Prof. Robert J. (Jeff) Trapp is a wonderful person and a great scientist. Along with his groundbreaking research that I highlight below, I want to start by acknowledging the strong diversity of his graduate program where Jeff has been a leader in bringing more women and minority students into careers in science. In his research, Jeff has made major contributions to the fundamental understanding of a remarkable range of severe weather hazards, particularly tornadoes and damaging thunderstorm winds. Using innovative approaches, he has also discovered patterns in the climatological/statistical occurrence of tornadoes (and hail), and he has used these risk assessments to motivate efforts to predict tornado activity over subseasonal to seasonal (S2S) timescales. In addition, he pioneered the study of severe-thunderstorm frequency and intensity in response to climate change. Jeff’s early work on modes of tornadogenesis helped reconcile a long-standing conflict between observations and theory. His work also provided new insights into the rotational dynamics of quasi-linear convective systems (QLCSs), and then he and colleagues discovered that nearly half of all tornadoes in the U.S. Midwest and Southeast are associated with QLCSs. Jeff is also known for his research on the mechanisms of nontornadic wind damage in thunderstorm systems; for example, Jeff and his collaborators discovered that the most significant winds are often generated by rotating phenomena they termed mesovortices, which have length scales of an order of magnitude larger than tornadoes. Jeff is one of the world leaders in the assessment of thunderstorm hazard risk. For example, Trapp (2014) showed that the most damaging tornadoes tend to occur during multiday periods of tornado activity. Trapp and Hoogewind (2018) established a robust statistical (and physical) relationship between tornado activity and pan-Arctic sea ice extent. Jeff’s studies of severe thunderstorm frequency and intensity relative to the changing climate have revealed the likelihood for more intense and more frequent severe thunderstorm hazards in the future. His use of high-resolution, “convection-permitting” dynamical downscaling has also shown that the annual period over which damaging hail occurs will lengthen, begin earlier, and possess more volatility under climate change. Most recently, he and one of his students have developed yet another climate modeling approach that is providing the first evidence of potential increases in tornado intensity due to anthropogenic climate change. In summary, Jeff is well deserving of the Gilbert F. White Distinguished Award, and I am so pleased to see him so honored. —Donald J. Wuebbles, University of Illinois at Urbana-Champaign, Urbana

Thank you, Don, for your kind words, and thanks to those who supported this nomination. I’m truly honored to receive this recognition, but I readily acknowledge that it is most reflective of the countless contributions of my incredible students and collaborators. Indeed, I’ve been so fortunate during my career to have been influenced by the diverse experiences and thoughts of professional colleagues and students. I’ve likewise been blessed to have a wife and best friend, Sonia Lasher-Trapp, who also happens to be a research collaborator, sounding board, and fellow educator; and to have children, Noah and Nadine, who make me laugh and keep me humble. —Robert J. Trapp, University of Illinois at Urbana-Champaign, Urbana