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, India

Sumant is a climate dynamicist. He has used observational analysis, theoretical diagnosis, and dynamical modeling to provide unique insights on tropospheric and stratospheric stationary waves, space-time structure of climate teleconnections, ocean-atmosphere interaction in tropical and subpolar basins, regional hydroclimate variability and droughts, seasonal and regional distribution of secular warming, transboundary water issues in Southeast Asia, and American and Asian monsoons. A current focus is unraveling the natural variability and secular change components of the climate record to advance understanding of the steep warming of the Northern Continents and loss of Arctic sea ice, and the seasonal prediction of South Asian summer monsoon rainfall.

Sumant obtained his M.Sc. degree 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. 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. He is a Fellow of the American Meteorological Society and the Royal Meteorological Society. Sumant was a Jefferson Science Fellow at the National Academy of Sciences and a Senior Science Advisor to the US State Department during 2016-17. He will be a Fulbright-Nehru Fellow during 2019-20. biosketch; brief-biosketch

Sahara Desert paper: Thomas*, N., and S. Nigam, 2018: 20th-Century Climate Change over Africa: Seasonal Hydroclimate Trends and Sahara Desert Expansion. J. Climate, 31, 3349-3370.    1920-2013 Seasonal Desert Advance (featured in the press release)
     UMD-CMNS Press Release; NSF Press Release; BAMS Paper of Note; Washington Post Coverage; Other Coverage.

American Meteorological Society's Information Statement on Climate Change
(Contributor; issued 15 April 2019)

  • AOSC 617:    Atmospheric and Oceanic Climate (Core course taught every Spring)
  • AOSC 610:    Dynamics of Atmosphere and Ocean - I (Core course in Fall; I teach in alternate years)
  • AOSC 611:    Dynamics of Atmosphere and Ocean - II (Course taught every Spring; I teach occasionally, last in 2010)
  • AOSC 658N: North American Hydroclimate (Elective course offered alternate years; last in 2012; Course projects)
  • HONR 238P: The Water Cycle and Water Wars of the American West (Honors Seminar; offered once in Fall 2007)
  • AOSC 671:    Ocean-Atmosphere Interaction (Elective course taught in Spring 2004 & 2005 with James Carton)
  • AOSC 498:    Undergraduate Senior Research Project (Sec # 2001)
  • AOSC 798:    Directed Graduate Research (Sec # 2001)
  • AOSC 899:    Doctoral Dissertation Research (Sec # 2001)
  • Undergraduate Research Opportunity
    Select sophomores and juniors can participate in climate analysis research through the Maryland Center for Undergraduate Research (MCUR). Project on Climate links between remote regions (Teleconnections): Structure & MechanismsRequired: Interest/expertise in statistical analysis (e.g., correlations, analysis of variance) and a GPA greater than 3.5. Familiarity with MATLAB or comparable software will be helpful. Background in Physics, Applied Math, or Atmospheric Sciences preferred.
