Atmospheric Research Coping with Climate Risk climate sensitivity, coping ranges and risk Roger N. Jones AIACC Training Workshop on Adaptation and Vulnerability

Atmospheric Research

Coping with Climate Riskclimate sensitivity, coping ranges and risk

Roger N. Jones

AIACC Training Workshop on Adaptation and Vulnerability

TWAS, Trieste

June 3-14 2002


Coverage

• Impacts are sensitive to climate variability and extremes

• Coping ranges as a tool to understand the relationship between V, I and A.

• Operationalising coping ranges for risk assessment


Impacts are sensitive to climate variability and extremes

Sensitivity to climate is:

how much a system or activity is affected by climate-related stimuli


Insensitive Unaffected by rain, hail, sun, wind or snow


Sensitive Easily affected by rain, hail, sun, wind and snow


Sensitivity to what?

Sector Sensitivity to what?

Water Rainfall variability, flood, drought

Agriculture ENSO, flood, drought, cool/hotextremes, storms

Health Hot/wet conditions, temperatureextremes, violent storms, floods, cropand water shortages

Coasts Storm surges, wind/wave climates,pressure extremes, tidal extremes

Biodiversity Fire, flood, drought, storms


Extreme temperature

20

25

30

35

40

45

0 25 50 75 100

Days

Max

imu

m T

emp

erat

ure

(°C

)


0

5

10

15

20

25

30

35

0 25 50 75 100

Days

Hea

t S

tres

s (D

egre

e D

ays

>35

°C)

Extreme temperature

Incr

easi

ng

str

ess


How do we assess extremes?

In two ways, rarity and impact:

1. As a rare event

2. As an event with extreme outcomes

Extreme events are rare events with significant impacts, but under climate change may become more common


Types of extreme climate events

Type Description Variable Measure

Simpleevents

Exceeding criticallevel on a continuousscale

Extreme rainfallTemperature

FrequencyReturn periodSequenceDuration

Complexevents

Weather eventscombining multiplevariables and/orresulting in multipleimpacts

Tropical cyclonesENSO eventsDrought

Frequency magnitudeSeverity ofimpacts

Singularevents

A possible futureclimatic state withpotentially extremeoutcomes

Cessation of deep-ocean circulationIce sheet collapse

Probability magnitude ofimpact


Confidence levels

Climate VariableAtmospheric CO2 concentrationGlobal-mean sea-levelGlobal-mean temperatureRegional seasonal temperatureRegional temperature extremesRegional seasonal precipitation/cloud

cover

Changes in climatic variability (e.g. El Niño, daily precipitation regimes)

Rapid or non-linear change (e.g. disintegration of the West Antarctic Ice Sheet)

High confidence

Low confidence

Very low or unknown


Modelling climate variability

Most impacts are sensitive to climate variability rather than the mean (atmospheric CO2 is a notable exception)

Climate models represent climate variability relatively poorly

Realistic and plausible scenarios of climate variability are needed


Linking climate to impacts

Climate system

Impacted activity

Socio-economicsystem

Current climate

Current adaptations

Future climate

Future adaptations


IPCC 1994

3 TEST METHOD/SENSITIVITY

4 SELECT SCENARIOS

5 ASSESS BIOPHYSICAL IMPACTSASSESS SOCIOECONOMIC IMPACTS

6 ASSESS AUTONOMOUS ADJUSTMENTS

7 EVALUATE ADAPTATION STRATEGIES

1 DEFINE PROBLEM

2 SELECT METHOD


Two approaches to V&A

V = I – A

V = I – A, t

t = 0, current climate, reference or baseline

Time t relates to the planning horizon


Coping with climate (variability and extremes)

A system can cope with some combinations of climate but other combinations will cause damage

The ability to cope is a function of the sensitivity of a system to climate and its response to that sensitivity

This response is the interaction of socio-economic and biophysical factors


Coping range under current climate

Stationary Climate & Coping Range

CopingRange

Vulnerable

Vulnerable


Coping range under current climate - limited ability to cope


CopingRange

Vulnerable

Vulnerable


Coping range structure (1)

