mandal, N., and S. R. Akella. 2000. "A Finite Difference Model for Prediction of Welding Thermal History (Part 1)." Journal of the Mechanical Behavior of Materials 11 (5): [10.1515/jmbm.2000.11.5.381]

    Non-Refereed

    Akella, S., and M. J. Suarez. 2018. "The Atmosphere-Ocean Interface Layer of NASA’s Goddard Earth Observing System Model and Data Assimilation System." NASA Technical Report Series on Global Modeling and Data Assimilation, NASA/TM-2018-104606 51 42pp. [Full Text (Link)]

    Kim, J. G., S. R. Akella, A. M. Da Silva, R. Todling, and W. R. Mccarty. 2018. "Preliminary evaluation of influence of aerosols on the simulation of brightness temperature in the NASA’s Goddard Earth Observing System Atmospheric Data Assimilation System." NASA Technical Report Series on Global Modeling and Data Assimilation, NASA/TM-2018-104606 49 44pp [Full Text (Link)]

    Akella, S. R., R. Todling, and M. J. Suarez. 2016. "Estimation of the Ocean Skin Temperature using the NASA GEOS Atmospheric Data Assimilation System." NASA Technical Report Series on Global Modeling and Data Assimilation, NASA/TM-2016-10460 44 88pp

    Bosilovich, M. G., S. R. Akella, L. Coy, et al. R. I. Cullather, C. S. Draper, R. Gelaro, R. M. Kovach, Q. Liu, A. M. Molod, P. M. Norris, K. Wargan, C. Yang, R. H. Reichle, L. L. Takacs, Y. V. Vikhliaev, S. C. Bloom, A. Collow, S. Firth, G. J. Labow, G. S. Partyka, S. Pawson, O. Reale, S. D. Schubert, and M. J. Suarez. 2015. "MERRA-2: Initial Evaluation of the Climate." NASA Technical Report Series on Global Modeling and Data Assimilation 43 (NASA/TM–2015–10) 139 pp.

                                                                                                                                                                                            
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    • Last Updated: 05/30/2023