Human-induced changes in the distribution of rainfall
| Autor: | Aaron E. Putnam, Wallace S. Broecker |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
010504 meteorology & atmospheric sciences
Rain storm tracks global warming 010502 geochemistry & geophysics Atmospheric sciences 01 natural sciences Physics::Geophysics hydroclimate Paleoclimatology Humans Precipitation Southern Hemisphere Astrophysics::Galaxy Astrophysics Physics::Atmospheric and Oceanic Physics Research Articles ITCZ 0105 earth and related environmental sciences Climatology Bølling-Allerød Tropical Climate Multidisciplinary Global warming Northern Hemisphere SciAdv r-articles Last Glacial Maximum Models Theoretical interhemispheric temperature contrast thermal equator Middle latitudes Little Ice Age Environmental science Astrophysics::Earth and Planetary Astrophysics Research Article Thermal equator |
| Zdroj: | Science Advances |
| ISSN: | 2375-2548 |
| DOI: | 10.1126/sciadv.1600871 |
| Popis: | As the planet warms, differential heating between the hemispheres will affect the global distribution of rainfall. A likely consequence of global warming will be the redistribution of Earth’s rain belts, affecting water availability for many of Earth’s inhabitants. We consider three ways in which planetary warming might influence the global distribution of precipitation. The first possibility is that rainfall in the tropics will increase and that the subtropics and mid-latitudes will become more arid. A second possibility is that Earth’s thermal equator, around which the planet’s rain belts and dry zones are organized, will migrate northward. This northward shift will be a consequence of the Northern Hemisphere, with its large continental area, warming faster than the Southern Hemisphere, with its large oceanic area. A third possibility is that both of these scenarios will play out simultaneously. We review paleoclimate evidence suggesting that (i) the middle latitudes were wetter during the last glacial maximum, (ii) a northward shift of the thermal equator attended the abrupt Bølling-Allerød climatic transition ~14.6 thousand years ago, and (iii) a southward shift occurred during the more recent Little Ice Age. We also inspect trends in seasonal surface heating between the hemispheres over the past several decades. From these clues, we predict that there will be a seasonally dependent response in rainfall patterns to global warming. During boreal summer, in which the rate of recent warming has been relatively uniform between the hemispheres, wet areas will get wetter and dry regions will become drier. During boreal winter, rain belts and drylands will expand northward in response to differential heating between the hemispheres. |
| Databáze: | OpenAIRE |
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