MailStop 610.1,
Global Modeling and Assimilation Office,
Greenbelt,
MD 20771, USA.
Email: Sarith.P.Mahanama@nasa.gov
Goddard Earth Sciences and Technology
Center,
5523 Research Park Drive, Suite 320,
University of Maryland, Baltimore County,
Baltimore,
MD 21250, USA.
Global
Modeling and Assimilation Office at the NASA Goddard Space Flight Center:
Research Interests: The role of the land surface in the climate system - This
includes the development and application of land-surface models, studies of the
impact of land surface variability on the predictability of climate,
interactions between the terrestrial and atmospheric branches of the hydrologic
cycle, and the impacts of land use change on regional and global climate.
Education:
Ph.D 2000 Department of Civil Engineering, The University of Hong Kong,
Hong Kong (SAR).
B.Sc.Eng (Honors) 1993 Department of Civil Engineering, University of Peradeniya,
K-12 (1973-1985)
Dharmaraja
College, Kandy, Sri Lanka.
Research Experience:
2000-present Research Scientist, Global Modeling
and Assimilation Office, NASA Goddard
Space Flight Center, Greenbelt, Maryland, USA contracted with University of Maryland Baltimore County (UMBC) Goddard Earth Sciences and Technology Center
(GEST)
2007-Present Associate Research Scientist, GEST/UMBC
2001-2006 Assistant Research Scientist, GEST/UMBC
2000-2001 Research Associate, GEST/UMBC
1998-2000 Research Assistant, Department
of Civil Engineering, The University of Hong
Kong
Awards and Honours:
2006 The NASA GMAO
Outstanding Performance Award
Professional Affiliations:
American
Geophysical Union, Member
American Meteorological Society, Member
Publications:
Randal Koster, Sarith
Mahanama, Tomohito J. Yamada, Gianpaolo
Balsamo, Marie Boisserie, Paul Dirmeyer,
Francisco Doblas-Reyes, C. T. Gordon, Zhichang Guo, Jee-Hoon
Jeong, David Lawrence, Zhao Li, Lifeng
Luo, Sergey Malyshev, William
Merryfield, Sonia I. Seneviratne,
Tanja Stanelle, Bart van
den Hurk, Frederic Vitart, and
Eric F. Wood (2009): The Contribution of Land Surface Initialization to Subseasonal Forecast Skill: First Results from the GLACE-2 Project, Geophy. Res. Letters, submitted.
Surabi Menon,
Hashem Akbari, Sarith
Mahanama, Igor Sednev and Ronnen
Levinson (2009): Radiative forcing and temperature
response to changes in urban albedos and associated
CO2 offsets, Env. Res. Letters, submitted.
Mahanama, S.P.P., Koster R., Lettenmaier D.P., and R H Reichle (2009), Contribution of Soil Moisture Information
to Streamflow Prediction in the Snowmelt Season: A Continental-Scale Analysis, Geophysical Research Letters, submitted.
Koster R., H. Wang, S.
Schubert, M. Suarez, and S. Mahanama (2009): Drought-Induced Warming in
the Continental United States Under Different SST Regimes, Journal of Climate, Special Issue on US-CLIVAR Drought Working Group
Experiments (Volume 22 Issue 20), 5385–5400. DOI: 10.1175/2009JCLI3075.1.
Aihui Wang, Theodore J. Bohn, Sarith
P. Mahanama, Randal D. Koster, and Dennis P. Lettenmaier (2009): Multimodel ensemble reconstruction of drought over the
continental United States, J. Climate,
(V22 Issue 10), 2694-2722.doi:10.1175/2008JCLI2586.1.
Reichle, R. H., M. G. Bosilovich, W. T. Crow, R. D. Koster, S. V. Kumar, S. P. P. Mahanama, and B. F. Zaitchik (2009): Recent Advances in Land Data Assimilation at the NASA Global Modeling and Assimilation Office, Chapter 21 of Data Assimilation for Atmospheric, Oceanic, and Hydrologic Applications, Seon Ki Park, editor, Springer. DOI: 10.1007/978-3-540-71056-1.
Mahanama, S.P.P., R.D. Koster, R. H. Reichle, and L. Zubair (2008): The role of Soil Moisture Initialization in
Sub—seasonal and Seasonal Streamflow Predictability- a Case Study in Sri Lanka,
Adv Water Resour, 31,
1333–1343, doi:10.1016/j.advwatres.2008.06.004.
