Ricardo Todling

Ricardo Todling

  • (AST, METEOROLOGICAL STUDIES)
  • 301.614.6171
  • NASA/GSFC
  • Mail Code: 610.1
  • Greenbelt , MD 20771
  • Employer: NASA
  • Brief Bio

    Dr. Ricardo Todling works for the NASA Global Modeling and Assimilation Office (GMAO; former Data Assimilation Office, DAO). He started at NASA/DAO under a National Research Council fellowship in 1992, followed by a fellowship from the Universities Space Research Association in 1994, and subsequently joined Science Applications International Corporation as a contractor working for NASA's DAO and GMAO. In 2009, Dr. Todling was hired as a civil servant working for NASA/GMAO as Research Meteorologist.

    Since 1996, Dr. Todling has been directly involved in develpoments associated with the DAO and GMAO data assimilation systems. He is one of the primany developers of the first NASA/DAO near-real-time data assimilation system built to support NASA's Earth Observing System program in the late 1990's and beyond. Since then, he has been in the role of Leading the data assimilation development in the Goddard Earth Observing System. This system provides data for NASA Instrument Teams to validate and calibrate their products as well as supports Modern-Era Retrospective analysis for Research and Applications efforts. Dr. Todling has served as liaison between GMAO and NOAA's National Centers for Environmental Prediction since the initial days of GMAO. He has directly contributed to the development of the Gridpoint Statistical Interpolation analysis system; this is the system supporting data assimilation efforts at GMAO, NCEP and their Joint Center for Satellite Data Assimilation partners. More recently, Dr. Todling has led the development and implementation of the GMAO Hybrid four-dimensional Ensemble-Variational Data Assimilation System. Dr. Todling is the main developer of the GMAO adjoint-based tool for assessing observation impact to forecasts, and he is now extending the tool to make use of the ensemble of forecasts available from the hybrid data assimilation system.

    Positions/Employment

    2009 - Present

    Research Meteorologist

    National Aeronautics and Space Administration, Goddard Space Flight Center
    1996 - 2009

    Senior Research Scientist

    Science Applications International Corporation, NASA/Goddard Space Flight Center
    1994 - 1996

    Visiting Research Scientist

    Universities Research Association, NASA/Goddard Space Flight Center
    1992 - 1994

    Post-Doctoral Reseacher

    National Research Council, National Academy of Sciences, NASA/Goddard Space Flight Center

    Teaching Experience

    Foundations of Atmospheric Data Assimilation.  September 22-26, 1997: National Laboratory for Computational Sciences, Rio de Janeiro.


    Estimation Theory and Atmospheric Data Assimilation. Winter 1997, semester course at University of Maryland's Meteorology Department.

    Estimation Theory and Atmospheric Data Assimilation. January 22 to February 2, 1996, Institute for Pure and Applied Mathematics, Rio de Janeiro, Brazil.

    Teaching Assistant, from March to December 1984, at the Mathematics Department at Pontificia Universidade Catolica, Rio de Janeiro, Brazil.
     

    Professional Societies

    American Meteorological Society, 1992 - Present

    Awards

    2014 - American Meteorological Society, Monthly Weather Review: For providing thorough, insightful, and high-quality reviews of manuscripts.

    2013 - NASA Performance Award, Summary Rating of Distinguished for Performance Year 2012-2013.

    2012 - NASA Performance Award, Summary Rating of Distinguished for Performance Year 2011-2012.


    2011 - NASA Performance Award, In recognition and appreciation for a fully successful performance rating for 2009-2010.


    2010 - Group Achievement, NASA, for delivery of the Modern Era Retrospective-analysis for Research and Applications (MERRA), a new meteorological analysis placing NASA's EOS data in a climate context.


    2007 - Outstanding Performance, NASA/SAIC, for extraordinary accomplishment in the rapid development of a 4DVAR data assimilation system that includes advanced extensions of a weak-constraint formulation and built-in adjoint capability.


    2005 - Outstanding Performance, NASA/SAIC, for outstanding work in integrating the GEOS-5 DAS to meet multiple high-priority GMAO objectives.

    2004 - Group Achievement, NASA/SAIC, in recognition of the hard work, dedication, and outstanding teamwork in assembling components for the GEOS-5 DAS, and undertaking the initial tests on an accelerated cycle to transition to operations.


