Xianfu Lu Climate Scenarios AIACC by dominic.cecilia

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									                           Developing Climate Scenarios for
                       Climate Change I, A & V Assessments
     An introduction to the resources on scenario development and application available for AIACC study teams



By

                  Dr Xianfu Lu, Tyndall Centre for Climate Change Research




At

                                         AIACC Training Workshop on
                              Vulnerability & Adaptation Assessment Methods

                                            3~14 June, Trieste, Italy


                                                      The Tyndall Centre comprises nine UK research institutions.
                                                   It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                                             and receives additional support from the DTI
                   Next 30 minutes…

1. Why do we need climate scenarios?

2. What technical support is available?

3. Why developing climate scenarios are so problematic?

4. What should be considered while developing scenarios?

5. What data are currently available in public domain?

6. What’s new from the technical support group?


                                The Tyndall Centre comprises nine UK research institutions.
                             It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                       and receives additional support from the DTI
1. Why do we need climate scenarios?


                                          Global socio-economic assumptions
  National Policy responses: adaptation



                                                   Emissions scenarios




                                                                                                       Interactions and feedbacks
                                               Concentration projections
             and mitigation




                                             Radiative forcing projections
                                            Sea level               Climate
                                           projections            projections

                                              Climate and Sea Level
                                                    Scenarios
                                          National integrated scenarios (socio-
                                                                                                                                    Conceptual framework for conducting
                                              economic & environmental)                                                             integrated assessment of climate change for
                                                     National impacts                                                               policy applications.
                                                                                                                                    Source: IPCC (2001)

                                                                           The Tyndall Centre comprises nine UK research institutions.
                                                                        It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                                                                  and receives additional support from the DTI
2. What support resource is available?
     • Tyndall Centre
       o   Advising on scenario design;

       o   Providing technical support for scenario development and application;

           •    Preparing technical notes on particular scenario development techniques;

           •    Conducting diagnostic analysis of climate model experiment results while appropriate;

           •    Updating study teams on the newly available information/data


    • Regional mentors
       o   Latin America: Jose Marengo

       o   Asia: Roger Jones

       o   Africa: Bruce Hewittson

                                              The Tyndall Centre comprises nine UK research institutions.
                                           It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                                     and receives additional support from the DTI
3. Why developing climate scenarios are so problematic?


      Problem 1. Models are not accurate ….


        … so we ‘cannot’ use data from climate models directly in
         environmental or social simulation models

          … add model changes to baseline – mean and variability
                       … use a weather generator




                                     The Tyndall Centre comprises nine UK research institutions.
                                  It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                            and receives additional support from the DTI
3. Why developing climate scenarios are so problematic?


    Problem 2. Different climate models give different results …


     … so we have difficulty knowing which climate model(s) to use


      … select on basis of validation, age, representativeness, accessibility – or
                                      use them all!
                                          …




                                        The Tyndall Centre comprises nine UK research institutions.
                                     It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                               and receives additional support from the DTI
3. Why developing climate scenarios are so problematic?


    Problem 3. It is expensive to run many (global/regional)
      climate model experiments for many future emissions ….


    .… so we often have to make choices about which emissions scenarios from
      which we build our climate scenarios

    … may not matter much for 2020s, but will make a real difference by 2080s
    … pattern-scaling methods may help if we only have results from only one
                               emissions scenario




                                       The Tyndall Centre comprises nine UK research institutions.
                                    It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                              and receives additional support from the DTI
3. Why developing climate scenarios are so problematic?



      Problem 4. Climate models give us results at the ‘wrong’
                           spatial scale …


     … so we have to develop and apply one or more downscaling methods

        … these may be simple (interpolation) or complex (statistical
                     downscaling, weather generators)

          … RCMs may get you so far, but probably not far enough



                                     The Tyndall Centre comprises nine UK research institutions.
                                  It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                            and receives additional support from the DTI
4. What should be considered while developing scenarios?