Mahanama,
S.P.P., R.D. Koster, R.H. Reichle, and M. J. Suarez (2008): Impact of Subsurface Temperature Variability
on Surface air temperature Variability: An AGCM Study, J. Hydrometeorology, (V9
No4), 804-815, 2008.doi:10.1175/2008JHM949.1
R H Reichle, W T Crow, R D Koster, H O Sharif, and S P P Mahanama
(2007): The contribution of soil moisture retrievals to land data assimilation
products, Geophysical Research Letters,
35, L01404,
doi:10.1029/2007GL031986.
Reichle,
R. H., R. D. Koster, P. Liu, S. P. P.
Mahanama, E. G. Njoku, and M. Owe (2007),
Comparison and assimilation of global soil moisture retrievals from the
Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E)
and the Scanning Multichannel Microwave Radiometer (SMMR), J. Geophys. Res., 112, D09108, doi:10.1029/2006JD008033.
Mahanama,
S.P.P., and R.D. Koster: AGCM biases
in evaporation regime: Impact on soil moisture memory and land-atmosphere
feedback, J. Hydrometeorology, (V6 No5), 656-669, 2005.
Mahanama,
S.P.P., and R.D. Koster:
Intercomparison soil moisture memory in two land surface models, J.
Hydrometeorology, (V4 No6), 1134-1146, 2003.
Gao X., P.A. Dirmeyer, Z. Guo, M. Zhao, B. Decharme, G. Niu, and S. Mahanama,
2006: An approach for remote sensing validation of land surface schemes on a
global scale. J Hydrometeor (in revision).
Guillevic, P.C., R. D. Koster, M. J. Suarez, L. Bounoua, G. J. Collatz, S. O. Los
and S. P. P. Mahanama, Influence of
the interannual variability of vegetation on
hydrological processes over land surfaces,
J. Hydrometeorology, (V3), 617-629, 2002.
Boone, A., F. Habets,
J. Noilhan, D. Clark, P. Dirmeyer,
S. Fox, Y. Gusev, I. Haddeland,
R. Koster, D. Lohmann, S. Mahanama, K. Mitchell, O. Nasonova,
G.-Y. Niu, A. Pitman, J. Polcher,
A.B. Shmakin, K. Tanaka, B. Van den Hurk, S. Verant, D. Verseghy, and P. Viterbo: The
Rhone-Aggregation Land Surface Scheme Intercomparison Project: An Overview, J.
Climate, (V17 No1), 187-208, 2004.
Laura C. Bowling, Dennis P. Lettenmaier, Bart Nijssen,
Phil L. Graham, Douglas Clark, Mustapha El Maayar,
Richard Essery, Sven Goers, Florence Habet, Bart van der Hurk, Jiming Jing, Daniel Kahan, Dag Lohmann, Sarith Mahanama, David Mocko, Olga Nasonova, Patrick
Samuelsson, Andrey B. Shmakin,
Kumiko Takata, Diana Verseghy, Pedro Viterbo, Ma Xieyao, Yong Kang Xue, Zong-Liang Yang, Simulation of high latitude hydrological
processes in the Torne-Kalix basin: PILPS Phase 2e 1:
Experiment description and summary intercomparisons,
Global and Planetary Change, (38), 1-30, 2003.
Bart Nijssen, Laura C.
Bowling, Dennis P. Lettenmaier Phil L. Graham, Douglas Clark, Mustapha El Maayar, Richard Essery, Sven
Goers, Florence Habet, Bart van der
Hurk, Jiming Jing, Daniel Kahan, Dag Lohmann, Sarith Mahanama, David Mocko, Olga Nasonova, Patrick
Samuelsson, Andrey B. Shmakin,
Kumiko Takata, Diana Verseghy, Pedro Viterbo, Ma Xieyao, Yong Kang Xue, Zong-Liang Yang, Simulation of high latitude hydrological
processes in the Torne-Kalix basin: PILPS Phase 2e 2:
Comparison of model results with observations, Global and Planetary Change,
(38), 31-53, 2003.
Jayawardena A.W., and S.
P. P. Mahanama, Meso-Scale Hydrological Modeling:
Application to Mekong and
Presentations:
Mahanama,
S. P. P., R.D. Koster, R.H. Reichle and D. P. Lettenmaier. Contribution of Soil Moisture Information to
Streamflow Prediction in the Snowmelt Season: A Continental-Scale Analysis, 6th
International Scientific Conference on the Global Energy and Water Cycle, 24-28
August 2009, Melbourne, Australia.
