Representing Uncertainties & Selecting Scenarios

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					   Operationalising Coping Ranges
climate sensitivity, coping ranges and risk


  AIACC Training Workshop on Adaptation and Vulnerability
                     TWAS, Trieste
                     June 3-14 2002




                        Roger N. Jones




                                               Atmospheric Research
                     Choices

• Roundtable of project needs regards coping ranges,
  thresholds, climate risk and uncertainty management
• Choosing climate variables/sensitivity relationships
  (exercise)
• How to construct thresholds
• Structure of climate probabilities (variability and
  change, short exercise)
• Case studies
   – hot cows (heat stress and adaptation)
   – water resources (Monte Carlo uncertainty and
      Bayesian analysis
   – risk as a function of global warming


                                              Atmospheric Research
         Sensitivity to what?

Sector         Sensitivity to what?
Water          Rainfall variability, flood, drought

Agriculture    ENSO, flood, drought, cool/hot
               extremes, storms
Health         Hot/wet conditions, temperature
               extremes, violent storms, floods, crop
               and water shortages
Coasts         Storm surges, wind/wave climates,
               pressure extremes, tidal extremes
Biodiversity Fire, flood, drought, storms

                                          Atmospheric Research
      Linking climate to impacts


                                Socio-
Climate       Impacted
                               economic
system         activity
                                system

Current                 Current
climate               adaptations


Future                  Future
climate               adaptations

                              Atmospheric Research
                                           Cross impacts analysis




                                                                                                                                                                                            Dryland/irrigation salinity




                                                                                                                                                                                                                                                                                               Industry, coal & power
                                                                                Marine (esp. fisheries)


                                                                                                                  Coastal water supply




                                                                                                                                                                                                                          Forest & biodiversity
                                                                                                                                                                                                                                                  Urban infrastructure
                                                                                                                                                   Inland water supply
                                                                                                                                                                         River management




                                                                                                                                                                                                                                                                         Air quality
                                                     Cropping




                                                                                                                                         Harbour
                                           Grazing




                                                                       Horses
                         Poultry




                                                                                                                                                                                                                                                                                                                        Health
                                                                                                          Beach




