Research on the influence of microtopography based on FDTD numerical simulation

This study focuses on the Liupan Mountain region in Ningxia, employing a combination of ground observation and the Finite-Difference Time-Domain (FDTD) method to investigate the effects of microtopography on local meteorological elements such as temperature, precipitation, and wind field distribution. The slope, aspect, and elevation values of microtopography in the study area were extracted using ArcGIS technology. Through multivariate regression analysis, the coupling relationship between slope, elevation, and local wind speed was quantified (R2=0.987, p<0.01), confirming that microtopographic heterogeneity is a critical factor driving microclimatic variation. Utilizing a coupling numerical model based on the FDTD method, a meteorological simulation framework was constructed that integrates terrain-correction parameterization and dynamic sub-grid turbulence modeling. This enabled high-resolution spatiotemporal simulation of temperature, precipitation, and wind speed in flat areas adjacent to the study region. The results indicate systematic differences in temperature distribution between microtopographic regions and nearby flat areas, with a root mean square error of 4.83°C. The winter precipitation in the windward slope increased by 33% compared to the leeward slope (29.43 mm vs. 9.723 mm), and average wind speed in microtopographic areas increased by 68.83% compared to flat regions, facilitating the occurrence of instantaneous strong winds. These findings can provide valuable insights for disaster prevention and mitigation efforts in microtopographic regions.