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S e t t i n g
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Climate
E n v i r o n m e n t
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A u d i t
10
Climate
Introduction
10.1
Despite the march of technological progress, weather and climate still have major impacts on
people and communities. Even in the relatively temperate conditions which prevail in
Edinburgh, health, welfare and livelihoods are directly affected by weather. Natural habitats and
wildlife are also very much influenced by even modest variations in temperature, sunlight,
precipitation, wind and other climatic factors, and in turn these have direct relevance for human
activity.
10.2
In this context, it will be important to examine any indications of climate change in Edinburgh,
and understand what the repercussions might be. At a global scale there is now irrefutable
evidence not only that the earth is warming, but that human activity is the driving force behind
this – a feature which distinguishes the current trend from previous warming episodes. Global
warming is now widely regarded as the biggest single threat facing mankind, and Edinburgh must
play its part in the national and international effort to restore an equilibrium.
General climatic characteristics
10.3
Edinburgh is fortunate to enjoy a relatively benign, equable climate, with few extremes of
temperature or precipitation. It is subject mainly to maritime rather than continental influences,
leading to cooler and more variable conditions than those typical in the south east of Britain.
However, this is moderated by its east coast location and its distance from the more mountainous
areas of Scotland. Rainfall and temperature are both lower and sunshine more plentiful
compared with areas further to the west which are exposed to the dominant moist south westerly
air flow from the Atlantic. Proximity to the sea tends to modulate the daily temperature range,
with daytime temperatures not rising so high and night-time temperatures not dropping so low as
places further inland.
10.4
Storms and lightning are relatively infrequent, and snow rarely lies for long, compared with some
other parts of the UK. However, in common with other parts of the east coast, the ‘haar’ is a
distinctive feature of Edinburgh’s climate. This is usually associated with anticyclonic
conditions, when low cloud and mist form over the cool waters of the North Sea and drift inland.
The dull, overcast conditions sometimes only affect the coastal strip, and often clear up as the day
progresses.
10.5
Table 1 sets out some comparisons between climatic conditions in Edinburgh and five other
selected locations across Great Britain (Edinburgh, Glasgow, Aberdeen and Manchester airports,
Cardiff, and Greenwich in London). The figures are all averages for the period 1971 to 2000,
thirty years being the standard period used by the Meteorological Office to produce climate data.
10.6
The figures show that average temperatures in Edinburgh are lower than the other five cities,
apart from Aberdeen. The mean daily maximum temperature for the whole year is 2.60C cooler
than London and 2.10C cooler than Cardiff. (The mean daily maximum is the average of the
highest temperature reached each day). The mean daily minimum is also more than 20C cooler
than the southern cities. The temperature difference is greater in the summer than in the winter,
with London being nearly 4 degrees warmer than Edinburgh in July and August, at the peak of
the Festival period. In common with all the other comparator cities, July is the hottest month in
Edinburgh while January is the coldest. Daytime temperatures can be expected to rise to 190C in
July, compared with just 60C in January.
10.7
Edinburgh has a marginally higher incidence of air frosts than Aberdeen (54.5 days per year
recording a frost). Edinburgh and Aberdeen both record significantly more air frosts than
Glasgow, Manchester, Cardiff and London. Both cities on the east coast of Scotland can
normally expect at least one day of air frost in May, whereas this is a rarity elsewhere.
Compared with Aberdeen, Edinburgh is more prone to frosts in the late autumn (October to
December), but less prone in the winter and early spring (January to April).