                                                                                                                                                                                                                                                                                       Waste
                                   Dairy




                                                                Wine
                                                                                                                                                                                                                                                                                                                                           Workshop
Rainfall - average                 2       1         2          2                                                 1                                3                     2                  2                             2                       2                      1                                              1        21
Rainfall - extreme
Rainfall - variability
                                   1
                                   2
                                           2
                                           3
                                                     2
                                                     3
                                                                1
                                                                2
                                                                       1        1
                                                                                2
                                                                                                          2       2
                                                                                                                  1
                                                                                                                                                   2
                                                                                                                                                   3
                                                                                                                                                                         3
                                                                                                                                                                         3
                                                                                                                                                                                            3
                                                                                                                                                                                            1
                                                                                                                                                                                                                          2
                                                                                                                                                                                                                          1
                                                                                                                                                                                                                                                  3
                                                                                                                                                                                                                                                  2
                                                                                                                                                                                                                                                                                       2       2                        1        30
                                                                                                                                                                                                                                                                                                                                 23
                                                                                                                                                                                                                                                                                                                                             Report
Drought
Temperature - average    1
                                   2
                                   2
                                           3
                                           1
                                                     3
                                                     2
                                                                2
                                                                2
                                                                       1        1
                                                                                2
                                                                                                                  2
                                                                                                                                         1
                                                                                                                                                   3                     2
                                                                                                                                                                         2
                                                                                                                                                                                            2
                                                                                                                                                                                            1
                                                                                                                                                                                                                          3
                                                                                                                                                                                                                          2                                              2             1
                                                                                                                                                                                                                                                                                               2                        2
                                                                                                                                                                                                                                                                                                                        1
                                                                                                                                                                                                                                                                                                                                 28
                                                                                                                                                                                                                                                                                                                                 20
                                                                                                                                                                                                                                                                                                                                           (example)
Temperature - max        3         2       2         2                 2        1                                                                                        3                                                1                       3                                    2       1                        2        24
Temperature - min                  2       2         2          2      2                                                                                                                                                  1                       2                                    1       1                        1        16
CO2                                2       2         2          2      1                                                                                                                                                  2                                                                                                      11
Cloud                                                1                                                                                                                                                                                            1                      1                                                       3
Pressure                                                                                                                                                                                                                                                                 1                                                       1
Humidity                 2         1                            2                                                                                                                                                         1                       2                                            1                        1        10
Wind                               1       1         1          1               1                         2                              2                                                                                1                       2                      2                     2                                 16
Evaporation
Soil moisture
                         2
                                   3       3         3          3      2
                                                                                1                                                                  2
                                                                                                                                                   1
                                                                                                                                                                         1                  2                             1
                                                                                                                                                                                                                          2                       1
                                                                                                                                                                                                                                                                                       1
                                                                                                                                                                                                                                                                                       2
                                                                                                                                                                                                                                                                                                                                 10
                                                                                                                                                                                                                                                                                                                                 20
                                                                                                                                                                                                                                                                                                                                            Worked
Stream flow                                                                     2                                 1                                3                     3                  2                             1                       1                                            3                        1        17
Flood                              2       1         1          1      1        1                                                        3         2                     3                  2                             1                       3                                    3       3                        2        29        example in
Watertable                                                                      2                                 3                                1                     1                  1                             1                       1                                    2                                         12
Water salinity                                       1          1               1                                 3                                2                     2                  3                             1                                                                    2                        1        17        MS Excel®
Irrigation                         2       1         2          3                                                                                  2                     2                  1                                                                                                                                    13
Sea level                                                                       1                         3       3                      3                                                                                                        2                                                                              12
Storm surge                                                                                               3                              3                                                                                                        1                                                                              7
Waves                                                                           2                         3       1                      2                                                                                                                                                                                       8
Lightning                                                         1                                                                                                                                                                               1          1                                                                   3
Hail                                   3             2                                                                                                                                                                                            2                                                                              7
Fire                             1     1 1                        3                                                                                                                                                                               1 2     1 2                                                                    12
                            8 24 23 29 28 11 18 13 17 14 24 27 20 27                                                                                                                                                                              30 9 14 18 16


                                                                                                                                                                                                                                                                                                                                      Atmospheric Research
           Cross impacts analysis
             Climate and related variables   Activities
             (forcing)                       (sensitivity)
High         Rainfall - extreme              Urban infrastructure
             Flood                           Cropping
             Drought                         Wine
             Temperature - max               River management
             Rainfall - variability          Forest & biodiversity
             Rainfall - average              Inland water supply
             Temperature - average           Dairy
             Soil moisture                   Grazing
                                             Dryland/irrigation salinity
Moderate     Stream flow                     Industry, coal & power
             Water salinity                  Marine (esp. fisheries)
             Temperature - min               Coastal water supply
             Wind                            Health
             Irrigation                      Harbour
             Watertable                      Waste
             Sea level                       Beach
             Fire                            Horses
             CO2
             Humidity
             Evaporation
Low          Waves                           Air quality
             Storm surge                     Poultry
             Hail
             Cloud
             Lightning
             Pressure

                                                                Atmospheric Research
Uncertainty explosion

                     Emission scenarios

                  Global climate sensitivity

                    Regional changes

                    Climate variability

                    Biophysical impacts

                  Socio-economic impacts



                        Atmospheric Research
Uncertainty explosion


                     Emission scenarios

                  Global climate sensitivity

                    Regional variability

                    Biophysical impacts

                  Socio-economic impacts




                        Atmospheric Research
                Likelihood

Probability can be expressed in two
   ways:
1. Return period / frequency-based
   (Climate variability)
2. Single event
   (Mean climate change, one-off events)




                                      Atmospheric Research
   Return period / frequency-based
             probability

Recurrent or simple event
Where a continuous variable reaches a critical level, or
   threshold.
Eg. Extreme temperature (max & min), Extreme rainfall,
   heat stress, 1 in 100 year flood
Discrete or complex event
An event caused by a combination of variables (an
   extreme weather event)
Eg. tropical cyclone/hurricane/typhoon, ENSO event




                                               Atmospheric Research
Frequency-based probability
       distributions




                        Atmospheric Research
         Single-event probability

Singular or unique event
An event likely to occur once only. Probability refers to
   the chance of an event occurring, or to a particular
   state of that event when it occurs.
Eg. Climate change, collapse of the West Antarctic Ice
   Sheet, hell freezing over




                                                 Atmospheric Research
    What is the probability of climate
                 change?