A coping range exists where climate – socioeconomic interactions are beneficial or suffer only tolerable damage. The width of the coping range is in part due to historical adaptation

It is separated from an area of vulnerability by a threshold. The threshold can be critical, marking a level of harm that is intolerable, or mark a given level of hazard

Beyond the coping range and threshold is a zone of vulnerability


Coping range structure (2)

SimpleExpressed in terms of one or two climate

variables (e.g. rainfall, temperature)

ComplexExpressed in terms of secondary or tertiary

variables with a known relationship with climate (e.g. stream flow, crop yield, rates of infectious disease)


Coping range dynamics

Two aspects of the coping range can change:

1. Climate

2. Socioeconomic (affecting the width of the coping range)a. autonomous socioeconomic change may increase or

decrease the width

b. climatic events may trigger a contraction (through damage) or an expansion (adaptation to similar future events)

We would like to addc. expansion to reduce anticipated future vulnerability


Changing coping range - socioeconomic change

Stationary Climate

CopingRange

Vulnerable

Vulnerable

Coping Range reducing

CopingRange

Vulnerable

VulnerableStationary Climate Coping Range increasing


Changing coping range - response to climate stress

CopingRange

Vulnerable

VulnerableStationary Climate

Coping Range reducing due to climate shocks

CopingRange

Vulnerable

VulnerableStationary Climate Coping Range increasing due to climate shocks


Future climate - no adaptation

CopingRange

Vulnerable

Vulnerable


Changing Climate


Future climate with adaptation

Policy Horizon

Planning Horizon

CopingRange

Vulnerable

Vulnerable

Adaptation

Changing Climate Stationary Climate & Coping Range


Thresholds

A non-linear change in a measure or system, signalling a physical or behavioural change

Climate-related thresholds are used to mark a level of hazard


Thresholds as climate hazards

There are two ways to construct climate hazards to use as thresholds

1. Natural hazards approach – a fixed threshold such as 1 in 100-year flood, storm surge or given storm strength applied over time and space. Especially good for locating most vulnerable areas.

2. Vulnerability-based approach – the climatic conditions resulting in a degree of harm that exceed the limits of tolerance. Usually specific to a given activity and location (e.g. drought, water supply, crop yields). Useful when constructed with stakeholder participation.


Thresholds

Biophysical(simple to complex)

• Tropical cyclone

• Coral bleaching

• ENSO event

• Island formation

• Island removal

Socioeconomic(usually complex)

• Legal/regulatory

• Profit/loss

• Cultural

• Agricultural

• Critical


Critical thresholds

A level considered to represent an unacceptable degree of harm

This is a value judgement and may be decided by stakeholders, be a legal requirement, a safety requirement, a management threshold etc


Planning horizons

2000

2020

2040

2060

2080

2100

New irrigation projects

Large dams

Bridge design life

Agriculture (whole farm planning)

Tree crops

Airport design life

Plant breeding (new crops)

Forest lease agreements

Pulp plantations

Major urban infrastructure

Coastal/tourism infrastructure

Election cycles/profit & loss

Generational succession

Long-term biodiversity

National parks

Intergenerational equity


Using coping ranges to assess risk– current risk

• Choose a reference or baseline period pertinent to both climate and the socioeconomic background

• Calculate threshold exceedance based on climate exposure during the reference period

• Existing adaptations and those needed to reduce risk under present climate provide the short-term options for a ‘win-win’ adaptation strategy (helping cost-benefit and efficiency criteria)


Using coping ranges to assess risk– future risk

• Each scenario will give a different probability of threshold exceedance

• If using single, or several scenarios, these should be related to the full range of uncertainty for climate change, when communicating results

• The effect of climate and socioeconomic scenarios can be assessed separately or together

• Methods can range from semi-quantitative (simple) through to the application of advanced probabilistic techniques (difficult but interesting)


What is a risk?

Two uses

1. In general language

2. A specific operational meaning


Characterising risk

Risk is a combination of hazard, likelihood and vulnerability, i.e. stress, how likely that stress is, and how much damage that stress will cause.


Natural hazards approach to risk

Fixed climate hazard - e.g. 1/100 flood, hurricane.

