In this study, the radiation scheme BCC-RAD developed for global climate models is implemented into the Global-Regional Integrated SysTem (GRIST) model as an alternative to the default RRTMG (general circulation model (GCM) version of the Rapid Radiative Transfer Model) scheme. Its impact on the simulated climate is comprehensively evaluated with different physics parametrization package. The results indicate that under the default physics parameterization package of GRIST (PhysC), BCC-RAD improved the simulated cloud cover, atmospheric temperature, and relative humidity. Upon the inclusion of the PhysCN parameterization package, BCC-RAD exhibited further improvement in simulating cloud cover and radiative forcing (particularly longwave radiative forcing) relative to RRTMG. Additionally, BCC-RAD improves the simulation of atmospheric temperature and hence notably diminishes the apparent overestimation of atmospheric humidity seen in RRTMG. This study demonstrates the advantages of BCC-RAD over RRTMG in certain aspects of the GRIST-simulated climate, verifying its capability for the climate-oriented configuration of GRIST.

BCC-RAD; GRIST; climate simulation; radiation scheme evaluation