Improving mesoscale modeling using satellite-derived land surface parameters in the Pearl River Delta region, China

Land surface parameters play an important role in mesoscale modeling by regulating the regional heat flux and hydrological cycle. Recently, significant urbanization and afforestation occurred in the Pearl River Delta (PRD) region, China, which exert an important effect on local meteorology and thermal circulation. But previous studies failed to capture the complex changes of the surface characteristics in the PRD and thus were difficult to accurately describe the land-atmosphere coupling. In this study, high-resolution Moderate Resolution Imaging Spectroradiometer observations are used to specify the land cover type, green vegetation fraction, and leaf area index in the Weather Research and Forecasting model. Comparisons with ground-based observations during eight episodes, as well as satellite measurements, all indicate an improved model performance when the satellite-derived land surface parameters are assimilated. Moreover, the remote sensing data accurately reflect the surface inhomogeneity and successfully represent the intensity and spatiotemporal characteristics of the urban heat island (UHI) effect. The UHI effect in turn modifies the local thermal circulation by enhancing the urban-rural horizontal advection and initiating the urban heat island circulation, as well as interacting with the sea/land breeze over the PRD. This work not only improves the understanding of local meteorological simulation and forecasting but also sets the stage for further research on the feedback between air quality and meteorological responses due to land cover changes.Meteorology & Atmospheric SciencesSCI(E)3ARTICLEsongyu@pku.edu.cn116325-634611