Geologist Patrick Abbott, professor emeritus at San Diego State University, explorer, guide, and author of several books including "Geology of Mission Trails Regional Park" continues our OnTopic lecture series with the last of four presentations about natural events and their impact on the San Diego region. Wildfires have become part of California life. Of the 17 largest wildfires in California history, 16 have occurred since 2003, and nine of the 17 have occurred in 2020 and the first nine months of 2021. Wildfires now are more frequent, larger, and hotter. Our preparation to reduce wildfires relies on forest thinning and prescribed burns, on making homes resistant to flames, as well as discouraging further human encroachment into wilderness areas. Participation in the presentation is free of charge, but registration is required.