Regional dry-season climate changes due to three decades of Amazonian deforestation
A substantial portion of the clouds and precipitation in the Amazon rainforest are generated locally by the forest itself, making it a unique biome capable of self-supporting its ecosystems to some extent. But about 20% of this rainforest has already been cleared which can cause modifications to clouds and precipitation crucial to the forest and the ecosystems dependent on it. This study shows that contemporary deforestation, occurring at scales of a few hundreds of kilometers, has triggered a precipitation redistribution over the forest clearings resulting in a ~25% increase in precipitation in one half of the deforested domain and a ~25% decrease in another. Such a redistribution of precipitation can have contrasting consequences for the vegetation in the two halves of the deforested area and the surrounding forest, giving context to rethink the consequences of future Amazonian deforestation.
Figure 5 - Transition in the dominant convective regime with increasing scales of deforestation. a, In the early period, convection over the deforested region is enhanced by thermal triggering alone. b, In the present-day period, horizontal variations in surface roughness result in a suppression of convection in the upwind sector and enhancement of convection in the downwind sector. Republished from DOI:10.1038/nclimate3226.
Khanna, J., D., Medvigy, S. Fueglistaler and R. Walko. Regional dry-season climate changes due to three decades of Amazonian deforestation. Nature Clim. Change, Online: 2017/02/20 DOI:10.1038/nclimate3226