    2003 -  Group Achievement, NASA/SAIC, in recognition of the successful developments, evaluation and operational transition of an improved GEOS-4 analysis system in support of CERES and other GMAO customers. Group award.

    2002 - Outstanding Performance, NASA/SAIC, for the many scientific contributions to several areas of critical development and cutting-edge research, including retrospective data assimilation, analysis error estimation, and forecast bias correction.

    2002 - Group Achievement, NASA/SAIC, for outstanding work on developing the adjoint of the finite-volume GCM and providing invaluable support for adjoint-based scientific applications. Joint award with R. Giering and T. Kaminski.


    2001 - Outstanding Performance, NASA/GSC, for work in developing an MPI version of the GEOS DAS, and for integrating various multi-disciplinary science development paths into the DAO's operational system. Joint award with L. L. Takacs.

    2000 - Outstanding Performance, NASA/GSC, for scientific achievement in developing and implementing a moisture bias correction procedure in the NASA/GEOS Terra data assimilation system. Joint award with D. P. Dee.

    1998 - Outstanding Performance, NASA/Goddard Space Flight Center, for system engineering and integration in the migration of GEOS data assimilation system to the Origin 2000 platforms.


    1997 -  Outstanding Performance, NASA/GSC, for leadership during the first migration of GEOS DAS to parallel computing architecture, as a crucial step toward the DAO's operational support of EOS AM1.


    1994 - Outstanding Performance, NASA/Universities Space Research Association, for developing and testing advanced data assimilation schemes.


    1991 - Outstanding Performance, Associated Students UCLA, in recognition of exceptional achievement as a student employee.

    Grants

    10/01/2009 - 09/30/2013 Exploring Model Error Formulations in the GEOS Weak-Constraint 4DVAR., NASA
    PI
    10/01/2010 - 09/30/2015 A Next--generation Integrated Earth System Analysis Coupling between the Ocean and Atmosphere., NASA
    Co-I, turned PI.

    Publications

    Refereed

    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]

    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]

    Takacs, L. L., M. J. Suarez, and R. Todling. 2016. "Maintaining atmospheric mass and water balance in reanalyses." Quarterly Journal of the Royal Meteorological Society, 142: 1565-1573 (In Press) [DOI: 10.1002/qj.2763]

    Todling, R. 2015. "A complementary note to ‘A lag-1 smoother approach to system-error estimation’: the intrinsic limitations of residual diagnostics." Q.J.R. Meteorol. Soc., 141 (692): 2917-2922 [10.1002/qj.2546]

    Todling, R. 2015. "A lag-1 smoother approach to system-error estimation: sequential method." Q.J.R. Meteorol. Soc., 141 (690): 1502-1513 [10.1002/qj.2460]

    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]

    Todling, R. 2013. "Comparing Two Approaches for Assessing Observation Impact." Mon. Weather Rev., 141 (5): 1484-1505 [10.1175/MWR-D-12-00100.1]

    El Akkraoui, A., Y. Tremolet, and R. Todling. 2013. "Preconditioning of variational data assimilation and the use of a bi-conjugate gradient method." Q.J.R. Meteorol. Soc., 139 (672): 731-741 [10.1002/qj.1997]

    Errico, R. M., R. Yang, N. C. Prive, et al. K.-S. Tai, R. Todling, M. E. Sienkiewicz, and J. Guo. 2013. "Development and validation of observing-system simulation experiments at NASA's Global Modeling and Assimilation Office." Q.J.R. Meteorol. Soc., 139 (674): 1162-1178 [10.1002/qj.2027]

    Rienecker, M. M., M. J. Suarez, R. Gelaro, et al. R. Todling, J. Bacmeister, E. Liu, M. G. Bosilovich, S. D. Schubert, L. Takacs, G.-K. Kim, S. Bloom, J. Chen, D. Collins, A. Conaty, A. da Silva, W. Gu, J. Joiner, R. D. Koster, R. Lucchesi, A. Molod, T. Owens, S. Pawson, P. Pegion, C. R. Redder, R. H. Reichle, F. R. Robertson, A. G. Ruddick, M. Sienkiewicz, and J. Woollen. 2011. "MERRA: NASA’s Modern-Era Retrospective Analysis for Research and Applications." J. Climate, 24 (14): 3624-3648 [10.1175/JCLI-D-11-00015.1]

