Download Trees and Climate Change

1 Introduction and key messages
The purpose of this pack
This pack presents the Forestry
Commission’s key messages on climate
change. It draws together the
information available from the Forestry
Commission, Forest Research and other
relevant organisations, to explain in one
document the role of trees, woods and
forests in tackling climate change.
Who is this pack aimed at?
The pack is primarily aimed at Forestry
Commission staff, so that they are able
to communicate the Forestry
Commission’s key climate change
messages to the public.
Key messages: a summary
Trees, woods and forests can provide
part of the solution to limiting climate
change, and to helping society to
adapt to the changes that we all face.
We must help our trees, woods and
forests to adapt and become resilient
to the changing climate.
• Climate change resulting from
human activity is a reality. Forests
and forestry can be an important
and attractive part of the solution.
• On a global scale, we must protect
and manage the woods and forests
that we already have as well as
planting new forests, to “mitigate”
climate change.
• Cutting down trees is not always
bad for the environment. As long as
woodlands are managed in a
sustainable way, there can be a
multitude of benefits: for the
climate, for people and for wildlife.
• Wood is a smart choice. Timber is
renewable and can replace other
materials that require much larger
fossil fuel inputs for their production.
It can also replace fossil fuels
directly in the form of renewable
energy, or wood fuel.
• Trees can help us to adapt to a
changing climate. They provide
shade, alleviate flooding, and
create a valuable wildlife habitat.
• Our forests are changing due to
climate change and we need to
plan ahead to help them adapt.
The Forestry Commission is working to
provide the answers and best
practical solutions based on sound
evidence. Through its management
of the public forest estate, and its
research and promotional work, the
Forestry Commission is already
playing an important role in
combating climate change, and in
helping our forests adapt to the
changing climate.
This pack provides more information about each of these key messages.
The Convenient Truth
The "A Convenient Truth" pack and DVD
produced by the Forestry Commission in
2007, breaks these messages down
into six actions that we can take:
Protect what we already have
Reduce deforestation
Restore the world’s forest cover
Use wood for energy
Replace other materials with wood
Plan to adapt to our changing climate.
A note about sustainable living
Living sustainably by reducing waste,
recycling, reducing consumption and
generally adopting a “greener
lifestyle” are all really important ways
in which we can reduce our impact on
the environment. However,
sustainable living is dealt with
extensively elsewhere
by other organisations, and the
messages are not unique to the
Forestry Commission. Therefore this
document focuses on the unique role
of the Forestry Commission in terms of
trees, woods, forests and climate
change.
What do the British public think about forests and climate
change?
The Public Opinion of Forestry Survey
2007 included questions about
climate change, and the answers
identified clear areas that required
more communication. For example:
• 62% of people said that cutting
down trees and forests makes
climate change worse, even if they
are replanted. A further 24% were
unsure.
• Only 41% of people thought that
using wood as a building material
was better for climate change than
concrete or steel.
• 46% of people thought that using
wood as a fuel makes climate
change worse because it releases
carbon dioxide to the atmosphere.
• 25% of people thought that trees
should not be felled in any
circumstances, even if they are
replaced.
The full survey can be found at:
www.forestry.gov.uk/statistics. Some
of the misconceptions identified by
this report have helped to shape the
information provided in this pack. This
should arm Forestry Commission staff
with the information required to
address common questions or
concerns about these subjects.
Climate change as a result of human
activity is a reality. Forests can be an
important and attractive part of
the solution
2 Some background information
We are experiencing climate change because human activities continue to release
greenhouse gases such as carbon dioxide into the atmosphere. Forests are part
of the cause of climate change because globally deforestation contributes to
nearly 20% of carbon dioxide emissions. However, forests can be an important
part of the solution if we can reverse deforestation and plant new forests to
absorb carbon dioxide from the atmosphere.
Human impact
Earth’s climate has been relatively stable since the last glaciation, which ended
10,000 years ago
However it is generally agreed among scientists that we are now experiencing
climate change as a result of human activities that have taken place over the
last century or so
Since the industrial revolution, burning of fossil fuels and large-scale
deforestation have released greenhouse gases such as carbon dioxide and
methane into the atmosphere
These and other human activities mean that atmospheric concentrations of
carbon dioxide have risen by 40% over pre-industrial levels
Sun
Some energy is
reflected back
into space
Solar energy
from the sun
passes through
the atmosphere
and heats the
Earth’s surface
Some heat is
radiated back
out into space
Greenhouse
gases in the
atmosphere
trap some heat
keeping the
Earth warm
Atmosphere
Earth
Greenhouse gases occur naturally in the
atmosphere. Indeed the Earth would be
uninhabitable without them. The problem is
that levels of greenhouse gases have
increased due to human activity since the
1850s. Greenhouse gases in the Earth’s
atmosphere warm the Earth by preventing
heat escaping from the atmosphere back
into space.
