Modern and Future Climate

The Climate Science Group strives to solve problems in climate on timescales from seasonal to Quaternary and beyond. We use models representing the ocean, the atmosphere, the cryosphere and the land surface, ranging from simple to complex. In addition to analyses of data from recent decades, we develop techniques to extract as much as possible from the inaccurate and sparse data of the past.
Much of our work, often in collaboration with the International Research Institute located at Lamont, has been on understanding and predicting seasonal to interannual climate variations, especially El Niño and the North Atlantic Oscillation, and on the impacts of such variations on agriculture and health. Our recent focus is on accounting for the startlingly abrupt changes apparent in the paleoclimate record. Could such changes occur in the near future? Our investigations of the past and the future rely heavily on our knowledge of modern climate dynamics.

Douglas G. Martinson
Personal Information
Douglas
G.
Martinson
Lamont Research Professor
Lamont-Doherty Earth Observatory
Ocean and Climate Physics
Adjunct Professor
Earth and Environmental Sciences
Contact Information
105 Oceanography
61 Route 9W - PO Box 1000
Palisades
NY
10964-8000
US
(845) 365-8830

Fax: 

(845) 365-8157

Fields of interest: 

Oceans and their role in climate; onset and termination of ice ages.

I wanted to be an oceanographer ever since my first visit to the ocean near Carmel
The research includes both modeling and observational studies in polar regions

Education
Ph.D.
Columbia
1982
Master of Arts
Columbia
1979
Bachelor of Science
Cal State
1976
Adam H. Sobel
Personal Information
Adam
H.
Sobel
Professor
Earth and Environmental Sciences
Ocean and Climate Physics
Ocean and Climate Physics
Professor
Applied Physics and Applied Mathematics
Professor
Lamont-Doherty Earth Observatory
Contact Information
206C Oceanography
61 Route 9W - PO Box 1000
Palisades
NY
10964-8000
US
(845) 365-8527

Fax: 

(845) 365-8157

Fields of interest: 

Atmospheric and climate dynamics, tropical meteorology.

In the extratropical latitudes (where, for example, Columbia University is located) we have a fairly good understanding of the basic dynamical processes that control the atmosphere's behavior. This understanding has two manifestations. With sophisticated numerical models, we can predict the extratropical weather fairly well, up to a week ahead or so. We also have much simpler mathematical models which, though not accurate enough to produce good weather forecasts, capture the basic dynamics of the atmosphere and can at least qualitatively simulate the important phenomena such as winter storms, fronts, waves in the jet stream, etc. These simpler models are derived as approximations to the full equations of atmospheric motion and energy. They form the core of our understanding and guide us as we analyze both observations and numerical simulations of the extratropical atmosphere. 

The atmosphere behaves differently in the tropics than in the extratropics, and is less well understood. Weather forecasts are considerably less accurate in the tropics, and many of the largest uncertainties in our simulations of the global climate are related to gaps in our understanding of tropical atmospheric processes. In particular, we do not understand, in a wide range of circumstances, what controls where and when rain falls in the tropics. This lack of understanding and predictive capability is expressed by our lack of simple mathematical models for the tropics that combine economy and correctness as successfully as the simple extratropical models do. 

My research efforts are focused on improving our understanding of tropical dynamics.  I focus to a large extent on what controls rainfall patterns and their variability on time scales of days to decades.  My associates and I use mathematical models of varying degrees of complexity for this purpose.  Some can be solved with pencil and paper, and some (more typically) require powerful computers.  We also analyze observational data, which is important to keep a theoretical and modeling research program grounded in reality.

Some of my projects include:

  • Madden-Julian Oscillation (including DYNAMO field program, see maddenjulianconversation.blogspot.com)
  • Tropical cyclones and climate
  • African drought
  • Circulation and seasonal cycle changes under global warming
  • Atmospheric water vapor
Education
PhD
Massachusetts Institute of Technology
02/1998
Selected Publications:
Rain on small tropical islands, Sobel, A. H.; Burleyson, C. D.; Yuter, S. E. Journal of Geophysical Research, Volume: 116 (2011) 10.1029/2010JD014695
Response of convection to relative sea surface temperature: Cloud-resolving simulations in two and three dimensions, Wang., S.; Sobel, A. H. Journal of Geophysical Research, Issue: 116 (2011) 10.1029/2010JD015347
A systematic relationship between intraseasonal variability and mean state bias in AGCM simulations, Kim, D.; Sobel, A. H.; Maloney, E. D.; Frierson, D. M. W.; Kang, I.-S. Journal of Climate, Volume: 24 p.: 5506-5520 (2011)
Delayed seasonal cycle and African monsoon in a warmer climate, Biasutti, M; Sobel, A H Geophysical Research Letters, Volume: 36 p.: L23707 (2009)
A global perspective on African climate, Giannini, A.; Biasutti, M.; Held, I. M.; Sobel, A. H. Climatic Change Oct, Volume: 90, Issue: 4 p.: 359-383 (2008) DOI 10.1007/s10584-008-9396-y
The role of surface fluxes in tropical intraseasonal oscillations, Sobel, A. H.; Maloney, E. D.; Bellon, G.; Frierson, D. M. W. Nature Geoscience, Volume: 1 p.: 653-657 (2008)
Use of a genesis potential index to diagnose ENSO effects on tropical cyclone genesis, Camargo, S.J.; Emanuel, K.A.; Sobel, A.H. Journal of Climate, Volume: 20 p.: 4819-4834 (2007)
Influence of western North Pacific tropical cyclones on their large-scale environment, Sobel, A. H.; Camargo, S. J. Journal of the Atmospheric Sciences Sep, Volume: 62, Issue: 9 p.: 3396-3407 (2005)
Western North Pacific tropical cyclone intensity and ENSO, Camargo, S.J.; Sobel, A.H. Journal of Climate Aug 1, Volume: 18, Issue: 15 p.: 2996-3006 (2005)
A simple time-dependent model of SST hot spots, Sobel, A. H.; Gildor, H. Journal of Climate Dec, Volume: 16, Issue: 23 p.: 3978-3992 (2003)
The Hadley circulation and the weak temperature gradient approximation, Polvani, L. M.; Sobel, A. H. Journal of the Atmospheric Sciences May 15, Volume: 59, Issue: 10 p.: 1744-1752 (2002)
The weak temperature gradient approximation and balanced tropical moisture waves, Sobel, A. H.; Nilsson, J.; Polvani, L. M. Journal of the Atmospheric Sciences, Volume: 58, Issue: 23 p.: 3650-3665 (2001)

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