Climate change in Perth & Kinross
Weather or climate?
The term weather refers to day to day or year
to year variations in conditions. The term
climate, on the other hand, refers to average
conditions usually taken over a 30 year period, allowing trends and
patterns to be detected.
Recent climate change?
There is evidence that the Scottish climate is already
changing.
- It is getting warmer overall
- Summers are becoming drier, though there are some important
regional variations
- Winters are becoming wetter and generally milder
- On average, there are fewer days with lying snow
- The growing season is getting longer
If you want to find out more about recent climate change a full
digest of trends is available online at by using the link on
the right hand side of the page.
How is the climate predicted to change?
The latest UK Climate Projections were published in 2009 and are
known as UKCP09. It is important to recognise these are not
predictions, they are projections based on the best available
knowledge.
The projections are complex they cover different time periods
(thirty year slices from now until the end of the century),
different levels of carbon emissions (reflecting the extent to
which we manage to reduce emissions from fossil fuels), and
different levels of probability (from changes that only have a 5 or
10% probability of occurring, but which could be major, to changes
that have a 90 or 95% probability of occurring).
The key messages emerging from the data are that:
- Summers will become hotter and drier
- Winters will become milder and, in most parts of Scotland,
wetter
- Coastal areas will experience sea level rise, changing patterns
of erosion and deposition and increasing the risk of flooding from
exceptionally high tides.
These projections are in line with the trends already recorded
across Scotland.
What are the predicted changes in temperature and rainfall
likely to be in this area?
The UKCP09 projections are complex ? they cover different time
periods (thirty year slices from now until the end of the century),
different levels of carbon emissions (reflecting the extent to
which we manage to reduce emissions from fossil fuels), and
different levels of probability (from changes that only have a 5 or
10% probability of occurring to changes that have a 90 or 95%
probability of occurring). The tables below are based on high
carbon emissions (reflecting where we are at the moment) and taking
the 10% (very unlikely), 50% (as likely to happen as not) and 90%
(very likely) probability levels.
In the tables below the numbers in bold represent
the mid point of the probability range, know as the central
estimate. Taking the Carse of Gowrie as an example, there is a 50%
chance the summer mean temperature will be more than 1.2 degrees C
hotter and a 50% chance it will not have increase quite that much.
The figures in brackets show the range within which the actual
change is likely to be. In this case, the projections suggest that
it is very unlikely the increase in summer average temperature will
be less than 0.6 degrees C or greater than 1.9 degrees C in the
2020s.
This information can be extremely useful in helping
organisations plan how they will adapt to a changing climate.
UKCP09 data is provided on a national, regional or river basin
level at a 25km grid square level. However, in order to
assist in understanding the projected future climate for this area
the key findings at a Perth and Kinross level are shown in the
tables below. If want to locate the grid squares on a
map you can use the Met Office grid locator where you can click on
an area of the map below to display the grid box id for a
particular area. The grid box id is the number used to identify the
grid boxes within the HadRM3 regional climate model.
We have taken the UKCP09 Climate change projections (high
emissions, 10%, 50% and 90% probability projections) for two
grid squares. The first covers a lowland area (729) in the east and
the second covers an upland area (649) in the west to give you an
idea of how the climate may change over time across Perth and
Kinross and at different altitudes. What they show is that
there will be variabliity over the area.
Where is the lowland square?
The lowland square (729) is in the Carse of Gowrie area.
The time periods used were the 2020s, 2050s, and 2080s; for all
three emissions scenarios (low, medium and high); and for
summer and winter in the time period. Various variables were
used to produce the key findings, and these are summarised in the
table below:
Carse of Gowrie (Grid quare 729)
|
UKCP09 Climate Projections |
| Climate Variable |
2020s |
2050s |
2080s |
| Mean Annual Temperature (°C) |
1.2
(0.6 to 1.9) |
2.0
(1.2 to 3.0) |
2.8
(1.7 to 4.2) |
| Mean Annual Precipitation (%) |
-0.4
(-5.4 to 5.0) |
-1.2
(-7.4 to 5.4) |
-0.9
(-8.6 to 7.3) |
| Mean Winter Precipitation (%) |
-0.4
(-5.4 to 5.0) |
-1.2
(-7.4 to 5.4) |
-0.9
(-8.6 to 7.3) |
| Mean Summer Temperature (absoloute) |
14.9
(13.7 to 15.7) |
15.7
(14.1 to 17.0) |
16.8
(14.6 to 18.6) |
| Mean Summer Daily Maximum Temperature |
19.4
(17.7 to 20.6) |
20.4
(18.0 to 22.3) |
21.7
(18.4 to 24.4) |
| Mean Annual Temperature |
9.2
(8.4 to 9.8) |
9.9
(8.9 to 10.8) |
10.7
(9.3 to 11.8) |
| Mean Winter Temperature (absoloute) |
3.9
(2.7 to 4.7) |
4.5
(3.2 to 5.4) |
5.0
(3.4 to 6.2) |
| Change in Temperature of Coldest Night
of Winter |
0.8
(-1.3 to 2.2) |
1.4
(-1.2 to 3.1) |
1.3
(-2.0 to 3.5) |
| Change in Temperature of Warmest Day of Summer |
1.0
(-3.3 to 4.0) |
2.4
(-2.8 to 6.2) |
3.7
(-3.0 to 8.7) |
Where is the upland grid square?
The upland grid square (649) covers Ben Lawers.
The time periods used were the 2020s, 2050s, and 2080s; for all
three emissions scenarios (low, medium and high); and for
summer and winter in the time period. Various variables were
used to produce the key findings, and these are summarised in the
table below.
Ben Lawers (Grid Square 649)
|
UKCP09 Climate Projections |
| Climate Variable |
2020s |
2050s |
2080s |
| Mean Annual Temperature (°C) |
1.3
(0.7 to 2.0) |
2.1
(1.3 to 3.2) |
3.0
(1.8 to 4.4) |
| Mean Annual Precipitation (%) |
-0.6
(-4.9 to 3.8) |
-1.5
(-6.3 to 3.4) |
-2.2
(-7.9 to 3.5) |
| Mean Winter Precipitation (%) |
2.1
(-4.1 to 8.8) |
4.8
(-2.1 to 12.4) |
5.7
(-1.7 to 14.5) |
| Mean Summer Temperature (absoloute) |
13.0
(11.8 to 13.8) |
13.8
(12.2 to 15.2) |
14.9
(12.7 to 16.8) |
| Mean Summer Daily Maximum Temperature |
17.3
(15.6 to 18.6) |
18.4
(16.0 to 20.4) |
19.8
(16.3 to 22.5) |
| Mean Annual Temperature |
7.3
(6.5 to 8.0) |
8.1
(7.0 to 9.0) |
8.9
(7.4 to 10.1) |
| Mean Winter Temperature (absoloute) |
2.5
(1.1 to 3.3) |
3.1
(1.6 to 4.2) |
3.6
(1.8 to 5.0) |
| Change in Temperature of Coldest Night
of Winter |
1.4
(-1.8 to 3.5) |
2.4
(-17 to 5.1) |
2.3
(-3.2 to 5.9) |
| Change in Temperature of Warmest Day of Summer |
0.8
(-.04 to 1.6) |
1.3
(0.0 to 2.2) |
1.9
(-0.5 to 3.1) |
Where can I get more information?
You can get more information on the observed changes in the
climate from the Met Office web site by using the link on the
right of this page. If you want more information about the
climate change projections you can use the link on the right of the
page.