 1)   How many scenarios do you need? Which uncertainties are you going to explore?
 2)   What non-climate information do you need in your scenario(s)?
 3)   Do you need local data for case studies/sites, or national/regional coverage?

 4)   What spatial resolution in your climate model output do you really need – 300k,
      100k, 50k, 10k, 1k? Can you justify this choice?

 5)   Do you need changes in average climate, or in variability?
 6)   Do you need changes in daily weather, or just monthly totals?

 7)   What climate variables are essential for your study?


                                          The Tyndall Centre comprises nine UK research institutions.
                                       It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                                 and receives additional support from the DTI
5. What data are currently available?

   • Data Sources
   1) Climate reconstruction data
      World Data Centre for Palaeo-climatology (www.ngdc.noaa.gov/paleo/data.html)

   2) Observed climatology
      Climatic Research Unit, UEA (www.cru.uea.ac.uk/cru/data)
      NCDC (lwf.ncdc.noaa.gov/oa/ncdc.html)

   3) Climate model outputs
       NCEP/NCAR reanalysis (www.cdc.noaa.gov/cdc/data.nmc.reanalysis.html)
       IPCC-DDC GCM data (ipcc-ddc.cru.uea.ac.uk; ipcc-ddc.cru.uea.ac.uk/dkrz/dkrz_index.html)
       Hadley Centre data (www.cru.uea.ac.uk/link/)
       Canadian data (www.cccma.bc.ec.gc.ca/data.html)

                                            The Tyndall Centre comprises nine UK research institutions.
                                         It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                                   and receives additional support from the DTI
5. What data are currently available?

   • SRES driving GCM experiments
   1) DDC YELLOW pages (ipcc-ddc.cru.uea.ac.uk/dkrz/dkrz_index.html)

       •   Monthly time series (1960~2100);
       •   A set of core surface variables and a set of optional upper-air indices;
       •   Currently available for A2 and B2 runs from HadCM3, CSIRO-Mk2,
           NCAR-PCM, CGCM2); A1 and B1 from CSIRO-Mk2.

   2) DDC GREEN pages (ipcc-ddc.cru.uea.ac.uk)
       •   30-year monthly average (1961~90, 2020s, 2050s, 2080s);
       •   A set of core surface variables and a set of optional upper-air indices;
       •   No data available yet
                                          The Tyndall Centre comprises nine UK research institutions.
                                       It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                                 and receives additional support from the DTI
6. What’s new from the technical support group?
   1) Technical note on pattern-scaling GCM outputs




                                     The Tyndall Centre comprises nine UK research institutions.
                                  It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                            and receives additional support from the DTI
6. What’s new from the technical support group?


   2) Diagnostic analysis of the IPCC TAR reviewed GCM experiments


         •   1961~1990 climatologies against 0.5 degree observed
             climatologies;
         •   Seasonal (DJF and JJA) anomalies of precipitation and
             temperature from 9 GCM experiments for the time slice of 2080s




                                       The Tyndall Centre comprises nine UK research institutions.
                                    It is funded by three Research Councils - NERC, EPSRC and ESRC –
                                              and receives additional support from the DTI
   The Tyndall Centre comprises nine UK research institutions.
It is funded by three Research Councils - NERC, EPSRC and ESRC –
          and receives additional support from the DTI
   The Tyndall Centre comprises nine UK research institutions.
It is funded by three Research Councils - NERC, EPSRC and ESRC –
          and receives additional support from the DTI
   The Tyndall Centre comprises nine UK research institutions.
It is funded by three Research Councils - NERC, EPSRC and ESRC –
          and receives additional support from the DTI
   The Tyndall Centre comprises nine UK research institutions.
It is funded by three Research Councils - NERC, EPSRC and ESRC –
          and receives additional support from the DTI
   The Tyndall Centre comprises nine UK research institutions.
It is funded by three Research Councils - NERC, EPSRC and ESRC –
          and receives additional support from the DTI

								
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