This repository contains the figure data and code required to generate the figures that appear in Igel and van den Heever (2021) Invigoration or enervation of convective clouds by aerosols? in Geophysical Research Letters. We present new theoretical calculations which starkly contrast previous results. Prior foundational work suggested that aerosols strongly invigorate convective cloud updrafts via changes to cold-phase processes. We show that the peak magnitude of invigoration by this mechanism is substantially reduced for cold-based storms. For warm-based storms, the updrafts are weakened, not strengthened, by aerosol-induced changes to cold-phase processes. Our calculations show that if invigoration occurs, it is driven primarily by changes to warm-phase processes and maybe largest well before the storm reaches maturity. The calculations are based on a new formulation of the moist adiabatic lapse rate that accounts for freezing, supersaturation, and condensate loading. The results significantly reshape our understanding of the impact of aerosols on convective updrafts.

Theoretically generated data. See the paper and code for full details.

Figure data and Matlab code used to create Figures 1, 3, and 4. Includes raw code to solve the moist adiabatic lapse rate equation that was derived in the paper.
Update 10/2023: The same code has now been used to generate a figure that appears in Varble et al (2023) in Atmospheric Chemistry and Physics. One additional file has been deposited in support of that publication.