Table 1 : Climatic comparisons : Edinburgh and selected other cities (1971 – 2000 data)
(a) Mean maximum daily temperature (0C)
January
February
March
April
May
June
July
August
September
October
November
December
Year
Edinburgh
airport
Glasgow
airport
Aberdeen
airport
Manchester
airport
Cardiff
Greenwich
(London)
6.4
6.8
8.8
10.9
14.2
17.0
19.0
18.7
16.0
12.6
9.0
7.0
12.2
6.4
7.0
9.1
12.1
15.6
17.8
19.6
19.1
16.1
12.6
9.0
7.0
12.6
5.7
6.1
8.0
9.9
12.7
15.3
17.6
17.5
14.9
11.8
8.2
6.4
11.2
6.9
7.3
9.5
11.9
15.7
18.0
20.3
20.1
17.1
13.5
9.6
7.6
13.2
7.9
8.2
10.6
13.1
16.7
19.2
21.5
21.3
18.4
14.6
10.9
8.9
14.3
7.9
8.2
10.9
13.3
17.2
20.2
22.8
22.6
19.3
15.2
10.9
8.8
14.8
(b) Mean minimum daily temperature (0C)
January
February
March
April
May
June
July
August
September
October
November
December
Year
Edinburgh
airport
Glasgow
airport
Aberdeen
airport
Manchester
airport
Cardiff
Greenwich
(London)
0.7
0.9
2.1
3.4
5.8
8.6
10.5
10.4
8.5
5.9
2.7
1.3
5.1
1.6
1.7
2.9
4.4
7.0
9.7
11.8
11.5
9.4
6.7
3.6
2.2
6.1
0.4
0.6
1.5
2.7
5.0
7.8
9.9
9.8
8.0
5.6
2.6
1.1
4.6
1.5
1.6
3.1
4.5
7.4
10.1
12.3
12.1
10.0
7.2
3.9
2.3
6.4
2.1
2.1
3.7
4.8
7.8
10.5
12.8
12.5
10.0
7.5
4.3
3.2
6.8
2.4
2.2
3.8
5.2
8.0
11.1
13.6
13.3
10.9
8.0
4.8
3.3
7.2
(c) Days of air frost
January
February
March
April
May
June
July
August
September
October
November
December
Year
Edinburgh
airport
Glasgow
airport
Aberdeen
airport
Manchester
airport
Cardiff
Greenwich
(London)
11.7
10.1
7.2
4.1
0.9
0.0
0.0
0.0
0.3
2.0
7.6
10.5
54.5
8.8
7.5
4.2
1.6
0.1
0.0
0.0
0.0
0.0
1.1
5.3
7.5
36.1
12.3
11.2
8.0
4.4
1.0
0.0
0.0
0.0
0.1
1.0
5.4
10.3
53.6
9.4
8.9
4.5
2.1
0.1
0.0
0.0
0.0
0.0
0.8
4.9
7.6
38.3
8.5
7.5
3.5
1.9
0.2
0.0
0.0
0.0
0.0
0.7
4.1
6.5
33.0
7.4
7.4
2.9
1.1
0.1
0.0
0.0
0.0
0.0
0.3
3.0
6.9
29.1
Edinburgh
airport
Glasgow
airport
Aberdeen
airport
Manchester
airport
Cardiff
Greenwich
(London)
49.0
72.9
106.3
140.7
186.9
179.1
179.2
160.6
124.8
97.7
68.1
40.6
1405.8
34.4
58.5
87.4
130.8
178.6
168.0
160.3
144.8
113.4
81.2
52.5
29.8
1239.6
56.4
77.1
114.1
145.8
188.5
166.2
164.9
163.4
122.1
99.2
65.1
46.2
1409.0
49.6
67.0
95.2
138.9
188.8
172.5
183.8
170.5
127.2
97.7
60.6
42.8
1394.5
50.8
70.6
107.6
161.7
189.1
184.2
203.4
193.1
147.0
99.5
66.3
44.6
1518.0
45.9
66.1
103.2
147.0
185.4
180.6
190.3
194.4
139.2
109.7
60.6
37.8
1461.0
Edinburgh
airport
Glasgow
airport
Aberdeen
airport
Manchester
airport
Cardiff
Greenwich
(London)
64.2
44.7
52.2
42.5
49.1
52.5
57.6
53.3
62.4
69.5
61.4
66.8
676.2
141.7
99.2
109.5
60.2
62.8
63.1
68.3
84.1
116.4
131.8
130.6
137.6
1205.3
74.1
53.7
59.8
61.2
56.7
59.5
60.3
65.7
76.7
87.7
84.2
76.9
816.3
71.5
51.8
64.0
49.1
53.8
66.8
59.5
70.9
69.9
86.0
81.9
81.4
806.6
119.3
91.0
89.3
64.7
65.0
65.9
60.5
89.9
103.6
117.4
117.2
128.0
1111.7
51.9
34.0
42.0
45.2
47.2
53.0
38.3
47.3
56.9
61.5
52.3
54.0
583.6
(d) Hours of sunshine
January
February
March
April
May
June
July
August
September
October
November
December
Year
(e) Rainfall (mm.)
