Assistant Professor Dr. Scott Spak co-authored a paper, “Central American biomass burning smoke can increase tornado severity in the U.S.” recently published in Geophysical Research Letters, examining the effects of smoke from agricultural land-clearing fires in Central America on the 27 April 2011 historical tornado outbreak across the Southeast. The team of researchers from the University of Iowa, University of Wisconsin-Madison, NOAA, and NASA found that adding smoke to an environment already conducive to severe storms can increase the likelihood of significant tornadoes. The findings were reported on the NBC Nightly News and covered by CBS News, National Geographic, Science, Nature, and USA Today.

The satellite image for April 27, 2011 shows the southeastern United States, Central America and the Gulf of Mexico—along with tornado tracks (red solid lines, with the thickest indicating a magnitude 5 tornado, descending to magnitude 1 for the thinnest—for the period April 26-28, 2011. Yellow markers indicate fires, and an iridescent overlay shows particulate matter in the air, with red showing highest amount and purple the lowest. Imagery courtesy of Brad Pierce, NOAA Satellite and Information Service Center for Satellite Applications and Research.