Data comparison

Earth Map offers climate data provided by two different entities, (i) the European Centre for Medium-Range Weather Forecasts (ECMWF) from the Copernicus Programme, which supplies the fifth generation of global atmospheric climate analysis (ERA5) data and (ii) the Climate Hazards Center (CHC) from the University of California that offers Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS). Both sources contain more than 40 years of climate data which makes them suitable for determining long-term changes in terms of temperature and precipitation and to be used as reference data sets for climate change impact studies. There are several differences between both datasets, but the origin, the purpose of the data and their pixel size are the most striking ones. ERA 5 dataset reanalysis combines data from climate models with observations from around the world, by contrast, CHIRPS dataset combines observations from climate stations with satellite rainfall estimates. In terms of spatial resolution, the size of the pixel is much smaller 5 km in CHIRPS and larger 28 km in ERA5. It should be emphasized that the CHIRPS dataset was explicitly designed for monitoring agricultural droughts and environmental changes in land cover, allowing to place recent climate extremes in a historical context.

To name a few studies developed with the presented climate data, CHIRPS dataset has been used to assess wet and dry conditions along the semiarid Central-Western Argentina and to analyse long-term rainfall trends and variability in the Uttarakhand Himalaya. A recent study of the Potsdam Institute for Climate Impact Research (PIK) was prepared to evaluate the performance of ERA5 reanalysis and to document the progress made compared to ERA-interim for the fields of near-surface temperature and precipitation over Africa (Funk et al, 2015; Rivera et al, 2019; Banerjee et al, 2020; Gleixner et al, 2020).