The weather behind words – new methodologies for integrated hydrometeorological reconstruction through documentary sources

Abstract

Historical climatology has remarkable potentiali ties to produce climatic reconstructions with high temporal resolution. However, some methodological limitations hin der the spatial development of this discipline. This study presents a new approach to historical climatology that over comes some of the limitations of classical approaches, such as the rogation method or content analysis: the Cost Oppor tunity for Small Towns (COST). It analyses historic docu ments and takes advantage of all sorts of meteorological in formation available in written documents, and not only the severest events, to therefore overcome the most prominent bottlenecks of former approaches. COST relies on the fact that using paper is very costly, so its use to describe meteo rological conditions is hypothesised as being proportional to the impact they had on society. To prove the validity of this approach to reconstruct climate conditions, this article exem plarily uses the Municipal Chapter Acts of a small town in southern Spain (Caravaca de la Cruz), which span the 1600– 1900 period, and allows reconstructions to be obtained on a monthly basis. Using the same documentary source, the three approaches were used to derive respective climate recon structions, which were then compared to assess climate sig nal consistency and to identify possible caveats in the meth ods. The three approaches led to a generally coherent series of secular variability in the hydrological conditions, which agrees well with previous study results. The COST approach is arguably more objective and less affected by changes in societal behaviour, which allows it to perform comparative studies in regions with different languages and traditions