Sumant Nigam's Homepage

Sumant Nigam
Department of Atmospheric & Oceanic Science (AOSC)
Earth System Science Interdisciplinary Center (ESSIC)
Laboratory for Experimental Hydroclimate Prediction

3419 Atlantic Bldg. (224), 4254 Stadium Drive
University of Maryland, College Park, MD 20742, USA
Voice:(301) 405-5381 (5391); Fax:(301) 314-9482
Web Page:

Ph.D., Geophysical Fluid Dynamics 1984, Princeton University, USA
M.Sc., Physics 1978  (5-yr program), Indian Institute of Technology, Kanpur

Sumant Nigam obtained his in Physics from the 5-year integrated science and engineering program at the Indian Institute of Technology, Kanpur, supported by the National Science Talent scholarship. He received his Ph.D. in Geophysical Fluid Dynamics from Princeton University in 1984, and postdoctoral training (1984-1987) at the Massachusetts Institute of Technology in the department of Earth, Atmospheric & Planetary Sciences. He came to the University of Maryland in 1987. Sumant was director of the Large-scale Dynamic Meteorology program at the US National Science Foundation from 2000-2002. Sumant is a Fellow of the American Meteorological Society and the Royal Meteorological Society, and a Jefferson Science Fellow of the National Academies of Science, Engineering, and Medicine. Bio-sketch (one-page; half-page).

  • HONR 238P: The Water Cycle and Water Wars of the American West (Honors Seminar; offered once in Fall 2007)
  • AOSC 610:    Dynamics of Atmosphere and Ocean - I (Core course in Fall; teach alternate years)
  • AOSC 611:    Dynamics of Atmosphere and Ocean - II (Core course in Spring; teach occasionally, last in 2010)
  • AOSC 617:    Atmospheric and Oceanic Climate (Core course in Spring; teach every year)
  • AOSC 658N North American Hydroclimate (Elective offered alternate years since Fall 2005, last in 2012; Course projects)
  • AOSC 671:    Ocean-Atmosphere Interaction (Elective taught in Spring 2004 & 2005 with James Carton)
  • AOSC 798/899: Directed Graduate/Dissertation Research (Sec # 2001)
  • Undergraduate Research Opportunity
    Select sophomores and juniors can participate in exciting climate analysis research through the Maryland Center for Undergraduate Research (MCUR). My MCUR project is on Climate links between remote regions (Teleconnections): Structure and mechanismsRequired: Interest/expertise in statistical analysis (e.g., correlations, analysis of variance) and a GPA of at least 3.50. Familiarity with MATLAB or comparable software packages will be helpful, as will be exposure to computer programming (Fortran) and UNIX OS. Background in Physics, Applied Math, or Environmental Sciences is preferred.
    Research Interests
  • Laboratory for Experimental Hydroclimate Prediction: The SST-based 2016 South Asian Summer Monsoon Rainfall Forecast
  • Atmospheric teleconnections: Pentad evolution; dynamical mechanisms; contribution to extremes; hydroclimate
  • Recent warming of the Northern Continents: Contribution of multidecadal natural variability; mechanisms
  • Multidecadal variability and secular change in South Asian monsoon rainfall
  • Seasonal and interannual variations of Arctic sea ice: Influence of atmospheric circulation and heat transports
  • Decadal/Multidecadal variability in the Atlantic and Pacific: Surface/subsurface structure of AMO and PDV
  • US Great Plains hydroclimate variability: Local and remote water sources; GPLLJ variability; SST links
  • North American Droughts: Analysis and SST-based reconstruction (and prediction) of major 20th Century episodes
  • Evolution-centric SST analysis: Separation of natural variability and nonstationary secular trend: SST PCc are here
  • Seasonal/interannual variations of sea-level pressure anticyclones (e.g., Bermuda High): Role of midlatitudes
  • South Asian summer monsoon dynamics: Origin of the "heat low"; impact of the expanding Thar desert
  • Absorbing aerosols and Asian summer monsoon hydroclimate: Delayed onset from semi-direct effects
  • South Asian Regional Reanalysis: A NOAA - Ministry of Earth Sciences (India) collaboration
  • Evolution of the eastern tropical Pacific climate: Ocean-atmosphere coupling; stratus cloud development
