climate change & the historic environment - may 2012 john powell

CLIMATE CHANGE AND THE HISTORIC ENVIRONMENT

PRESENTATION TO HEG

MAY 2012

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

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

Season Temperature:

seasonal mean

Temperature:

mean daily max

and (min )

Rainfall Outcome

descriptor

Summer 2.5oC 3.4oC (2.6oC) -17% Hotter, drier

summers

Winter 2oC +14% Warmer wetter

winters

Annual 0% More frequent

extreme events

Predicted changes – 2050s medium emissions scenario

Descriptors and outcomes

of predicted climate change

Descriptor Outcome Outcome Outcome

Warmer wetter

winters

More frequent

rainfall; flooding

events

Migration of pests

and diseases

More frequent high

winds/storms

Warmer mean

temperatures

Rise in sea levels Longer growing

season

Migration of pests

and diseases into

Britain

Hotter drier

summers

Drying out,

desiccation and

erosion of

wetlands

Stress on some

trees and plants

Drying and shrinking

of clay soils

More frequent

extreme weather

Frequent high

winds/storms

Description of

change

Warmer mean temperatures Hotter, drier summers Warmer,

wetter

winters

More frequent

extreme

weather

Outcome of change Rise in sea

levels

Longer

growing

season

Migration of

pests and

diseases

into Britain

Drying out,

desiccation

and erosion

of wetlands

Stress on

some trees

and plants

Drying and

shrinking of

clay soils

More

flooding

events

Frequent high

winds/storms

Historic

Environment Asset

Historic parks and

gardens

Registered historic

landscapes

Archaeological sites in

an upland

environment

Archaeological sites

on upland peat/blanket bog


on farmland


forestry/woodland


on wetland/wetland

margins

Historic buildings


on sand dunes

Historic buildings and

archaeological sites

below the 1.0 m

contour


on the foreshore

Historic buildings and archaeological sites on

floodplains and in

valley bottoms


archaeological sites in

a coastal location but

not likely to be

flooded

The impact of climate change on historic assets

The extent of

impact on

historic

environment

assets

The severity

of impact on

historic

environment

assets

Assessing risks to historic assets

Scale Point Description

1 Limited

2 Moderately Limited

3 Moderate

4 Moderately extensive

5 Extensive


-3 Large negative impact

-2 Moderate negative impact

-1 Small negative impact

0 Neutral

+1 Small beneficial impact

+2 Moderate beneficial impact

+3 Large beneficial impact

The

vulnerability of

historic

environmental

assets to

change


0 Not vulnerable to change

1 Slightly vulnerable to change

2 Slight/moderately vulnerable to

change

3 Moderately vulnerable to change

4 Moderate/Highly vulnerable to change

5 Highly vulnerable to change

Assessing risks to historic assets

Impact Significance = Extent x Severity x vulnerability

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

A 2 -3 3 -18 moderate negative

B 2 -1 2 -4 small negative

Risk assessment of historic assets

A. More frequent storms and extreme weather events will have a disproportionate impact on mature and 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

Example:

Risk

assessment

matrix

Example: Historic parks & gardens

– frequent high winds/storms

Extent Severity Vulnerability Significance

A 2 -3 3 -18 moderate

negative

B 2 -1 2 -4 small negative

Change: more frequent extreme

weather events

Location: all historic parks and gardens

Assets: A – mature trees

B – buildings/structures

• Risk Assessment

• Gaps in knowledge

• Response to outcomes

Example: Historic parks &

gardens – longer growing season


A 5 2 3 15 moderate

positive

Change: warmer mean temperatures

Outcome: longer growing season


Assets: A – character of parks/gardens

• Risk Assessment




– hotter drier summers

• Risk Assessment




A 2 0 4 0 – neutral impact

Change: hotter drier summers

Outcome: stress on trees, shrubs, plants


Assets: A – trees, shrubs, plants in historic

parks/gardens


– migration of pests and diseases

Change: Warmer mean temperature

Outcome: migration of pests/diseases


Assets: A – trees, shrubs, plants in historic

parks/gardens


A 5 -1 43 -15 Moderate

negative

• Risk Assessment



Historic parks and gardens –

summary

Location Historic parks and gardens

Description of

change

Outcome of

change

Location Impact on historic

environment

assets

Significance of

impact

Warmer mean

temperatures

Longer growing

season

All historic parks

and gardens

The character of

historic parks and

gardens

Moderate positive

Migration of pests

and diseases into

Britain

All historic parks

and gardens

Trees, shrubs and

plants in historic

parks and gardens

Moderate negative

Hotter drier

summers

Stress on trees and

plants

All historic parks

and gardens

Trees, shrubs and

plants in historic

parks and gardens

Moderate negative

More frequent

extreme weather

events

Frequent high

winds/storms

All historic parks

and gardens

Mature trees Moderate negative

Historic buildings

and structures

Small negative

Example: Historic buildings &

archaeological sites on floodplains


A 5 -3 5 -75 High negative

B 3 -2 -3 -18 Moderate negative

C 5 -1 -1 -5 Small negative

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

More flooding events

A RCAHMW study identified 5412listed buildings on floodplains, 302scheduled ancient monuments and12,000 other archaeological sites

- Cumulatively a highly significant impact Historic landscapes

Location

Description of change Outcome of change Impact on historic

environment assets

Significance of impact

Warmer mean

temperatures

Rise in sea levels Waterside landscapes

such as coastland,

estuaries and river valleys

Moderate negative

Longer growing season Farmland and upland

areas

Moderate negative

Migration of pests and

diseases into Britain

Areas of woodland and

forestry

Moderate negative

Hotter drier summers Drying out, desiccation

and erosion of wetlands

Wetland habitats, such as

blanket bog, and upland

areas.

Moderate negative

Stress on some trees and

plants

Native woodland Moderate negative

Warmer, wetter winters More flooding events Historic towns and cities

and areas of woodland.

Moderate negative

More frequent extreme

weather

Frequent high winds and

storms

Historic buildings, areas

of woodland and forestry

and archaeological

monuments

Small - moderate

negative

Impact

significance:

Red – high

Orange –

moderate

Green – low

Blue – positive

Description of

change

Warmer mean temperatures Hotter, drier summers Warmer,

wetter

winters

More frequent

extreme

weather

Outcome of change Rise in sea

levels

Longer

growing

season

Migration of

pests and

diseases

into Britain

Drying out,

desiccation

and erosion

of wetlands

Stress on

some trees

and plants

Drying and

shrinking of

clay soils

More

flooding

events

Frequent high

winds/storms

Historic

Environment Asset

Historic parks and

gardens

Registered historic

landscapes


an upland

environment


on upland peat/blanket bog


on farmland


forestry/woodland


on wetland/wetland

margins

Historic buildings


on sand dunes


archaeological sites

below the 1.0 m

contour


on the foreshore

Historic buildings and archaeological sites on

floodplains and in

valley bottoms


archaeological sites in

a coastal location but

not likely to be

flooded

Summary of

impact

significance

Impact of some adaptive responses to climate changeCoastal defences

Flood defences

Flood water disposal/infiltration

Expansion of forestry/woodland

Impact of mitigation to reduce threats of climate changeWindfarms

Solar panels

Micro hydro-electric schemes

Building insulation

Impact of opportunities offered by climate changeNew types of crops

Expansion of arable farming

Expansion of farmland onto marginal land

Adaptation, Mitigation and

Opportunities

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

climate change & the historic environment - may 2012 john powell

Documents