    Research Interests
  • Laboratory for Experimental Hydroclimate Prediction: The South Asian Summer Monsoon Rainfall Forecast Project
  • South/Southeast Asian River Basins: Rainfall and Streamflow variations; Transboundary Water issues (conflicts, treaties)
  • Atmospheric teleconnections: Pentad evolution; dynamical mechanisms; contribution to extremes; hydroclimate
  • Recent warming of the Northern Continents: Seasonality; role of multidecadal natural variability; mechanisms
  • 20th-Century climate change over Africa: Seasonal hydroclimate trends and Sahara Desert expansion
  • Multidecadal variability and trends in Arctic sea ice and Antarctic surface warming: Structure and mechanisms
  • Decadal variability in the North Atlantic: Role of low-frequency NAO and the Gulf Stream excursions/detachments
  • Great Plains (GP) hydroclimate variability: Local and remote water sources; GP low-level jet 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 the nonstationary secular trend: SST PCc here
  • Characterization of El Nino's full influence on precipitation: the sub-optimality of the Nino 3.4 index regressions
  • Summer monsoon rainfall over the Gangetic Plain: Multidecadal variability and secular change; mechanisms
  • South Asian Regional Reanalysis: A NOAA - Ministry of Earth Sciences (India) collaboration
  • Diagnosis of 3D diabatic heating from ERA-40, ERA-15, ERA-Intrm & NCEP reanalyses; Monthly Heating here
  • Professional Preparation
    1984--1986    Massachusetts Institute of Technology, Cambridge; Postdoc in Climate Dynamics with Richard S. Lindzen
    1979--1984    Princeton University; M.A., Ph.D. in Geophysical Fluid Dynamics; Advisor: Isaac M. Held
    1978--1979    University of Washington, Seattle; Graduate studies in Atmospheric Sciences
    1973--1978    Indian Institute of Technology, Kanpur, India; M.Sc. in Physics (5-year program)
    1973--1978    National Science Talent Scholar, Government of India (national merit list, top five)
    1972/73          All India Higher Secondary Examination,CBSE, New Delhi (national merit list, top five)
    2020--2022    Distinguished Visiting Professor, School of Engineering, Indian Institute of Technology, Mandi, India
    2016--2018    Foreign Affairs Officer, US Department of State, Bureau of East Asian and Pacific Affairs (EAP)
                          Senior Science Advisor, Office of Multilateral Affairs (EAP/MLA), Lower Mekong Initiative
    2016--2017    Jefferson Science Fellow, National Academy of Sciences, Washington, DC
    2003--            Professor, Atmospheric and Oceanic Science & Earth System Science, University of Maryland, College Park
    2000--2003    Director, Large-scale Dynamic Meteorology Program, National Science Foundation
    2002--2003    Program Officer, Water Cycle Research; Biocomplexity in the Environment Initiative; National Science Foundation
    1987--2002    Research Professor, Research Scientist; Department of Meteorology, University of Maryland, College Park
    2019--2020    Fulbright-Nehru Fellow, The Fulbright Foundation and the US Department of State
    2017--2018    Chair, Drafting Committee, American Meteorological Society's Information Statement on Climate Change
    2016--2017    Jefferson Science Fellow, National Academy of Sciences; Jefferson fellowship photos
    2014--2018    Chair, Committee on Climate Variability and Change, American Meteorological Society
    2015--2018    Chair, Advisory Panel, Climate and Global Dynamics Laboratory (CGD), NCAR
    2013              Distinguished Alumnus Award, Indian Institute of Technology, Kanpur, India
    2012--            Member, International Commission on Dynamic Meteorology, IAMAS, IUGG
    2011--2012    Member, Board of Atmospheric Sciences and Climate, The National Academies, Washington, DC
    2008--2010    Member, Climate Research Committee, The National Academies, Washington, DC
    2006--            Fellow, American Meteorological Society, Boston
    2005--2006    Editor, Journal of Climate (climate science journal of the American Meteorological Society)
    2003--            Fellow, Royal Meteorological Society, UK
    201x--            Listed in American Men and Women in Science; Marquis Who's Who
    2017--2018    Advisory Committee, Geosciences Directorate (AC-GEO), National Science Foundation; press report
    2015--2018    Advisory Panel, National Center for Atmospheric Research (NCAR), Boulder
    201x              Committee of Visitors, NSF's Division of Atmospheric and Geospace Sciences
    2011--2014    Nominating Committee, University Corporation for Atmospheric Research (UCAR), Boulder
    2010--2014    Drought Interest Group, World Climate Research Programme, WMO
    2011--2012    Lead, CMIP5 Task Force - MAPP Program, NOAA Climate Program Office, Washington DC
    2007--2010    US Principal Scientist, US-NOAA and India-MoES Collaborative on South Asian Regional Reanalysis
    2006--2009    Drought Working Group, US Climate Variability & Predictability (CLIVAR) Program, Washington DC
    2005--2009    Co-Chair, Climate Variability Working Group, NCAR Community Earth System Model, Boulder CO
    2005--2006    Co-Chair, Phenomena, Observations, and Synthesis panel, US CLIVAR, Washington DC
    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--2018    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)
    Graduate Students
  • Rebecca Eager (Ph.D. Candidate, Fall 2016; Scientist, Johns Hopkins APL): Multidecadal variability of late-summer Arctic sea ice: Role of Atlantic Multidecadal Variability
  • Agniv Sengupta (Ph.D. Candidate, Spring 2018; thesis defense, November 2019): SST-based statistical prediction of South Asian summer monsoon rainfall distribution. The 2019 Monsoon Forecast. Dean's Fellow 2014-15; NCAR-CESM Tutorial Award 2017; Leah Thornton Lozano Graduate Fellow 2017; Goldhaber Travel Award 2017; Eugene Rasmusson Fellowship 2018.; UMD Outstanding Research Assistant 2018-19.
