Definitions and mathematical formulas of the indices used in ECA&D are provided below. A core set of 26 indices follows the definitions recommended by the CCl/CLIVAR/JCOMM Expert Team on Climate Change Detection and Indices (ETCCDI). Another 50 indices are specifically for Europe. Note that new research may lead to additional indices or changes in the indices definitions in the future.

The station series used for indices calculation in ECA&D are blended series. This means that they are made near-complete by infilling from nearby stations and updated using synoptical messages. Details on the blend and update proces are given in the specific FAQ or in Project Info > ATBD.

The 76 indices have been grouped in different categories corresponding with different aspects of climate change. The same grouping is also used in the pull down menus for presenting indices plots and maps.

Cloudiness  
Cold  
Compound  
Drought  
Heat  
Humidity  
Pressure  
Radiation  
Rain  
Snow  
Sunshine  
Temperature  
Wind