    Gelaro, R., R. H. Langland, S. Pellerin, and R. Todling. 2010. "The THORPEX Observation Impact Intercomparison Experiment." Mon. Wea. Rev., 138 (11): 4009-4025 [10.1175/2010MWR3393.1]

    Daescu, D. N., and R. Todling. 2009. "Adjoint Estimation of the Variation in Model Functional Output due to the Assimilation of Data." Mon. Weather Rev., 137 (5): 1705-1716 [10.1175/2008MWR2659.1]

    Errico, R. M., R. Gelaro, E. Novakovskaia, and R. Todling. 2007. "General characteristics of stratospheric singular vectors." Meteorol. Z., 16 (6): 621-634 [10.1127/0941-2948/2007/0245]

    Stajner, I., C. Benson, H.-C. Liu, et al. S. Pawson, N. Brubaker, L.-P. Chang, L. P. Riishojgaard, and R. Todling. 2007. "Ice polar stratospheric clouds detected from assimilation of Atmospheric Infrared Sounder data." Geophys. Res. Lett, 34 (16): L16802 [10.1029/2007GL029415]

    Bosilovich, M. G., J. Radakovich, A. M. Da Silva, R. Todling, and F. Verter. 2007. "Skin Temperature Analysis and Bias Correction in a Coupled Land-Atmosphere Data Assimilation System." Journal of the Meteorological Society of Japan, 85A:

    Le Marshall, J., J. Jung, J. Derber, et al. R. Treadon, S. J. Lord, M. Goldberg, W. Wolf, H. C. Liu, J. Joiner, J. Woollen, R. Todling, and R. Gelaro. 2005. "Impact of atmospheric infrared sounder observations on weather forecasts." Eos, Transactions American Geophysical Union, 86 (11): 109-116 [10.1029/2005EO110002]

    LeMarshall, J., J. Jung, J. Derber, et al. R. Treadon, S. Lord, M. Goldberg, W. Wolf, H. Liu, J. Joiner, J. Woollen, R. Todling, P. van Delst, and Y. Tahara. 2005. "AIRS hyperspectral data improves southern hemisphere forecasts." Austral Met Mag, 54: 57-60.

    LeMarshall, J., J. Jung, J. Derber, et al. R. Treadon, S. Lord, M. Goldberg, W. Wolf, H. Liu, J. Joiner, J. Woollen, R. Todling, and R. Gelaro. 2005. "Impact of atmospheric infrared sounder observations on weather forecasts." Eos, 86: 109-116.

    Zhu, Y., R. Todling, J. Guo, et al. S. E. Cohn, I. M. Navon, and Y. Yang. 2003. "The GEOS-3 Retrospective Data Assimilation System: The 6-Hour Lag Case." Mon. Weather Rev., 131 (9): 2129-2150 [10.1175/1520-0493(2003)131<2129:TGRDAS>2.0.CO;2]

    Dee, D. P., L. Rukhovets, R. Todling, A. M. da Silva, and J. W. Larson. 2001. "An adaptive buddy check for observational quality control." Quarterly Journal of the Royal Meteorological Society, 127 (577): 2451-2471 [10.1002/qj.49712757714]

    Tippett, M. K., S. E. Cohn, R. Todling, and D. Marchesin. 2000. "Conditioning of the Stable, Discrete-Time Lyapunov Operator." SIAM. J. Matrix Anal. & Appl., 22 (1): 56-65 [10.1137/S0895479899354822]

    Tippett, M. K., S. E. Cohn, R. Todling, and D. Marchesin. 2000. "Low-dimensional representation of error covariance." Tellus, 52A (5): 533-553.

    Dee, P. D., and R. Todling. 2000. "Data Assimilation in the Presence of Forecast Bias: The GEOS Moisture Analysis." Monthly Weather Review, 128 (9): 3268-3282 [http://dx.doi.org/10.1175/1520-0493(2000)128<3268:]

    Todling, R., S. E. Cohn, and N. S. Sivakumaran. 1998. "Suboptimal Schemes for Retrospective Data Assimilation Based on the Fixed-Lag Kalman Smoother." Monthly Weather Review, 126 (8): 2274-2286 [http://dx.doi.org/10.1175/1520-0493(1998)126<2274:]

    Cohn, S. E., and R. Todling. 1996. "Approximate data assimilation schemes for stable and unstable dynamics." JOURNAL-METEOROLOGICAL SOCIETY OF JAPAN SERIES 2, 74: 63--75.