  • Diagnosis of 3D diabatic heating from ERA-40, ERA-15, and NCEP reanalyses; Monthly Heating here
  • Dynamical diagnosis of decadal climate variability and secular change in IPCC-AR5's 20th century simulations
  • Brief CV
    1972/73:      All India Higher Secondary Examination,CBSE, New Delhi (national merit list, top five)
    1973-1978:   National Science Talent Scholar, Government of India (national merit list, top five)
    1973-1978:   Indian Institute of Technology, Kanpur, India; M.Sc. in Physics (5-year program)
    1978-1979:   University of Washington, Seattle; Graduate studies in Atmospheric Sciences
    1979-1984:   Princeton University; M.A., Ph.D. in Geophysical Fluid Dynamics; Advisor: Isaac M. Held
    1984-1986:   Massachusetts Institute of Technology, Cambridge; Postdoc with Richard S. Lindzen
    1987-       :   University of Maryland, College Park; Research Scientist, Research Professor, Professor
    2000-2003:   US National Science Foundation; Director, Large-scale Dynamic Meteorology Program
    2017-        :   US State Department; Senior Sci. Advisor & Foreign Aff. Officer, Bureau of East Asian & Pacific Affairs (EAP/MLA)
    2017-2018:  Chair, Drafting Committee, American Meteorological Society's Information Statement on Climate Change
    2017-2019:  Advisory Committee, Geosciences Directorate (AC-GEO), US National Science Foundation, Arlington, VA
    2016-       :   Jefferson Science Fellow, The National Academies of Science, Engineering, and Medicine, Washington, DC
    2015-       :   Advisory Panel, National Center for Atmospheric Research (NCAR), Boulder
    2015-       :   Chair, Advisory Panel, Climate and Global Dynamics Laboratory (CGD), NCAR
    2014-       :   Chair, AMS Committee on Climate Variability and Change, American Meteorological Society
    2013-       :   Distinguished Alumnus Award, Indian Institute of Technology, Kanpur, India
    2012-       :   International Commission on Dynamic Meteorology, IAMAS, IUGG
    2011-2012:   Lead, CMIP5 Task Force - MAPP Program, NOAA Climate Program Office, Washington DC
    2011-2014:   Nominating Committee, UCAR, Boulder
    2011-2012:   Board of Atmospheric Sciences and Climate, The National Academies, Washington DC
    2008-2010:   Climate Research Committee, The National Academies of Science, Engineering, and Medicine, Washington DC
    2010-       :   Drought Interest Group, World Climate Research Programme, WMO
    2007-2010:   US Principal Scientist, US-NOAA and India-MoES Collaborative on South Asian Regional Reanalysis
    2006-       :   Fellow, American Meteorological Society, Royal Meteorological Society
    2006-2009:   Drought Working Group, US CLIVAR, Washington DC
    2005-2006:   Editor, Journal of Climate (an AMS publication)
    2005-2006:   Co-Chair, Phenomena, Observations and Synthesis panel, US CLIVAR, Washington DC
    2005-2009:   Co-Chair, Climate Variability Working Group, NCAR Community Climate System Model, Boulder CO
    2005-2006:   Science Steering Committee, US CLIVAR, Washington DC
    2004-2005:   Co-Chair, US CLIVAR Pacific Implementation Panel, Washington DC
    2003-2005:   Committee on Climate Variability and Change, American Meteorological Society
    2014-2015:   Co-Chair, 27th Conference on Climate Variability and Change, American Meteorological Society 2011-       :   Organizer, The Eugene Rasmusson Lectures, Dept. of Atmospheric & Oceanic Science, University of Maryland
    2010-       :   U Md. Representative, University Corporation for Atmospheric Research (UCAR)
    2008-       :   Member, India International Center, New Delhi, India
    2007        :   Co-Chair, The Eugene Rasmusson Symposium; Symposium booklet; Gene's Address; AMS Annual Meeting
                        Eugene Martin Rasmusson (27 February 1929 - 22 March 2015)
                        UMD Obituary; Obituary in BAMS; Interment at Arlington National Cemetery (some pictures)
    Current Students
  • Rebecca Eager (prospectus defense in Fall 2016; Scientist, Johns Hopkins APL): Multidecadal variability of late-summer Arctic sea ice: Role of Atlantic Multidecadal Variability
  • Ryan Clark (prospectus defense in Fall 2016; LT, US Coast Guard): Seasonal and interannual variability of Arctic sea ice: Dynamical mechanisms.
