Basic Information

Environmental Informatics Laboratory
Web site


Courses - Undergraduate
Numerical Analysis, Dynamics
Courses - Graduate
High Performance Computing, Numerical Ocean-Atmosphere Modeling using OpenCL, Computational Fluid Dynamics


Climate Dynamics
Educational Background, Biography
PhD (Atmospheric Sciences), Indian Institute of Science, Bangalore, India
Current Research Theme
GPS meteorology, Climate dynamics
Key Topic
Numerical Modeling, Super El Nino, Indian Ocean Dipole, Sensor network, Machine Learning
Affiliated Academic Society
American Geophysical Union, Japan Geophysical Union


School days' Dream
Current Dream
Favorite Books
Messages for Students
Publications other than one's areas of specialization

Main research

Analysing Climate data using Machine Learning Algorithms

Analyze climate data using self organizing maps

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Indian Ocean Dipole

The Indian Ocean Dipole is a climate phenomenon that affects global climate. It is an irregular oscillation with positive and negative phases. In the positive phase, sea surface temperatures of the eastern Indian Ocean experience unusual cooling. This is soon followed by a warming of sea surface temperatures in the western Indian Ocean. These changes lead to a large shift in rainfall from the eastern towards the western Indian Ocean, and is consequently associated with drought in the eastern and floods in the western Indian Ocean.   We study the mechanisms by which the Indian Ocean Dipole is generated using computer models. Areas of research include Indian Ocean Dipole dynamics, its impacts on global climate and how it interacts with the El Nino Southern Oscillation.

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Super El Nino

What processes are responsible for Super El Ninos are explored using computational modeling approaches.

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Tracking Clouds and Rain with low cost GPS chips

GPS or Global Positioning System is a popular technology used for positioning and navigation. However GPS signals can also be used for scientific applications. One application is to track clouds and rain. This is possible because GPS signals are delayed by the effect of water vapor in the atmosphere. In our lab we are exploring the use of low cost GPS chips for tracking clouds and rain. The research project will involve collaboration with Fukushima Renewable Energy Center of AIST ( We have installed several GPS receivers at FREA including high end and low end versions. The research will involve intercomparison of data from the receivers. It also will develop machine learning algorithms to map water vapour to clouds.

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Dissertation and Published Works