1. Will climate change happen?
•   IPCC (2001) suggests that climate change is occurring with
    a confidence of 66% to 90%
2. What form will it take?
Uncertainties are due to:
• future rates of greenhouse gas emissions
• sensitivity of global climate to greenhouse gases
• regional variations in climate
• decadal-scale variability
• changes to short-term variability




                                                      Atmospheric Research
                 Range of uncertainty




                  M1            M2    M3      M4


UNQUANTIFIABLE                                              UNQUANTIFIABLE
 UNCERTAINTY
                   QUANTIFIABLE RANGE OF UNCERTAINTY
                                                             UNCERTAINTY


                       TOTAL RANGE OF UNCERTAINTY




                                                    Atmospheric Research
CO2 emissions and concentrations




                           Atmospheric Research
Simulated global warming: A2




                         Atmospheric Research
Global warming




                 Atmospheric Research
  Group exercise - estimating joint
           probabilities

• Take a gold coin (preferably 1 pound coin)
• Heads represents low end (1.4°C), tails
  represents high end (5.8°C)
• Flip coin 7 times and record the number of
  heads and tails
• Which outcome is most likely?




                                      Atmospheric Research
     Risk exercise - conclusion

• Give coin to greedy presenter




                                  Atmospheric Research
              Probabilistic structure of climate
                        uncertainties



                  Critical threshold
Variable(s)




                 Critical threshold
                                         Planning horizon
                                  Time
                                                     Atmospheric Research
           Placing thresholds within scenario
                       uncertainty



                                                                   A

                                                                   B
global climate      emission        regional              range of
                                                   
  sensitivity        scenarios       variability        possible impacts




                                                       Atmospheric Research
                                                  Impact thresholds
Threshold
examples                          4.0
   &
                                  3.5
workshop
            Global Warming (°C)




                                  3.0
synthesis
                                  2.5

                                  2.0                                              Threshold A

                                  1.5

                                  1.0

                                  0.5
                                                                                   Threshold B
                                  0.0
                                    1990 2000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100
                                                               Year




                                                                                     Atmospheric Research
      Metrics for measuring costs

•   Monetary losses (gains)
•   Loss of life
•   Change in quality of life
•   Species and habitat loss
•   Distributional equity




                                Atmospheric Research
            System responses

• Resistance (e.g. seawall)
• Resilience (e.g. regrowth, rebuilding after
  storm or fire)
• Adaptation (adjustments made in response to
  stress)
• Transformation (old system stops, new one
  starts)
• Cessation (activity stops altogether)


                                          Atmospheric Research
      Hot cows and heat stress
THI between 72 and 78   THI between 79 and 88




    mild stress           moderate stress


THI between 89 and 98       THI above 98




   severe stress           DEAD COWS!

                                   Atmospheric Research
                                     Frequency of exceeding
Threshold
                                       heat index threshold
examples
                        90.0
   &
workshop
synthesis               80.0
                                                                                                   THI78
            THI Units




                                                                                                   THI72
                        70.0



                        60.0



                        50.0
                          1/10/98   31/10/98   30/11/98   30/12/98   29/01/99   28/02/99     30/03/99
                                                           Date




                                                                                           Atmospheric Research
                     Production effects
Powerpoint
                            THI between 72 and 78




 Report


              mild stress                           no stress

                            THI between 79 and 88




             moderate stress                        mild stress

                                                           Atmospheric Research
          Coral bleaching

• Caused by SST above a threshold
• Expels xosanthellae algae
• Severity related to days above
  bleaching threshold
• Corals may recover or die




                               Atmospheric Research
               Macquarie River Catchment
                                               Area ~ 75,000 km2
                                               P = 1000 to <400 mm.