Reichle, R. H., Kumar, S. V., Mahanama, S. P. P., and Koster, R.D. Bias estimation and
assimilation of land surface temperature, AGU Fall Meeting, Dec 15-19, 2008,
Reichle,
R. H., W. T. Crow, R. D. Koster, H. Sharif, and S. P. P. Mahanama, An Observing System Simulation Experiment (OSSE)
framework for the SMAP Level 4 soil moisture data assimilation products,
Microwave Land Hydrology workshop in
Lareef Zubair, Sarith
Mahanama, Janaki Chandimala,
and Neil Ward: Soil Moisture Memory and Predictability of Seasonal Streamflow
in
Sarith
Mahanama, R.D. Koster, R. H. Reichle, and L. Zubair (2008):
The role of Soil Moisture Initialization in Sub—seasonal and Seasonal
Streamflow Predictability- a Case Study in Sri Lanka, AGU Joint Assembly, 27–30
May 2008, Ft. Lauderdale, Florida.
Sarith P.P.
Mahanama, Randal D. Koster, Julio Bacmeister, and Rolf H. Reichle:
Land-atmosphere coupling strength in GEOS-5 AGCM, 88th AMS Annual
Meeting, New Orleans, Jan 20-24, 2008.
Reichle, R. H., W. T. Crow, R. D. Koster, H. O. Sharif, S. P. P. Mahanama (2007), The
contribution of soil moisture retrievals to land data assimilation products,
AGU Fall Meeting, Dec 10-14, 2007, San Francisco, USA.
Aihui Wang, Dennis P. Lettenmaier, Sarith Mahanama, and Randal D. Koster: Multimodel
Ensemble Reconstruction of Drought over the Continental U.S. NOAA’s 32st
Climate Diagnostics and Prediction Workshop (CDPW), Tallahase,
Florida, October 22-26, 2007.
Sarith P.P.
Mahanama, Randal D. Koster, Julio Bacmeister, and Rolf H. Reichle:
Land-atmosphere coupling strength in GEOS-5 AGCM, NEWS (NASA Energy and Water
cycle Study) 3rd
PI meeting,
Sarith P.P.
Mahanama, Rolf H. Reichle,
Lareef Zubair and Randal D.
Koster: Soil Moisture Memory and Predictability of Seasonal Streamflow in Sri
Lanka, AGU Joint Assembly, Acapulco, 22–25 May, 2007.
R H Reichle, W T Crow, R D Koster, H O Sharif, and S P P Mahanama
(2007): A data assimilation OSSE for assessing uncertainty and utility of soil
moisture retrievals, AGU Joint Assembly, Acapulco, 22–25 May, 2007.
Sarith P.P. Mahanama, Rolf H. Reichle, Lareef Zubair and Janaki Chandimala: Soil Moisture Memory and Predictability
of Seasonal Streamflow in Sri Lanka, INTERNATIONAL CONFERENCE ON “MITIGATION OF
THE RISK OF NATURAL HAZARDS”, Faculty of Engineering, the University of Peradeniya, Sri Lanka, March 27-28, 2007.
Lareef Zubair, Sarith
Mahanama, Janaki Chandimala,
and Neil Ward: Hydroclimatological Simulation over
Sri Lanka Using Global Reanalyses, AGU Fall Meeting,
San Francisco, CA, 2006.
Rolf H. Reichle, Wade T. Crow, Randal D.
Koster, Hatim Sharif, and Sarith Mahanama: Assessing the impact of errors in soil moisture
retrievals on their utility in a data assimilation,
AGU Fall Meeting,
Rolf H. Reichle, Wade T. Crow, Randal D.
Koster, Hatim Sharif, and Sarith Mahanama: Assessment of uncertainty and utility of soil
moisture retrievals in a data assimilation experiment, ,21th Conference of
Hydrology at 87th AMS Annual Meeting, San Antonio San Antonio, TX, Jan 2007.
