Impacts of climatic and environmental changes to Hydrologic Extremes and Adaptation strategies

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In recent years, severe storms have been occurring more frequently and in greater intensity across the world because of global warming, which could cause existing Intensity-Duration-Frequency (IDF) curves for engineering design obsolete, e.g., thousands of basements of Edmonton were flooded in 1995, 2004 and 2012, by storms which based on existing IDF curves for the City are supposed to occur once every 100 years. In June 2013, the southern Alberta flood incurred a damage of $6 billion. On the other hand, the drought of 2001/02 had caused loss of multibillion dollar revenues from agriculture. Another impact of warming will be the water availability of most Canadian watersheds dominated by snowpack because a warmer climate means an earlier onset of spring snowmelt and enhanced evaporation loss in the summer, resulting in decreased summer streamflow most needed for summer growing seasons. This research will advance our understanding of climate change and our ability to predict the impact of warming to changes in the climate and water resources of Canada. Specifically, for flood hazards: (1) To conduct in-depth analysis of extreme precipitation events to assess their spatial variability and projected changes in selected regions across Canada, given that different climatic regimes can respond differently to climate change impact; (2) To test the applicability of commonly used extreme precipitation indices over these regions, and to develop new extreme precipitation indices; (3) To estimate return periods of future extreme storms based on regional IDF curves estimated from simulations of a regional climate model coupled to a land surface model to account for the land-atmosphere feedback and subjected to the latest RCP (Representative Concentration Pathway) climate scenarios of IPCC (2013); (4) To conduct a drought analysis using observed climate data and versatile drought index algorithms for summer over coherent regions of Canada; (5) To understand the impact of climate change to future droughts, selected drought indices will be simulated from RCP climate scenarios statistically or dynamically downscaled for 2050s and 2080s. To simulate the possible combined impact of climate change and El Nio events historically associated with below normal precipitation in western Canada, a bootstrap resampling approach will be used to generate 30-year period datasets adjusted for the combined impact of climate change based on RCP climate scenarios and ENSO using the quantile-quantile mapping method for 2050s and 2080s. The potential impact of climate change to the future water sources of Canadian watersheds dominated by spring snowmelt will be simulated by a hydrologic model forced with downscaled RCP climate scenarios of IPCC (2013). Lastly, adaptation strategies, early warning systems and capacity building measures will be examined to promote preparedness of Canada against climate change impact.