    Ghil, M., and R. Todling. 1996. "Tracking Atmospheric Instabilities with the Kalman Filter. Part II: Two-Layer Results." Monthly Weather Review, 124 (10): 2340-2352 [http://dx.doi.org/10.1175/1520-0493(1996)124<2340:]

    Todling, R., and M. Ghil. 1994. "Tracking Atmospheric Instabilities with the Kalman Filter. Part 1: Methodology and One-Layer Resultst." Monthly Weather Review, 122 (1): 183-204 [http://dx.doi.org/10.1175/1520-0493(1994)122<0183:]

    Cohn, S. E., N. S. Sivakumaran, and R. Todling. 1994. "A fixed-lag Kalman smoother for retrospective data assimilation." Monthly Weather Review, 122 (12): 2838-2867 [http://dx.doi.org/10.1175/1520-0493(1994)122<2838:]

    Todling, R., and S. E. Cohn. 1994. "Suboptimal Schemes for Atmospheric Data Assimilation Based on the Kalman Filter." Monthly Weather Review, 122 (11): 2530-2557 [http://dx.doi.org/10.1175/1520-0493(1994)122<2530:]

    Non-Refereed

    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 Syste." NASA Technical Report Series on Global Modeling and Data Assimilation, NASA/TM-2018-104606 49: 44pp.

    Todling, R., and A. El Akkraoui. 2018. "The GMAO Hybrid Ensemble-Variational Atmospheric Data Assimilation System: Version 2.0." NASA/TM-2018-104606 50: 184pp [https://gmao.gsfc.nasa.gov/pubs/docs/Todling1019.p]

    Errico, R. M., N. C. Prive, D. Carvalho, et al. A. El Akkraoui, J. Guo, R. Todling, W. R. Mccarty, W. M. Putman, A. M. Da Silva, R. Gelaro, and I. Moradi. 2017. "Description of the GMAO OSSE for Weather Analysis Software Package: Version 3." NASA TM-2017-104606 48: 156pp [https://gmao.gsfc.nasa.gov/pubs/docs/Errico987.pdf]

    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.

    Takacs, L. L., M. J. Suarez, and R. Todling. 2015. "Maintaining Atmospheric Mass and Water Balance Within Reanalysis." NASA TM-–2014-104606 37: 39pp [https://gmao.gsfc.nasa.gov/pubs/docs/Takacs737.pdf]

    Yang, W., I. M. Navon, and R. Todling. 1997. "Documentation of the Tangent Linear and Adjoint Models of the Relaxed Arakawa-Schubert Moisture Parameterization Package of the NASA GEOS-1 GCM (Version 5.2)." NASA/Tech. Memo. 104606 11: 40 [https://gmao.gsfc.nasa.gov/pubs/docs/Yang131.pdf]

    Brief Bio

    Dr. Ricardo Todling works for the NASA Global Modeling and Assimilation Office (GMAO; former Data Assimilation Office, DAO). He started at NASA/DAO under a National Research Council fellowship in 1992, followed by a fellowship from the Universities Space Research Association in 1994, and subsequently joined Science Applications International Corporation as a contractor working for NASA's DAO and GMAO. In 2009, Dr. Todling was hired as a civil servant working for NASA/GMAO as Research Meteorologist.

    Since 1996, Dr. Todling has been directly involved in develpoments associated with the DAO and GMAO data assimilation systems. He is one of the primany developers of the first NASA/DAO near-real-time data assimilation system built to support NASA's Earth Observing System program in the late 1990's and beyond. Since then, he has been in the role of Leading the data assimilation development in the Goddard Earth Observing System. This system provides data for NASA Instrument Teams to validate and calibrate their products as well as supports Modern-Era Retrospective analysis for Research and Applications efforts. Dr. Todling has served as liaison between GMAO and NOAA's National Centers for Environmental Prediction since the initial days of GMAO. He has directly contributed to the development of the Gridpoint Statistical Interpolation analysis system; this is the system supporting data assimilation efforts at GMAO, NCEP and their Joint Center for Satellite Data Assimilation partners. More recently, Dr. Todling has led the development and implementation of the GMAO Hybrid four-dimensional Ensemble-Variational Data Assimilation System. Dr. Todling is the main developer of the GMAO adjoint-based tool for assessing observation impact to forecasts, and he is now extending the tool to make use of the ensemble of forecasts available from the hybrid data assimilation system.