  • Ryan Clark (Ph.D. prospectus, Fall 2019; Lieutenant Commander, US Coast Guard): Seasonal and interannual variability of Arctic sea ice: Dynamical mechanisms.
  • Zhenchen Liu (Ph.D. Visiting Student, 2017-2018; Hohai University, Nanjing, China): Statistical reconstruction and prediction of droughts over China.
  • Undergraduate Students
  • Lu Zhang (UG Senior; 2017-18; co-advisor: Alfredo Ruiz-Barradas): Senior Thesis on Climate Change in the Indus River Basin.
  • Justin Hicks (UG Senior: 2017-18; co-advisor: Alfredo Ruiz-Barradas): Senior Thesis on Atmospheric Rivers: Origin and transports.
  • Vishal Ravi (Summer Research, 2016; UG:Univ. of Cambridge; GS:UC-Berkeley, 2018-): Seasonality in the Vertical Structure of Temperature Trends over North America. (Co-authored manuscript being reviewed by Intl. J. Climatology)
  • Doctoral Theses Advised (2007-Present)(ALL 17 Ph.Ds. and 12 MS)
  • Natalie P. Thomas (Ph.D., December 2018): On the Origin of Hydroclimate Change over Continents through Seasonally-Stratified Trends. Dean's Fellow 2014-15; NDSEG Fellow 2015-18; NASA-JPL Climate Science Summer School 2016; Goldhaber Travel Award 2017; Ann Wylie Green Fund Scholarship 2018; NCAR-CESM Tutorial Award 2018; Best Student Publication 2018; Postdoctoral Fellow, NASA-GSFC Global Modeling and Assimilation Office.
  • Ni Dai (Ph.D., Summer 2018; advisors: Phil Arkin & Sumant Nigam): El Nino Southern Oscillation and Related Precipitation in Recent Atmospheric Reanalyses and CMIP5 Model Simulations; Postdoctoral Fellow (with Brian Soden), RSMAS, Univ. of Miami.
  • 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 Fellowship 2013; Best Student Publication 2015; Best Doctoral Dissertation 2016; Staff Meteorologist, NOAA Climate Prediction Center, College Park, MD.
  • Yongjing Zhao (Ph.D., Summer 2014; advisors: Eugenia Kalnay & Sumant Nigam): Application of breeding to nonlinear waves and diurnal cycle in the MARS reanalysis., Vice President, Predictive Modeling, Citibank, Washington, DC
  • 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 Fellowship 2014; 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. Research 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 (2015-2018); Director, National Windstorm Impact Reduction, National Institute of Standards and Technology (NIST), MD.
