The World Gets Half of Its Annual Rainfall in Just 12 Days

A new study shows that any particular place on the planet gets half its annual rainfall in just 12 days on average.

Researchers examined daily rainfall data from 185 sites from 1999 through 2014. That period was enough time to capture variations in rainfall caused by El Niño and other short-term climate cycles.

The wettest day on average at each site got a full month’s worth of rain and half the site’s got all of their precipitation over just 12 days, researchers reported in Geophysical Research Letters. The specific days that are the wettest is different from place to place and season to season, but the pattern holds worldwide.

Researchers used 36 different climate models to assess how rainfall trends may change. They looked at estimates for daily rainfall for 2085 through 2100 for a scenario where the concentration of carbon dioxide rises to 936 parts per million in the year 2100. In that scenario the air will be able hold more water, and extreme rainfall will become more extreme. In the last decade of this century, any particular location can expect half of their annual rainfall to occur in just 11 days.



Photo: “Rain Storm Colorado Springs Colorado” by David is licensed under CC BY 2.0