Macquarie                                      Major dams: Burrendong and
Marshes
                                                Windamere
                        Major Areas of         Water demands: irrigation
                        Abstraction
                                                agriculture; Macquarie
                                                Marshes; town supply
                                               Most flow from upper
                             Macquarie R
                             Contributing
                                                catchment runoff
   Burrendong Dam            Area
                                               Most demand in the lower
                                                catchment
             Windamere Dam




                                                          Atmospheric Research
 Ranges of seasonal rainfall change
           for the MDB
Summer      Winter




                       -40    -20      0     20    40
                             Rainfall Change (%)
                                  2030
                                  2070




Autumn      Spring     -40    -20      0     20    40
                             Rainfall Change (%)


                                     Atmospheric Research
                                       P and Ep changes for Macquarie
                                                 catchment
  Change for 1ºC global warming (%)   16.0



                                       8.0



                                       0.0



                                       -8.0



                                      -16.0
                                              J   F   M   A     M      J         J      A       S       O    N     D
                                                              Evaporation (Ep)       Rainfall (P)
In change per degree global warming
                                                                                                    Atmospheric Research
Changes to MAF for 9 models in 2030 (%)
          Based on IPCC 2001
            Low         Mid           High
        0          0             0


       -8          -8
                                -10

      -16         -16

                                -20
                  -24


                                -30
 B1 at 1.7°C      A1 at 2.5°C         A1T at 4.2°C
  0.55°C           0.91°C               1.27°C
                                             Atmospheric Research
Climate change – flow relationship




flow = a  ( atan (Ep / P ) – b

Standard error < 2%




                                     Atmospheric Research
             Sampling strategy

• The range of global warming in 2030 was 0.55–
  1.27°C with a uniform distribution. The range of
  change in 2070 was 1.16–3.02°C.
• Changes in P were taken from the full range of
  change for each quarter from the sample of nine
  climate models.
• Changes in P for each quarter were assumed to be
  independent of each other
• The difference between samples in any consecutive
  quarter could not exceed the largest difference
  observed in the sample of nine climate models.
• Ep was partially dependent on P (dEp = 5.75 –
  0.53dP, standard error = 2.00, randomly sampled
  using a Gaussian distribution)
                                             Atmospheric Research
Changes to Burrendong Dam storage
               2030
                                   15                                                       Cumulative
Potential evaporation change (%)              -40        -30       -20       -10            Probability (%)

                                                                                                <100
                                                                                   0
                                   10
                                                                                                <95

                                                                                                <90
                                   5                                               10

                                                                                                <80

                                   0                                                            <70
                                                                                   20
                                                                                                <60

                                   -5                                                           <50
                                        -10         -5         0         5             10
                                                    Rainfall change (%)



                                                                                             Atmospheric Research
                                    Changes to bulk allocations for
                                           irrigation 2030
                                   15                                          Cumulative
Potential evaporation change (%)              -30          -20
                                                                     -10
                                                                               Probability (%)

                                                                                   <100
                                   10
                                                                                   <95
                                                                      0
                                                                                   <90
                                   5
                                                                                   <80
                                                                     10
                                   0                                               <70

                                                                                   <60

                                   -5                                              <50
                                        -10   -5       0         5        10
                                              Rainfall change (%)



                                                                                Atmospheric Research
                                        Changes to Macquarie Marsh
                                               inflows 2030
                                   15                                               Cumulative
Potential evaporation change (%)              -40         -30       -20
                                                                          -10       Probability (%)

                                                                                        <100
                                   10
                                                                           0            <95

                                                                                        <90
                                   5
                                                                          10
                                                                                        <80

                                   0                                                    <70
                                                                          20
                                                                                        <60

                                   -5                                                   <50
                                        -10         -5          0     5        10
                                                    Rainfall change (%)



                                                                                     Atmospheric Research
Probabilities of flow changes -
        impacts view
       Range of possible outcomes




