Impact of Climate Change on the Historic environment of Wales.

1. CLIMATE
CHANGE AND
THE HISTORIC
ENVIRONMENT
PRESENTATION
TO HEG
MAY 2012

2. For this study we are
examining:
The direct impact of
climate change
But the greatest impact on
the historic environment
may be caused by:
• The impact of some adaptive
responses to climate change
• The impact of mitigation to
reduce the threat of climate
change
• The impact of opportunities
offered by climate change

3. Predicting climate change
• UKCIP Climate change scenarios summarising likely
outcomes for mid-range emissions: 2020, 2050 and 2080
for Wales
• High level of uncertainty over projections
Predicted changes – 2050s medium emissions scenario
Season Temperature: Temperature: Rainfall Outcome
seasonal mean mean daily max descriptor
and (min )
Summer 2.5oC 3.4oC (2.6oC) -17% Hotter, drier
summers
Winter 2oC +14% Warmer wetter
winters
Annual 0% More frequent
extreme events

4. Descriptors and outcomes
of predicted climate change
Descriptor Outcome Outcome Outcome
Warmer wetter More frequent Migration of pests More frequent high
winters rainfall; flooding and diseases winds/storms
events
Warmer mean Rise in sea levels Longer growing Migration of pests
temperatures season and diseases into
Britain
Hotter drier Drying out,
summers desiccation and Stress on some Drying and shrinking
erosion of trees and plants of clay soils
wetlands
More frequent Frequent high
extreme weather winds/storms

5. Description of Warmer mean temperatures Hotter, drier summers Warmer, More frequent
change wetter extreme
winters weather
Migration of Drying out,
Longer Stress on Drying and More
Rise in sea pests and desiccation Frequent high
Outcome of change growing some trees shrinking of flooding
levels diseases and erosion winds/storms
season and plants clay soils events
into Britain of wetlands
Historic
Environment Asset
Historic parks and
gardens
Registered historic
landscapes The
Archaeological sites in
an upland
environment
impact of
Archaeological sites
on upland
peat/blanket bog
climate
Archaeological sites
on farmland change
Archaeological sites in
forestry/woodland on
historic
Archaeological sites
on wetland/wetland
margins
Historic buildings
assets
Archaeological sites
on sand dunes
Historic buildings and
archaeological sites
below the 1.0 m
contour
Archaeological sites
on the foreshore
Historic buildings and
archaeological sites on
floodplains and in
valley bottoms
Historic buildings and
archaeological sites in
a coastal location but
not likely to be
flooded

6. Assessing risks to historic assets
Scale Point Description
The extent of
impact on 1 Limited
historic 2 Moderately Limited
environment 3 Moderate
assets 4 Moderately extensive
5 Extensive
Scale Point Description
-3 Large negative impact
The severity
-2 Moderate negative impact
of impact on
-1 Small negative impact
historic
0 Neutral
environment
+1 Small beneficial impact
assets
+2 Moderate beneficial impact
+3 Large beneficial impact

7. Assessing risks to historic assets
Scale Point Description
0 Not vulnerable to change The
1 Slightly vulnerable to change vulnerability of
2 Slight/moderately vulnerable to historic
change environmental
3 Moderately vulnerable to change assets to
4 Moderate/Highly vulnerable to change change
5 Highly vulnerable to change
Impact Significance = Extent x Severity x vulnerability

8. Description of change
More frequent extreme weather events
Outcome of change
Frequent high winds/storms
Location
All historic parks and gardens
Impact on historic environment assets
A. Mature trees
B. Historic buildings and structures
Extent Severity Vulnerability Significance of Impact
Example:
A 2 -3 3 -18 moderate negative
Risk
B 2 -1 2 -4 small negative
assessment
Risk assessment of historic assets
A. More frequent storms and extreme weather events will have a disproportionate impact on mature and
matrix
veteran trees, as these by their nature tend to be the largest, tallest examples in parks and gardens. As
some species take several hundred years to reach maturity, the impact of more frequent storms will
have a short, medium and long-term impact.
B. Many historic parks and gardens contain buildings and other structures which are likely to be
damaged by more frequent storms.
Specific gaps in knowledge
Responses to outcome of change
Replacement planting damaged trees of species more resistant to storm damage.
Notes and references

9. Example: Historic parks & gardens
– frequent high winds/storms
Change: more frequent extreme
weather events
Location: all historic parks and gardens
Assets: A – mature trees
B – buildings/structures
Extent Severity Vulnerability Significance
A 2 -3 3 -18 moderate
negative
B 2 -1 2 -4 small negative
• Risk Assessment
• Gaps in knowledge
• Response to outcomes

10. Example: Historic parks &
gardens – longer growing season
Change: warmer mean temperatures
Outcome: longer growing season
Location: all historic parks and gardens
Assets: A – character of parks/gardens
Extent Severity Vulnerability Significance
A 5 2 3 15 moderate
positive
• Risk Assessment
• Gaps in knowledge
• Response to outcomes

