Exposure of rural communities to climate variability and change: Case studies from Argentina, Colombia and Canada

Abstract

This paper presents results from studies of exposure to climate change and extreme events in the Mendoza River Basin in western Argentina, the Chinchiná River basin in the Colombian Andes, and the Oldman River basin and Swift Current Creek watershed in the Canadian Prairies. These case studies are a major component of an international research project: “Vulnerability and Adaptation to Climate Extremes in the Americas” (VACEA). This project is very much interdisciplinary; with social and natural science providing context and direction for research in the other realm of scholarship, producing insights that very likely would not arise from a more narrow disciplinary perspective. A large number of interviews with local actors revealed that agricultural producers and local officials recognize their high degree of exposure and sensitivity to climate variability and extreme weather events, although they generally do not associate this with climate change. Case studies of exposure demonstrate that the perceptions of the local actors are consistent with the nature of the regional hydroclimatic regimes. In all four river basins, climate variability between years and decades masks any regional expression of global climate change. These modes of periodic variability dominate the paleoclimate of past centuries and the recorded hydroclimate of recent decades. The exposure variables examined in this paper, indices of stream flow, snowpack, water excess and deficit, vary in coherence with the characteristic frequencies of large-scale ocean–atmosphere circulation patterns, specifically the ENSO and PDO. Projections of the future states of these variables require the use of climate models that are able to simulate the internal variability of the climate system and the teleconnections between ocean–atmosphere oscillations and regional hydroclimate.