  • Natalie Thomas (joined 2014): Seasonality in the secular warming of the Northern Continents. National Defense Science and Engineering Graduate Fellowship (2015-2018).
  • Agniv Sengupta (joined 2014): SST-based statistical prediction of South Asian summer monsoon rainfall distribution; 2016 Monsoon Rainfall Forecast. Supported by Dr. M. Rajeevan, National Monsoon Mission, Government of India, New Delhi.
  • Ni Dai (Ph.D. Candidate, Winter 2015; co-advisor; research advisor: Phil Arkin, ESSIC): ENSO precipitation structure in observations and climate simulations.
  • Doctoral Theses Advised (2007-Present;  ALL)
  • Stephen Baxter (Ph.D., Winter 2015/16): Observed Teleconnections in Northern Winter: Subseasonal Evolution and Tropical Linkages. AMS Graduate Fellowship 2010; CMNS Dean's Fellowship 2011; Eugene Rasmusson Graduate Fellowship 2013; Best Graduate Student Paper 2015; Staff Meteorologist, NOAA Climate Prediction Center, College Park, MD.
  • Yongjing Zhao (Ph.D., Summer 2014; defense on 1 August; advisors: Eugenia Kalnay & Sumant Nigam): Application of breeding to nonlinear waves and diurnal cycle in the MARS reanalysis., Big Data Specialist, Capital One Bank, McLean, VA
  • Argyro Kavvada (Ph.D., Summer 2014; advisors: Sumant Nigam & Alfredo Ruiz-Barradas): Atlantic Multidecadal Variability: Surface and subsurface thermohaline structure and hydroclimate impacts. Eugene Rasmusson Graduate Fellowship 2014; Defense and Intelligence Group, Booz Allen Hamilton, NASA Headquarters, Washington DC
  • Kye-Hwan Kim (Ph.D., May 2013): Statistical Modeling of Atlantic hurricane activity using atmospheric reanalyses and IPCC simulations and projections. Lt. Colonel, South Korea Air Force, Seoul.
  • Massimo Bollasina (Ph.D., April 2010): Surface and aerosol effects on the South Asian monsoon hydroclimate. Wylie Dissertation Fellowship, Univ. of Maryland Graduate School 2008-2009; Best Student Seminar 2008; Global Climate Change Fellowship, The Green Fund Foundation 2009; Best Doctoral Dissertation 2010. Postdoc, NOAA/GFDL, Princeton University (2010-2013); WCRP Young Scientist Award 2011;WMO Norbert Gerbier-MUMM International Award 2013;
    AGU James R. Holton Junior Scientist Award 2013; Assistant Professor, University of Edinburgh, Scotland (2013-).
  • Bin Guan (Ph.D., October 2008): Pacific decadal SST variability and North American droughts. Wylie Dissertation Fellowship, Univ. of Maryland Graduate School, 2007-2008; Univ. of Maryland Goldhaber Travel Award 2007. Visiting Scientist, Climate Physics Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena.Bin Guan in NASA/JPL News.
