Archives, histoire du climat et pluviométrie : un exemple sud-américain

Archival climate history survey and instrumental records : a south-american example

¹ U.R. 32 Greatice, IRD, Montpellier
² Maison des Sciences de l'Eau, IRD, B.P. 64501, F-34394 Montpellier Cedex 5

Auteur de correspondance : gioda_ird@yahoo.com

Abstract

The aim of this research is to reconstruct a regional history of climate, and particularly rainy seasons, using first of all printed chronicles, travellers and explorers diaries and press information. We secondly study archival documents to have a closer point of view of history. Potosi, the silver city of Eldorado (Peru then actually Bolivia, the Andes, 4000 m a.s.l.) is a good field study because of its richness from 1545 (the year of the first human settlement) which was characterized by coin control by Spain, the importance of the hydraulic and mill power in the mining industry built in an arid and cold environment, and a strong administrative domination by Spaniards and the Church of the city and its neighbourhood. The quality of all these different proxy data is estimated using instrumental records especially rainfall long-time series. Archival climate reconstruction from Town Hall reports (1585-1816) has a similar distribution of second half XX^th meteorological records. On the other hand, climate history periods (reconstructed from printed chronicles, such as travellers and explorers diaries) have generally a different statistical distribution with a higher number of droughts and catastrophic natural events that could mean rather a lower quality of reconstruction than a climatic change.