Combined potential hydrologic impact of global warming, climate anomalies, and landuse changes to river basins of western canada and adaptation strategies to mitigate impact

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Hydrologic extremes have been occurring more frequently and in greater severity worldwide, including Canada, which may be due to the impact of climate change. Furthermore, western Canada (WC) can also be affected by climate anomalies such as El Nino Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and Pacific North American pattern (PNA). Intensity-Duration-Frequency (IDF) curves of most Canadian cities for designing municipal infrastructure are likely outdated, for they were mostly developed from single-site analysis of annual maxima rainfall assumed to be Extreme Value Type I distribution calibrated by the method of moments. Also, IDF curves are assumed to be "stationary" even though the effect of global warming could modify the intensity of future extreme rainfall events of various return periods, and so design storms based on existing IDF curves could be under-estimated, which could significantly reduce the safety standard of existing and future municipal infrastructure of Canada. On the other hand, the recent drought of 2001-03 affected Canada nationwide, causing substantial loss of agricultural revenue. How vulnerable are we to future climatic extremes? What prudent, adaptive measures should we implement to prepare for future climatic uncertainties? This proposal has six research objectives: (1) Replace obsolete IDF curves of many Canadian cities; (2) Develop regional IDF curves using the ensemble empirical mode decomposition method; (3) Simulate potential impact of climate change to the IDF curves of selected Canadian cities by a mesoscale atmospheric model driven with projected climate scenarios of the Intergovernmental Panel on Climate Change (IPCC), in a stand-alone and then a coupled modes; (4) Assess the combined potential impact of climate change and climate anomalies on the future water supply of selected river basins of WC; (5) Assess how could landuse changes due to developments and the potential shift in vegetation caused by a warmer climate would modify hydrology of major river basins; and (6) What adaptation strategies should be implemented to mitigate the potential impacts of climate change, climate anomalies, and landuse changes to our water resources?