Data Assimilation for Earth System Science, Atmospheric Dynamics and Stochastics, Numerical Weather Prediction, Estimation Theory, Partial Differential Equations
1991
-
Present
Research Meteorologist, Computer Scientist, Mathematician
NASA Goddard Space Flight Center,
Greenbelt, Maryland
1991
-
1991
Research Scientist
Universities Space Research Association,
Greenbelt, Maryland
1990
-
1991
UCAR Senior Fellow
National Meteorological Center,
Camp Springs, Maryland
1988
-
1988
Visiting Professor
Universidade Federal do Rio de Janeiro,
Rio de Janeiro, Brazil
1987
-
1987
Visiting Professor
Universita di Catania,
Catania, Italy
1983
-
1985
Visiting Professor
Pontificia Universidade Catolica do Rio de Janeiro,
Rio de Janeiro, Brazil
1982
-
1991
Assistant Research Scientist through Research Assistant Professor
Courant Institute of Mathematical Sciences, New York University,
New York, New York
Ph.D., Mathematics, Courant Institute of Mathematical Sciences, New York University, 1982. Thesis Title: Methods of Sequential Estimation for Determining Initial Data in Numerical Weather Prediction
M.S., Mathematics, Courant Institute of Mathematical Sciences, New York University, 1978
B.S., Physics and Mathematics, Drexel University, 1976
American Meteorological Society,
1978
-
Present
American Mathematical Society,
1976
-
Present
Society for Industrial and Applied Mathematics,
1976
-
Present
2016 - 2021: Assistant Chief, Global Modeling and Assimilation Office
2014 - 2021: Member, GMAO Strategic Management Team
2008 - 2009: Member, International Scientific Organizing Committee, Fifth WMO International Symposium on Data Assimilation, Melbourne, Australia
2005: Guest Editor, Quarterly Journal of the Royal Meteorological Society
2004 - 2005: Co-Chair, International Program Committee, Fourth WMO International Symposium on Assimilation of Observations in Meteorology and Oceanography, Prague, Czech Republic
2003 - 2008: Editor, Monthly Weather Review
2002 - 2003: Member, Scientific Committee, Roger Daley Memorial Symposium, Montreal, Canada
2002: Lecturer, NATO Advanced Study Institute (ASI) on Data Assimilation for the Earth System, Maratea, Italy
2000 - 2002: Chief Scientist for Analysis, Data Assimilation Office, GSFC
2000 - 2001: Ph.D. Thesis Supervisor (Tijana Janjic), University of Maryland College Park
2000 - 2001: Special Faculty, University of Maryland College Park
1998 - 2000: Associate Editor, Monthly Weather Review
1995: Member, Scientific Committee, Second UNAM-Cray Supercomputing Conference on Numerical Simulations in the Environmental and Earth Sciences, Mexico City, Mexico
1993 - 1998: Lead Scientist for GEOS Data Assimilation System Development, GSFC
1993 - 1995: Fellow, Joint Center for Earth System Science
1992, 2002: Branch Representative, Summer Institute on Atmospheric and Hydrospheric Sciences
1992 - 1998: Chair, GSFC Library Committee
1992 - 1994: Chair and Founding Member, Goddard Mathematics Group
As of October 2022:
Total Citations: 5,190
Total Publications: 108
H-Index: 25
I10-Index: 35
2020 - 2021: Lead, PDT, SAMDA II Contract
2017 - 2021: Alt-COR, SAMDA Contract
2016: COR, Remote Sensing Systems (RSS) Contract
2015 - 2016: Member, PDT, Support for Atmospheres, Modeling and Data Assimilation (SAMDA) Contract
2012 - 2013: Member, SEB, Information Sciences and Library Services (ISLS) Contract
2011 - 2012: Member, SEB, Support for Atmospheric Sciences (SAS) Contract
2011: Member, SEB, Global Modeling and Assimilation Office (GMAO) Contract
2006 - 2017: COTR, Global Modeling and Assimilation Office (GMAO) Contract
2005: Chair, SEB, Global Modeling and Assimilation Office (GMAO) Contract
2000: Member, SEB, Laboratory for Atmospheres (LAS) Contract
Refereed
Wargan, K., B. Weir, G. L. Manney, et al. 2023. "M2‐SCREAM: A Stratospheric Composition Reanalysis of Aura MLS Data With MERRA‐2 Transport."