  • Recent Presentations (2010-Present;  2009-2010;  Conference Sessions)
  • School of Marine and Atmospheric Sciences, Stony Brook University (27 February 2019)
  • The Isaac Held Symposium, Princeton University, NJ (October 2018)
  • IAMAS session on the Seasonal Cycle, Intl. Commission on Dynamic Meteorology, Cape Town, S Africa (31 August 2017)
  • US Embassy, New Delhi, India; Economic, Environment, Science, and Technology Section (24 August 2017)
  • US State Department, Bureau of East Asian and Pacific Affairs, Office of Multilateral Affairs (15 August 2017)
  • National Academy of Sciences, Jefferson Science Fellows Distinguished Lecture Series (1 August 2017)
  • The Stimson Center, Southeast Asia Program's Roundtable on Mekong Water Resources (12 July 2017)
  • Vietnam National Mekong Committee, Hanoi, Vietnam (8 May 2017)
  • Fourth Santa Fe Conference on Global and Regional Climate Change, Santa Fe, New Mexico (5-10 February 2017)
  • 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 George 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)
  • 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)
  • 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)
  • Session Chair, The Mike Wallace Symposium, University of Washington, Seattle (28 September 2010)
  • Panelist, Innovation in Research Cooperation, IIT Kanpur Golden Jubilee Celebrations, Washington DC (9 July 2010)
  • Organizer, CRC Forum on Atlantic Multidecadal Oscillation, The National Academies, DC (27 April 2010)
  • GFDL Seminar, Princeton University, Princeton (18 March 2010)
  • Department of Earth & Planetary Sciences Seminar, University of Tokyo, Japan (2 November 2009)

    Reference Works
  • Nigam, S. and N. Thomas, 2019: The Sahara Desert Hydroclimate and Expanse: Natural Variability and Climate Change. Invited Chapter in Encyclopedia of the World's Biomes, ELSEVIER | Major Reference Works (in press).
  • 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.

    Present--2010 (*Student; **Research Associate)
  • Nigam, S., and A. Sengupta*, 2019: The Full Extent of El Nino's Precipitation Influence on the United States and the Americas: The Sub-Optimality of the Nino 3.4 SST Index. To be submitted to the J. Climate in July.
  • Nigam, S., N. P. Thomas*, and A. Ruiz-Barradas**, 2019: Surface Warming over Antarctica: Origin and Mechanisms. To be submitted in June.
  • Sengupta*, A., S. Nigam, S. Baxter, and A. Ruiz-Barradas**, 2019: Anatomy of the 2015-16 El Nino: Classical Onset with Complex Evolution. To be submitted to the J. Climate in June.
  • Nigam, S., N. Thomas*, A. Ruiz-Barradas**, and A. Sengupta*, 2019: Significant Contribution of Multidecadal Ocean Variability in Recent Warming of Northern Continents. To be submitted in May.
  • Nigam S., R. E. Eager*, and A. Ruiz-Barradas**, 2019: Arctic Sea Ice Loss after Factoring for Multidecadal Variability. To be submitted in April.
  • Information Statement on Climate Change (April 2019; Contributor), American Meteorological Society, Boston.
  • Thomas*, N., V. Ravi*, and S. Nigam, 2019: Seasonality in the Vertical Structure of Temperature Trends over North America. (Submitted to Intl. J. Climatology in June)
  • Sengupta*, A., and S. Nigam, 2019: The Northeast Winter Monsoon over the Indian Subcontinent and Southeast Asia: Evolution, Interannual Variability, and Model Simulations. J. Climate, 32, 231-249.
  • Ruiz-Barradas**, A., L. Chafik, S. Nigam, and S. Hakkinen, 2018: Recent Subsurface North Atlantic Cooling Trend in context of Atlantic Decadal-to-Multidecadal Variability. Tellus A: Dynamical Meteorology & Oceanography, 70, 1481688,
  • Thomas*, N., and S. Nigam, 2018: Sahara Desert Expands in the 20th-Century. Bull. Amer. Meteor. Soc., 99, Papers of Note, 1123-1124.
  • Ruiz-Barradas**, A., and S. Nigam, 2018: Hydroclimate Variability and Change over the Mekong River Basin: Modeling, and Predictability and Policy Implications. J. Hydrometeor., 19, 849-869.
