Who can tell what the future will be like? NASA scientists have combined data from several climate models, used by the UN Intergovernmental Panel on Climate Change to show how patterns of temperature and precipitation could change through the end of the 21st century This visualization shows the expected changes in temperature and precipitation we might see, compared to the average levels of the late 20th century. The largest temperature increases are seen in the northern hemisphere. Across North America, areas that typically have snow, such as the Rocky Mountains and northern Canada, will see the earliest and largest temperature rise. The warming temperatures will eliminate the reflective and cooling effect of the white snow cover. This reduction in albedo is the reason why the Arctic region shows such dramatic warming, as the polar sea ice melts and the darker ocean water absorbs energy from the sun. In turn, the warmer water accelerates the melting of the sea ice.
All around the globe, the land areas show a greater increase in temperature than the surrounding ocean waters. Evaporation of the water helps to keep the ocean surface cool, and the deep depths of the ocean have a large capacity to absorb energy before heating up. Of the coast of South America stretches an unusually warm patch of the Pacific Ocean. A cyclical occurence, known as El Niño, causes more precipitation in that area of the Pacific, and affects the climate throughout the region. And we can see that happen in this visualization of changes in precipitation. Models project warmer waters and increased precipitation to stretch across the Pacific Ocean to Indonesia as the century progresses. The monsoons over the Indian subcontinent will bring increased precipitation over a wider area, and eastern Africa and the savannas of the Sahel, could see precipitation increases up to 100%.
At the same time, the Mediterranean will experience the opposite, a decrease over 40%. In general, the mid-latitude and sub-tropical dry regions are projected to see less precipitation, while the mid-latitude wet regions could see more precipitation. The poles and high latitudes are expected to also have increased precipitation. For North America, the models indicate more precipitation in the north, and less in the south. .