Likelihood - frequency of occurrence; likelihood that it will occur

Vulnerability - damage incurred

Risk = f(hazard*likelihood, vulnerability)


Natural hazards approach to risk

ExamplesHeat stress - hastened mortality per 103 or 105 populationFlood damage mapping (e.g. $$ damage or dwellings

inundated per 100 year flood)Storm damage mapping (structural damage for a given

windspeed in $$ or no. of buildings damaged)Disease mapping (vector density aligned with infection

rates)ENSO frequency and intensity aligned with known

hazards


Vulnerability-based approach to risk

Level of climate associated with given level of harm, e.g. critical threshold

Likelihood - frequency of occurrence; likelihood that it will occur

Risk = f(hazard*vulnerability, likelihood)


Example - water supply for irrigation and wetland management

Macquarie catchment - AustraliaClimate baseline: Daily P and Ep data 1890-1996 infilled across the

catchment

Management reference: 1996 infrastructure and catchment management rules

Irrigation water allocation is capped and supply is shared between irrigation and environmental flows through the Macquarie Marshes

Thresholds

Supply of 350 GL into the Macquarie Marshes for waterbird breeding

Irrigation water allocation of 0%, 50% or 100%


Simulated flow into the Macquarie Marshes - baseline case

0.E+00

5.E+05

1.E+06

2.E+06

2.E+06

1890 1910 1930 1950 1970 1990

Year

Tot

al A

nnua

l Flo

w

Bird breeding threshold


Simulated flow into the Macquarie Marshes -10% flow (IS92c HCM3)

0.E+00

5.E+05

1.E+06

2.E+06

2.E+06

1890 1910 1930 1950 1970 1990

Year

Tot

al A

nnua

l Flo

w

Critical period Bird

breeding threshold


Simulated flow into the Macquarie Marshes -10% flow (IS92c HCM3)

1.E+04

1.E+05

1.E+06

1.E+07

020406080100

Percent

Tot

al A

nnua

l Flo

w

44%52%

Bird breeding threshold


Simulated irrigation allocations baseline and -10% flow (IS92c

HCM3)

0

20

40

60

80

100

1890 1910 1930 1950 1970 1990

Year

Flo

w (

Gl x

10)

Allocations Alloc - 10%


Simulated irrigation allocations baseline and -10% flow (IS92c

HCM3)

0

20

40

60

80

100

020406080100

Percent

Ann

ual I

rrig

atio

n A

lloca

tion

(%)

51%56% 31% 22%

1%6%


Sensitivity analysis for Burrendong Dam storage

Exceeding critical threshold

0

10

20

-10-20-30-40

0 5-5-5

0

5

10

10

15

-10

Rainfall change (%)

Po

ten

tial

eva

po

rati

on

ch

ang

e (%

)

IS92c HCM3


Sensitivity analysis for Burrendong Dam storage

0

10

20

-10-20-30-40

0 5-5-5

0

5

10

10

15

-10

Rainfall change (%)

Po

ten

tial

eva

po

rati

on

ch

ang

e (%

)

Exceeding critical threshold

Wettest (SRES)

Driest (SRES)


Changes to MAF for 9 models in 2030 (%)Based on IPCC 2001

B1 at 1.7°C0.55°C

A1 at 2.5°C0.91°C

A1T at 4.2°C1.27°C

Low

-16

-8

0

Mid

-24

-16

-8

0

High

-30

-20

-10

0


Changes to Burrendong Dam storage 2030

<60

<70

<80

<90

<95

<100

<50

Cumulative Probability (%)

0

10

20

-10-20-30-40

0 5-5-5

0

5

10

10

15

-10

Rainfall change (%)

Po

ten

tial

eva

po

rati

on

ch

an

ge

(%)


Probabilities of flow changes - impacts view

Range of possible outcomes

0

10

20

30

40

50

60

70

80

90

100

-40-30-20-1001020

Change in supply (%)

Cu

mu

lativ

e P

rob

ab

ility

Burrendong Marshes Irrigation

Likeliest outcome


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.

Documents

Atmospheric Research Coping with Climate Risk climate sensitivity, coping ranges and risk Roger N. Jones AIACC Training Workshop on Adaptation and Vulnerability