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.
Off the coast of South America stretches an unusually warm patch of the Pacific Ocean.
A cyclical occurrence, 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.