  • Ching-Yee Chang (Ph.D., July 2008; advisors: Sumant Nigam & James Carton): Seasonal and interannual ocean-atmosphere variability in the tropical Atlantic: Observed structure and model representation. Univ. of Maryland Goldhaber Travel Award 2007; Visiting Scholar, Department of Geography, University of California, Berkeley.
  • Megan Linkin (Ph.D., May 2008): North Pacific climate variability and Arctic sea ice. AMS Global Change Travel Scholarship 2005-07; University of Maryland Goldhaber Travel Award 2006. Atmospheric Peril Specialist. Vice President, Global Partnerships, Swiss Re, Armonk, New York. Megan in NY Times.
  • Steven Chan (Ph.D., April 2008): On the summertime development of the North Pacific sea-level pressure anticyclone. NASA Earth System Science Fellow, 2004-07; NSF East Asian-Pacific Summer Inst. Fellow 2004. Scientist, UK Met Office, Exeter.
  • Scott Weaver (Ph.D., May 2007): The Great Plains Low-level Jet: Structure, variability mechanisms & hydroclimate impacts. Center for Teaching Excellence Distinguished Teaching Assistant Award, 2004-05;  Research Meteorologist, NOAA Climate Prediction Center, College Park;  Presidential Early Career Award for Scientists and Engineers (PECASE) 2012; Senior Scientist, Environmental Defense Fund, Washington DC (2015-).
  • Recent Presentations (2011-Present;  2009-2010;  Conference Sessions)
  • National Institute of Oceanography Seminar, Government of India, Dona Paula, Goa, India (8 March 2016)
  • Biennial Rosenburg International Forum for Water Policy, Ninth Forum, Panama City, Panama (27-28 January 2016)
  • University of Edinburgh, School of Geosciences Seminar, Edinburgh (12 March 2015)
  • Ansal University: Workshop on Impacts of Aerosols and Changing Climate on Monsoons, India (12-15 January 2015)
  • Japan Society for Promotion of Science - Climate Change Symposium, Cosmos Club, Washington, DC (22 February 2013)
  • Department of Atmospheric Sciences, National Taiwan University (NTU), Taipei (21 September 2012)
  • NTU Intl Science Conference on Climate Change; Taida Institute for Mathematical Sciences, NTU, Taipei (17-20 Sept. 2012)
  • National Monsoon Mission: Consultancy Meeting; Indian Institute of Tropical Meteorology, Pune (11-12 September 2012)
  • The Philander Symposium, Princeton University, NJ (6 September 2012)
  • LASG Seminar, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China (10 August 2012)
  • ICDM Workshop on Dynamics & Predictability of High Impact Weather & Climate Events, Kunming, China (6-9 August 2012)
  • Department of Civil and Environmental Engineering, University of Illinois, Urbana-Champaign (22 June 2012)
  • WCRP Global Drought Information Workshop, Frascati, Italy (11-13 April 2012)
  • Atmospheric Science & Physical Oceanography (CASPO) Seminar, University of California, San Diego (5 April 2012)
  • Institute for Terrestrial & Planetary Atmospheres, State University of New York, Stony Brook (21 March 2012)
  • Indian Institute of Tropical Meteorology, Pune, India; Golden Jubilee Celebrations, 21-25 February 2012
  • Department of Civil and Environmental Engineering, University of California, Irvine (19 December 2011)
  • NRC Workshop on Himalayan Glaciers, Hydrology and Climate Change, Washington, DC (19-20 October 2011)
  • GEWEX TRACE Workshop: The atmosphere/climate system. Silver Spring, MD (18-20 April 2011)
  • WCRP Workshop on Drought Predictability and Prediction in a Changing Climate, Barcelona, Spain (2-5 March 2011)
  • Caribbean GPS Observational Network, COCONet Workshop, San Juan, Puerto Rico (3-4 February 2011)
  • 25th Conference on Hydrology, AMS Annual Meeting, Seattle (27 January 2011)
  • NRC Committee on Climate, Energy, and National Security, Washington, DC (10-11 January 2011).
