Greenhouse Warming Linked to Shifts in Rainfall

The models project for every 1 degree Fahrenheit of carbon dioxide-induced warming, heavy rainfall will increase globally by 3.9 percent and light rain will increase globally by 1 percent. However, total global rainfall is not projected to change much because moderate rainfall will decrease globally by 1.4 percent.

This visualization shows an average rainfall month for June,July, and August. The movie will display areas with no rain (brown), moderate rain (tan), and heavy rain (blue). Very Heavy rainfall (dark blue) is defined as months that receive an average of 0.95 of an inch of rain per day (24 mm/day) every day for the months of June, July, and August. Heavy rainfall is defined as months that receive an average of more than about 0.35 of an inch per day (9 mm/day). Light rain is defined as months that receive an average of less than 0.01 of an inch per day. Moderate rainfall is defined as months that receive an average of between about 0.04 to 0.09 of an inch per day.