Uncertainty in WRF Regional Model Climate Change Projections For the Great Lakes Basin

Session: 52. - Climate Interactions with Large Lakes? Physical Systems

Fengyi Xie, Department of Physics, University of Toronto, [email protected]
Andre Erler, Aquanty Inc., [email protected]
Richard Peltier, University of Toronto, [email protected]

Abstract

Climate model projections of global warming futures provide a widely employed basis for the assessment of climate change impacts. Assessment of uncertainties in such projections is necessary to characterize the quality of the projection. Here we describe the uncertainty in regional climate change projections in the Great Lakes Basin derivative of differences in the global model which generates the low resolution projection employed to drive the regional model. For this purpose a mini-ensemble of climate change projections has been constructed, in which the WRF regional model, coupled to the Freshwater Lake Model (FLake), is employed to downscale climate change projections produced using output from several global models that were exercised in Phase 5 of the Coupled Model Intercomparison Project (CMIP5). All global models were run under the IPCC Representative Concentration Pathways 8.5 Scenario for greenhouse gas increase. Results from this mini-ensemble are first verified with instrumental observations for the historical period (1979-1989), following which future climate projections are produced for periods of either moderate (2050-2060) or severe (2085-2100) climate change expectations. By employing the same WRF configuration in the downscaling process we are able to isolate the contribution to uncertainty due to difference in the low resolution parent model.

1. Keyword
global warming

2. Keyword
Great Lakes basin

4. Additional Keyword
Dynamical Downscaling