Principal
Investigator: Dr. Prince
A
key uncertainty in the Earth System is the response of the vegetation-climate
system to seasonal and interannual climate variability.
In this project models have been developed and tested that are capable of
reasonable predictions of actual, as opposed to equilibrial, land surface and
atmospheric conditions. In particular, major changes have been accomplished in the
accuracy of the measurement of land surface biophysical variables.
Three models have been adapted, modified or created to make use of the
new data sources, including two biogeochemical models of different types and a
SVAT model. Numerical experiments
have been conducted to test the effects of seasonal and interannual variability
in the land surface boundary conditions on the climate and its variability, also
the feedback effects of climate variability on vegetation.
This research has prepared the way to study the nature, causes and
implications of regional-to-global scale vegetation changes, emphasizing the
responses to transient climate anomalies, in an integrated, observational and
process-modeling program.
Further,
the project is exploring the implications of the observed and modeled vegetation
dynamics on climate using a spatial run of the SVAT model for Africa and, if
time permits, a coupled general circulation model (GCM) run.
The existing results will be prepared for publication.
Special attention is being paid to several regions where the climate is
most sensitive to the land surface forcing, including the impact of atmospheric
circulation changes on southern central Africa (current focus of the SAFARI 2000
program). The use of the
observational satellite data record ensures that plausible scenarios for
regional vegetation-climate changes are addressed and that they are
geographically realistic. We will
continue to explore the dynamics of regional-global vegetation changes in
response to climate changes using the 20-year archive of NOAA Advanced Very High
Resolution Radiometer data and other archival data.