Global climate model scenarios downscaled for Canada David Price Northern Forestry Centre, Edmonton CIF e-Lecture, 14 March 2012
Slide 2 Acknowledgements Dan McKenney Canadian Centre for Climate Modelling and Marty Siltanen Analysis (CCCMA) Pia Papadopol US National Center for Atmospheric Research (NCAR) Kevin Lawrence G. Strand (UCAR) John Pedlar Australia: Commonwealth Scientific and Industrial Research Organisation (CSIRO) Kathy Campbell M. Collier, M. Dix, and T. Hirst (CSIRO Marine and Atmospheric Yonghe Wang Research Division) (all the above are with CFS) Japan: Center for Climate System Research, Mike Hutchinson University of Tokyo, National Institute for ( Australian National University, Canberra) Environmental Studies, Frontier Research Linda Joyce Center for Global Change Many reviewers in Canada and the USA of (USDA Forest Service, Ft Collins CO) two reports published in 2011. Dave Coulson (USDA Forest Service, Ft Collins CO) Downscaled climate scenarios for Canada - 14 March 2012
Slide 3 Outline Techniques: Downscaling and ANUSPLIN Selecting GCMs and GHG scenarios Results Maps Graphs Sample applications Testing the climate models Biophysical variables and moisture indices Concluding remarks Publications & data distribution Downscaled climate scenarios for Canada - 14 March 2012
Slide 4 Outline Techniques: Downscaling and ANUSPLIN Selecting GCMs and GHG scenarios Results Maps Graphs Sample applications Testing the climate models Biophysical variables and moisture indices Concluding remarks Publications & data distribution Downscaled climate scenarios for Canada - 14 March 2012
Slide 5 What is Downscaling? ―D ownsca ling‖ is using coarse spatial resolution data to generate information that is more useful at smaller scales Dynamical: physically consistent simulations of weather at GCM timesteps but at higher spatial resolution. RCMs are the prime example. Statistical: many methods to relate GCM results to observed weather and climate. Spatial interpolation: relatively simple and largely empirical, but robust! Diagram from: D. Viner, CRU, University of East Anglia Downscaled climate scenarios for Canada - 14 March 2012
Slide 6 About ANUSPLIN Mike Hutchinson at Australian National University (Canberra) FORTRAN program for application of multi-variate thin-plate splines (typically up to 4 independent variables, more covariates) Most applications routinely incorporate a spatially (and temporally) varying dependence on elevation A key element is that ANUSPLIN minimizes General Cross Validation (GCV) statistic – an objective method to select the best interpolation models, optimize data smoothing, and provide estimates of predictive error Diagnostics help to identify data errors ANUSPLIN continually being updated Check out http://fennerschool.anu.edu.au/publications/software/anusplin.php Numerous applications worldwide, many independent of Hutchinson’s group Lots of references available: see CFS GLFC web site for a list and links: http://cfs.nrcan.gc.ca/subsite/glfc-climate Downscaled climate scenarios for Canada - 14 March 2012
Slide 7 Normalizing the GCM data Ideally, we want to capture the climate change signal generated by the GCM, but corrected for the GCM’s ―ina ccuraci es‖ in representing reality We use the ― Delta m ethod‖, base d on a reference period for which we also have observed data (e.g., 1961-1990) Interpolated long-term monthly means (30-year ― normals‖) provide a reference data set with spatial detail We then add the change signal (i.e., the temperature difference) to the observed climate normals for the reference period, interpolated to the same coordinates. Requires processing of GCM data to convert them to deltas WRT the same period in the simulation . Downscaled climate scenarios for Canada - 14 March 2012
Slide 8 Correcting for GCM ―inac curacy ‖ Step 1: Determine mean of observations for reference period. Downscaled climate scenarios for Canada - 14 March 2012
Slide 9 Correcting for GCM ―inac curacy ‖ Step 1: Determine mean of observations for reference period. Step 2: Determine mean of GCM projection for reference period. Downscaled climate scenarios for Canada - 14 March 2012
Slide 10 Correcting for GCM ―inac curacy ‖ Step 1: Determine mean of observations for reference period. Step 2: Determine mean of GCM projection for reference period. Step 3: Calculate delta values by subtracting (or dividing by ) the GCM mean from Step 2 Downscaled climate scenarios for Canada - 14 March 2012
