Assessment of radiation options in the advanced research WRF weather forecast model

Poster PDF

Description

The broad band, correlated k-distribution model, RRTMG, developed at AER with ARM support for application to climate and weather forecast models, was released during 2009 as a radiative transfer option in the Advanced Research WRF (Weather Research and Forecasting) model. An assessment among RRTMG longwave and shortwave radiative transfer and the other radiation options in WRF will be presented for several forecast cases. Evaluation of the results and radiative closure are accomplished by comparison to surface measurements from the ARM Climate Modeling Best Estimate (CMBE) data set for the SGP and TWP sites and at the top of the atmosphere by comparison to several satellite data sets. In addition to radiation fields, the simulation of cloud amounts and cloud optical properties will also be assessed. The result of sensitivity studies relating to the frequency of the radiative transfer calculation and the application of the Monte-Carlo Independent Column Approximation (McICA) technique in WRF forecasts will also be described.