Trees are a carbon store
Trees store carbon through photosynthesis
While they are growing, trees absorb
carbon dioxide from the atmosphere
through photosynthesis and store it as
carbon in the form of wood.
6 CO2
Carbon dioxide
from the
atmosphere
Facts and Figures
• Carbon dioxide is the most
important greenhouse gas in
terms of human activity. In the UK it
contributed to over 85% of total
greenhouse gas emissions in
2004.
• More carbon is stored in global
forest ecosystems than is
contained in all of the world’s
remaining oil stocks, or in the
atmosphere
• Deforestation alone currently
accounts for nearly 20% of global
carbon dioxide emissions. This is
greater than the whole transport
sector
• Soil contains the largest carbon
store in the UK with woodland soils
storing about 500 million tonnes of
carbon. This is in comparison to
the 150 million tonnes stored in
forest biomass.
+
6 H2O
C6H12O6 +
Water
Organic
matter
6 O2
Oxygen
Plants use carbon dioxide and water as raw materials during photosynthesis to produce
sugars. These sugars provide the energy required to for the production of cellulose, or lignin in
the case of woody plants – locking up carbon. Oxygen is produced as a by-product. Some of
the carbon dioxide is returned to the atmosphere through respiration. The remaining carbon is
stored in leaf, root, seed, wood and branch biomass.
What is the difference between carbon and carbon dioxide?
• Carbon is a chemical element with
the symbol C. It is the fourth most
abundant element in the universe
by mass after hydrogen, helium
and oxygen.
• Carbon dioxide is a gas at standard
temperature and pressure.
At the beginning of the 20th Century,
woodland covered only 5% of the UK’s
land surface. This is now up to 12% (8%
of England), and although still small in
• One tonne of carbon is equivalent
to 3.7 tonnes of carbon dioxide.
• One tonne of (oven-dried) wood
contains approximately half a tonne
of carbon. This is the equivalent of
1.85 tonnes of carbon dioxide.
global terms, the forests and
woodlands in the UK have an important
role to play. The work of the Forestry
Commission is vital.
Where does the carbon go?
CO2 in atmosphere
Decay of litter
releases CO2
Removal of CO2 from
atmosphere
Respiration adds CO2
to the atmosphere
Photosynthesis (gross
primary productivity)
Net primary production
– new biomass (i.e.
stem wood, roots,
branches, leaves, fruit)
A summary of the carbon exchange associated
with a typical woodland.
New litter input from
foliage, seeds, wood
Net increase in soil
carbon
Summary
• Earth’s climate is changing as a result of human activity
• Trees and forests and their products can be part of the
solution to combating climate change if they are well
managed, both on a global and a local scale
Climate change is a reality
3 What will climate change look like?
Climate change projections suggest that Britain will experience increasingly
warmer and drier summers, accompanied by milder but wetter winters.
There will also be more extreme weather events.
But it doesn’t feel warmer!
It is often difficult to reconcile the recent
cold, wet summers with the fact that the
ten warmest years on record have all
occurred since 1994. However, what
sticks in our minds is short term
weather rather than long term trends in
climate. We will probably see cold
periods lasting for a number of years
and apparent increases in summer
rainfall, but these will be blips within a
more general warming trend and a
tendency towards drier summers.
Climate change now and in the next
30-40 years is inevitable due to past
greenhouse gas emissions. Beyond this
timeframe, the amount of climate
change will be determined by the
emissions that we are producing now.
Weather and climate:
what’s the difference?
Weather describes atmospheric
conditions over a short time period,
and climate is how the atmosphere
"behaves" over relatively long time
periods. Climate change means
changes in the long-term averages
of daily weather.
Climate change in England - key facts
• Climate change is happening, and a further increase in
temperature of at least 2°C globally by 2100 is now
inevitable due to past emissions.
• We can expect a further rise in temperature of 2°C (above
the 1961 to 1990 baseline) by 2100 even if we decrease
our carbon dioxide emissions dramatically.
• If no action is taken now, the rise in temperature could be
as high as 7°C by 2100.
• The growing season has lengthened and trees are
coming into leaf up to three weeks earlier than in the
1950s (the study of phenology).