Earth and Space Science,
10
(2):
e2022EA002632
[10.1029/2022ea002632]
Gilpin, S., T. Matsuo, and S. E. Cohn. 2022. "Continuum Covariance Propagation for Understanding Variance Loss in Advective Systems."
SIAM/ASA Journal on Uncertainty Quantification,
10
(3):
886-914
[10.1137/21m1442449]
Malings, C., K. E. Knowland, C. A. Keller, and S. E. Cohn. 2021. "Sub‐City Scale Hourly Air Quality Forecasting by Combining Models, Satellite Observations, and Ground Measurements."
Earth and Space Science,
8
(7):
[10.1029/2021ea001743]
Wargan, K., B. Weir, G. L. Manney, S. E. Cohn, and N. J. Livesey. 2020. "The Anomalous 2019 Antarctic Ozone Hole in the GEOS Constituent Data Assimilation System With MLS Observations."
Journal of Geophysical Research: Atmospheres,
125
(18):
[10.1029/2020jd033335]
Janjić, T., N. Bormann, M. Bocquet, et al. 2017. "On the representation error in data assimilation."
Quarterly Journal of the Royal Meteorological Society,
144
(713):
1257-1278
[10.1002/qj.3130]
Janjic, T., D. McLaughlin, S. E. Cohn, and M. Verlaan. 2014. "Conservation of Mass and Preservation of Positivity with Ensemble-Type Kalman Filter Algorithms."
Mon. Wea. Rev.,
142
(2):
755-773
[10.1175/MWR-D-13-00056.1]
Cacio, E., S. E. Cohn, and R. Spigler. 2012. "Numerical treatment of degenerate diffusion equations via Feller's boundary classification, and applications."
Numerical Methods for Partial Differential Equations,
28
(3):
807-833
[10.1002/num.20657]
Cohn, S. E. 2010. "The principle of energetic consistency in data assimilation."
Data Assimilation: Making Sense of Observations,
Chapter 7:
137--216
[10.1007/978-3-540-74703-1]
Cohn, S. E. 2009. "Energetic Consistency and Coupling of the Mean and Covariance Dynamics."
Handbook of Numerical Analysis Vol. XIV, Special Volume: Computational Methods for the Atmosphere and the Oceans,
Chapter 10:
443-478
[10.1016/s1570-8659(08)00210-x]
Janjić, T., and S. E. Cohn. 2006. "Treatment of Observation Error due to Unresolved Scales in Atmospheric Data Assimilation."
Monthly Weather Review,
134
(10):
2900-2915
[10.1175/mwr3229.1]
Gaspari, G., S. E. Cohn, J. Guo, and S. Pawson. 2006. "Construction and application of covariance functions with variable length-fields."
Q.J.R. Meteorol. Soc.,
132
(619):
1815-1838
[10.1256/qj.05.08]
Lyster, P. M., S. E. Cohn, B. Zhang, et al. 2004. "A Lagrangian trajectory filter for constituent data assimilation."
Q. J. R. Meteorol. Soc.,
130
(601):
2315-2334
[10.1256/qj.02.234]
Yang, R., S. Cohn, A. da Silva, J. Joiner, and P. R. Houser. 2003. "Tangent linear analysis of the Mosaic land surface model."
J. Geophys. Res.,
108
(D2):
4054
[10.1029/2002JD002410]
Zhu, Y., R. Todling, J. Guo, et al. 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]
Tippett, M. K., and S. E. Cohn. 2001. "Adjoints and low-rank covariance representation."
