the role of antarctica in understanding the earth’s atmosphere and climate
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The Role of Antarctica in Understanding the Earth’s Atmosphere and Climate. Richard Brandt University of Washington and Paul Smith’s College. National Science Foundation Office of Polar Programs. Italian National Research Program in Antarctica. Institut Polaire Français. James Elkens - PowerPoint PPT PresentationTRANSCRIPT
The Role of Antarctica in Understanding the Earth’s Atmosphere and Climate
Richard Brandt
University of Washingtonand
Paul Smith’s College
Institut Polaire Français National Science FoundationOffice of Polar Programs
Italian National Research Program in Antarctica
James ElkensNOAA-CMDL2001
http://books.nap.edu/catalog/10139.html
What are the atmospheric gasses that cause the greenhouse effect?
Not the major gasses:N2 78%O2 21%Ar 1%
On earth (unlike venus and mars) it is the minor gasses that are
responsible for the greenhouse:H2OCO2
O3
CH4
N2O
Determining Earth’s past climate 1. Human record (only~2000 years)
2. Ice cores in Antarctica and Greenland. (up to 475,000 years ago)
3. Tree ring analysis, extent of pollen deposition(up to millions of years)
4. Ocean sediments and geochemistry(over a half billion years)
The Dome C δD record resembles Vostok and Dome F records over their common parts
EPICA Community paper, Nature, 2004
Jones, P.D. and Moberg, A., 2003: Hemispheric and large-scale surface air temperature variations: An extensive revision and an update to 2001. Journal of Climate, 16, 206-223.
T.P. Barnett, D.W. Pierce, R. Schnur, Science 292, 270 (2001)
1. Feedbacks: two positive examples CO2 insulation SST evaporation H2O insulation SST
CO2 insulation SST sea ice extent albedo absorbed sunlight SST
Why is predicting our future climate so difficult?
2. Feedbacks: two negative examples CO2 insulation SST evaporation H2O clouds SST
CO2 insulation SST phytoplankton DMS Cloud condensation nucleii clouds SST
Why is predicting our future climate so difficult?
1. Detailing climate feedbacks properly to get the correct climate amplification (example is ice-albedo feedback)
2. Improving our understanding of albedo, temperature, water vapor, cloud cover, atmospheric dynamics of the less populated parts of earth, especially the polar regions. (Few or no weather and climate records) 3. Climate models are computationally intensive and there are complexities due to such a highly nonlinear system (for example atmospheric turbulence which is chaotic). We are limited by our computing power for regional scale modeling.
Why is predicting our future climate so difficult?