• Winters in the UK are likely to become wetter (by up to
30%) and summers drier. Areas of southern England are
likely to become subject to more frequent and severe
summer drought.
• Rainfall events are likely to become more intense.
• Sea level rise of between 1-10cm will occur around the UK
coast per decade over the next 100 years leading to a
decrease in land area.
Summary
• Climate change is happening and
an increase in temperature of at
least 2°C globally is now inevitable
due to past emissions
• Summers in the UK will be warmer
and drier, and winters warmer
and wetter
• Extreme weather events will
become more common
One of the key predicted impacts of climate
change is more extreme weather events. The
headline-hitting flooding events of the last
couple of years are certainly consistent with
this aspect of climate change, but we cannot
say that they are the result of climate
change.
Winter
18
Spring
Summer
Autumn
16
14
12
10
8
6
4
2
2005
1995
1985
1975
1965
0
1955
Climate change projections for the UK
are published by the UK Climate
Impacts Programme (UKCIP). Most
recent studies have used the scenarios
published in 2002 (UKCIP02). New
projections will be published in 2009.
These will provide more quantification
of uncertainty and the probability of
specific changes in climate happening.
Go to www.ukcip.org.uk for more
information.
20
Average Temperature (oC)
Arctic regions are especially sensitive to
warming and will see even larger
increases in temperature. This could
lead to the release of the huge
quantities of methane currently stored
beneath the Arctic. Methane is a
greenhouse gas 25 times more
powerful than carbon dioxide, and in a
positive feedback loop could lead to
further dramatic temperature rises.
Year
Temperature data has been recorded at Bedgebury Pinetum since 1960. Results so far show
a slow, steady rise in all seasons since recording began.
Our forests are changing due to
climate change and we need to plan
ahead to help them adapt
4 What does climate change mean
for forestry?
Our changing climate means increased uncertainty for the future, and hence
increased risk. We must plan ahead to help our forests adapt.
Potential impacts: a summary
Change expected
Beneficial effects
Negative effects
Increased carbon dioxide
Enhanced growth rates.
Water loss is reduced due to
closure of leaf pores.
Reduced timber quality unless different species are used to those
that we use currently.
Possible nutrient imbalances.
Reduced summer rainfall
Drought conditions become more severe and frequent – some tree
species no longer suitable for commercial forestry.
Stress caused by drought makes trees more susceptible to pests
and diseases.
Increased tree mortality – particularly street trees.
“Drought crack” reducing timber quality.
Increased winter rainfall
Waterlogging and reduced access for forest machinery.
Increased mortality of fine roots. In turn this can worsen the effects
of summer drought.
Infection by soil–borne diseases is increased by fluctuating water
tables.
Reduced stability and more wind throw.
Increased storm frequency
Greater storm damage.
Warmer temperatures
Longer growing season.
Increased potential productivity.
Lower risk of winter cold
damage.
Potential for use of tree species
that are not hardy enough to
thrive in Britain at present.
Leaves appearing earlier due to warmer temperatures can leave
trees vulnerable to frost damage.
Pests able to survive through winter.
Potential for exotic pests to spread to the UK.
Species that rely on the timing of each others life cycles could
become out of synchronisation with each other – e.g. flowers and
their pollinators.
Focus on:
Green spruce aphid
(Elatobium abietinum)
Green spruce aphid
Species suitability
Our changing climate is likely to result in
some tree species becoming less suited
to the areas in which they currently live,
and some becoming more suitable.
Woodland flora is also likely to suffer.
Some non native species may benefit
from climate change and could become
invasive in the future by out-competing
native species. Monitoring and record
keeping are essential to follow the
impacts of climate change and decide
what actions to take.
We must plan ahead to help our
woodlands adapt. See sheet 10 for
more information on adaptation.
Pests and diseases
Climate change will mean that:
1 Stressed trees are more susceptible
to insect pests and diseases
2 More pests will be able to survive
over winter and summer activity is
likely to increase – leading to
increased tree disease and damage
• Some insect pests that are currently
at low levels, or are not currently
considered a threat are likely to
become more prevalent.
• The effective range of existing pests
or pathogens may change, including
a northward expansion of those with
a southern distribution and the likely
appearance of some from continental
Europe
• The changing climate may be
increasingly favourable to a new
range of pests that are inadvertently
introduced through global trade.
This aphid defoliates Sitka spruce and
Norway spruce in the UK. At present, its
populations appear to be limited
primarily by cold winter temperatures
below –7°C and sudden frosts. Higher
temperatures will lead to higher
reproduction and growth rates, and will
allow more aphids to survive during the
winter.
