P50  An Explicitly-Coupled Shallow Convection Parameterization with Planetary Boundary Processes

Hong, Song-You, Jihyeon Jang, Hyeyum Hailey Shin, and Junhong Lee, Yonsei University, Seoul, Korea

The eddy-diffusivity scheme of Tiedtke is evaluated, focusing on the dependency upon the deep convection schemes. Drying and warming near the top of the boundary layer and countering effects its above are observed. These effects are pronounced over the oceans, which leads to the modulation of tropical precipitation. It is found that the Tiedtke scheme shows similar effects regardless of the choice of the deep convection scheme. A revised scheme that explicitly couples the planetary boundary layer and shallow convection, which is the revision to the TiedtkeÕs approach, is proposed and evaluated. The new scheme incorporates the turbulent properties in the boundary layer into the shallow convection process. It is found that the simulated climatology in a global model is improved by reducing the exaggerated mixing in the original Tiedtke scheme.