ERA5

From variable 3.7
Summary of observation-based historical datasets with specific and/or relative humidity available
reference

source
ECMWF
data type
Global atmospheric reanalysis
spatial domain
Global
spatial resolution
0.25° x 0.25°
temporal coverage
1950 - present
time step
Hourly; Daily; Monthly
data format
GRIB; NetCDF
comments
5th generation reanalysis. Relative humidity and specific humidity are provided on pressure levels only. Surface relative humidity can be estimated from the values on pressure levels or computed using 2 m air temperature and dew point temperature (information on both temperature variables are provided in Near Surface temperature subsection).