Phytophthoras
Phytophthoras are a group of fungal
pathogens responsible for major plant
diseases in many parts of the world.
Phytophthora diseases can be expected
to become more prevalent due to drier
summers and wetter winters. At the
same time climatic stress on trees such
as oaks could also make them more
susceptible. Phytophthoras are linked to
Sudden Oak Death and "oak decline”.
Horse chestnut leaf miner
(Cameraria ohridella)
This moth causes severe damage to the
appearance of horse chestnut trees,
and benefits from hot dry conditions
when the tree is already suffering
drought stress. It is thought that climate
might also have a role to play in
increased incidence of bleeding canker
of horse chestnut, but this is currently
under investigation.
Appearance of exotic pest species
Exotic pests such as the southern pine
beetle could establish populations in
Europe, and climatic warming could
make UK forests susceptible to
damage.
Red band needle blight
This is an economically important
disease affecting a number of
coniferous trees, particularly pine
species. Since the late 1990s incidence
of the disease has increased
dramatically in Britain, particularly in
Corsican pine (Pinus nigra ssp. laricio).
Due to the extent and severity of the
disease on this species, there is now a
five-year ban on the planting of it on the
Forestry Commission estate. It is
thought that the increase could be due
in part to warm, wet springs in recent
years.
Increased global movement of timber
and wood products
The combined effects of increased
global movement of timber and wood
products, and climate change, are likely
to result in exotic pests such as Asian
longhorn beetle becoming more
prevalent.
Damage to Corsican pine caused by red
band needle blight
The impact of our changing climate on
pests and diseases means that we
must remain vigilant in reporting new
pests and altered patterns of damage.
When looking at the design and species
composition of our forests, we must
think about how pests and diseases
might affect the tree species that we
use and how this might change in the
future.
Exotic pests like this Asian longhorn beetle
might become more common. Park and
street trees are particularly at risk from this
species
Summary
• Climate change will affect our trees and woodlands and
we must help our forests to adapt.
• Many pests and diseases are likely to benefit from climate
change. We must continue to be vigilant in their
monitoring and think about changes that we might have
to make to the species composition of our forests.
The Forestry Commission is already
playing an important role in
combating climate change, and in
helping our forests adapt to the
changing climate
5 The role of the Forestry Commission
and climate change: a summary
The Forestry Commission is already playing an important role in mitigating climate
change and adapting to its impacts.
What is the Forestry Commission
doing about climate change?
1. Six point action plan
The Forestry Commission is tackling
climate change through the six point
action plan laid out in the Convenient
Truth (2007). Some of these actions are
directly relevant to our work in Forestry
Commission woodlands in England,
while others are achieved through
influencing the international forestry
and climate change agenda:
• Protecting and managing the forests
we already have
• Reducing deforestation
• Restoring woodland cover
• Using wood for energy
• Replacing other materials with wood
• Planning to adapt
2. Research
The Forestry Commission’s research
agency, Forest Research has carried out
climate change focused research for
many years. The significance of its role
in this area has now been further
recognised by the creation of a
dedicated Centre for Forestry and
Climate Change.
The Forestry Commission is sharing its
knowledge through the Global
Partnership on Forest Landscape
Restoration to help make a difference at
a global level.
Work has included:
• The development of the Ecological
Site Classification tool to assess the
likely impacts of climate change on
the suitability of individual tree
species and native woodland
communities
• Analysis of how climate change may
alter the impacts of pests and
diseases on trees and woodlands
• Investigating the ability of our native
species to adapt to climate change
4. Continuing to manage its forests
sustainably SHEET 7
3. Planting and promoting the
planting of more trees SHEET 6
There is also a global aspect to this
work. By planting new forests and
re-establishing those that have been
lost, we can help to restore the planet’s
forest cover.
5. Promoting and increasing the use
of wood products SHEET 8
6. Promoting and increasing the use
of wood as a fuel SHEET 9
7. Starting to adapt its woodlands to
climate change SHEET 10
8. Involvement in the development of
green infrastructure and research into
urban trees SHEET 11
Forests and forestry can be an
important and attractive part of
the solution
6 Mitigation: Planting more trees
Trees store carbon. One of the practical ways to combat climate change is to lock
up or sequester more carbon from the atmosphere through planting more trees as long as the right trees are planted in the right place.
Definition: The term mitigation refers
to activities aimed at reducing
greenhouse gas emissions and/or
removal of carbon dioxide from the
atmosphere.
