A 1980-2020 Daily Meteorological Dataset over China for Near-Surface Variables

This dataset provides daily near-surface meteorological forcing data over China at 0.1° spatial resolution for the period 1980-2020. It covers four variables: 2-meter temperature (K), relative humidity (%), surface pressure (hPa), and 10-meter wind speed (m/s) with U/V components. The dataset was generated by merging three state-of-the-art reanalysis products (ERA5-Land, MERRA-2, JRA-3Q) with station observations from the China Meteorological Administration, using the Extended Double Instrumental Variable (EIVD) method, supplemented by monthly bias correction and topographic adjustment. Validation against 50 independent CMA stations shows that the merged product outperforms each individual reanalysis and the widely used CMFD2.0 product, particularly in the data-sparse western China region. The dataset also demonstrates robust capability in detecting compound extreme events. File format: NetCDF4 (.nc), following CF metadata conventions Spatial coverage: China (70°E–140°E, 15°N–55°N) Temporal coverage: 1980-01-01 to 2020-12-31 Temporal resolution: Daily File naming convention: MERGED_V0101_B-01_01dy_010deg_YYYYMM.nc Variable list: temp: 2-meter temperature (K) rh: Relative humidity (%) pres: Surface pressure (hPa) u: 10-meter U wind component (m/s) v: 10-meter V wind component (m/s) Usage notes: Daily product is the primary recommended dataset. The U/V wind components are reconstructed using station directional ratios; suitable for qualitative analysis and models requiring vector wind input. Funding: This work is supported by the National Key Research and Development Program of China (Grant No. 2024YFF0810600) and the National Natural Science Foundation of China (Grant No. 42471115).