Improvements to surface flux computations in a non-local-mixing pbl scheme, and refinements to urban processes in the noah land-surface model with the NCAR/ATEC real-time FDDA and forecast system

The MM5 MRF PBL scheme was revised to reduce the known problems of the under-prediction of daytime surface winds and the overprediction of the PBL heights. This revision was an effort to improve the real-time multi-grid four-dimensional data assimilation and forecast system's data assimilation methods and model physics schemes. More realistic methods for computation of free-convective turbulence, PBL height, and surface heat flux were developed and incorporated into the MRF PBL scheme. The modified MRF PBL scheme improves the PBL height prediction, reduces the daytime surface wind bias, and improves surface thermal and moisture variables.