                                    Atmospheric Research
        Critical thresholds
     Macquarie River Catchment

Irrigation
5 consecutive years below 50% allocation of
   water right


Wetlands
10 consecutive years below bird breeding
   events




                                       Atmospheric Research
                     Irrigation allocations and wetland inflows
                          - historical climate and 1996 rules

                 10,000,000                                                      100




                                                                                       Irrigation allocation (%)
                                                                                 80
Flow (Gl x 10)




                  1,000,000
                                                                                 60


                                                                                 40
                   100,000

                                                                                 20


                    10,000                                                       0
                          1890   1910   1930          1950       1970     1990
                                               Year
                                        Allocations    Marshes



                                                                        Atmospheric Research
Threshold exceedance as a function
   of change in flow (irrigation)
  Sequences below                 Change in mean average allocation
   threshold (years)      +5%   0     -10%     -15%     -30%      -40%   -45%
          16
          15                                                              1
          14                                                              1
          13                                                              1
          12                                                              1
          11                                                      1       0
          10                                                      1       1
           9
           8
           7                                                              1
           6                                              1       1
           5                                     2        2               1
           4                             2                2       4       5
           3              1     1        1      2         4       1       1
           2              5     4        6      6         5       6       2
           1              10    13      11      12        7       4       4
 Percent of total years
                          22    23      34      38       50       58      64
    below threshold


                                                         Atmospheric Research
Threshold exceedance as a function
 of change in flow (bird breeding)
  Sequences below                       Change in MAF
   threshold (years)      +5%   0    -10%   -15%    -30%   -40%   -50%
          16                                                        1
          15                                         1      1       2
          14                                         1      1       2
          13                                         1      2       3
          12                                         1      2       3
          11                          1       1
          10                                  1      1      1      1
           9
           8                    1
           7               1    1     1                            1
           6                                                2      1
           5               1    1     1       1      2      1
           4               3    2     2       3      4      2      3
           3               2    1     3       4      3      3      1
           2               4    7     4       2      2             1
           1               4    3     7       5      3      3
 Percent of total years
                          40    45    52     56     63      71     79
    below threshold

                                                     Atmospheric Research
                         Risk analysis results
Report                     Macquarie 2030
                                              DDR           N or m a l        FD R
         100




                                                                                              C um u la tiv e P rob ability
          90
          80
          70
          60
          50
          40
          30
          20
          10
           0
               20   10        0               -10              -20            -30       -40
                                  C ha nge in sup ply (% )
                           B u r ren d on g    M a rsh es      Irr ig ation




                                                                               Atmospheric Research
            Risk analysis results
              Macquarie 2070
                   DDR Normal FDR
100
90
80




                                                                    Cumulative Probability
70
60
50
40
30
20
10
 0
      40   20    0           -20        -40          -60      -80
                     Change in supply (%)
                Burrendong    Marshes   Irrigation




                                                           Atmospheric Research
           Bayesian analysis results
              Macquarie 2030
100
90
80




                                                                       Cumulative Probability
70
60
50
40
30
20
10
 0
      20    10   0           -10           -20         -30       -40
                     Change in supply (%)
                 Standard    W&R warming         All




                                                             Atmospheric Research
           Bayesian analysis results
              Macquarie 2070
100
90
80




                                                                       Cumulative Probability
70
60
50
40
30
20
10
 0
      40    20   0           -20           -40         -60       -80
                     Change in supply (%)
                 Standard    W&R warming         All




                                                             Atmospheric Research
Characterising risk as a function of
         global warming

The standard “7 step method” of impact
  assessment progresses from climate to
  impacts to adaptation. This infers that we
  must predict the likeliest climate before we
  can predict the likeliest impacts.

Can we get around this limitation?




                                        Atmospheric Research
           Characterising risk

There is another way.

     Impacts = function(Global warming)

 Impacts = function(global, local CC & CV )

p(impacts) = no. of scenarios > threshold = risk




                                        Atmospheric Research
Risk exercise - estimating threshold
     exceedance: sea level rise

• Recover coin from greedy presenter
• Heads represents low end (9 cm), tails
  represents high end (88cm)
• The group chooses two critical thresholds
• Flip coin 7 times and record the number of
  heads and tails
• Which outcome is most likely?