Nonlinear Processes in Geophysics,
8
(6):
331-340
[10.5194/npg-8-331-2001]
Tippett, M. K., S. E. Cohn, R. Todling, and D. Marchesin. 2000. "Low-dimensional representation of error covariance."
Tellus,
52A
(5):
533-553.
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]
M'enard, R., S. E. Cohn, L.-P. Chang, and P. M. Lyster. 2000. "Assimilation of stratospheric chemical tracer observations using a Kalman filter. Part I: Formulation."
Monthly Weather Review,
128
(8):
2654--2671.
Gaspari, G., and S. E. Cohn. 1999. "Construction of correlation functions in two and three dimensions."
Quarterly Journal of the Royal Meteorological Society,
125
(554):
723-757
[10.1256/smsqj.55416]
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:]
Li, Y., R. Ménard, L. P. Riishøjgaard, S. E. Cohn, and R. B. Rood. 1998. "A study on assimilating potential vorticity data."
Tellus A,
50
(4):
490-506
[10.1034/j.1600-0870.1998.t01-2-00008.x]
Riishojgaard, L., S. E. Cohn, Y. Li, and R. M'enard. 1998. "The use of spline interpolation in semi-Lagrangian transport models."
Monthly weather review,
126
(7):
2008--2016.
Cohn, S. E., A. Da Silva, J. Guo, M. Sienkiewicz, and D. Lamich. 1998. "Assessing the Effects of Data Selection with the DAO Physical-Space Statistical Analysis System*."
Monthly Weather Review,
126
(11):
2913--2926.
Cohn, S. E. 1997. "An introduction to estimation theory."
JOURNAL-METEOROLOGICAL SOCIETY OF JAPAN SERIES 2,
75:
147--178.
Kalnay, E., D. L. Anderson, A. F. Bennett, et al. 1997. "Data assimilation in the ocean and in the atmosphere: what should be next?"
Journal of the Meteorological Society of Japan,
75
(1B):
489--496.
Lyster, P., S. E. Cohn, R. Menard, et al. 1997. "Parallel implementation of a Kalman filter for constituent data assimilation."
Monthly weather review,
125
(7):
1674--1686.
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.
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:]
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:]
Cohn, S. E. 1993. "Dynamics of short-term univariate forecast error covariances."
Monthly weather review,
121
(11):
3123--3149.
Augenbaum, J., S. E. Cohn, and D. Marchesin. 1991. "Eliminating grid-orientation errors in alternating-direction implicit schemes."
Applied Numerical Mathematics,
8
(1):
1-10
[10.1016/0168-9274(91)90094-g]
Cohn, S. E., and D. F. Parrish. 1991. "The behavior of forecast error covariances for a Kalman filter in two dimensions."
Monthly Weather Review,
119
(8):
1757--1785.
Cohn, S. E., and D. P. Dee. 1989. "An analysis of the vertical structure equation for arbitrary thermal profiles."
Quarterly Journal of the Royal Meteorological Society,
115
(485):
143-171
[10.1002/qj.49711548508]
Cohn, S. E., and D. P. Dee. 1988. "Observability of Discretized Partial Differential Equations."
SIAM Journal on Numerical Analysis,
25
(3):
586-617
[10.1137/0725037]
Dee, D., S. Cohn, A. Dalcher, and M. Ghil. 1985. "An efficient algorithm for estimating noise covariances in distributed systems."
IEEE Transactions on Automatic Control,
30
(11):
1057-1065
[10.1109/tac.1985.1103837]
Augenbaum, J. M., S. E. Cohn, E. Isaacson, D. P. Dee, and D. Marchesin. 1985. "A factored implicit scheme for numerical weather prediction."
