Research ArticleCLIMATE MODELING

Global warming without global mean precipitation increase?

Science Advances  24 Jun 2016:
Vol. 2, no. 6, e1501572
DOI: 10.1126/sciadv.1501572

You are currently viewing the abstract.

View Full Text

Abstract

Global climate models simulate a robust increase of global mean precipitation of about 1.5 to 2% per kelvin surface warming in response to greenhouse gas (GHG) forcing. Here, it is shown that the sensitivity to aerosol cooling is robust as well, albeit roughly twice as large. This larger sensitivity is consistent with energy budget arguments. At the same time, it is still considerably lower than the 6.5 to 7% K−1 decrease of the water vapor concentration with cooling from anthropogenic aerosol because the water vapor radiative feedback lowers the hydrological sensitivity to anthropogenic forcings. When GHG and aerosol forcings are combined, the climate models with a realistic 20th century warming indicate that the global mean precipitation increase due to GHG warming has, until recently, been completely masked by aerosol drying. This explains the apparent lack of sensitivity of the global mean precipitation to the net global warming recently found in observations. As the importance of GHG warming increases in the future, a clear signal will emerge.

Keywords
  • Climate modeling
  • global warming
  • global mean precipitation
  • hydrological sensitivity
  • aerosol
  • CMIP5
  • anthropogenic climate change

This is an open-access article distributed under the terms of the Creative Commons Attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

View Full Text

More Like This