ALBERT

Description: Ice clouds play a key role in the atmospheric radiation budget, both by reflection of shortwave radiation and absorption-emission of longwave radiation. Through these radiative interactions, ice clouds can set atmospheric temperature gradients and thereby influence atmospheric circulation regimes. The radiative signature of ice clouds strongly depends on their macro- and microphysical characteristics, as well as their optical properties. While the new generation of storm-resolving models improves the representation of the vertical velocities that drive cloud formation, subgrid-scale differences, for example in ice optics and microphysics, generate large variability in the modeled atmospheric cloud-radiative heating (CRH) rates (Sullivan and Voigt, 2021). We propose both an idealized single-column and more realistic two-dimensional transect approach for investigating CRH, using the new ecRad radiative transfer module (Hogan and Bozzo, 2018). First, in a series of single-column calculations, we evaluate the impact of realistic perturbations in macro- and microphysical properties, such as cloud-top temperature and ice crystal effective radius, on CRH. For this approach, a heating sensitivity matrix visualization is presented as the response for the different levels of macro-micro properties perturbations. Secondly, we study the impact of using three different ice optical schemes (Fu, 1996; Fu et al., 1998; Yi et al., 2013; Baran et al., 2016) on CRH over three latitudinal transects located in the Eastern Pacific, Western Pacific, and passing over the Asian Monsoon Area. For each of these transects, ecRad is driven by realistic atmospheric conditions provided by ERA5.