Transcript Towards Local Costing of Climate Change Impacts for Decision

Towards Local Costing of Climate Change
Impacts for Decision Making in Adaptation
Alistair Hunt and Tim Taylor, University of Bath, UK
Session 32 - Economic Costs of Adapting and not
Adapting to Climate Change
International Scientific Congress on Climate Change,
Copenhagen, March 11, 2009.
Research: Overview
• Objective: provide quantitative estimates of
economic welfare costs of CC impacts
projected to face stakeholders at local scale,
within UK.
 benefits gained from taking adaptive
action.
• test robustness of methodological components:
stakeholder-driven; scenario down-scaling; use
of non-market values
Impacts and primary stakeholder
Impact considered
Primary Stakeholder
Road maintenance in summer
Cambridgeshire County Council
(subsidence) and winter (salting - ice)
Domestic property subsidence
Association of British Insurers
Historic garden maintenance in
Cornwall (lawn mowing and pest
control)
National Trust
Health impacts of hot summers in
Hampshire
Hampshire County Council
Methods
• Stakeholder role: scoping; data provision; method
validation
• Quantify current vulnerability – analogue data; mix
of means and extremes
• Impact projections to 2100
– 4 Down-scaled climate scenarios
• (correspond to: A1F1, A2, B2 & B1 IPCC SRES)
– Socio-economic scenarios
• evolution of ‘stock-at-risk’; ‘prices’, and; adaptive
capacity
Climate Change Impact and Adaptation
Costs: A Simplified framework
Results
• Impact costs in annual terms - three 30-year time periods; for
4 climate scenarios
– climate change gross & net of socio-economic change,
discounted using exponentially declining rates, and
undiscounted.
– Stakeholders identified adaptation options
• initial assessment of adaptation cost and its distribution
of burden e.g. between private and public sector
economic agents.
Annual Impact multipliers over baseline
(2011–2040 time period, undiscounted)
Impact considered
Primary Stakeholder
Road maintenance in summer
(subsidence) and;
winter (salting - ice)
13 – 15
Domestic property subsidence
12 - 15
Historic garden maintenance in
Cornwall (lawn mowing and pest
control)
1.2 – 1.5
Health impacts of hot summers in
Hampshire
16 - 18
(-) 1.3 – 1.6
Example: Cost of Building Subsidence in UK
350
300
Annual
250
Subsidence 200
cost in UK 150
(£m )
100
50
0
2020s
2050s
2080s
L no L M-L M-L M-H M-H H no H
CC CC no CC no CC CC CC
CC
CC
Em issions Scenario
Aggregate Benefits & Costs - adaptation options
to domestic property subsidence
Adaptation
Measure
Benefit
Cost
Higher insurance
premiums to cover
higher remediation
costs
Withdrawal of
insurance cover for
properties vulnerable to
subsidence
Insurer covers costs of
increased number of
claims
£3.6 – £12.1bn1
Increased household
insurance costs.
Insurer avoids
increased exposure.
£3.6 – £12.1bn.
Loss of property
values and if remain
inhabited will bear
full cost
Underpinning &
structural measures
£3.6 – £12.1bn.
Max avoided loss.
£28 - £69bn2.
Total cost of measures
for all properties at
risk
£1.5 – £5.6bn3
£2.0 – £3.5bn4
Not known
Not known
Building regulations
for:
- deeper
foundations of
1 metre
- building
materials
Bearer of
Cost Burden
Household bears
increased costs
Householders bear
full remediation costs.
Possible ghettoisation for low income
groups
Benefit borne by
insurer
&
house
owner
Cost borne by housebuilder or owner
Benefit borne by
insurer
&
house
owner
Cost borne by housebuilder or owner
Aggregate Benefits & Costs - adaptation options
to domestic property subsidence
Adaptation
Measure
Spatial
policy
Benefit
planning £1.5 – £5.6bn5
Clearance of nearby
vegetation
or
restrictions on future
planting
Regular
water
sprinkling
of
vegetation
Max avoided loss.
£3.6 – £12.1bn.
Max avoided loss
£3.6 – £12.1bn.
Max avoided loss
Cost
Bearer of
Cost Burden
Benefit borne by
Loss of land values
insurer & house
and possible social
owner.
costs of higher density
Cost borne by house
housing
and land owners.
Not known6
Cost borne by house
and land owners
Not known
Cost borne by house
and land owners
Conclusions
• Primary stakeholders able to use generated
quantitative information in planning processes.
Common money metric found to be valuable
– At least as important for planning for current vulnerability
as for future vulnerability under CC
• Uncertainty in results provokes different responses
according to stakeholder contexts, preferences.
– Spread risk across stakeholders e.g. Promote range of
responses (property subsidence)
– Reactive e.g. Wait for trend to become clear (Gardens)
– Proactive e.g. Bid for more financial resources to centre
(Health, roads)
Conclusions II
• Down-scaling to sub-national level increases
confidence with which stakeholders approach
exercise
•  tension with introduced scaling uncertainties
• Research priority: need to understand economic, and
other, factors that determine adaptation response
e.g. what is value of information likely to be for
different actors?