Urbanization Enhances Tornado Potential: A Case Study
Tornadoes pose enormous risk of economic loss and casualty in United States. As the most extreme case of land use change, urbanization potentially impacts the physical processes related to tornado formation and intensification. Here we explored the simulated impact of Kansas City urbanization on the tornado potential of a tornadic supercell case occurring on 1-2 July 2015. We found that the urbanization effect of Kansas City greatly enhances tornado potential through (a) strengthening the southerly low-level streamwise vorticity; thus, forming stronger rotating updrafts and (b) intensifying the advection of southeasterly near-surface streamwise vorticity into the rotating updrafts. The former results from an enhanced east-to-west perturbation pressure gradient and the latter is mainly due to the larger temperature contrast as a result of a stronger cold pool. Both of which is caused by an intensified storm produced by Kansas City urbanization.