Idealized simulations of aerosol influences on tornadogenesis

Abstract

Numerical simulations of an idealized supercell thunderstorm were performed to assess effects of increased aerosol concentrations acting as cloud condensation nuclei (CCN) and giant CCN (GCCN) on tornadogenesis. Initial background profiles of CCN and GCCN concentrations were set to represent "clean" continental and aerosol-polluted environments, respectively. With a reduction in warm- and cold-rain processes, the polluted environment produced a longer-lived supercell with a well-defined rear flank downdraft (RFD) and relatively weak forward flank downdraft (FFD) that produced weak evaporative cooling, a weak cold pool, and an EF-1 tornado. The clean environment produced no tornado and was less favorable for tornadogenesis. Copyright 2008 by the American Geophysical Union.