Comm. Pure Appl. Math.,
38
(5):
503-517
[10.1002/cpa.3160380504]
Cohn, S. E., D. Dee, D. Marchesin, E. Isaacson, and G. Zwas. 1985. "A fully implicit scheme for the barotropic primitive equations."
Monthly weather review,
113
(4):
436--448.
Refereed
Wargan, K., B. Weir, G. L. Manney, et al. 2023. "M2‐SCREAM: A Stratospheric Composition Reanalysis of Aura MLS Data With MERRA‐2 Transport."
Earth and Space Science
10
(2):
e2022EA002632
[10.1029/2022ea002632]
Gilpin, S., T. Matsuo, and S. E. Cohn. 2022. "Continuum Covariance Propagation for Understanding Variance Loss in Advective Systems."
SIAM/ASA Journal on Uncertainty Quantification
10
(3):
886-914
[10.1137/21m1442449]
Malings, C., K. E. Knowland, C. A. Keller, and S. E. Cohn. 2021. "Sub‐City Scale Hourly Air Quality Forecasting by Combining Models, Satellite Observations, and Ground Measurements."
Earth and Space Science
8
(7):
[10.1029/2021ea001743]
Wargan, K., B. Weir, G. L. Manney, S. E. Cohn, and N. J. Livesey. 2020. "The Anomalous 2019 Antarctic Ozone Hole in the GEOS Constituent Data Assimilation System With MLS Observations."
Journal of Geophysical Research: Atmospheres
125
(18):
[10.1029/2020jd033335]
Janjić, T., N. Bormann, M. Bocquet, et al. 2017. "On the representation error in data assimilation."
Quarterly Journal of the Royal Meteorological Society
144
(713):
1257-1278
[10.1002/qj.3130]
Janjic, T., D. McLaughlin, S. E. Cohn, and M. Verlaan. 2014. "Conservation of Mass and Preservation of Positivity with Ensemble-Type Kalman Filter Algorithms."
Mon. Wea. Rev.
142
(2):
755-773
[10.1175/MWR-D-13-00056.1]
Cacio, E., S. E. Cohn, and R. Spigler. 2012. "Numerical treatment of degenerate diffusion equations via Feller's boundary classification, and applications."
Numerical Methods for Partial Differential Equations
28
(3):
807-833
[10.1002/num.20657]
Cohn, S. E. 2010. "The principle of energetic consistency in data assimilation."
Data Assimilation: Making Sense of Observations
Chapter 7
137--216
[10.1007/978-3-540-74703-1]
Cohn, S. E. 2009. "Energetic Consistency and Coupling of the Mean and Covariance Dynamics."
Handbook of Numerical Analysis Vol. XIV, Special Volume: Computational Methods for the Atmosphere and the Oceans
Chapter 10
443-478
[10.1016/s1570-8659(08)00210-x]
Janjić, T., and S. E. Cohn. 2006. "Treatment of Observation Error due to Unresolved Scales in Atmospheric Data Assimilation."
Monthly Weather Review
134
(10):
2900-2915
[10.1175/mwr3229.1]
Gaspari, G., S. E. Cohn, J. Guo, and S. Pawson. 2006. "Construction and application of covariance functions with variable length-fields."
Q.J.R. Meteorol. Soc.
132
(619):
1815-1838
[10.1256/qj.05.08]
Lyster, P. M., S. E. Cohn, B. Zhang, et al. 2004. "A Lagrangian trajectory filter for constituent data assimilation."
Q. J. R. Meteorol. Soc.
130
(601):
2315-2334
[10.1256/qj.02.234]
Yang, R., S. Cohn, A. da Silva, J. Joiner, and P. R. Houser. 2003. "Tangent linear analysis of the Mosaic land surface model."
J. Geophys. Res.
108
(D2):
4054
[10.1029/2002JD002410]
Zhu, Y., R. Todling, J. Guo, et al. 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]
Tippett, M. K., and S. E. Cohn. 2001. "Adjoints and low-rank covariance representation."
