Here a set of global 1‑km resolution Köppen-Geiger climate classification maps for the present day (1980–2016) and for projected future conditions (2071–2100) under climate change.
Citation: Beck, H.E., N.E. Zimmermann, T.R. McVicar, N. Vergopolan, A. Berg, E.F. Wood: Present and future Köppen-Geiger climate classification maps at 1‑km resolu...
In the academic literature EM-DAT seems to be the standard.
It is quite a comprehensive dataset covering ~21,000 disasters worldwide and going back to 1900 (don't know if that is historical enough). It also classifies disasters according to group and subgroup which can be useful.
The older Sentinel data are available upon request in the Long Term Archive (LTA) Access. For the current status, see https://scihub.copernicus.eu/userguide/LongTermArchive .
You should be able to order data from the LTA either through the Copernicus Open Access Hub (https://scihub.copernicus.eu/dhus/#/home) which requires a registration.
An alternative in ...
UTC (Coordinated Universal Time) is the only way that makes sense for a global dataset. Using local timezones would be an absolute nightmare for exactly this reason.
I found several references to UTC in the ERA5 data documentation.
'time' in analyses
Each analysis has a validity time, i.e. the time the data values refer to (not the time when the ...
Finally I found some useful links for station-based data for period 1981-2010:
data for Austria:
data for Germany:
data for switzerland: