Wednesday, 12 February 2003: 8:30 AM
The Effects of Amazonian, African and Southeast Asian Deforestation
We show that large-scale vegetation changes have a significant effect on the local hydroclimate, and also on the hydroclimate of areas remote from the location of the surface change. We have simulated with the NASA - Goddard Institute for Space Studies GCM the removal of tropical rainforest: first individually over the Amazon, Africa and Southeast Asia, and then with all three areas deforested in the same simulation. In each area, we have noted a strong local effect reflected through reductions in precipitation, evaporation, cloudiness, and higher surface temperatures. The local changes in each area are also responsible for statistically-significant precipitation reductions in remote areas of the world, some quite distant from the deforested areas. We examine in detail the alterations in surface radiation budget responsible for the local changes, and explore the teleconnections that trigger the remote changes.