Köppen
EN

Data sources

All scenes are rendered from publicly available data. We process the data (cropping, averages, anomalies, interpolation) but never alter any measured values. Which source a scene uses is stated on its page.

Reanalyses and climate

  • ERA5 (Copernicus Climate Change Service C3S, ECMWF): hourly reanalysis of the weather since 1940; the basis of most scenes. Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use of the information.
  • Köppen-Geiger classification following Beck et al. (2018), recalculated by us from ERA5 for each period (climate atlas).
  • NCEP/NCAR Reanalysis 1 (NOAA PSL): polar vortex since 1948.

Ocean and El Niño

  • GODAS (NOAA NCEP, Global Ocean Data Assimilation System): ocean temperatures at depth since 1982.
  • Oceanic Niño Index (ONI) (NOAA Climate Prediction Center): El Niño and La Niña years since 1950.

Stations

  • GHCN-Daily (NOAA NCEI): daily values from weather stations, including for Texas and the Storm of the Century 1993.
  • Deutscher Wetterdienst (DWD), Open Data: station measurements. Data basis: Deutscher Wetterdienst.
  • Météo-France and MeteoSwiss: station measurements for windstorm Lothar 1999.

Storms

  • HURDAT2 (NOAA National Hurricane Center) and IBTrACS (NOAA NCEI): tracks of tropical cyclones since 1851.
  • Windstorm tracks in Europe: our own tracking of low-pressure systems in ERA5.

Forecasts

  • GFS and GEFS (NOAA NCEP): forecast and ensemble for the polar vortex.
  • ECMWF IFS (Open Data): forecast for the polar vortex.
  • Seasonal forecasts from the Copernicus Climate Change Service (C3S, nine models): snow in the coming winter.

Forecast scenes show the model run stated in each case; they are not an official forecast.

Economy and damage

  • World Bank and FAO as well as NOAA: figures on the economy and harvests for the scene “The Bill”.

Note

The scenes are provided for information and entertainment. For warnings and decisions in dangerous weather, only the official weather services apply; in Germany, that is the Deutscher Wetterdienst.