  • National Center for Medium Range Weather Forecasting Seminar, Ministry of Earth Sciences, India (5 January 2011)

    Reference Works
  • Nigam, S. and S. Baxter, 2014: Teleconnections. Invited contribution in Encyclopedia of Atmospheric Sciences  (2nd Edition; Editors: Gerald North, Fuqing Zhang and John Pyle) Academic Press, Elsevier Science, London, 90-109.
  • Nigam, S., 2003: Teleconnections. Encyclopedia of Atmospheric Sciences; Editors: J.R. Holton, J.A. Pyle & J.A. Curry; Academic Press, Elsevier Science, London, 2243-2269.
  • Nigam, S., and E. DeWeaver, 2003: Stationary Waves (Orographic and Thermally forced). Encyclopedia of Atmospheric Sciences; Editors: J.R. Holton, J.A. Pyle & J.A. Curry; Academic Press, Elsevier Science, London, 2121- 2137.

    Pre-2005    2005-2010

    1. Nigam, S., B. Guan, and A. Ruiz-Barradas, 2011: Key role of the Atlantic Multidecadal Oscillation in 20th century drought and wet periods over the Great Plains. Geophys. Res. Lett., 38, L16713, doi:10.1029/2011GL048650.
    2. Nigam, S., and B. Guan, 2011: Atlantic Tropical Cyclones in the 20th Century: Natural Variability and Secular Change in Cyclone Count. Climate Dynamics, 36:2279-2293 DOI 10.1007/s00382-010-0908-x.
    3. Nigam, S., and M. Bollasina, 2011: Reply to comment by K. M. Lau and K. M. Kim on "'Elevated heat pump' hypothesis for the aerosol-monsoon hydroclimate link: 'Grounded' in observations? J. Geophys. Res. 116, D07204, doi:10.1029/2010JD015246.
    4. Bollasina, M., and S. Nigam, 2011: The Summertime "Heat" Low over Pakistan / Northwestern India: Evolution and Origin. Climate Dynamics, 37:957-970 DOI 10.1007/s00382-010-0879-y.
    5. Bollasina, M., and S. Nigam, 2011: Modeling of Regional Hydroclimate Change over the Indian Subcontinent: Impact of the Expanding Thar Desert. J. Climate, 24, 3089-3106.
    6. Bollasina, M., and S. Nigam, 2011: Increasing desertification of Northwestern India can adversely impact the South Asian monsoon. GEWEX News, 21, No. 2, 8-10.
    7. Weaver, S.J., and S. Nigam, 2011: Recurrent Supersynoptic Evolution of the Great Plains Low-Level Jet.
      J. Climate, 24, 575-582.
    8. Grodsky, S., J. Carton, S. Nigam, and Y. Okumura, 2012: Tropical Atlantic Biases in CCSM4. J. Climate, 25, 3684-3701.
    9. Ruiz-Barradas, A, and S. Nigam, 2013: Atmosphere-Land-surface Interactions over the Southern Great Plains: Characterization from Pentad Analysis of DOE-ARM Field Observations and NARR Reanalysis. J. Climate, 26, 875-886.
    10. Kavvada, A., A. Ruiz-Barradas, and S. Nigam, 2013: AMO's Structure and Climate Footprint in Observations and IPCC AR5 Climate Simulations. Climate Dynamics, DOI 10.1007/s00382-013-1712-1.
    11. Baxter, S., and S. Nigam, 2013: A Sub-Seasonal Teleconnection Analysis: PNA Development and Its Relationship to the NAO. J. Climate, 26, 6733-6741.
    12. Ruiz-Barradas, A., S. Nigam, and A. Kavvada, 2013: The Atlantic Multidecadal Oscillation in 20th Century Climate Simulations: Uneven Progress from CMIP3 to CMIP5. Climate Dynamics, DOI 10.1007/s00382-013-1810-0.
