ERA5 / ERA5-Land
Free
ECMWF's hourly global reanalysis — the default gap-free climate forcing record for ungauged catchments worldwide.
6 tools · Topic
Climate Reanalysis Datasets
Reanalysis blends historical observations with a numerical weather model to produce a physically consistent, gap-free climate record — ERA5, MERRA-2 and NOAA CFSR are the workhorses. Unlike the projection datasets on the Climate Projections page, these describe the past and present, not future scenarios, which makes them the default forcing data for ungauged and data-sparse catchments.
A consistent annual global land cover record at 300m from 1992 — long enough to trend land-use change against.
The longest satellite soil moisture record available — merged active+passive retrievals back to 1978, free, no login.
MERRA-2
Gov-Public
NASA's satellite-era atmospheric reanalysis — hourly global fields from 1980, the default alternative to ERA5.
NOAA CFSR / CFSv2
Gov-Public
NCEP's coupled atmosphere-ocean-land reanalysis, sub-daily, 1979–present — strong where ocean coupling matters.
Programmatic access to ERA5 and the Copernicus Climate Data Store — the world's reanalysis workhorse.