Paleoclimates of Amazonia: An ice-age view

A growing body of evidence points to climatic complexity during the Ice-Ages. Amazonia does not respond uniformly to modern climatic forcing, and the same was true of the past. Although some climatic forcings were probably expressed everywhere, they were manifested differently. Consequently, climate change varied spatially and temporally between reions within Amazonia. We suggest the role of evaporation over the northern tropical Atlantic Ocean and the resulting entrained moisture of the South American Low Level Jet was strong during the Pleistocene. Locations directly influenced by this jet appear to show coherent patterns of climate change, while locations outside of its path are possible more strongly influenced by other factors, such as the migration of the intertropical convergence zone. The forests of the Amazon Bsin were modfied by both drought and cooling at millennial scales, but the concept of forest contraction due to prolonged aridity is not supported.