January
February
March
April
May
June
July
August
September
October
November
December
Year
(f) Rain days (days with 1 mm. or greater rainfall)
Edinburgh
airport
Glasgow
airport
Aberdeen
airport
Manchester
airport
Cardiff
Greenwich
(London)
12.2
9.1
10.8
8.3
9.1
8.5
9.0
9.4
10.3
11.8
10.7
11.5
120.7
17.2
13.6
15.3
10.7
11.0
10.8
11.2
12.1
14.5
16.0
16.2
16.6
165.2
12.6
9.5
11.2
11.0
9.7
9.6
10.9
10.9
10.8
12.8
13.1
12.1
134.2
13.6
10.1
12.1
10.5
10.1
11.5
10.0
11.0
11.3
13.2
13.6
13.4
140.4
16.1
11.8
13.5
10.3
10.5
9.9
8.9
10.6
11.3
14.2
13.9
15.0
146.0
10.9
8.1
9.8
9.3
8.5
8.4
7.0
7.2
8.7
9.3
9.3
10.1
106.5
January
February
March
April
May
June
July
August
September
October
November
December
Year
10.8
Although Edinburgh tends to be cooler than cities further to the south and west, it is less cloudy
than Glasgow and Manchester, and records more hours of sunshine. In fact it enjoys only 4%
fewer hours of sunshine than London, and has more sunshine than London over the winter
months (November to March). In November Edinburgh has more sunshine than any of the other
five comparator cities. May is the sunniest month in Edinburgh, followed by June and July.
This contrasts with London, where August is the sunniest month.
10.9
With less cloud cover, Edinburgh is also a relatively dry city. It has only 56% of Glasgow’s
annual rainfall, 61% of Cardiff’s, and 84% of Manchester’s. However it has 16% more than
London. Over the course of a typical year, rain falls on about 1 in 3 days in Edinburgh. Again,
this is significantly less than in the other selected cities, apart from London. October, December
and January are generally the wettest months. April, February and May are the driest.
Local climatic variations
10.10 While the figures in Table 1 give a reasonably representative picture of climatic conditions, it is
important to note that weather and climate will be far from uniform, even within the relatively
compact boundaries of Edinburgh. In fact there will be a wide variety of microclimates
governed by factors such as altitude, topography, local vegetation cover and land uses.
Edinburgh extends from sea level to an altitude of nearly 500 metres in the Pentland Hills, with
the highest areas of significant settlement being just short of 200 metres (at Buckstone and
Swanston). (Further details on Edinburgh’s topgraphy are given in chapter 11).
10.11 While the foghorn is sounding in the midst of a ‘haar’ at Leith harbour, the southern suburbs may
be basking in sunshine. Equally, there may be days when commuters from the south of the city
have to contend with snow or ice, while there may be little more than sleet to the north of Princes
Street. Although Edinburgh is a relatively small city, there may nevertheless be a modest ‘heat
island’ effect due to the local concentration of domestic and commercial energy consumption (see
chapter 7). However, there is no clear evidence on this.
Recent climatic trends
10.12 Observations from meteorological stations in and around Edinburgh, which have been collected
over a long time period, give an insight into longer-term changes in the local climate. The
Meteorological Office normally determines climatic characteristics on the basis of 30 year
averages for standard decades. Hence the current climate is described in terms of averages for
the period 1971 to 2000.
10.13 In addition to the data for individual observing stations, the Meteorological Office, in conjunction
with the Hadley Centre for Climatic Research, has created sets of time series data for the whole
of the UK, based on national grid squares. These give data for individual years, derived from all
observations in and around each 5 km. x 5 km grid square across the country. Graphs 1 to 4
below portray some of the trend data for Edinburgh, in the form of ‘moving averages’ for mean
daily maximum temperature, total monthly rainfall, the number of ‘wet’ days, and the number of
days with snow lying. The figures for temperature and rainfall are for four representative months
(January, April, July and October), and relate to the grid square covering the main urban area of
Edinburgh (south west corner grid ref. 32500 67000). For any given date on Graphs 1 and 2, the
value shown is the average for the previous 30 years – i.e. the usual time span for climatic data.