Sarith Mahanama, Randal D. Koster, Julio T. Bacmeister,
Ping Liu, Max J. Suarez, and Rolf H. Reichle: Single
column model analysis of land-atmosphere coupling strength, 21th Conference of
Hydrology at 87th AMS Annual Meeting,
Randal Koster, Ping Liu, and Sarith
Mahanama: Impact of Soil Moisture on Precipitation: A Sensitivity
Study with the GEOS5 AGCM, NOAA’s 31st Climate Diagnostics and Prediction
Workshop (CDPW),
Sarith P.P. Mahanama, Randal D. Koster, and Ping Liu: Impact of Subsurface
Temperature Variability on Meteorological Variability: An AGCM Study, AGU Joint
Assembly,
Rolf H. Reichle, Randal D. Koster, Michael G.
Bosilovich, and Sarith
P.P. Mahanama: Biases and scaling in soil moisture and temperature data
assimilation, AGU Joint Assembly,
Rolf H. Reichle, Sarith Mahanama, Randal D. Koster, Jon D. Radakovich,
and Michael G. Bosilovich: A new look at the
assimilation of satellite retrievals of land surface temperature into a land
surface model, 20th Conference of Hydrology at 86th AMS Annual Meeting,
Atlanta, GA, Jan 2006
Mahanama, S.P.P., and R.D. Koster:, AGCM
biases in evaporation regime: Impact on soil moisture memory and
land-atmosphere feedback, 19th Conference Hydrology at 85th AMS Annual Meeting,
Sonia I. Seneviratne, Rolf Reichle, Randal D. Koster, Sarith P.P. Mahanama, M. Hirschi, and Christoph Schär (2004),
Basin-scale water-balance estimates of terrestrial water-storage variations:
Potential for data assimilation, in Proceedings of the 2nd international CAHMDA
workshop on: The Terrestrial Water Cycle: Modelling
and Data Assimilation Across Catchment Scales, edited by A.J. Teuling, H. Leijnse, P.A. Troch, J. Sheffield and E.F. Wood, pp. 19–22, Princeton,
NJ, October 25–27.
R.H. Reichle, R.D. Koster, and S.P.P. Mahanama (2004), Bias correction
of satellite soil moisture and assimilation into the NASA Catchment land
surface model, in Proceedings of the 2nd international CAHMDA workshop on: The
Terrestrial Water Cycle: Modelling and Data
Assimilation Across Catchment Scales, edited by A.J. Teuling,
H. Leijnse, P.A. Troch, J.
Sheffield and E.F. Wood, pp. 149–153, Princeton, NJ, October 25–27.
Mahanama, S.P.P., and R.D. Koster:, Impact of
GCM Climate Biases on the Simulation of Soil Moisture Memory, 18th Conference
Hydrology at 84th AMS Annual Meeting,
Mahanama, S.P.P., and R.D. Koster: Intercomparison soil moisture
memory in two land surface models, 17th Conference Hydrology at 83th AMS Annual
Meeting,
Mahanama, S.P.P.: Intercomparison soil moisture memory in two land
surface models, Brown bag seminar, hydrological sciences branch, NASA/GSFC, Dec
2002.
Mahanama, S.P.P. and R.D. Koster: Intercomparison soil moisture memory
in two land surface models, AGU-Spring 2002 meeting in
Jayawardena
A.W., and S.P.P.
Mahanama: Daily river discharge prediction using GCM generated atmospheric
data. In ‘Soil-Vegetation-Atmosphere Transfer Schemes and Large-Scale
Hydrological Models’, edited by Dolman, H., Pomeroy, J., Oki, T., and Hall.,
A., IAHS 270, pp 159-165, 2001
Jayawardena
A.W. and Mahanama S.P.P. (1997):
Limited area modeling of atmospheric circulation using a semi-Lagrangian semi-implicit finite difference scheme,
Proceedings of 5th Scientific Assembly of the International Association of
Hydrological Sciences, pp 61-64.
Professional Services:
Reviewer:
Manuscripts: Journal of Climate, Journal of Hydrometeorology, Journal
of Applied Meteorology, Global & Planetary Change, Journal of
Hydro-Environment Research, Geophysical Research Letters, Theoretical and
Applied Climatology, Hydrology and Earth System Sciences
Proposals:
NOAA CPPA Program, National Science
Foundation, NASA Earth and Space Science Fellowship, Canadian Foundation of
Climate and Atmospheric Sciences
Hobbies:
Member Cuong Nhu Karate Club at Goddard (since 2002) – Am Duong Do
Jo of the Cunong Nhu Oriental Martial Arts Association.