ClimateChange Assessment Guide.pdf - University of Waterloo

Climate Change Assessment49• Planning time horizons are relevant for definingfuture scenarios. Official Plan buildout and maximumpossible buildout are commonly selected land usescenarios for planning studies and hydrologicalinvestigations. Population estimates and water use /water demand estimates are established and used inmodelling these scenarios.• Climate change scenarios are referenced to variousfuture time horizons. Global Climate Model simulationresults are summarized around future time horizonssuch as 2020s, 2050s, 2080s, etc. Scenario designshould match these time horizons so that land use,population, climate and other factors in the study areaare realistic and consistent.6.1.5 Resource Needs – Data and InformationHydrologic studies are constrained by the availabilityof observational data in any of several categoriesincluding meteorology, streamflow, well records, channelgeometry, mapping, etc.Guidance:Potential limiting factors due to data gapsshould be identified at the onset of the study sothat appropriate plans can be implemented toaccommodate or fill these gaps.Data requirements can be substantial requiring time andresources to gather and process and as such, shouldbe carefully planned. A matrix of data needs may helporganize the process of identifying and gatheringdata. The matrix can be populated with relevantinformation regarding data type categories, dataset timeperiods, frequency, format, spatial coverage, domain,costs, availability, quality/completeness and othercharacteristics as required.Hydrologic modellers should, as a matter of duediligence, compile a library of references that provideguidance on parameter selection. These may relate to aparticular model or they may apply generally to physicalchemical-biologicalreactions and processes commonlymodelled. Some example references:• HSP-F Parameter Adjustments to Evaluate the Effectsof Agricultural Best Management Practices (Donigianet al., 1983).• Rates, Constants, and Kinetics Formulations in SurfaceWater Quality Modelling (Second Edition) (Bowie etal., 1985).Other necessary resources include existing models(surface and groundwater) and other software, andsoftware manuals and documentation. Commonlyapplied groundwater models in Ontario include:• FEFLOW; and• MODFLOW.Commonly applied streamflow generation modelsinclude:• HSP-F;• GAWSER; and• SWAT.Other hydrologic models often used in Ontario include:• PRMS;• PC SWMM; and• Visual OttHymo.The U.S. Geological Service (USGS) provides a websitethat offers free downloads of several surface andgroundwater modelling packages, support information,documentation and related information at http://water.usgs.gov/nrp/models.htmlU.The Danish Hydrological Institute also provides surface,groundwater and integrated models for download athttp://www.dhigroup.com/Many proprietary model packages are also available forpurchase.6.1.6 SummaryAfter completing the tasks in this section the modellershould have:• A clear definition of study objectives and desireddeliverables, in conceptual terms;• A definition of the issues of concern, associatedhydrologic processes, and uses/users at risk;• A delineation of study area and areas of concern;