The use of Spanish historical archives to reconstruct climate variability

An overview is given of some strategies and techniques used to obtain climate-relevant information from a number of documentary records. By means of specific examples, three types of situations that are often encountered when trying to extract usual data from historical archives are illustrated. These include the treatment of noninstrumental meteorological observations, the interpretation of documents that provide explicit information on climatic events or impacts, and the development of climate proxies. Principal methodological issues are summarized. Furthermore, some guidelines that may be useful for other researchers interested in obtaining climatological information from historical sources are discussed.