IMPACTS OF FUTURE CLIMATE-CHANGE ON THE SOUTHERN CANADIAN PRAIRIES - A PALEOENVIRONMENTAL PERSPECTIVE

Water and soil are critical to the prosperity of the southern Canadian prairies. Both have been strongly influenced by historic climate vari ability, and by even more significant climate changes that have occurr ed during the Holocene.These observations, together with general circu lation model projections of increasing aridity in this region, raise c oncerns about the potential impacts of future climate change. Collabor ative, multidisciplinary research conducted over the past five years a s part of the Palliser Triangle Global Change Project has focussed on geoscientific aspects of climate change in the driest portion of the C anadian prairie provinces. Reconstruction of past climates, based on m ultiple paleolimnological indicators (plant macrofossils, diatoms, ost racodes, algal pigments, sedimentology, mineralogy, and stable isotope geochemistry), demonstrates that the historic record of roughly 100 y ears does not adequately capture the range of climatic variability obs erved during even the last 2000 years. The response of hydrologic and geomorphic systems to past changes in climate documents a surprisingly dynamic landscape. The best analogues for projected future climates f eature a regional water table more than 4 m below its present level an d enhanced wind erosion. The paleoenvironmental record highlights the susceptibility of water and soil resources to climate-induced impacts that are likely to adversely affect human activities in the region ove r the next century.