Shallow cumulus convection over land in cloud-resolving simulations with a coupled ray tracer
Abstract
We present simulations of cumulus convection over land with shortwave radiation computed by a Monte Carlo ray tracer coupled to the flow solver. Ray tracing delivers very realistic in-cloud heating rates and global horizontal irradiance fields. The necessary performance of the ray tracer has been enabled by the raw power of GPU computing and from techniques for accelerating data lookup and ray tracer convergence. We used a case study over a grassland in the Netherlands to compare simulations with a coupled ray tracer to those with a conventional two-stream solver, and to test ray tracer convergence. We demonstrate that the simulated cloud evolution is insensitive across a wide range of samples sizes in the ray tracer. Furthermore, simulations with a coupled ray tracer produce surface irradiance patterns that resemble observations and that strongly feed back to the evolution of clouds via locally enhanced surface heat fluxes.
Keywords
Cite
@article{arxiv.2208.05247,
title = {Shallow cumulus convection over land in cloud-resolving simulations with a coupled ray tracer},
author = {Menno A. Veerman and Bart J. H. van Stratum and Chiel C. van Heerwaarden},
journal= {arXiv preprint arXiv:2208.05247},
year = {2023}
}
Comments
12 pages, 4 figures, submitted to Geophysical Research Letters