    Publications

    Refereed

    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]

    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]

    Takacs, L. L., M. J. Suarez, and R. Todling. 2016. "Maintaining atmospheric mass and water balance in reanalyses." Quarterly Journal of the Royal Meteorological Society (In Press) 142 1565-1573 [DOI: 10.1002/qj.2763]

    Todling, R. 2015. "A complementary note to ‘A lag-1 smoother approach to system-error estimation’: the intrinsic limitations of residual diagnostics." Q.J.R. Meteorol. Soc. 141 (692): 2917-2922 [10.1002/qj.2546]

    Todling, R. 2015. "A lag-1 smoother approach to system-error estimation: sequential method." Q.J.R. Meteorol. Soc. 141 (690): 1502-1513 [10.1002/qj.2460]

    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]

    Todling, R. 2013. "Comparing Two Approaches for Assessing Observation Impact." Mon. Weather Rev. 141 (5): 1484-1505 [10.1175/MWR-D-12-00100.1]

    El Akkraoui, A., Y. Tremolet, and R. Todling. 2013. "Preconditioning of variational data assimilation and the use of a bi-conjugate gradient method." Q.J.R. Meteorol. Soc. 139 (672): 731-741 [10.1002/qj.1997]

    Errico, R. M., R. Yang, N. C. Prive, et al. K.-S. Tai, R. Todling, M. E. Sienkiewicz, and J. Guo. 2013. "Development and validation of observing-system simulation experiments at NASA's Global Modeling and Assimilation Office." Q.J.R. Meteorol. Soc. 139 (674): 1162-1178 [10.1002/qj.2027]

    Rienecker, M. M., M. J. Suarez, R. Gelaro, et al. R. Todling, J. Bacmeister, E. Liu, M. G. Bosilovich, S. D. Schubert, L. Takacs, G.-K. Kim, S. Bloom, J. Chen, D. Collins, A. Conaty, A. da Silva, W. Gu, J. Joiner, R. D. Koster, R. Lucchesi, A. Molod, T. Owens, S. Pawson, P. Pegion, C. R. Redder, R. H. Reichle, F. R. Robertson, A. G. Ruddick, M. Sienkiewicz, and J. Woollen. 2011. "MERRA: NASA’s Modern-Era Retrospective Analysis for Research and Applications." J. Climate 24 (14): 3624-3648 [10.1175/JCLI-D-11-00015.1]

    Gelaro, R., R. H. Langland, S. Pellerin, and R. Todling. 2010. "The THORPEX Observation Impact Intercomparison Experiment." Mon. Wea. Rev. 138 (11): 4009-4025 [10.1175/2010MWR3393.1]

    Daescu, D. N., and R. Todling. 2009. "Adjoint Estimation of the Variation in Model Functional Output due to the Assimilation of Data." Mon. Weather Rev. 137 (5): 1705-1716 [10.1175/2008MWR2659.1]

    Errico, R. M., R. Gelaro, E. Novakovskaia, and R. Todling. 2007. "General characteristics of stratospheric singular vectors." Meteorol. Z. 16 (6): 621-634 [10.1127/0941-2948/2007/0245]

    Stajner, I., C. Benson, H.-C. Liu, et al. S. Pawson, N. Brubaker, L.-P. Chang, L. P. Riishojgaard, and R. Todling. 2007. "Ice polar stratospheric clouds detected from assimilation of Atmospheric Infrared Sounder data." Geophys. Res. Lett 34 (16): L16802 [10.1029/2007GL029415]

    Bosilovich, M. G., J. Radakovich, A. M. Da Silva, R. Todling, and F. Verter. 2007. "Skin Temperature Analysis and Bias Correction in a Coupled Land-Atmosphere Data Assimilation System." Journal of the Meteorological Society of Japan 85A

    Le Marshall, J., J. Jung, J. Derber, et al. R. Treadon, S. J. Lord, M. Goldberg, W. Wolf, H. C. Liu, J. Joiner, J. Woollen, R. Todling, and R. Gelaro. 2005. "Impact of atmospheric infrared sounder observations on weather forecasts." Eos, Transactions American Geophysical Union 86 (11): 109-116 [10.1029/2005EO110002]

