Simulation of Summer Land Air Interactions in East China Based on Different Land Use Products

Abstract

Land use and land cover change （LUCC） affects local weather and climate by influencing local land surface processes and land-air interactions.To investigate the effects of the LUCC products on land-air interactions， this paper uses three sets of LUCC data， USGS， Landsat and MODIS， to simulate and study the effects of the LUCC products on soil and near-surface temperatures and humidity in East China.The results show that the differences in land use types among the LUCC products are mainly in urban， agricultural land and natural vegetation dominated by grasslands and forests.Compared with USGS， Landsat and MODIS urban and forest areas increased by more than 2% and 15%， respectively， while the agricultural area decreased by about 17%.The increase in Landsat and MODIS urban areas increased soil temperature and moisture， and increased sensible heat flux by 28.1 W·m-2 and 68.3 W·m-2， respectively， and decreased latent heat flux by 28.3 W·m-2 and 81 W·m-2 respectively， increasing 2-m air temperature by about 1.5 ℃ and decreasing relative humidity by about 9%.The change of agricultural and grassland in USGS to forests in Landsat and MODIS changed the spatial distribution of soil temperature， moisture， and near-surface energy fluxes， temperature and humidity.However， these changes are more complex compared to the changes in the urban area.Additionally， urban area changes between LUCC products have a greater impact on soil temperature， moisture and near-surface energy fluxes， temperature and humidity than agricultural and natural vegetation changes.Finally， by comparing the correlation， root mean square error， mean bias and index of agreement of the soil temperature， soil moisture， 2 m temperature and relative humidity results of the three experiments with GLDAS （the Global Land Data Assimilation System）， station observation data， it can be found that the simulation performance of near-surface meteorological conditions using the Landsat product （more accurate and detailed product） is better than that of USGS and MODIS product simulation results.

Keywords

• land use and land cover change
• wrf model simulation
• urban expansion
• land-air interaction