New research indicates “that any particular place on the globe gets half its annual rainfall–on average–in just 12 days” out of the year. Which particular days varies, of course, from “place to place and season to season … but the pattern holds worldwide.”
In the study, daily rainfall from 1999 to 2014 at 185 sites located worldwide was analyzed. The research also used 36 climate models to “assess how rainfall trends might change in the future” especially between the years 2085 and 2100.
Based on the continued inaction by many today, it will very likely be an even warmer world by 2100 with the atmospheric concentrations of carbon dioxide (CO2) likely doubling or more from today’s levels. Under that scenario–between 2085 and 2100–the prediction is that “any particular locale can expect half a year’s rainfall to occur in just 11 days” (even faster than today). Plus, future rainfall is likely to be even more uneven than rainfall today–more periods of little or no rain (more drought) interspersed with a few instances of even more extreme rain leading to flooding, mudslides, and more. Half of the increase in rainfall will happen in the wettest 6 days each year. Today and especially by 2085 to 2100, “society needs to take measures to deal with little change most of the time and a handful of events with much more rain.”
All of this makes sense–a warmer world holds more moisture (water vapor) in the atmosphere and, thus, our extreme rainfall events of today will likely become “even more extreme.”
Read the article (Sid Perkins, Science, November 15, 2018).