Simulated response of the atmosphere-ocean system to deforestation in the Indonesian Archipelago

Abstract

The climatic effects of large-scale deforestation in the Indonesian Archipelago are investigated using a fully coupled atmosphere-ocean model -- the Fast Ocean Atmosphere Model (FOAM). Extremely rapid rates of deforestation across the Archipelago motivate this study. We compare two simulations (one with fixed ocean temperatures, another where the ocean responds to changing atmospheric conditions), to investigate the potential for oceanic feedbacks on deforestation-induced climate change. With fixed sea surface temperatures, evaporation decreases over land but increases over the surrounding oceans where the wind speeds increase. Regional deep convection is enhanced and precipitation increases over the islands. With an interactive ocean the initial decrease in evaporation over the deforested land reduces convergence and increases the easterlies in the Bay of Bengal. More intense equatorial upwelling cools the surface temperatures over that region and reduces ocean evaporation. Regional convection is less intense and precipitation drops by 9% over deforested land.