Improved national GDP and population data for ISIMIP3 #10

We provide new and improved versions for national GDP and population data basing on longer observational periods. Since national GDP and population data are mostly used in postprocessing we think it justified to take down the current version.

The improved datasets cover an observational period until 2020 basing and a total of 249 countries. Future projections were updated to more recent SSP scenarios. Please note that while the previous GDP data was given in 'PPP 2005 US$' the new version is in 'PPP 2005 Int $'. Since the new national data only begin in 1950/1965, we do not provide 1850soc resp. 1901soc data anymore.

We provide gridded population data, that is based on HYDE v3.3 (private communication with K. Klein Goldewijk, to be published). Just like the original dataset we provide total, rural and urban population per grid cell. The original data was on a 1/12°×1/12° grid and has been interpolated to ISIMIP's 1/2°×1/2° grid via cdo remapcon. The population maps were constructed in conjunction with the fractional countrymask (https://doi.org/10.48364/ISIMIP.635131.1).

Before the year 1950 HYDE provides data every ten years, the intermediate years have been filled by linear interpolation. Also, the original HYDE data ends in 2020, so to cover the whole ISIMIP3a time frame the final year 2020 has been duplicated as 2021. This way annual coverage of 1850 to 2021 has been achieved.

All grid cells of a country, as defined by the ISIMIP fractional country map (https://doi.org/10.48364/ISIMIP.635131.1), have been rescaled such that the country's total population matches the numbers provided in the national population data (https://population.un.org/wpp). Since the national data only starts in 1950, all years prior to 1950 have been rescaled by the scaling factors of 1950.

It would be very helpful to have a link to the revised data set here.

Unfortunately we found an error in the rescaled gridded population for ISIMIP3a we published this week. There was a mistake in the coastal regions that led to a too high population in those grid cells. The issue is fixed now.

The new files are available at DKRZ and can be downloaded from https://data.isimip.org/search/tree/ISIMIP3a%2FInputData%2Fsocioeconomic%2Fpop/ and the new DOI for the data is https://doi.org/10.48364/ISIMIP.822480.2.