                                       Atmospheric Research
                              Characterising the risk of global
                                         warming
                      6                                                           6




                                                                                                                    Probability of threshold
                      5                                                           5




                                                            Global warming (°C)
Global warming (°C)




                                                                                                                        exceedance
                      4                                                           4

                      3                                                           3

                      2                                                           2

                      1                                                           1

                      0                                                           0
                          0     1      2    3       4   5                             0        50           100
                                    Frequency (%)                                         Frequency (%)


                      Increasing likelihood of
                          global warming
                                                                                                    Atmospheric Research
                                                                                                                          100                                                            100


                                                                                                                          80                                                             80
                                                                                                                                               75 cm                                                         75 cm
                       75 cm




                                                                                                    Sea Level Rise (cm)




                                                                                                                                                            Sea Level Rise (cm)
                                                                                                                          60                                                             60

                       50 cm                                                                                                                   50 cm                                                         50 cm


                                                                                                                          40                                                             40


                       25 cm                                                                                                                   25 cm                                                         25 cm
                                                                                                                          20                                                             20


                                                                                                                           0                                                              0
                                                                                                                                0                 100                                          0                100
                                                                                                                                Probability (%)                                                Probability (%)

                      100                                                 100                                             100                                                            100


                      80                                                  80                                              80                                                              80
Sea Level Rise (cm)




                                                    Sea Level Rise (cm)




                                                                                                    Sea Level Rise (cm)




                                                                                                                                                                   Sea Level Rise (cm)
                                           75 cm                                           75 cm                                               75 cm                                                          75 cm



                      60                                                  60                                              60                                                              60

                                           50 cm                                           50 cm                                               50 cm                                                          50 cm

                      40                                                  40                                              40                                                              40


                                           25 cm                                           25 cm                                               25 cm                                                          25 cm
                      20                                                  20                                              20                                                              20


                       0                                                   0                                               0                                                               0
                            0         5        10                               0             100                               0         5            10                                      0                 100
                                Probability (%)                                 Probability (%)                                     Probability (%)                                                Probability (%)
                                             Characterising the risk of global
                                                        warming
Probability of threshold                         6

                                                 5

                           Global warming (°C)
                                                                               Risks to Large Negative   Net    Higher
                                                                                Many Increase for most Negative
                                                 4
    exceedance

                                                                                               regions  in all
                                                                                                       metrics
                                                 3

                                                                                                             Markets
                                                 2
                                                                                                             + and -

                                                 1                                                             Most
                                                                                              Negative        people
                                                                               Risks to       for some        worse     Very
                                                 0                              Some Increase regions           off     low

                                                     0        50         100
                                                         Frequency (%)
                                                                                 I          II       III       IV        V

                                                                               I     Risks to unique and threatened systems
                                                                               II    Risks from extreme climate events
                                                                               III   Distribution of impacts
                                                                               IV     Aggregate impacts
                                                                               V     Risks from large-scale discontinuities

                                                                                                  Atmospheric Research
        Long-term planning
     Short-term policy response

1. Enhance adaptive capacity so that the
   current coping range expands,
   reducing present vulnerability.
2. Develop this capacity in such a way
   that the longer-term risks to climate
   change are also reduced.




                                  Atmospheric Research
               Basic principles

• Pay greater attention to recent climate experience. Link
  climate, impacts and outcomes to describe the coping range.
• Address adaptation to climate variability and extremes as part
  of reducing vulnerability to longer-term climate change.
• Assess risk according to how far climate change, in
  conjunction with other drivers of change, may drive activities
  beyond their coping range.
• Focus on present and future vulnerability to ground future
  adaptation policy development in present-day experience.
• Consider current development policies and proposed future
  activities and investments, especially those that may increase
  vulnerability.


                                               Atmospheric Research
      Foresighting your project

• Visualise how you will present the results
  (graph, text, table, animation)
• Rehearse how you will communicate the
  uncertainties
• Anticipate questions upon presentation or
  review
• How will you engage different stakeholders?




                                      Atmospheric Research

				
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