Slide 11 Correcting for GCM ―inac curacy ‖ Step 1: Determine mean of observations for reference period. Step 2: Determine mean of GCM projection for reference period. Step 3: Calculate delta values by subtracting (or dividing by ) the GCM mean from Step 2 Step 4: Calculate corrected GCM data by adding (or multiplying by ) the observed mean from Step 1 Downscaled climate scenarios for Canada - 14 March 2012
Slide 12 Selected GCM Scenarios Projection data generated by GCMs from CCCma (Canada), CSIRO (Australia), NCAR (USA) and NIES (Japan). [Data also available from IPCC 3 rd Assessment (TAR, 2001) (CCCma, CSIRO, Hadley Centre (UK) and NCAR.] SRES A2: increasing population, little technological change, greater deforestation, pollution and CO 2 emissions SRES B1: as A2, but rapid global shift towards resource-efficient technologies and reduced GHG emissions SRES B2: as B1, but more local efforts to increase resource efficiency and reduce emissions SRES A1B: higher population growth than A2, with balance of energy from fossil and renewable sources Monthly time series extending from 1961 to 2100, gridded to 5 arcminute (1/12 degree lat/lon) resolution – about 10 km. 20 data sets in total. Lots of ways to use these data! Nakićenović et al. 2000. IPCC Special Report on Emissions Scenarios. Downscaled climate scenarios for Canada - 14 March 2012
Slide 13 IPCC AR4 GHG Scenarios Downscaled climate scenarios for Canada - 14 March 2012
Slide 14 GCM spatial resolutions vary Downscaled climate scenarios for Canada - 14 March 2012
Slide 15 GCM input data sets GCM 1 IPCC AR4 Monthly variable(s) 2 Source 3 Time period scenario(s) CGCM31MR 20C3M, A1B, pr, tas, rsds, hur, huss, psl, uas, CMIP3 1961–2100 A2, B1 vas CGCM31MR 20C3M, A1B, tasmin, tasmax CCCma 1961–2100 A2, B1 CSIROMK35 20C3M, A1B, pr, tas, tasmin, tasmax, rsds, psl, CMIP3 1961–2100 A2, B1 uas, vas, hur, huss (except B1) CSIROMK35 B1 huss CSIRO 2001–2100 MIROC32MR 20C3M, A1B, pr, tas, tasmin, tasmax, rsds, hur, CMIP3 1961–2100 A2, B1 huss, psl, uas, vas NCARCCSM3 20C3M, A1B, pr, tas, tasmin, tasmax, rsds, hur, CMIP3 1961–2099 B1 huss, psl, uas, vas NCARCCSM3 A2 pr, tas, tasmin, tasmax, rsds, ESG 1961–2099 hur, huss, psl, uas, vas Downscaled climate scenarios for Canada - 14 March 2012
Slide 16 Outline Techniques: Downscaling and ANUSPLIN Selecting GCMs and GHG scenarios Results Maps Graphs Applications Testing the climate models Biophysical variables and moisture indices Concluding remarks Publications & data distribution Downscaled climate scenarios for Canada - 14 March 2012
Slide 17 Projected changes in T max These maps show ―ab solute ‖ temperatures. It is very hard to see the changes over 100+ simulated years! Downscaled climate scenarios for Canada - 14 March 2012
Slide 18 Projected changes in Precip These maps show ―ab solute ‖ total annual precipitation. Again, it is very hard to see the changes over 100+ simulated years! It would be just as hard to see differences among different GCMs when forced by the same GHG emissions scenario. Downscaled climate scenarios for Canada - 14 March 2012
Changes in annual means Slide 19 (SRES A2, 2080s) CGCM3.1 - Canada CSIRO Mk 3.5 - Australia MIROC3.2 - Japan NCAR CCSM3 - USA Precipitation Change (ratio) Temperature Increase (°C) Downscaled climate scenarios for Canada - 14 March 2012
Slide 20 Analysis by Canadian ecozones Downscaled climate scenarios for Canada - 14 March 2012
Annual Mean Daily T min Slide 21 Prairies subhumid ecozone (Parkland) Temperature (°C) (Historical data ~45 years) Downscaled climate scenarios for Canada - 14 March 2012
Winter (DJF) Mean Daily T min Slide 22 Boreal Plains ecozone Temperature (°C) Downscaled climate scenarios for Canada - 14 March 2012
Summer (JJA) Mean Daily T max Slide 23 Atlantic Maritime ecozone Temperature (°C) Downscaled climate scenarios for Canada - 14 March 2012
Summer (JJA) Mean Vapour Pressure Slide 24 Atlantic Maritime ecozone Vapour pressure (kPa) (No historical record) Downscaled climate scenarios for Canada - 14 March 2012
Fall (SON) Total Precipitation Slide 25 Mixedwood Plains ecozone Total Precipitation (mm) Downscaled climate scenarios for Canada - 14 March 2012
Winter (DJF) Mean Daily Solar Radn Slide 26 Boreal Shield W ecozone (No historical record) MJ m -2 day -1 M Downscaled climate scenarios for Canada - 14 March 2012
Winter (DJF) Mean Daily Solar Radn Slide 27 Boreal Shield W ecozone MJ m -2 day -1 10-year moving averages Downscaled climate scenarios for Canada - 14 March 2012
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