  • Thomas*, N., and S. Nigam, 2018: 20th-Century Climate Change over Africa: Seasonal Hydroclimate Trends and Sahara Desert Expansion. J. Climate, 31, 3349-3370. The 1920-2013 Desert Creep (seasonal)
    UMD-CMNS Press Release; NSF Press Release; Washington Post Coverage; Other Coverage.
  • Nigam, S., A. Ruiz-Barradas**, and L. Chafik, 2018: Gulf Stream Excursions and Sectional Detachments Generate the Decadal Pulses in the Atlantic Multidecadal Oscillation. J. Climate, 31, 2853-2870.
  • 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, 30, 6521-6541.
  • Lemone, M. A., S. Nigam, and J. M. Wallace (2017): Eugene M. Rasmusson (1929-2015). Memorial Tributes, Volume 21, The National Academies Press, Washington, DC.
  • 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
  • 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.
  • 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) in Dynamics and Predictability of Large-scale High-Impact Weather and Climate Events. Cambridge University Press; ISBN: 9781316468746.
  • Nigam, S., Y. Zhao*, A. Ruiz-Barradas**, and T. Zhou, 2016: 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 (Editors: Michael Ghil, Mojib Latif, Mike Wallace, and C.P. Chang) World Press, 376pp.
  • Wallace, J.M., and S. Nigam, 2015: Eugene M. Rasmusson (1929-2015). Bull. Amer. Meteor. Soc., 96, 1804-1808.
  • 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.
  • Zhao*, Y., and S. Nigam, 2015: The Indian Ocean Dipole: A Monopole in SST. J. Climate, 28, 3-19.
  • Nigam, S. and S. Baxter*, 2015: Teleconnections. Invited contribution in Encyclopedia of Atmospheric Sciences (2nd Edition; Editors: G. North, F. Zhang, and J. Pyle) Academic Press, Elsevier Science, London, 90-109.
  • Ruiz-Barradas**, A, and S. Nigam, 2013: Atmosphere-Land-surface Interactions over the Southern Great Plains: Characterization from Pentad Analysis of ARM Observations and NARR. J. Climate, 26, 875-886.
  • 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.
  • Baxter*, S., and S. Nigam, 2013: A Sub-Seasonal Teleconnection Analysis: PNA Development and Its Relationship to the NAO. J. Climate, 26, 6733-6741.
  • Ruiz-Barradas**, A., S. Nigam, and A. Kavvada*, 2013: The AMO in 20th Century Climate Simulations: Uneven Progress from CMIP3 to CMIP5. Climate Dynamics, DOI 10.1007/s00382-013-1810-0.
  • 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.
  • 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.
  • Grodsky, S., J. Carton, S. Nigam, and Y. Okumura, 2012: Tropical Atlantic Biases in CCSM4. J. Climate, 25, 3684-3701.
  • 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, 0.1029/2011GL048650.
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • Weaver*, S.J., and S. Nigam, 2011: Recurrent Supersynoptic Evolution of the Great Plains Low-Level Jet. J. Climate, 24, 575-582.
  • Ruiz-Barradas**, A., and S. Nigam 2010: SST - North American hydroclimate links in AMIP simulations of the Drought Working Group models: A proxy for the idealized drought modeling experiments. J. Climate, 23, 2585-2598.
  • Ruiz-Barradas**, A., and S. Nigam 2010: Great Plains Precipitation and its SST Links in 20th Century Climate Simulations, and 21st and 22nd Century Climate Projections. J. Climate, 23, 6409-6429.
  • Nigam, S., and M. Bollasina*, 2010: The 'Elevated Heat Pump' Hypothesis for the Aerosol-Monsoon Hydroclimate Link: "Grounded" in Observations? J. Geophys. Res., 115, D16201, doi:10.1029/2009JD013800.

    Science Cover (28 May 2004)