proxy

Indirect climate indicators, obtained from geological and biological records, as well as from documentary sources, from which information of interest can be extracted for the study of past climates. Thanks to them, it is possible to reconstruct the climatic behavior of very ancient periods of history, for which instrumental meteorological observations are not available. Their origin is highly diverse, coming from sediments and soils, as well as from ice samples, tree growth rings, fossil pollens, corals, and documents of all kinds, such as chapter minutes, ecclesiastical records, or ships' logbooks.