ClimateChange Assessment Guide.pdf - University of Waterloo

Guide for Assessment of Hydrologic Effects of Climate Change in OntarioxviFigure 3.3Figure 5.1Figure 6.1Figure 6.2Figure 6.3Figure 6.4Figure 6.5Figure 6.6Figure 6.7Figure 6.8Figure 6.9Figure 6.10Figure 6.11Fossil CO 2, CH 4and SO 2emissions for six illustrative SRES non-mitigation emission scenarios,their corresponding CO 2, CH 4and N 2O concentrations, radiative forcing and global meantemperature projections based on an SCM tuned to 19 atmosphere-ocean GCMs(Meehl et al., 2007, 803).................................................................................................................................24Monthly change fields for precipitation and air temperature for 2050s in the Credit RiverWatershed as projected by two GCMs (CGCM2 and HadCM3)................................................................36Climate change impact assessment steps...................................................................................................47Left Panel: Global GHG emissions without climate policies using six illustrative SRES scenarios(coloured lines) Right Panel: Solid lines are multi-model global averages of surface warming forscenarios A2, A1B and B1, shown as continuations of the 20th-century simulations. The pink line isnot a scenario, but is for AOGCM simulations where atmospheric concentrations are held constantat year 2000 values. The bars at the right of the figure indicate the best estimate (solid line withineach bar) and the likely range assessed for the six SRES marker scenarios at 2090-2099. Alltemperatures are relative to the period 1980-1999. (Intergovernmental Panel on Climate Change(IPCC), 2007c 7) (Intergovernmental Panel on Climate Change (IPCC), 2007d 7)....................................63Scatter plot of GCM-based mean annual temperature change versus mean annual precipitationchange – 2050s relative to 1961-1990..........................................................................................................71Mean annual water balance estimates from 4 future climates (scatter plot method candidates)..........73Mean annual water balance estimates from 8 future climates (percentile method candidates).............74Mean annual water balance estimates from 57 future climates.................................................................75Mean monthly runoff for silty soils (2050s) for three scenario screening approaches..............................76Histograms illustrate the range of model predictions and likely outcomes.............................................91Flow exceedance charts illustrate the range of flows predicted for each scenario.................................92Histogram of estimated 7Q 20streamflow using 57 climate change scenarios.........................................93Range of Variability of Estimated Streamflow.............................................................................................94List of TablesTable 2.1 Observed changes in global climate relevant to water resources (Bates et al., 2008;Intergovernmental Panel on Climate Change (IPCC), 2001b; Solomon et al., 2007).................................5Table 2.2 Projected changes in global climate for 2090-2099 relative to 1980-1999 using two emissionscenarios (Intergovernmental Panel on Climate Change (IPCC), 2007d)....................................................6Table 2.3 Projected changes in global climate as they relate to water (Bates et al., 2008;Meehl et al., 2007)............................................................................................................................................9Table 2.4 Projected changes in extreme events and their likelihood of occurring(Christensen et al., 2007b).............................................................................................................................10Table 2.5 Climate changes observed and projected for Canada (as summarized in (Bruce et al., 2006b).............12Table 3.1 Characteristics of the SRES storylines (Carter et al., 2007; Nakicenovic et al., 2000)...............................23Table 4.1 Summary of general advantages and disadvantages of GCM-change field, synthetic, analogueand downscaled climates for use in assessments.......................................................................................34Table 5.1 Water Quality Effects of Climate Change....................................................................................................45Table 6.1 Emission scenarios used as “forcings” in the GCM runs for the IPCC AR4..............................................62Table 6.2 The six SRES illustrative scenarios and the stabilization scenarios (parts per million CO 2)they most resemble (IPCC-TGICA et al., 2007; Swart et al., 2002).............................................................63Table 6.3 Scenarios from the Scatter Plot Method .....................................................................................................66Table 6.4 Climate scenarios and rank of mean annual change in temperature and precipitation forthe Percentile Method...................................................................................................................................67Table 6.5 Scenarios selected by the percentiles method using mean annual temperature change field ( o C).......70