The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada Downscaling Tools Introduction to LARS-WG and SDSM

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada LARS-WG stochastic weather generator ( ) Generation of long weather time-series suitable for risk assessment Ability to extend the simulation of weather to unobserved locations A computationally inexpensive tool to produce climate change scenarios incorporating changes in means and in variability

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada LARS-WG stochastic weather generator ( ) Generates precipitation, min and max temperature and solar radiation Modelling of precipitation events is based on wet/dry series Semi-empirical distributions are used for precipitation amounts, dry/wet series and solar radiation Temperature and solar radiation are conditioned on the wet/dry status of a day Temperature and solar radiation are cross-correlated Parametric- e.g., WGENSemi-parametric - e.g., LARS-WG

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada LARS-WG Model calibration - SITE ANALYSIS Model validation - QTEST Generation of synthetic weather data - GENERATOR

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada SITE ANALYSIS

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada QTEST Compare observed and synthetic data to evaluate LARS-WG performance

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada Base scenario file GENERATOR Generate synthetic weather data: to extend time series, or for climate change studies Scenario file

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada GENERATOR

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada Limitations of LARS-WG (and weather generators in general)... Temporal downscaling only Designed for use at individual sites only (no spatial correlation) Can only represent events in calibration data set Generally underestimate variability

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada SDSM 1.A decision support tool for assessing local climate change impacts 2.Facilitates the rapid development of multiple, low-cost, single-site scenarios of daily surface weather variables under current and future climate forcing 3.Based on a multiple regression-based method

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada SDSM Structure 7 steps: Quality Control and Data Transformation Screening of Predictor Variables Model Calibration Weather Generation (using observed predictors) Statistical Analyses Graphing Model Output Scenario Generation (using climate model predictors)

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada

Model Verification

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada

Tmax > 25°C

The Canadian Climate Impacts Scenarios (CCIS) Project is funded by the Climate Change Action Fund and provides climate change scenarios and related information to the VIA community in Canada

Cautionary Remarks SDSM provides a parsimonious technique of scenario construction that complements other methods SDSM should not be used uncritically as a black box (evaluate all relationships using independent data) Local knowledge is an invaluable source of information when determining sensible combinations of predictors Daily precipitation amount at individual stations is the most problematic variable to downscale The plausibility of all SDSM scenarios depends on the realism of the climate model forcing Try to apply multiple forcing scenarios (via different GCMs, ensemble members, time–slices, emission pathways, etc.)