Thursday, 13 February 2003: 11:30 AM
Impact of Deforestation on Precipitation
Wholesale destruction of tropical forests on continental scales has been shown
in numerical experiments to produce large changes in regional climate, e.g., a
decrease in precipitation. Other work has shown, however, that mesoscale
landscape heterogeneity, as created, for example, by partial deforestation,
can induce atmospheric circulations that can alter the intensity and spatial
distribution of the pre-existing pattern of precipitation, sometimes enhancing
total rainfall in a given region. The interaction between large-scale and
mesoscale effects and their net impact on total rainfall for a given amount of
deforestation remains an open question.
Here we use high-resolution numerical experiments with the Regional
Atmospheric Modeling System (RAMS) to examine the dependence of
monthly-to-seasonally averaged precipitation on two factors: (i) the extent of
deforestation; and (ii) the degree of forest fragmentation (patchiness). We
discuss the relative roles of these two factors in determining total rainfall.
Supplementary URL: