Data for dem4cli : demographics for climate

Data necessary to run https://github.com/rosapietroiusti/dem4cli/

Data comes from a number of other sources and is collated for ease of running dem4cli.

The data sources are:

1. Wittgenstein Center Data Explorer v2 population cohort size from 1950 to 2100 per country (at snapshots every 5 years) (http://dataexplorer.wittgensteincentre.org/wcde-v2/), available for SSP1, SSP2, SSP3. Cohort size data from WCDE is available at a country level for the period 1950-2100 (reconstructions up to 2015 and projections thereafter) expressed for 5-year age cohorts at 5-year time snapshots.
2. ISIMIP gridded population data reconstructions and projections at 0.5 degrees for SSP1, SSP2 and SSP3 from ISIMIP3a/b (histsoc up to 2021 based on HYDE v3.3 Klein Goldewijk et al.2022), from 2022 SSP projections (based on Gao et al. 2020 https://doi.org/10.5065/D60Z721H and https://doi.org/10.7927/q7z9-9r69), scaled to match ISIMIP national population reconstructions projections under different SSPs (from UNWPP and Samir and Lutz 2017). Projections are based on the national SSP scenarios from Lutz et al. (55) and gridded population projections from the National Center for Atmospheric Research (NCAR).
3. Isipedia fractional country masks at 0.5 degrees are used to match the datasets (Perrette 2023, https://github.com/ISI-MIP/isipedia-countries).
4. Metadata on income levels and regions from World Bank (WB 2023, https://datatopics.worldbank.org/world-development-indicators/the-world-by-income-and-region.html)