Impacts of Remote-Sensing-Derived Terrain and Land-Use Datasets on Mesoscale-Model Simulations of an Extreme Heat Event over Henan, China: Sensitivity Experiments and Evaluation Against In Situ Observations and MODIS LST

Remote-sensing-derived static terrain and land-cover datasets influence regional extreme heat simulations, but their effects on internal model responses and temperature performance require joint assessment. Five numerical experiments were conducted for the June 2022 Henan heatwave using five configurations drawn from three terrain datasets and four land-cover datasets. Atmospheric forcing and model physics were identical, and the inner grid spacing remained fixed at 3 km. Simulated skin temperature (TSK) was evaluated against Moderate Resolution Imaging Spectroradiometer (MODIS) land-surface temperature after pixel-level spatiotemporal matching. Simulated 2 m air temperature (T2) was evaluated against observations from 111 national meteorological stations. Two diagnostic pathways examined terrain-related and land-cover-related responses. Replacing MODIS15s-lake with MCD12Q1 changed the dominant land-use category in 22.2% of Henan grid cells. Daytime sensible heat flux difference fields had spatial root-mean-square (RMS) values exceeding 20 W/m2. On the WRF Preprocessing System (WPS)-mapped 3 km grid, terrain fields derived from ASTER30 and GMTED5m had mean absolute differences of 7.5 and 22.8 m, respectively, relative to GMTED30s. Terrain-height and surface-pressure differences were strongly inversely correlated (R = −0.9990 to −0.9993), supporting hydrostatic consistency. Direct interaction residuals indicated non-additive TSK and T2 responses, and their full-period mean fields had spatial RMS values of 0.421 and 0.225 K, respectively. All configurations exhibited pooled TSK warm biases of 5.52–5.74 K, compared with an inter-configuration bias spread of approximately 0.22 K. No configuration consistently minimized temperature errors across variables and periods, and larger internal response magnitudes did not consistently correspond to smaller temperature errors. For this event and model configuration, products with higher nominal native resolution did not consistently improve temperature simulation; the independent resolution effect was not isolated. The framework combines internal diagnostics with station and satellite evaluation to assess remote-sensing-derived static inputs.