Simulating the effects of land urbanization on regional meteorology and air quality in Yangtze River Delta, China

\Land urbanization caused by human activities is increasingly converting natural land surfaces to artificial ones and modifying land surface parameters. This can lead to changes in weather conditions and further effects on air pollutants. This study examines the influence of land urbanization on meteorology and air quality in the Yangtze River Delta (YRD) by simulating the impacts of land-use/land cover (LULC) changes on meteorology and air quality. Our results show that the temperature at 2m increases by 0.2-0.7 degrees C, and the planetary boundary layer height exhibits a maximum growth during the daytime of 116.74 m after updating LULC. The average reduction of 10-m wind speed is 0.29 m/s, and the maximum decrease is 0.52 m/s, which occurs in the daytime due to increased surface resistance. Furthermore, PM2.5, NO2, SO2, and ozone are sensitive to these meteorological changes in the WRF-CMAQ model. Additionally, land urbanization results in a decrease in the PM2.5 concentration in most urban areas for the same emission source. However, land urbanization aggravates photochemical smog pollution, which is dominated by O-3. The findings of the study can be used as a reference for policymakers and urban planners to help implement effective air pollution prevention and control measures and ensure the rational use of land resources.