10:15 AM - 10:30 AM
[AAS05-06] Spatial-scale Characteristics of a Three-dimensional Cloud-resolving Radiation Budget based on Monte Carlo Radiative Transfer Simulations
Keywords:Cloud, 3D solar radiation, radiative energy budget, spatial resolution
A three-dimensional (3D) atmospheric radiative transfer (RT) model based on the Monte Carlo method was developed to evaluate the cloud-resolving radiation budget. The simulation data of stratocumulus (open and closed cell types) stimulated by a large eddy simulation model were used to obtain a detailed cloud field dataset at different spatial resolutions between 100 m and 1 km orders. The combination of the 3D RT model and LES data is a simple and practical way to evaluate the radiative energy budget in a cloud-resolving system because LES data are available in spatial continuity. Moreover, LES data produced by high performance computation are useful because of the large computational domain and the finer spatial resolution.
By applying the 3D RT model offline to a multiscale cloud field dataset, the 3D distribution and magnitude of the solar radiative heating rate were estimated for each spatial resolution. The results showed that the magnitude of the local solar radiative heating effect significantly changes in the range of spatial resolution between 100 m and 1 km. The solar radiative heating rate can reach 6 K/hr locally in the case of the spatial resolution at 100-m order, whereas it is approximately 1 K/hr at most in the case of the spatial resolution at 1-km order. However, the domain-averaged values of the solar radiative heating rates were almost invariant at different spatial resolutions. The results indicate that a radiation scheme for the cloud-resolving model needs to be constructed while considering spatial resolutions, along with cloud parameterization.
By applying the 3D RT model offline to a multiscale cloud field dataset, the 3D distribution and magnitude of the solar radiative heating rate were estimated for each spatial resolution. The results showed that the magnitude of the local solar radiative heating effect significantly changes in the range of spatial resolution between 100 m and 1 km. The solar radiative heating rate can reach 6 K/hr locally in the case of the spatial resolution at 100-m order, whereas it is approximately 1 K/hr at most in the case of the spatial resolution at 1-km order. However, the domain-averaged values of the solar radiative heating rates were almost invariant at different spatial resolutions. The results indicate that a radiation scheme for the cloud-resolving model needs to be constructed while considering spatial resolutions, along with cloud parameterization.