1.Title: A dipole mode in the tropical Indian Ocean Author(s): Saji, N. H.; Goswami, B. N.; Vinayachandran, P. N.; et al. Source: Nature Volume: 401 Pages: 360-363 Published: 1999 Times Cited: 1582 DOI: 10.1038/43855 added 24-May-10
2.Title: Possible Impacts of Indian Ocean Dipole Mode events on global climate Author(s): Saji, N. H.; Yamagata, T. Source: Climate Research Volume: 25 Pages: 151-169 Published: 2003 Times Cited: 259 DOI: 10.3354/cr025151 added 24-May-10
3.Title: Individual and combined influences of ENSO and the Indian Ocean Dipole on the Indian Summer Monsoon Author(s): Ashok, K.; Guan, Z.; Saji, N. H.; et al. Source: Journal of Climate Volume: 17 Pages: 3141-3155 Published: 2004 Times Cited: 145 DOI: 10.1175/1520-0442(2004)0172.0.CO;2 added 24-May-10
4.Title: Structure of SST and surface wind variability during Indian Ocean Dipole Mode events : COADS observations Author(s): Saji, N. H.; Yamagata, T. Source: Journal of Climate Volume: 16 Pages: 2735-2751 Published: 2003 Times Cited: 131 DOI: 10.1175/1520-0442(2003)0162.0.CO;2 added 24-May-10
5.Title: Role of Narrow Mountains in Large Scale Organization of Asian Monsoon Convection Author(s): Xie, S. P.; Xu, H.; Saji, N. H.; et al. Source: Journal of Climate Volume: 19 Pages: 3420-3429 Published: 2006 Times Cited: 108 DOI: 10.1175/JCLI3777.1 added 24-May-10
6.Title: Response of the equatorial Indian Ocean to an unusual wind event during 1994 Author(s): Vinayachandran, P. N.; Saji, N. H.; Yamagata, T. Source: Geophysical Research Letters Volume: 26 Pages: 1613-1616 Published: 1999 Times Cited: 102 DOI: 10.1029/1999GL900179 added 24-May-10
7.Title: Tropical Indian Ocean Variability in the IPCC 20th-century climate simulations Author(s): Saji, N. H.; Xie, S. P.; Yamagata, T. Source: Journal of Climate Volume: 19 Pages: 4397-4417 Published: 2006 Times Cited: 78 DOI: 10.1175/JCLI3847.1 added 24-May-10
8.Title: Comments on "Dipoles, Temperature Gradients, and Tropical Climate Anomalies" Author(s): Yamagata, T.; Behera, S. K.; Rao, S. A.; et al. Source: Bulletin of the American Meteorological Society Volume: 84 Pages: 1418-1422 Published: 2003 Times Cited: 53 DOI: 10.1175/BAMS-84-10-1418 added 24-May-10
9.Title: Comments on "A Cautionary Note on the Interpretation of EOFs" Author(s): Behera, S. K.; Rao, S. A.; Saji, N. H.; et al. Source: Journal of Climate Volume: 16 Pages: 1087-1093 Published: 2003 Times Cited: 42 DOI: 10.1175/1520-0442(2003)0162.0.CO;2 added 24-May-10
10.Title: Satellite observations of intense intraseasonal cooling events in the tropical south Indian Ocean Author(s): Saji, N. H.; Xie, S. P.; Tam, C. Y. Source: Geophysical Research Letters Volume: 33 Published: 2006 Times Cited: 35 DOI: 10.1029/2006GL026525 added 24-May-10
11.Title: Indian Ocean Dipole Mode events and austral surface temperature anomalies Author(s): Saji, N. H.; Ambrizzi, T.; Ferraz, S. E. T. Source: Dynamics of Atmospheres and Oceans Volume: 39 Pages: 87-101 Published: 2005 Times Cited: 33 DOI: 10.1016/j.dynatmoce.2004.10.015 added 24-May-10
12.Title: Processes and boreal summer impacts of the 2004 El Nino Modoki: An AGCM study Author(s): ASHOK, K; IIZUKA, S; RAO, SA; et al. Source: GEOPHYSICAL RESEARCH LETTERS Volume: 36 Published: 2009 Times Cited: 25 DOI: 10.1029/2008GL036313 added 29-Jul-09
13.Title: Mechanisms of South Indian Ocean intraseasonal cooling Author(s): VINAYACHANDRAN, PN; SAJI, NH Source: GEOPHYSICAL RESEARCH LETTERS Volume: 35 Issue: 23 Published: 2008 Times Cited: 21 DOI: 10.1029/2008GL035733 added 28-Jul-09
14.Title: On the impacts of ENSO and Indian Ocean dipole events on sub-regional Indian summer monsoon rainfall Author(s): ASHOK, K; SAJI, NH Source: NATURAL HAZARDS Volume: 42 Issue: 2 Pages: 273-285 Published: AUG 2007 Times Cited: 19 DOI: 10.1007/S11069-006-9091-0 added 28-Jul-09
15.Title: Statistical Downscaling of Precipitation in Korea Using Multimodel Output Variables as Predictors Author(s): Kang, H.; Park, C. K.; Saji, N. H.; et al. Source: Monthly Weather Review Volume: 137 Pages: 1928-1938 Published: 2009 Times Cited: 19 DOI: 10.1175/2008MWR2706.1 added 24-May-10
16.Title: Intercomparison of the seasonalcycle of the tropical surface wind stress in 17 AMIP atmospheric general circulation models Author(s): Saji, N. H.; Goswami, B. N. Source: Climate Dynamics Volume: 13 Pages: 561-585 Published: 1997 Times Cited: 12 DOI: 10.1007/s003820050183 added 24-May-10
17.Title: Hindcast skill and predictability for precipitation and two-meter air temperature anomalies in global circulation models over the Southeast United States Author(s): Stefanova, Lydia; Misra, Vasubandhu; O’Brien, James; et al. Source: Climate Dynamics Pages: 1-13 Published: 2011 Times Cited: 8 DOI: 10.1007/s00382-010-0988-7 / Author-provided URL : 01-Nov-11
18.Title: Evaluation of the Weather Generator CLIGEN with Daily Precipitation Characteristics in Korea Author(s): Min, Y. M.; Kryjov, V.; An, K. H.; et al. Source: Asia-Pacific Journal of Atmospheric Sciences Volume: 47 Pages: 255-263 Published: 2011 Times Cited: 7 DOI: 10.1007/s13143-011-0014-y added 01-Nov-11
19.Title: An improved linear model of tropical surface wind variability Author(s): SAJI, NH; GOSWAMI, BN Source: QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY Volume: 122 Issue: 529 Pages: 23-53 Published: JAN 1996 Times Cited: 6 DOI: 10.1256/smsqj.52902 added 29-Jul-09
21.Title: Nonlinear, Intraseasonal Phases of the East Asian Summer Monsoon: Extraction and Analysis Using Self-Organizing Maps Author(s): Chu, Jung-Eun; Hameed, Saji N.; Ha, Kyung-Ja Source: Journal of Climate Volume: 25 Issue: 20 Pages: 6975-6988 Published: 2012/10/01 Times Cited: 6 DOI: 10.1175/JCLI-D-11-00512.1 / Author-provided URL : 04-Apr-13
22.Title: What caused the cool summer over northern Central Asia, East Asia and central North America during 2009? Author(s): Kyung-Ja Ha and Jung-Eun Chu and June-Yi Lee and Bin Wang and Saji, N. Hameed and Masahiro Watanabe Source: Environmental Research Letters Volume: 7 Issue: 4 Pages: 044015 Published: 2012 Author-provided URL : 30-Oct-12
23.Title: Accelerating Lagrangian Particle Dispersion in the Atmosphere with OpenCL Across Multiple Platforms Author(s): Harvey, Paul; Hameed, Saji; Vanderbauwhede, Wim Conference: Proceedings of the International Workshop on OpenCL 2013 & 2014 Pages: 1-8 Year: 2014 Author-provided URL : 08-Mar-15
24.Title: The role of tropical Atlantic SST anomalies in modulating western North Pacific tropical cyclone genesis Author(s): Huo, Liwei; Guo, P.; Saji, N. Hameed; et al. Source: Geophysical Research Letters Volume: 42 Published: 2015 DOI: 10.1002/2015GL063184