ClimateChange Assessment Guide.pdf - University of Waterloo

Climate Change Assessment91charts illustrate the percentage of time, or probability,that flow rates are expected to be exceeded and havedifferent shapes depending on the type of hydrological,hydrogeological, and land use characteristics.Overlaying the flow exceedance charts for each of thefuture climate scenarios, as shown on Figure 6.9, canhelp visualize hydrologic impacts.Table 6.10 Example comparison of hydrologic metrics for climate change scenariosHydrologicImpactMetricMean AnnualFlow (m 3 /s)2-Year (1 Day)(m 3 /s)50-Year(1 Day) (m 3 /s)Ref.RegimeFuture Climate ScenarioAggregated Results1 2 3 4 5 Median Minimum Maximum12 12.5 11.2 10.9 13.1 11.9 11.9 / 99% 10.9 / 91% 13.1 / 109%20 20.4 18.3 17.8 21.4 19.4 19.4 / 97% 17.8 / 89% 21.4 / 107%29 31.7 28.4 27.7 33.2 30.2 30.2 / 104% 27.7 / 95% 33.2 / 115%7Q 10(m 3 /s) 4 3.9 3.5 3.4 4.1 3.7 3.7 / 93% 3.4 / 85% 4.1 / 103%7Q 20(m 3 /s) 3 2.9 2.6 2.5 3.0 2.7 2.7 / 91% 2.5 / 84% 3.0 / 100%FrequencyOverbank(1/year)1.9 2.0 2.2 1.7 2.4 1.6 2.0 / 105% 1.6 / 84% 2.4 / 126%Figure 6.8 Histograms illustrate the range of model predictions and likely outcomes