Data for Multi-Timescale Evaluation of ERA5 Reanalysis and CCMP Merged Wind Products over the Bohai Sea, China

These data are organized into two original datasets according to temporal resolution: a daily dataset and an hourly dataset. The daily dataset is mainly used for analyses of decadal wind speed trends at onshore stations, with observations and ERA5 covering 1981–2023 and CCMP covering 1993–2023. The hourly dataset is primarily used for error evaluation of the wind products and for analyses of wind direction and offshore wind speed variations. In the hourly dataset, observations, ERA5, and CCMP all cover 2004–2023 at onshore stations, while at offshore stations they cover 2016–2024, except that CCMP is available only through August 2024. We also re-examined the observational dataset, unified the samples and temporal resolutions used for comparisons among different datasets and across different scales, and performed breakpoint detection and correction on the wind speed records used in the analysis of decadal onshore wind speed trends. The uploaded files are described as follows. observation_station_location.mat provides the locations and time coverage of the observational stations. hourly_datasets_2004_2024.mat and daily_datasets_2004_2024.mat contain the annual and monthly mean wind speed and wind direction calculated for each station from the hourly and daily datasets, respectively. hourly_errors.mat contains the hourly aggregated mean wind speed and wind direction over onshore and offshore stations, together with the corresponding errors, derived from the hourly dataset. monthly_errors_by_hourly_datasets.mat contains monthly mean wind speed and wind direction first calculated for each station from the hourly dataset and then aggregated into monthly mean values and corresponding errors over the onshore and offshore regions. annual_and_monthly_average.mat contains the regionally averaged annual and seasonal mean wind speeds and directions for all onshore or offshore stations from different datasets. annual_trend_aggregated.mat contains the annual and monthly mean wind speeds derived separately for the Bohai Sea onshore and offshore stations from different datasets. typhoon_comparison.mat provides the error statistics for ERA5 and CCMP during Typhoon Lekima and Typhoon Ampil. overall_estimation_of_wind_pairs.mat contains the overall error estimations for ERA5 and CCMP.