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Who can tell what the future will be like?

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NASA scientists have combined data from several climate models,

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used by the UN Intergovernmental Panel on Climate Change, to show how patterns of temperature

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and precipitation could change through the end of the 21st century.

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This visualization shows the expected

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changes in temperature and precipitation we might see,

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compared to the average levels of the late 20th century.

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The largest temperature increases are seen in the northern hemisphere.

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Across North America, areas that typically have snow, such as the Rocky Mountains

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and northern Canada, will see the earliest and largest

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temperature rise. The warming temperatures will eliminate the

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reflective and cooling effect of the white snow cover.

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This reduction in albedo is the reason why the Arctic region shows such dramatic warming,

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as the polar sea ice melts and the darker ocean water absorbs

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energy from the sun.

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In turn, the warmer water accelerates the melting of the sea ice.

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All around the globe, the land areas show a greater increase in temperature

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than the surrounding ocean waters.

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Evaporation of the water helps to keep the ocean surface cool,

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and the deep depths of the ocean have a large capacity to absorb energy before heating up.

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Off the coast of South America stretches an unusually warm patch of the Pacific Ocean.

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A cyclical occurrence, known as El Niño, causes more precipitation

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in that area of the Pacific, and affects the climate throughout the region.

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And we can see that happen in this visualization

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of changes in precipitation. Models project warmer waters

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and increased precipitation to stretch across the Pacific Ocean

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to Indonesia as the century progresses.

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The monsoons over the Indian subcontinent will bring increased precipitation

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over a wider area, and eastern Africa

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and the savannas of the Sahel, could see precipitation increases up to 100%.

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At the same time, the Mediterranean will experience the opposite,

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a decrease over 40%.

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In general, the mid-latitude and sub-tropical dry regions are projected to see

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less precipitation, while the mid-latitude wet regions could see more precipitation.

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The poles and high latitudes are expected to also have increased precipitation.

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For North America, the models indicate more precipitation in the north,

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and less in the south.

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