Graphs 3 and 4 are based on shorter time seies and adopt shorter moving average periods.
10.14 Graph 1 shows that July temperatures rose by about 0.80 C during the final two decades of the 20th
century, breaking through the level recorded during the previous period of warm summers in the
1940s and 1950s. Januarys have also been getting milder, albeit more gradually, and still not
quite reaching historic levels achieved during the 1930s / 40s. In contrast, the records indicate
that April and October in Edinburgh have been getting slightly cooler since reaching a high point
in the 1940s / 50s. However, towards the very end of the century there were signs that April
temperatures were starting to pick up again.
10.15 Graph 2 shows that April rainfall has remained fairly stable, but July rainfall has fallen by about a
third over the last 50 years. January and October rainfall appear to have been increasing slowly
since the 1970s following an earlier decline. However, the October figure is still below the level
which prevailed in the early to mid 20th century. These trends are mirrored in Graph 3 which
shows the prevalence of ‘wet’ days, i.e. days with 10mm or more of rainfall. This confirms that
autumns and winters are experiencing increased intensity rainfall. The period of most intense
rainfall now appears to be shifting from summer towards autumn. (n.b. data on wet days is only
available since 1961 and trends have been shown for a moving 20 year average rather than 30
years).
10.16 Graph 4 shows that there has been a very distinct drop in the number of days with snow lying in
Edinburgh – falling from 15 to 10 in just a decade (n.b. based on 15 year averages, because of
limited period of data coverage).
January
April
July
October
1998
1993
1988
1983
1978
1973
1968
1963
1958
1953
1948
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
1943
degrees centigrade
Graph 1 : Edinburgh climatic trends : mean daily maximum temperatures
for selected months (moving 30 year averages)
Graph 2 : Edinburgh climatic trends : monthly rainfall totals for selected
months (moving 30 year averages)
100
90
80
millimetres
70
60
50
40
30
20
10
January
April
July
1998
1993
1988
1983
1978
1973
1968
1963
1958
1953
1948
1943
0
October
Graph 3 : Edinburgh climatic trends : number of 'wet' days (moving 20
year averages)
6
5
3
2
1
Jan to Mar
Apr to Jun
Jul to Sep
Oct to Dec
1998
1993
1988
1983
1978
1973
1968
1963
1958
1953
1948
0
1943
days
4
Graph 4 : Edinburgh climatic trends : number of days with snow lying at
9.00 a.m., November to April (moving 15 year average)
16
14
12
days
10
8
6
4
2
1998
1993
1988
1983
1978
1973
1968
1963
1958
1953
1948
1943
0
November to April
Future climate change scenarios
10.17 Future scenarios for climate change across the UK have been researched under the UK Climate
Impacts Programme (UKCIP02). These consider four alternative atmospheric emissions trends
(low, medium / low, medium / high, and high) over three time periods (2011 to 2040, 2041 to
2070, and 2071 to 2100), with a degree of disaggregation to different regions. The projections
for the ‘high emissions’ scenario in relation to Scotland have been summarised in a report
published by the Scotland & Northern Ireland Forum for Environmental Research (SNIFFER :
‘Business Risks of Climate Change to Public Sector Organisations in Scotland’, November
2005). These are shown in the attached Table 3. More detailed projections for the Lothians
and the Scottish Borders area are shown in Table 4.
10.18 In very broad brush terms, the changes which can be expected in Edinburgh are :
• An overall increase in temperature, with hotter summers and warmer winters;
• Increased rainfall in winter but less in summer;
• An increase in extreme climatic events such as storms and flash floods; and
• More seasonal variation, with an increase in the number of very hot days in summer and a
decrease in the number of very cold days in winter
These predictions accord with the evidence from recent climatic records, which confirm that such
changes are already under way.
Table 3 : Descriptive climate projections for Scotland
(UKCIP02 ‘High Emission’ Scenario)
Variable
Projected trends, based on high emission scenario for 2080
Temperature
Warming of 0.3 to 0.50C per decade is expected.
Confidence
level
High
Greatest warming (+3.5 to +4.50C) in autumn across the whole of the
country bar the extreme north.
More marked seasonal differences between summer / autumn and
winter.
