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Human-induced changes in the 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...
Autores principales: | , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American Association for the Advancement of Science
2017
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5451196/ https://www.ncbi.nlm.nih.gov/pubmed/28580418 http://dx.doi.org/10.1126/sciadv.1600871 |
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author | Putnam, Aaron E. Broecker, Wallace S. |
author_facet | Putnam, Aaron E. Broecker, Wallace S. |
author_sort | Putnam, Aaron E. |
collection | PubMed |
description | 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. |
format | Online Article Text |
id | pubmed-5451196 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2017 |
publisher | American Association for the Advancement of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-54511962017-06-02 Human-induced changes in the distribution of rainfall Putnam, Aaron E. Broecker, Wallace S. Sci Adv Research Articles 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. American Association for the Advancement of Science 2017-05-31 /pmc/articles/PMC5451196/ /pubmed/28580418 http://dx.doi.org/10.1126/sciadv.1600871 Text en Copyright © 2017, The Authors http://creativecommons.org/licenses/by-nc/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license (http://creativecommons.org/licenses/by-nc/4.0/) , which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited. |
spellingShingle | Research Articles Putnam, Aaron E. Broecker, Wallace S. Human-induced changes in the distribution of rainfall |
title | Human-induced changes in the distribution of rainfall |
title_full | Human-induced changes in the distribution of rainfall |
title_fullStr | Human-induced changes in the distribution of rainfall |
title_full_unstemmed | Human-induced changes in the distribution of rainfall |
title_short | Human-induced changes in the distribution of rainfall |
title_sort | human-induced changes in the distribution of rainfall |
topic | Research Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5451196/ https://www.ncbi.nlm.nih.gov/pubmed/28580418 http://dx.doi.org/10.1126/sciadv.1600871 |
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