A headline statistic is that the carbon
sequestered (or stored) by half a
hectare of conifer woodland over one
rotation can compensate for the carbon
dioxide emissions associated with car
fuel consumption during one average
driver's lifetime.
However, with 30 million registered
drivers in the UK, three quarters of the
land area of the nation would have to
be covered in forest to make car use
alone carbon-neutral. Therefore
planting more trees is an attractive part
of mitigating climate change, but can
clearly never be the whole solution.
Just how much carbon does one
tree store?
A recent study carried out at Kielder
Forest has calculated that the Forest’s
150 million trees lock up 82,000 tonnes
of carbon annually. This means that as
a rough estimate each tree at Kielder is
locking up 0.546kg of carbon per year –
equivalent to 2kg of carbon dioxide.
Although this example does answer the
apparently simple question ‘how much
carbon does one tree store,’ in reality
the answer is far from straight forward;
it is dependent on species, growing
conditions and how a tree is managed.
For example, 2500 trees might be
planted per hectare in a commercial
plantation (broadleaf or conifer) but only
50-500 remain when the final crop is
harvested as a result of natural
mortality and thinning.
Facts and figures
• UK forests and woodlands contain
around 150 million tonnes of
carbon
• UK forests and woodlands are a
carbon sink, as they remove about
4 million tonnes of carbon from the
atmosphere every year
• Current UK emissions of carbon
dioxide are about 550 million
tonnes per year
In addition, young trees absorb carbon
dioxide quickly while they are growing,
but as a tree ages a steady state is
eventually reached. At this point the
amount of carbon absorbed through
photosynthesis is equal to that lost
through respiration and decay.
It is, therefore, a much simpler concept
to talk about how much carbon an area
of woodland can sequester or store.
Fast growing conifer stands in the UK
can sequester about 10 tonnes of
carbon per hectare per year during their
active growth phase, although a more
typical figure representative of a
broader range of forest types is 3-5
tC/ha/yr. When UK woodlands are
looked at as a whole, the average falls
to 1-2 tC/ha/yr if removals during
harvest and the contribution from
unproductive woodlands are also
included.
In terms of total carbon storage, a
commercial conifer plantation grown
over 50 years might sequester 50-100
tonnes of carbon per hectare. In
contrast, an old growth forest may store
up to 250 tC/ha but over a much longer
period (300 years or more).
Carbon offsetting
Trees and forests have a clear role to
play in helping to mitigate climate
change, and tree planting projects
have been proposed as valid ways to
help ‘offset’ unavoidable carbon
emissions – carbon offsetting.
However, there has been resistance to
such projects for a number of reasons,
including the following:
• Is the activity ‘additional’ or would
the tree planting have occurred
anyway?
• Will the woodland be permanent, or
will the carbon be re-emitted in the
future?
• Will the carbon be counted only
once – or by a number of
individuals/organisations?
• Are the emissions reductions real?
The most important point is that
offsetting – whether through tree
planting or not – should not be the first
thought; reducing emissions should
always be the main objective.
Secondly, offsetting requires certainty
in the emissions reductions taking
place. This is a very difficult issue for
tree planting projects, which generally
provide funding for carbon uptake in
the future.
However, it is undeniable that planting
new woodlands in appropriate
locations removes carbon dioxide
from the atmosphere, and also
provides a number of other
environmental and social benefits that
many other offsetting options do not
provide. Tree planting projects
therefore do have a role to play in
helping to fight climate change, but
those investing in them need to be
aware of the issues involved.
Definitions:
Sequestration
This is the act of removing (literally
seizing) carbon dioxide from the
atmosphere and storing it in biological
material.
Sink
A forest is termed a carbon “sink” if
there is a net transfer of carbon from
the atmosphere to the forest. A forest
only remains a sink while its carbon
stock continues to increase.
Store
Wood products are a store of carbon,
as they themselves do not capture
carbon dioxide from the atmosphere,
but keep it locked up throughout their
lifetime.
Summary
• As long as the right trees are planted in the right place,
planting more trees can be an attractive way of removing
carbon dioxide from the atmosphere
• However overall, tree planting can only ever play a very
small part in climate change mitigation
Cutting down trees is not always bad
for the environment
7 Mitigation: Managing our woodlands
Sustainable woodland management practices balance the wide range of benefits
that woodlands provide, including biodiversity, recreation and effects on the
carbon cycle.
Sustainable forest management means
an ongoing cycle of trees growing and
being harvested for timber products. It
covers a range of approaches from
“energy forests” that are felled and
replanted over rotations as short as
seven years, to continuous cover stands
that are never clear-felled, but from
which timber trees are removed on a
regular basis and allowed to
regenerate naturally. However all
approaches are characterised by
maintenance of the amount of carbon
stored in the long term, and continued
growth.