Precipitation
Winter precipitation increases by 20-35% in the south, east & north
east.
High
Summer precipitation decreases by 30-50% in south, central & east
Scotland.
Larger differentiation between the drier summer & wetter winter
seasons.
With regard to temperature, winter and spring become less variable by
up to 25%; however, the inter-annual variability is increased in
summer by 25% across south Scotland, and in autumn by 15-25% in
nearly all of Scotland.
High
With regard to precipitation, there is a reduction in intra-annual
variation in summer across almost all of Scotland, reaching 30% in
south, central & west Scotland.
Low
Cloud cover
Slight decrease in summer cloud cover, excepting the extreme north &
north west; slight increase in winter cloud cover in some northerly
areas
Low
Humidity
Relative humidity decreases slightly across the whole of Scotland in
spring and summer, and across all of Scotland bar the extreme north
& north west in autumn and winter
Medium
Snowfall
All of Scotland will receive at least 50% less snowfall than in winters
at present, and over 70% less in the eastern half of the country
Medium
Soil
moisture
The highest changes are in summer & autumn, with a reduction in soil
moisture in summer & autumn of 10-40% in all of Scotland bar the
Highlands.
High
Soil moisture levels are higher than present in winter, with an increase
of 0-10% over most of Scotland.
Medium
Variability
Precipitation
intensity
Increases in winter
High
Temperature
extremes
Number of very hot days increases, especially in summer & autumn.
High
Wind speed
Daily mean wind speed with a 2 year return period will increase
slightly in winter and decrease in summer.
Low
Thermal
growing
season
Increases everywhere
High
Marine
climate
Sea surface temperature will increase around all Scottish coasts
High
Number of very cold days decreases, especially in winter.
Source : UKCIP02 / SNIFFER
Table 4 : Temperature and rainfall projections for South East Scotland
Table 3(a) : Low Emissions Scenario
Variable
Season
2020s
2050s
2080s
Temperature (0C)
Winter
+ 0.0 to 1.0 0C
+ 0.5 to 1.0 0C
+ 1.0 to 1.5 0C
Spring
+ 0.5 to 1.0 0C
+ 1.0 to 1.5 0C
+ 1.5 to 2.0 0C
Summer
+ 0.5 to 1.0 0C
+ 1.0 to 1.5 0C
+1.5 to 2.0 0C
Autumn
+ 0.5 to 1.0 0C
+ 1.0 to 1.5 0C
+ 2.0 to 2.5 0C
Winter
0% to + 10%
0% to + 10%
+ 10% to + 15%
Rainfall (% change)
Spring
0%
0%
0%
Summer
0% to - 10%
- 10% to - 20%
- 20% to - 30%
Autumn
0%
0%
0%
Table 3(b) : Medium / Low Emissions Scenario
Variable
Season
2020s
2050s
2080s
Temperature (0C)
Winter
+ 0.5 to 1.0 0C
+ 1.0 to 1.5 0C
+ 1.0 to 1.5 0C
Spring
+ 0.5 to 1.0 0C
+ 1.0 to 1.5 0C
+ 1.5 to 2.0 0C
Rainfall (% change)
0
0
Summer
+ 0.5 to 1.0 C
+ 1.5 to 2.0 C
+2.0 to 2.5 0C
Autumn
+ 0.5 to 1.0 0C
+ 1.5 to 2.0 0C
+ 2.0 to 2.5 0C
Winter
0% to + 10%
0% to + 15%
+ 10% to + 20%
Spring
0%
0%
0%
Summer
0% to - 10%
- 10% to - 20%
- 20% to - 30%
Autumn
0%
0%
0%
2050s
2080s
Table 3(c) : Medium / High Emissions Scenario
Variable
Season
2020s
Temperature (0C)
Winter
+ 0.5 to 1.0 0C
Rainfall (% change)
0
+ 1.0 to 1.5 0C
0
+ 2.0 to 2.5 0C
Spring
+ 0.5 to 1.0 C
+ 1.0 to 1.5 C
+ 2.5 to 3.0 0C
Summer
+ 0.5 to 1.0 0C
+ 1.5 to 2.0 0C
+3.0 to 3.5 0C
Autumn
+ 0.5 to 1.0 0C
+ 1.5 to 2.0 0C
+ 3.0 to 3.5 0C
Winter
0% to + 10%
+ 10% to + 15%
+ 15% to + 25%
Spring
0%
0%
0%
Summer
0% to - 10%
- 10% to - 30%
- 30% to - 40%
Autumn
0%
0%
0%
Table 3(d) : High Emissions Scenario
Variable
Season
2020s
2050s
2080s
Temperature (0C)
Winter
+ 0.5 to 1.0 0C
+ 1.0 to 1.5 0C
+ 2.0 to 3.0 0C
Spring
+ 0.5 to 1.0 0C
+ 1.5 to 2.0 0C
+ 2.5 to 3.5 0C
Summer
+ 0.5 to 1.0 0C
+ 2.0 to 2.5 0C
+3.5 to 4.0 0C
Rainfall (% change)
Autumn
+ 0.5 to 1.0 C