11. Example: Historic parks & gardens
– hotter drier summers
Change: hotter drier summers
Outcome: stress on trees, shrubs, plants
Location: all historic parks and gardens
Assets: A – trees, shrubs, plants in historic
parks/gardens
Extent Severity Vulnerability Significance
A 2 0 4 0 – neutral impact
• Risk Assessment
• Gaps in knowledge
• Response to outcomes

12. Example: Historic parks & gardens
– migration of pests and diseases
Change: Warmer mean temperature
Outcome: migration of pests/diseases
Location: all historic parks and gardens
Assets: A – trees, shrubs, plants in historic
parks/gardens
Extent Severity Vulnerability Significance
A 5 -1 43 -15 Moderate
negative
• Risk Assessment
• Gaps in knowledge
• Response to outcomes

13. Historic parks and gardens –
summary
Location Historic parks and gardens
Description of Outcome of Location Impact on historic Significance of
change change environment impact
assets
Warmer mean Longer growing All historic parks The character of Moderate positive
temperatures season and gardens historic parks and
gardens
Migration of pests All historic parks Trees, shrubs and Moderate negative
and diseases into and gardens plants in historic
Britain parks and gardens
Hotter drier Stress on trees and All historic parks Trees, shrubs and Moderate negative
summers plants and gardens plants in historic
parks and gardens
More frequent Frequent high All historic parks Mature trees Moderate negative
extreme weather winds/storms and gardens Historic buildings Small negative
events and structures

14. Example: Historic buildings &
archaeological sites on floodplains
Change: warmer wetter winters
Outcome: more flooding events
Location: all historic buildings and archaeological sites
on floodplains and in valley bottoms
Assets: A – damage to buildings and fittings
B – damage to fabric of towns/villages
C – damage to archaeological sites
Extent Severity Vulnerability Significance
A 5 -3 5 -75 High negative
B 3 -2 -3 -18 Moderate negative
C 5 -1 -1 -5 Small negative

15. More flooding events
A RCAHMW study identified 5412
listed buildings on floodplains, 302
scheduled ancient monuments and
12,000 other archaeological sites

16. Historic landscapes
- Cumulatively a highly significant impact
Location
Description of change Outcome of change Impact on historic Significance of impact
environment assets
Warmer mean Rise in sea levels Waterside landscapes Moderate negative
temperatures such as coastland,
estuaries and river valleys
Longer growing season Farmland and upland Moderate negative
areas
Migration of pests and Areas of woodland and Moderate negative
diseases into Britain forestry
Hotter drier summers Drying out, desiccation Wetland habitats, such as Moderate negative
and erosion of wetlands blanket bog, and upland
areas.
Stress on some trees and Native woodland Moderate negative
plants
Warmer, wetter winters More flooding events Historic towns and cities Moderate negative
and areas of woodland.
More frequent extreme Frequent high winds and Historic buildings, areas Small - moderate
weather storms of woodland and forestry negative
and archaeological
monuments

17. Description of Warmer mean temperatures Hotter, drier summers Warmer, More frequent
change wetter extreme
winters weather
Migration of Drying out,
Longer Stress on Drying and More
Rise in sea pests and desiccation Frequent high
Outcome of change growing some trees shrinking of flooding
levels diseases and erosion winds/storms
season and plants clay soils events
into Britain of wetlands
Historic
Environment Asset
Historic parks and
gardens
Registered historic
Summary of
landscapes
Archaeological sites in
impact
an upland
environment
Archaeological sites
significance
on upland
peat/blanket bog
Archaeological sites
on farmland
Archaeological sites in
forestry/woodland
Archaeological sites
on wetland/wetland
margins
Historic buildings
Archaeological sites
on sand dunes
Historic buildings and
archaeological sites Impact
below the 1.0 m
contour significance:
Archaeological sites
on the foreshore
Red – high
Historic buildings and
archaeological sites on
Orange –
floodplains and in
valley bottoms
moderate
Historic buildings and
archaeological sites in Green – low
a coastal location but
not likely to be Blue – positive
flooded

18. Adaptation, Mitigation and
Opportunities
Impact of some adaptive responses to climate change
Coastal defences
Flood defences
Flood water disposal/infiltration
Expansion of forestry/woodland
Impact of mitigation to reduce threats of climate change
Windfarms
Solar panels
Micro hydro-electric schemes
Building insulation
Impact of opportunities offered by climate change
New types of crops
Expansion of arable farming
Expansion of farmland onto marginal land

19. Next Steps
•Risk based prioritisation
of historical assets
•Risk mapping
•Exploration of adaptive
strategies
•Strategic planning and
programming
•‘Asset proofing’ of
sectoral policies
mitigating climate change