As cheias do rio Douro no Porto (Portugal) do Século XVIII

Abstract

The floods occurred on the estuary of the river Douro in the eighteenth century, in the city of Porto, allow a double approach to the history of the climate. On the one hand, applying information treatment models used in some more recent studies it is possible to make a serial analysis of the years of floods, their chronological distribution, frequency, duration and intensity associated with meteorological phenomena and their impacts. On the other hand, we tried to understand how values, beliefs, attitudes, knowledge reflect different perceptions of events, between sensations of vulnerability, learning and change. The analysis of information, such as cartographic, ecclesiastical and municipal sources, as well as the testimony of a merchant, over successive years (1717-1800), allowed reconstituting the dimension of the phenomenon comparing with the climatic contexts of other geographical spaces. We conclude that the informant's position, the fragility and, at the same time, the power of information is also a social construction.