+ 2.0 to 2.5 C
+ 4.0 to 4.5 0C
Winter
0% to + 10%
+ 10% to + 20%
+ 20% to + 30%
Spring
0%
0%
0%
Summer
- 10% to - 20%
- 20% to - 30%
- 40% to - 50%
Autumn
0%
0%
0%
Source : UKCIP02 / SNIFFER
Scenarios in October 2008)
0
0
(n.b.UKCIP are expected to release revised UK Climate Change
Implications of climate change
10.19 Table 2 highlights some of the ways in which climatic conditions affect day-to-day activities in
Edinburgh. These give just a small indication of how climate change could impact on everyday
life.
Table 2 : Potential local effects of climatic change
Temperature
Rainfall
• Lower winter heating demand but increased
summer cooling & refrigeration requirement
• Poorer summer air quality - potential
respiratory problems; winter air quality may
improve
• Fewer burst pipes in winter
• Summer tourism benefits
• Effects on range of species and biodiversity,
through changing habitats, food supplies etc.
(different levels in food chain may adapt at
different rates to climatic changes)
• Landscape planting / maintenance effects
• Spread of insect and other pests, e.g. midges
• Higher incidence of bacterial infections, food
poisoning; risk of heat exhaustion, skin cancer
• Road surfacing more liable to melting
• Smells from decaying refuse
•
Wind
Fog, snow etc.
• Closure or restrictions on Forth Road Bridge
• Disruption of flights at Edinburgh airport
• Falling trees & branches – road closures and
risk to people & property
• Disruption to overhead power lines
• Falling masonry, scaffolding etc.; higher
building maintenance costs
• Scattering of uncontainerised litter & detritus
•
•
•
•
•
•
•
•
•
•
•
Flooding of residential & commercial
property – expenditure on flood prevention
schemes; higher insurance premiums
Flooding – disruption of transport networks
Drains & gullies blocked more frequently
Disruption to construction projects
Higher risk of subsidence / rock falls
(resulting from warmer, drier summers &
wetter winters)
Poorer water quality; water-borne spread of
pollutants / sewage
Damp properties & respiratory diseases
Reduced certainty over water supplies in
summer – potential periods of shortfall
Summer grass fires – Arthur’s Seat etc.
Risk to winter outdoor events, festivals etc,
Motoring accidents
Lower gritting requirement
10.20 The closure of the Forth Road Bridge to high-sided vehicles provides a good illustration of the
disruption that can be caused by changing weather patterns. Although Graph 5 only covers the
last 6 years, it does tend to suggest that there has been a trend towards more lengthy and more
frequent closures due to high wind speeds (but with significant variations from year to year).
Graph 5 : Forth Road Bridge – Annual Number of Hours Closure to High-Sided Vehicles
due to High Wind Speeds
300
260
250
187
200
150
114
100
50
0
54
44
24
2001 / 2
2002 / 3
2003 / 4
2004 / 5
2005 / 6
2006 / 7
source : Forth Estuary Transport Authority, reported in Edinburgh Evening News 8th Feb. 2008 Note : the Forth Road Bridge is
closed to high-sided vehicles when wind speeds exceed 50 mph, and closed to all vehicles when wind speeds exceed 85 mph.
10.21 A number of studies have looked in some detail at the potential repercussions of climate change
at the national and international level (see Sources and Further Information). Particularly
significant and influential among these was the ‘Stern Review’, commissioned by the UK
Government Treasury, which considered the economic impacts of climate change (published
2006). This concluded that, without urgent action, climate change could lead to a deep and
sustained world-wide economic recession, with all the consequences that would flow from that.
