A Dynamically Downscaled Surface Climate Dataset Based on CMIP6 Climate Projections for North America

This dataset was generated as part of the Canada1Water (C1W) initiative to provide high-resolution, physically consistent climate forcing for hydrological modelling of climate change impacts across Canada and transboundary basins. Regional climate projections were produced by dynamically downscaling CMIP6 global climate model simulations using the Weather Research and Forecasting (WRF) model over a North American CORDEX domain at 0.22° (approx. 24 km) resolution. An ensemble of nine simulations was generated by combining three driving GCMs (CESM2, MPI-ESM1.2-HR, MRI-ESM2.0) with three WRF physics configurations. The modelling framework includes a fully-coupled column lake model (FLake) to represent lake–atmosphere interactions. Simulations are provided for three time periods (historical: 1979–2015; mid-century: 2039–2060; end-century: 2079–2100) under the SSP3-7.0 scenario. The dataset includes daily surface climate variables required for hydrological modelling, including precipitation, near-surface air temperature (mean, minimum, maximum), humidity, water vapour pressure, wind speed, downwelling shortwave and longwave radiation, and surface pressure, and soil temperature fields. Due to data volume constraints, only monthly mean data in compressed NetCDF files are provided for direct download; daily or sub-daily data can be made available upon request. The dataset supports hydro-climate research, climate change impact assessments, and development of derived hydro-climatic products. A companion dataset with bias-corrected surface variables (including snow and PET) suitable for hydrological modelling is available here (historical) and here (mid- & end-century); the monthly normals of these derived datasets are also available through the Canada1Water Data Portal.