NASA: Rain falls more often during the week than weekends
February 4, 2008
Storms in the southeastern United States generate more rainfall during the work week than on weekends, report NASA scientists. The pattern can be attributed to lower atmospheric pollution from humans on Fridays, Saturdays and Sundays. Atmospheric particulates have been linked to rainfall.
Analyzing seven years of data from NASA’s TRMM satellite and the Environmental Protection Agency, researchers led by Thomas Bell, an atmospheric scientist at NASA’s Goddard Space Flight Center, that, on average, it rains more between Tuesday and Thursday than from Saturday through Monday. Average afternoon rainfall peaks on Tuesday, with 1.8 times more rainfall than on Saturday, which experiences the least amount of afternoon rain. The pattern matches that of pollution levels.
“If two things happen at the same time, it doesn’t mean one caused the other,” Bell says. “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.”
The research is published in the current Journal of Geophysical Research – Atmospheres.
CITATION: Bell, T. L., D. Rosenfeld, K.-M. Kim, J.-M. Yoo, M.-I. Lee, and M. Hahnenberger (2008), Midweek increase in U.S. summer rain and storm heights suggests air pollution invigorates rainstorms, J. Geophys. Res., 113, D02209,