Nonlinear Processes in Geophysics
8
(6):
331-340
[10.5194/npg-8-331-2001]
Tippett, M. K., S. E. Cohn, R. Todling, and D. Marchesin. 2000. "Low-dimensional representation of error covariance."
Tellus
52A
(5):
533-553
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]
M'enard, R., S. E. Cohn, L.-P. Chang, and P. M. Lyster. 2000. "Assimilation of stratospheric chemical tracer observations using a Kalman filter. Part I: Formulation."
Monthly Weather Review
128
(8):
2654--2671
Gaspari, G., and S. E. Cohn. 1999. "Construction of correlation functions in two and three dimensions."
Quarterly Journal of the Royal Meteorological Society
125
(554):
723-757
[10.1256/smsqj.55416]
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:]
Li, Y., R. Ménard, L. P. Riishøjgaard, S. E. Cohn, and R. B. Rood. 1998. "A study on assimilating potential vorticity data."
Tellus A
50
(4):
490-506
[10.1034/j.1600-0870.1998.t01-2-00008.x]
Riishojgaard, L., S. E. Cohn, Y. Li, and R. M'enard. 1998. "The use of spline interpolation in semi-Lagrangian transport models."
Monthly weather review
126
(7):
2008--2016
Cohn, S. E., A. Da Silva, J. Guo, M. Sienkiewicz, and D. Lamich. 1998. "Assessing the Effects of Data Selection with the DAO Physical-Space Statistical Analysis System*."
Monthly Weather Review
126
(11):
2913--2926
Cohn, S. E. 1997. "An introduction to estimation theory."
JOURNAL-METEOROLOGICAL SOCIETY OF JAPAN SERIES 2
75
147--178
Kalnay, E., D. L. Anderson, A. F. Bennett, et al. 1997. "Data assimilation in the ocean and in the atmosphere: what should be next?"
Journal of the Meteorological Society of Japan
75
(1B):
489--496
Lyster, P., S. E. Cohn, R. Menard, et al. 1997. "Parallel implementation of a Kalman filter for constituent data assimilation."
Monthly weather review
125
(7):
1674--1686
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
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:]
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:]
Cohn, S. E. 1993. "Dynamics of short-term univariate forecast error covariances."
Monthly weather review
121
(11):
3123--3149
Augenbaum, J., S. E. Cohn, and D. Marchesin. 1991. "Eliminating grid-orientation errors in alternating-direction implicit schemes."
Applied Numerical Mathematics
8
(1):
1-10
[10.1016/0168-9274(91)90094-g]
Cohn, S. E., and D. F. Parrish. 1991. "The behavior of forecast error covariances for a Kalman filter in two dimensions."
Monthly Weather Review
119
(8):
1757--1785
Cohn, S. E., and D. P. Dee. 1989. "An analysis of the vertical structure equation for arbitrary thermal profiles."
Quarterly Journal of the Royal Meteorological Society
115
(485):
143-171
[10.1002/qj.49711548508]
Cohn, S. E., and D. P. Dee. 1988. "Observability of Discretized Partial Differential Equations."
SIAM Journal on Numerical Analysis
25
(3):
586-617
[10.1137/0725037]
Dee, D., S. Cohn, A. Dalcher, and M. Ghil. 1985. "An efficient algorithm for estimating noise covariances in distributed systems."
IEEE Transactions on Automatic Control
30
(11):
1057-1065
[10.1109/tac.1985.1103837]
Augenbaum, J. M., S. E. Cohn, E. Isaacson, D. P. Dee, and D. Marchesin. 1985. "A factored implicit scheme for numerical weather prediction."
Comm. Pure Appl. Math.
38
(5):
503-517
[10.1002/cpa.3160380504]
Cohn, S. E., D. Dee, D. Marchesin, E. Isaacson, and G. Zwas. 1985. "A fully implicit scheme for the barotropic primitive equations."
Monthly weather review
113
(4):
436--448
