Copernicus Climate Data Store is a huge archive of various datasets providing the information about Earth’s past, present and future climate. It is freely available and functions as a one-stop shop to explore climate data.
Following datasets can be of interest of agriculture:
ERA5-Land hourly data from 1981 to present - Various types of temperatures (surface, soil, ...), lake ice cover, snow cover, soil water,radiation, evaporation and runoff, leaf area indices, etc.
ERA5 hourly data on pressure levels from 1979 to present - for atmospheric analyses
Agrometeorological indicators from 1979 to 2018 derived from reanalysis - aggregation of agriculture relevant variables in a convenient form.
Register for free to obtain access to the Climate Data Store and its Toolbox here: https://cds.climate.copernicus.eu/user/register
For more information about the Copernicus Climate Data Store, please visit following website: https://cds.climate.copernicus.eu/cdsapp#!/home