    13. Sheffield, J., et al. (including S. Nigam), 2013: North American Climate in CMIP5 Experiments. Part I: Evaluation of Historical Simulations of Continental and Regional Climatology. J. Climate, 26, 9209-9245.
    14. Sheffield, J., et al. (including S. Nigam), 2013: North American Climate in CMIP5 Experiments. Part II: Evaluation of Historical Simulations of Intra-Seasonal to Decadal Variability. J. Climate, 26, 9247-9290.
    15. Nigam, S. and S. Baxter, 2014: Teleconnections. Invited contribution in Encyclopedia of Atmospheric Sciences  (2nd Edition; Editors: Gerald North, Fuqing Zhang and John Pyle) Academic Press, Elsevier Science, London, 90-109.
    16. Sheffield, J., et al. (including S. Nigam), 2014: Regional Climate Processes and Projections for North America: CMIP3/CMIP5 differences, attribution and outstanding issues. NOAA Technical Report OAR CPO-2.
    17. Nigam, S., Y. Zhao, A. Ruiz-Barradas, and T. Zhou, 2015: The South-Flood North-Drought Pattern over Eastern China and the Drying of the Gangetic Plain: Observations, Simulations, and Origin. Invited book chapter (pgs.347-360) in Climate Change: Multidecadal and Beyond (410pp.)  (Editors: Michael Ghil, Mojif Latif, Mike Wallace and C.P. Chang), World Press. ISBN:9789814579926
    18. Zhao, Y., and S. Nigam, 2015: The Indian Ocean Dipole: A Monopole in SST. J. Climate, 28, 3-19.
    19. Baxter, S., and S. Nigam, 2015: Key Role of North Pacific Oscillation/West Pacific Pattern in Generating the Extreme 2013-2014 North American Winter. J. Climate, 28, 8109-8117.
    20. Wallace, J. M., and S. Nigam, 2015: Eugene M. Rasmusson (1929-2015). Bull. Amer. Meteor. Soc., 96, 1804-1808.
    21. Nigam, S., and A. Ruiz-Barradas, 2016: Key Role of the Atlantic Multidecadal Oscillation in 20th Century Drought and Wet Periods over the US Great Plains and the Sahel. Invited book chapter (pgs.255-270) Dynamics and Predictability of Large-scale High-Impact Weather and Climate Events  (Editors: Jianping Li, Richard Swinbank, Hans Volkert and Richard Grotjahn) Cambridge University Press. ISBN:9781316468746
    22. Nigam, S., 2016: Atmospheric Science of Humid Areas: Why are humid areas humid? Invited peer-reviewed book chapter, Rosenberg International Forum on Water Policy, California Institute for Water Resources, University of California; to be published by Routledge Press, London.
    23. Chafik, L, and co-authors (S Nigam), 2016: Global Linkages Originating from Decadal Oceanic Variability in the Subpolar North Atlantic. Geophys. Res. Lett. , 10.1002/2016GL071134
    24. Nigam, S., N. Thomas, A. Ruiz-Barradas, and S. Weaver, 2017: Striking Seasonality in the Secular Warming of the Northern Continents: Structure and Mechanisms. J. Climate (in press; submitted 20th October 2016; accepted 3rd April).
    25. Nigam, S., A. Ruiz-Barradas, and L. Chafik, 2017: Gulf Stream Excursions Generate the Decadal Pulses in Atlantic Multidecadal Oscillation. J. Climate (submitted 6th January; under revision).
    26. Thomas, N., and S. Nigam, 2017: 20th-Century Climate Change over Africa: Seasonal Variation in Hydroclimate Trends and Sahara Desert Extent. Submitted to the J. Climate on 21st March.
    27. Thomas, N., V. Ravi, and S. Nigam, 2017: Seasonality in the Vertical Structure of Temperature Trends over North America. To be submitted to the J. Climate on 12th May.

      Science Cover (28 May 2004)
      Acknowledgements: I thank Owen Thompson for his advice and help with web-page development; Owen generously provided his web-page template and photo-editing skills.