Effects of interactive 3D radiation on cloud development
Cloud development is not only affected by humidity or atmospheric stability, but also by absorption and emission of radiation. The effect on cloud development is currently studied at MIM. Two new approaches to calculate 3D heating and cooling rates have been developed which are, for the first time, fast enough to be actually used in cloud resolving models: the „Neighboring Column Approximation“ (NCA) for 3D thermal heating rates (Klinger and Mayer, 2015) and the Tenstream Solver for solar and thermal radiation (Jakub and Mayer, 2015).
An example of a cloud-resolving simulations (UCLA-LES) of a shallow cumulus cloud field are shown. The distribution of liquid water for simulations with and without interaction with 3D thermal radiation for an identical time step are illustrated. Deeper and more organized clouds are found if 3D thermal radiation is considered.