Hence it will make sound economic sense to tackle the issue pro-actively rather than re-actively,
implementing appropriate mitigation and adaptation measures at the earliest opportunity. This
will inevitably entail major changes in priorities, lifestyles and technologies, underpinned by
substantial investment.
10.22 Whilst these are very real and serious challenges, climate change and the response to that change
can also have positive economic effects, provided the opportunities are seized. For example
these might materialise through :
• warmer and drier summers supporting an expansion and diversification of tourism (but only
if this is achieved without additional unsustainable travel)
• greater agricultural and horticultural productivity (subject to adequate water supplies), with
wider range of products grown locally, and reduced transport costs;
• the establishment of a ‘centre of excellence’ for sustainable businesses devoted to small scale
renewable energy generation, energy conservation, recycling etc.
• financial savings stemming from conservation and recycling of resources (energy and
materials)
Greenhouse gas emission reduction targets
10.23 Reductions in the atmospheric concentrations of ‘greenhouse gases’ are the key to arresting
climate change. To this end, the world community and individual nations have recently devoted
considerable effort to agreeing appropriate targets for reducing emissions of such gases. This
will have implications across the whole spectrum of human activities, including power
generation, buildings, transport, consumer goods, land use changes etc.
10.24 The most recent review of research presented by the Intergovernmental Panel on Climate Change
indicates that world greenhouse gas emissions need to be reduced to between 50 and 85% below
year 2000 levels in order to stabilise atmospheric concentrations of greenhouse gases and most
likely limit warming to between 2.0 and 2.4˚C. (IPCC Climate Change 2007 : Synthesis
Report)
10.25 Current international and national targets for emission reductions are summarised in Table 3.
Table 3 : International and National Greenhouse Gas Emission Targets
Kyoto Protocol – international
(leading industrial nations)
5.2% reduction on 1990 levels by 2008 – 2012.
European Union
minimum 20% reduction on 1990 levels by 2020
‘Road map’ agreed at Bali conference in Dec. 2007 to
negotiate new international commitments beyond 2012; to
be agreed by end of 2009
agreed by EU Council March 2007, with expectation of
setting higher 30% target subject to international agreement
UK Government
60% reduction on 1990 CO2 emissions by 2050, with
interim reduction of 26-32% by 2020
proposed in draft UK Climate Change Bill, 2007
Scottish Government
80% reduction on 1990 CO2 emissions by 2050
Proposed in draft Scottish Climate Change Bill, 2008
source : Scottish Government : Consultation on a Scottish Climate Change Bill, Jan. 2008
10.26 Within Scotland, carbon dioxide accounts for approximately 80% of greenhouse gas emissions.
However, there are a number of other greenhouse gases whose atmospheric concentrations have
increased significantly over the last century. As Table 4 shows, although occurring in lower
concentrations than carbon dioxide these have a disproportionate warming effect, partly because
of their ability to absorb radiation and partly because of their longer residence time in the
atmosphere.
Table 4 : Relative Global Warming Potential (GWP) of Greenhouse Gases
Carbon dioxide (CO2)
Methane (CH4)
Nitrous oxide (N2O)
1
21
310
Hexafluorocarbons
140 – 11,700
Perfluorocarbons
6,500 – 9,200
Sulphur hexafluoride (SF6)
23,900
source : Scottish Government : Consultation on a Scottish Climate Change Bill, 2008 based on UN Framework Convention on Climate
Change
note : Global Warming Potential is measured in CO2 equivalents and relates to total warming effect over a 100 year period.
Scottish Climate Change Bill
10.27 The former Scottish Executive acknowledged the potentially serious consequences of climate
change when it introduced a national programme for tackling the causes (mitigation) and
preparing for the consequences (adaptation) in March 2006 (‘Changing our Ways : Scotland’s
Climate Change Programme’)
10.28 The new Scottish Government has concluded that the required level of commitment and scale of
change is sufficient to warrant legislative changes which take full account of the circumstances
particular to Scotland. In January 2008 it published a consultative draft of its proposals for a
Scottish Climate Change Bill. This is intended to provide a clear long-term enabling framework
to support a wholesale shift towards a low carbon economy. It signals a determination that
Scotland will pull its full weight in the global effort to tackle climate change.