    LeMarshall, J., J. Jung, J. Derber, et al. R. Treadon, S. Lord, M. Goldberg, W. Wolf, H. Liu, J. Joiner, J. Woollen, R. Todling, P. van Delst, and Y. Tahara. 2005. "AIRS hyperspectral data improves southern hemisphere forecasts." Austral Met Mag 54 57-60

    LeMarshall, J., J. Jung, J. Derber, et al. R. Treadon, S. Lord, M. Goldberg, W. Wolf, H. Liu, J. Joiner, J. Woollen, R. Todling, and R. Gelaro. 2005. "Impact of atmospheric infrared sounder observations on weather forecasts." Eos 86 109-116

    Zhu, Y., R. Todling, J. Guo, et al. S. E. Cohn, I. M. Navon, and Y. Yang. 2003. "The GEOS-3 Retrospective Data Assimilation System: The 6-Hour Lag Case." Mon. Weather Rev. 131 (9): 2129-2150 [10.1175/1520-0493(2003)131<2129:TGRDAS>2.0.CO;2]

    Dee, D. P., L. Rukhovets, R. Todling, A. M. da Silva, and J. W. Larson. 2001. "An adaptive buddy check for observational quality control." Quarterly Journal of the Royal Meteorological Society 127 (577): 2451-2471 [10.1002/qj.49712757714]

    Tippett, M. K., S. E. Cohn, R. Todling, and D. Marchesin. 2000. "Conditioning of the Stable, Discrete-Time Lyapunov Operator." SIAM. J. Matrix Anal. & Appl. 22 (1): 56-65 [10.1137/S0895479899354822]

    Tippett, M. K., S. E. Cohn, R. Todling, and D. Marchesin. 2000. "Low-dimensional representation of error covariance." Tellus 52A (5): 533-553

    Dee, P. D., and R. Todling. 2000. "Data Assimilation in the Presence of Forecast Bias: The GEOS Moisture Analysis." Monthly Weather Review 128 (9): 3268-3282 [http://dx.doi.org/10.1175/1520-0493(2000)128<3268:]

    Todling, R., S. E. Cohn, and N. S. Sivakumaran. 1998. "Suboptimal Schemes for Retrospective Data Assimilation Based on the Fixed-Lag Kalman Smoother." Monthly Weather Review 126 (8): 2274-2286 [http://dx.doi.org/10.1175/1520-0493(1998)126<2274:]

    Cohn, S. E., and R. Todling. 1996. "Approximate data assimilation schemes for stable and unstable dynamics." JOURNAL-METEOROLOGICAL SOCIETY OF JAPAN SERIES 2 74 63--75

    Ghil, M., and R. Todling. 1996. "Tracking Atmospheric Instabilities with the Kalman Filter. Part II: Two-Layer Results." Monthly Weather Review 124 (10): 2340-2352 [http://dx.doi.org/10.1175/1520-0493(1996)124<2340:]

    Todling, R., and M. Ghil. 1994. "Tracking Atmospheric Instabilities with the Kalman Filter. Part 1: Methodology and One-Layer Resultst." Monthly Weather Review 122 (1): 183-204 [http://dx.doi.org/10.1175/1520-0493(1994)122<0183:]

    Cohn, S. E., N. S. Sivakumaran, and R. Todling. 1994. "A fixed-lag Kalman smoother for retrospective data assimilation." Monthly Weather Review 122 (12): 2838-2867 [http://dx.doi.org/10.1175/1520-0493(1994)122<2838:]

    Todling, R., and S. E. Cohn. 1994. "Suboptimal Schemes for Atmospheric Data Assimilation Based on the Kalman Filter." Monthly Weather Review 122 (11): 2530-2557 [http://dx.doi.org/10.1175/1520-0493(1994)122<2530:]

    Non-Refereed

    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 Syste." NASA Technical Report Series on Global Modeling and Data Assimilation, NASA/TM-2018-104606 49 44pp

    Todling, R., and A. El Akkraoui. 2018. "The GMAO Hybrid Ensemble-Variational Atmospheric Data Assimilation System: Version 2.0." NASA/TM-2018-104606 50 184pp [https://gmao.gsfc.nasa.gov/pubs/docs/Todling1019.p]

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