NASA research shows pollution increases rainfall

Research by NASA has found that rainy summer days in southeastern U.S. states are more common in the middle of the week, when pollution from human activity also reaches its highest levels.

Furthermore, the research found that midweek storms tend to cover a larger area and have a higher level of rainfall than their weekend counterparts.

Organising days into weeks is a human convention, so there is no natural explanation for why this occurs. As such, NASA says that the mostly likely reason for the rainfall patterns is human activity.

Dr. Thomas Bell, an atmospheric scientist at the Goddard Space Flight Centre, says: “It’s eerie to think that we’re affecting the weather. It appears that we’re making storms more violent.”

The team of scientists at NASA identified the trend by looking at data from NASA’s Tropical Rainfall Measuring Mission satellite. The satellite data was used to estimate daily summertime rainfall averages from 1998 to 2005 across the whole of southeastern U.S.A.

To see if pollution from human activity was the cause of the discrepancy in measurements, the team also analysed Environmental Protection Agency data on the concentration of particulate matter. This data revealed that pollution tended to peak midweek, echoing the trend in the rainfall data.

Dr. Bell concluded: “If two things happen at the same time, it doesn’t mean one caused the other.

“But it’s well known that particulate matter has the potential to affect how clouds behave, and this kind of evidence makes the argument stronger for a link between pollution and heavier rainfall.”