Fire in the Amazon rainforest has consequences that reach far beyond the place on the ground where the fire occurs. In addition to the transformation of the landscape, the smoke from fires changes clouds and rainfall. Smoke "chokes off" cloud formation (see “Clouds Are Cooler Than Smoke” in the Features section), and while the smoke provides some cooling by intercepting incoming solar radiation, the effect is not as great as the cooling provided by clouds. So the net result of smoke replacing clouds is warming. In addition, research published in the journal Science in Febraury 2004 demonstrated that smoke suppresses Amazon rainfall while increasing the intensity of the rain that does fall (see “Documenting a Paradox: Smoke Decreases Rainfall but Ultimately Increases Its Intensity” in the Media Alerts Archive.)
This image shows fires burning across the southern Amazon, west of the Xingu River watershed, which is almost completely hidden by thick smoke at upper right. At lower left is Lake Titicaca. The image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite on August 19, 2004. Active fire locations are marked in red.