Woods that are sustainably managed
generally have higher rates of carbon
storage (sequestration) than woodlands
that are not managed. This is because
when woodlands that are not managed
approach the “old growth” phase, the
amount of carbon dioxide that they
absorb from the atmosphere through
photosynthesis, is balanced by
emissions through respiration, litterfall
and decay. They may even start to emit
more carbon dioxide through
respiration and decay than they take in
through photosynthesis.
Woods where trees are periodically
thinned are generally also better for
associated woodland wildlife. More
light is able to reach the forest floor –
leading to an increase in diversity of
woodland flowers, insects and animals.
Careful management also helps to
protect woodlands against hazards
such as pests, diseases, storms and
fire.
Deforestation on the other hand implies
a change in land use to non-forested
land. In many parts of the world,
achieving a transition from
deforestation to forest conservation and
management is a challenge. The
But doesn’t cutting down trees
release more carbon dioxide to the
atmosphere?
In well-managed forests, felling trees
is part of the sustainable
management cycle. Felled trees are
replaced by young trees, by natural
seeding or coppice regrowth. Fastgrowing young trees absorb more
carbon dioxide from the atmosphere
than older trees. Trees that are felled
can be used to produce wood
products including wood fuel.
economic pressure for deforestation is
greatest in developing countries, but
every country in the world benefits from
maintaining forest resources where
trees are replanted when cut,
absorbing more carbon.
Protection through certification
The best way to ensure that timber
comes from a sustainable source is to
use an independently certified supplier,
or to ask suppliers whether they use
certified timber.
There are two global forest certification
schemes, which demonstrate that
timber and wood products come from
legal and sustainable sources. These
are:
FSC – Forest Stewardship Council
PEFC – Programme for Endorsement of
Forest Certification schemes
The FSC label is currently found on over
10,000 product lines in the UK alone –
from garden furniture, to bird boxes,
brushes, wallpaper, doors, toilet tissue,
paper books and pencils. FSC not only
certifies timber products; in fact all
forest products can potentially be
certified. Venison from Forestry
Commission land is one such non-
timber product that is FSC certified in the
UK.
In the UK, the UK Woodland Assurance
Standard is an independent certification
standard for verifying sustainable
woodland management. It
is not a certification scheme but is
designed to provide a single common
standard for use within those forest
certification programmes that operate
in the UK.
During 1999 every Forestry Commission
woodland in England, Scotland and
Wales (around 40% of British forests)
was assessed against the UK
Woodland Assurance Standard
(UKWAS) by an independent auditor. As
a result, Forestry Commission
woodlands now carry the Forest
Stewardship Council (FSC) stamp of
approval. This makes the Forestry
Commission the largest supplier of FSC
certified round timber in the UK.
Summary
• Wood products that come from well managed forests
have the most benefits in terms of combating climate
change, as more trees are planted in place of those cut
down
• Well managed woodlands generally store more carbon
than stands that are not harvested
• Buying wood from certified forests ensures that those
forests have been sustainably managed
• All Forestry Commission woodlands are now certified by
the Forest Stewardship Council
Wood is a smart choice
8 Mitigation: Using timber as a
renewable, low energy material
Wood products are unique. They come from a natural, renewable resource, which
can be sustainable if managed properly. The carbon they contain remains stored
for the duration of the product’s lifetime, until it decays or is burned. The longer the
wood product is used, the longer the period of time the carbon is stored.
A global increase in the use of industrial
wood products would help reduce the
amount of carbon dioxide in the
atmosphere, as long as the woodlands
from which they come are sustainably
managed.
When it comes to constructing homes
and buildings, wood has the lowest
energy consumption and carbon
footprint of any commonly used
building material.
Every cubic metre of wood that is used
as a substitute for other building
materials saves around 2 tonnes of
carbon dioxide:
• Around 0.9 tonnes of carbon dioxide
is stored as carbon in the wood
• On average 1.1 tonnes of carbon
dioxide are saved because of the
lower energy consumption involved in
manufacture
Use of wood in buildings also helps to
save energy over the life of that
building, as the cellular structure of
wood makes it an excellent thermal
insulator. It is:
• 15 times better than concrete
• 400 times better than steel
• 1770 times better than aluminium
0.2MJ
5.9MJ
6.3MJ
It isn’t just wooden housing that can help us
mitigate climate change – there are many
everyday products for which we can
substitute wood for other materials. This
picture gives an example of the differences
in carbon dioxide emissions for production of
a wooden, steel and a plastic spoon.
