A Quick Look
Voices from Brazil:
"Without the forest peoples, the traditional populations, without the Quilombolas, without the river dwellers, the fishermen, without the women coconut breakers, without the indigenous people, there won’t be forest. Forests only exist because these populations have protected them. Where there was no population, forests are gone; wherever these groups remain, forests will too. Our people need the forest for transportation, housing, health, and even for music. Forest is very important for us. We could not live without the forest."
Rubens Gomes, Amazon Working Group (Grupo de Trabalho Amazônico, GTA)
So what do scientists believe the future holds? Global average temperatures are expected to increase by about 1-7°C by the end of the century. In South America, Amazonia is likely to see the greatest warming.
Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Figure 10.8, Cambridge University Press
As a result of this warming and lower humidity, inter-tropical glaciers are very likely to disappear in the next 15 years. This will seriously affect water supplies for the region.
Because a warmer planet will boost evaporation and change atmospheric moisture circulation, many dry areas will become drier and wet areas wetter. Northeast Brazil, for example, will likely dry and see a shift from semi-arid to arid or desert-like vegetation. As a result, groundwater recharge there is projected to decrease by more than 70%.
Projections of relative changes in runoff by end of 21st century.
Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II, and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Figure 3.5, Geneva, Switzerland.
Warming of 2°C and decreases in soil water would lead to replacement of tropical forest by savannas in eastern Amazonia and central and southern Mexico, according to the IPCC, a scientific, intergovernmental body established by the United Nations to study climate change.
The oceans will continue rising in the coming century. The IPCC’s best estimates range from a few centimeters to about half a meter by 2100. In low-lying areas, this could inundate land relatively far from current shores.
The IPCC’s projections of sea level rise are at best a rough estimate, however. The complete loss of either the West Antarctic Ice Sheet or the Greenland Ice Sheet could eventually raise sea levels on the order of 6 meters.
To see what scientists project is in store as a result of climate change for some specific parts of South America, examine this map. We will explore many of these topics in detail in the next section.
Climate Change 2007: Impacts, Adaption, and Vulnerability. Working Group II Contribution to the Fourth Assessment Report of the Intergovernmental. Panel on Climate Change. Figure 13.5, Cambridge University Press.