10.29 The proposals include setting a statutory target of an 80% reduction in greenhouse gas emissions
by 2050 (relative to 1990 base levels for CO2, CH4 and N2O). This is considered to be
ambitious but achievable. It goes beyond the 60% reduction target set out in the UK Climate
Change Bill, which was introduced to the UK Parliament in November 2007. However, various
options are still being explored as to how exactly such a target will be measured. The adoption
of a more stringent emissions target will require updating of the current programme for tackling
climate change set out in “Changing Our Ways”.
10.30 In order to ensure steady progress towards the 2050 target, and to reduce cumulative impacts, the
government also proposes to introduce a system of emissions budgeting. This will set limits on
total greenhouse gas emissions in each budgeting period (e.g. 5 years), whilst allowing flexibility
from year to year within each period. Budgets would be set in advance and would reduce over
time. On average, emissions would need to fall by at least 3% per annum to hit the 80%
reduction target. The government recognises that a comprehensive reporting system will need
to be put in place to monitor progress and to hold ministers to account.
10.31 The proposed Bill will ensure that the necessary legal powers are in place to give real ‘bite’, not
only to mitigation efforts but to adaptation measures as well (i.e. measures to ensure that Scotland
is well prepared to cope with unavoidable climate change). A consultative Scottish Adaptation
Strategy is due to be published in the Spring of 2008.
10.32 The consultation document recognises the important role of local authorities and other large
public agencies in helping to steer towards a low carbon economy. For the time being the
government appears content that satisfactory progress can be made through voluntary initiatives,
such as those stemming from ‘Scotland’s Climate Change Declaration’ (summarised below).
However, it is also considering whether some specific duty or duties might need to be introduced
at a later stage – for example an obligation on local authorities to meet agreed targets, take
account of climate change impacts in all policies and procurement decisions, and report regularly
on progress.
10.33 One further approach being considered is the potential for local authorities to use differential
charging to promote behaviours which reduce impacts on the climate – for example lower
parking charges for vehicles with smaller engines. In some cases, changes in legislation might
be required to confer enabling powers.
10.34 In November 2007 the Scottish Government announced plans for a package of measures to
support local authorities in discharging their commitment under the Climate Change Declaration
and the proposed Scottish Climate Change Bill. These include :
• a Climate Change Tools database, which will guide councils to the most appropriate solutions
in tackling climate change, from a comprehensive list of mitigation and adaptation responses;
• pilot Local Climate Impact Profiles, which will help to develop understanding of the local
opportunities and threats from a changing climate.
Local action on climate change
10.35 In January 2007 the City of Edinburgh Council joined with the other 31 Scottish local authorities
in signing Scotland’s Climate Change Declaration. This acknowledges the reality and
importance of climate change and commits its signatories both to mitigate future impacts and to
adapt to changes which are already under way. Further details are available on the web site of
the Sustainable Scotland Network (www.sustainable-scotland.net/climatechange). The
Declaration is intended to spur progress towards national targets set out in ‘Changing Our Ways’
– Scotland’s Climate Change Programme (SCCP) (Scottish Executive, March 2006).
10.36 A requirement of the Declaration is that each signatory should produce and publicly declare a
plan, with targets and time-scales, to achieve a significant reduction in greenhouse gas emissions
from its own operations. There is a further requirement to ensure that measures to reduce
greenhouse gas emissions and adapt to the impacts of climate change are incorporated within all
strategies and programmes affecting the local area; also to work with other local agencies to
achieve the same end.
10.37 To fulfil these requirements the City of Edinburgh Council has drafted a ‘Climate Change
Framework’ which is currently at consultation stage. This identifies a number of measures
which are already under way to address climate change. It seeks to co-ordinate these within a
single strategy framework, and to augment them with new initiatives which will work in harmony
with each other. The Climate Change Framework will be a key component in a wider
Sustainable Development Strategy for Edinburgh, which will be launched in 2008.
10.38 Chapters 7 and 8 in this report gives further information on Edinburgh’s energy and carbon
budgets. These directly affect greenhouse gas emissions and therefore have significant
consequences for climate change.