17g of CO2 emmissions
460g of CO2 emmissions
200g of CO2 emmissions
Wooden spoon
Stainless steel spoon
Plastic spoon
Wood products extend the period that
the carbon dioxide captured by trees is
kept out of the atmosphere. Increased
use of wood products can encourage
the expansion of forests, and as long as
they are well managed, more carbon
dioxide is captured from the
atmosphere through new growth.
The benefits of using more
wood products
• Wood stores carbon
• Wood products require less
energy to manufacture than
equivalent materials like steel
• Wood is a good thermal
insulator, saving energy and
money through running costs
• Wood is a beautiful material
• Wood is a long-lasting material
• Very little waste is generated
through the manufacture of
timber and wood products
• Any waste material can be burnt
as a fuel in place of fossil fuels
(see sheet 9)
• Using wood products can
encourage the expansion of
forests
Of course, not all products that are
currently made from plastics or concrete
can be made from wood. However,
using wood where possible and where
appropriate, can provide a valuable
and aesthetically beautiful part of the
solution to mitigating climate change.
Frequently asked questions
But what about the durability of
wood – buildings made of wood
won’t last very long will they?
Building with wood has a long history.
In Norway churches built from wood
in the 12th and 13th centuries are still
standing. In Japan there is even a
temple still standing which was built
in the 7th century.
But surely wood products can’t go
on storing carbon indefinitely?
Wood products increase the amount
of time for which carbon is stored. At
the end of its lifetime, it is likely that a
wood product will either: (a) decay, (b)
go into landfill, (c) be recycled e.g. to
produce chipboard or pulp for paper,
or (d) be burned.
Today the average service life of a
wooden house is between 80-100
years, with some builders
guaranteeing a lifetime of 125 years.
This is where it is important that the
wood used in building and in
products, comes from a sustainably
managed woodland, so that more
trees are planted, which can absorb
carbon dioxide, to replace those that
have been harvested to create the
wood product.
Doesn’t using wood in buildings
create a fire hazard?
The technology for timber frame
buildings has been developed
extensively over the last ten years.
New fire retardant treatments that last
for the life of the building make
modern timber buildings fire-safe.
Trees
harvested
and wood
products
created
Trees
absorb
carbon
dioxide
If a wood product is burned for fuel at
the end of its lifetime, then it reduces
the need to burn fossil fuels.
Carbon
dioxide stored
as carbon in
wood
products
More trees
planted
At end of
lifetime
Burnt as
a fuel
Recycled as
chipboard or
paper pulp
Decompose
in landfill
Carbon
dioxide
released
Summary
• Wood products store carbon for the duration of their
lifetime.
• As long as the trees come from a well-managed forest,
new growth absorbs more carbon dioxide from the
atmosphere.
• Less energy and thus less fossil fuels are required in wood
product manufacture than equivalent materials.
• Not all products can be made from wood, but a global
increase in wood products would help to decrease the
amount of carbon dioxide in the atmosphere.
Wood is a smart choice
9 Mitigation: Wood fuel – renewable
energy that grows on trees
Wood used for energy is wood fuel. When used in place of fossil fuels, wood fuel
reduces the net amount of carbon dioxide released to the atmosphere. There is
the potential for the expansion of wood fuel use in the UK, but it is essential that
forests that supply wood are managed sustainably.
Wood fuel is a well-established form of
heating, probably the oldest used by
humans. Modern wood fuel systems
burn the wood cleanly and efficiently
and offer convenience and comfort.
Although burning wood releases
carbon dioxide, this is balanced by the
carbon dioxide absorbed by the growth
of new trees planted in place of those
cut down. It is a carbon lean rather than
a carbon neutral fuel, as small amounts
of fossil fuel are required for its
production and transportation.
Fossil fuels locked up carbon millions
of years ago in a very slow process.
When fossil fuels are burned, the
carbon is released very quickly. It
takes millions of years for new coal
and oil to form.
Coppicing
Coppicing is one type of traditional
sustainable woodland management
which is often used to produce wood
fuel.
Coppicing involves cutting the stems
from a tree to leave a stump or “stool”
which regrows. Each section of
woodland will be cut about once
every 15-30 years depending on the
species being grown. Willow and
poplar are also grown as short
rotation energy crops over cycles as
short as 3 years.
