Article

Influence of savanna fire on Australian monsoon season precipitation and circulation as simulated using a distributed computing environment

University of Vic, Vic, Catalonia, Spain
Geophysical Research Letters (Impact Factor: 4.2). 10/2007; 34(20):20801-20801. DOI: 10.1029/2007gl030879

ABSTRACT

Fires in the Australian savanna have been hypothesized to affect monsoon evolution, but the hypothesis is controversial and the effects have not been quantified. A distributed computing approach allows the development of a challenging experimental design that permits simultaneous variation of all fire attributes. The climate model simulations are distributed around multiple independent computer clusters in six countries, an approach that has potential for a range of other large simulation applications in the earth sciences. The experiment clarifies that savanna burning can shape the monsoon through two mechanisms. Boundary-layer circulation and large-scale convergence is intensified monotonically through increasing fire intensity and area burned. However, thresholds of fire timing and area are evident in the consequent influence on monsoon rainfall. In the optimal band of late, high intensity fires with a somewhat limited extent, it is possible for the wet season to be significantly enhanced.

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    • "In addition, anthropogenic changes in land use can lower water tables and reduce water available to vegetation, which, in turn, can affect ecosystem exchange of sensible and latent energy (Nichols 1994, Elmore et al. 2003, Cooper et al. 2006). Hence, fluxes from land surfaces and vegetation can profoundly impact atmospheric circulation and precipitation patterns on multiple scales (Shukla and Mintz 1982, Beringer et al. 2003, Loescher et al. 2006a, Lynch et al. 2007), creating possible feedbacks exacerbating water limitation. Changes in vegetation and land cover due to altered water availability could also have further effects on energy partitioning by altering fire frequency and intensity in savanna ecosys- tems. "

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    • "In addition, anthropogenic changes in land use can lower water tables and reduce water available to vegetation, which, in turn, can affect ecosystem exchange of sensible and latent energy (Nichols 1994, Elmore et al. 2003, Cooper et al. 2006). Hence, fluxes from land surfaces and vegetation can profoundly impact atmospheric circulation and precipitation patterns on multiple scales (Shukla and Mintz 1982, Beringer et al. 2003, Loescher et al. 2006a, Lynch et al. 2007), creating possible feedbacks exacerbating water limitation. Changes in vegetation and land cover due to altered water availability could also have further effects on energy partitioning by altering fire frequency and intensity in savanna ecosys- tems. "
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