NOTICE (March 2018): This website provides access to the CDIAC archive data temporarily. It will be gradually transitioned into data packages in the new ESS-DIVE archive. This site will continue to operate in parallel during and after the transition, and will be retired at a future date. If you have any questions regarding the data or the transition, please contact

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Climate Indices

Climate indices are diagnostic tools used to describe the state of the climate system and monitor climate. They are most often represented with a time series, where each point in time corresponds to one index value. An index can be constructed to describe almost any atmospheric event; as such, they are myriad. Therefore, CDIAC provides these links to other web sites to help guide users to the most widely used climate indices, which in many cases are updated monthly.

Data Set Website/Name