Computed 1961-2023 Summer Metrics

Data to accompany the manuscript: "Summers over land and ocean are becoming longer, transitioning faster, and accumulating more heat"1961-2023_ALL_summer_stats.nc (zipped due to size): Computed data of summer metrics per year, per grid cell at ERA5 resolution (0.25 deg x 0.25 deg): length (days), start/onset day, end/withdrawal day, mean summer temperature (K), accumulated heat (K days), and ancillary values. These metrics are based on a definition of summer as being when a smoothed Fourier regression to the daily mean 2m temperature time series from ERA5 crosses above/below the 75th percentile daily mean over 1961-1990 for that grid cell. Values are only valid for midlatitudes from 23.5-70 deg N and S where a clear seasonal cycle is observed.1961-2023_ALL_summer_gradient_stats.nc: Gradient/slope (K/day) of the Fourier fit to the daily mean 2m temperature time series from ERA5 on the days of summer onset and withdrawal for each grid cell. Values are only valid for midlatitudes from 23.5-70 deg N and S where a clear seasonal cycle is observed.*city*_summer_stats: same metrics and units as in the above data files but calculated for ten individual cities via data from a single observational site in the GHCN-Daily dataset