A never-ending harvest
Trees absorb
carbon dioxide from
the atmosphere
Trees are harvested
and burnt as wood
fuel
More trees
planted
Small amount of
CO2 released in
transport and
processing
Carbon dioxide
released from
burning of the fuel
This diagram shows that if more trees are planted in place of those cut down, wood can be a
carbon lean fuel.
Heat is the biggest energy demand
in the UK – more than both
electricity and transport. Therefore
this is the best use of wood for
energy in terms of carbon savings.
Fuel
Approx life cycle
CO2 emissions kg/MWh
Coal
484
Oil
350
Natural gas
270
Large scale wood chip combustion
58
Frequently asked questions
Large scale wood chip gassification
25
Wood chips (25% moisture content)
5.5-6.6
Wood pellets (10% moisture content)
20
Can wood fuel solve all of the UK’s
energy requirements?
There are simply not enough trees
in the UK to provide enough energy
through wood fuel for all our
requirements. However wood fuel
can provide a good, positive part of
the solution to reducing carbon
emissions in conjunction with other
renewable technologies.
These figures show emissions over the life cycle of the fuel. This means that they include
supply chains, production techniques and transport distances. In the case of wood fuel,
emissions during combustion are assumed to be compensated for by the future growth of
trees managed on a sustainable basis. Figures from the Biomass Energy Centre.
Benefits of wood fuel
• Wood fuel is a carbon-lean fuel (see
above)
• Producing and using wood fuel
locally helps to minimise use of fuel
in transport
• Greater self-sufficiency for local
communities
• UK produced wood fuel contributes
to fuel security
• Creates new business opportunities
– stimulating the rural economy and
providing employment
There is potential to increase the use of
wood fuel in England as 60% of our
forests are currently thought to be
undermanaged. The Forestry
Commission’s Wood Fuel Strategy for
England aims to bring an additional two
million tonnes of wood into the market
annually by 2020. This could supply
250,000 homes with energy, equivalent
to saving 3.6 million barrels of crude oil.
Providing woodland owners with
practical advice and skills to make
informed choices about managing their
woodland to produce wood fuel is one
• Creating a market for wood fuel
helps to bring woodlands into
management
• Sensitively managed woodlands
generally provide better habitats for
a wider range of woodland plants,
birds, animals and insects than
unmanaged woodlands
• Wood fuel can save you money – it
is often a cheaper option and has a
more stable price than fossil fuels
of the key tasks for Forestry Commission
England – especially for those new
woodland owners with no background
in land management.
However, none of the benefits of wood
fuel will be realised unless woodland
management is profitable. Wood fuel
can be made from the lowest grade
wood – providing a market for the
poorest quality parts of the tree, while
the higher quality timber can be used to
make wood products, which lock up
carbon for a long time.
Isn’t wood a dirty fuel?
Wood fuel systems produce very
little ash, typically less than 1% and
often much less. Wood fuel boilers
typically run at very high efficiencies
– up to 90% with some systems.
This means that the fuel is
converted to heat with very few
smoke particles. The most
important thing is to ensure that the
boiler is well designed and well
maintained.
Isn’t it expensive to install a wood
fuel system?
Although they are more expensive
to buy than other boiler systems,
running a wood fuel boiler is
comparable to or cheaper than an
oil boiler. There are also grants and
other financial support available for
those wishing to install renewable
energy systems. Wood fuel works
best on a local scale – using locally
grown trees in efficient boilers to
provide heat for business and
community use reduces haulage
costs and carbon dioxide
emissions.
Summary
• Trees absorb carbon dioxide from the atmosphere. This is
released back to the atmosphere when the wood is
burned. More carbon dioxide is then absorbed by trees
planted in their place.
• To reap the carbon benefits, woodlands producing wood
for fuel must be managed sustainably: trees must be
replanted if cut down.
• Wood fuel is carbon lean, rather than carbon neutral as
some carbon dioxide emissions are produced during
transport and processing.
• Modern wood fuel systems burn wood cleanly and
efficiently with little smoke or ash.
• Wood fuel is a positive part of the solution to reducing
carbon emissions.
Our forests are changing due to
climate change and we need to plan
ahead to help them adapt
10 Adaptation: helping our forests
adapt to climate change
Adaptation to climate change means changing the way that we do things to take
account of the inevitable and unavoidable changes that have started and will
continue to happen during the coming decades.
In terms of forestry this means
designing and managing forests and
woodlands so that they are able to
cope with, and help society to cope
with, climate change. We must ensure
that our commercial woodlands are
economically viable by helping them to
adapt. In doing this we must make sure
that our semi-natural woodlands are
not compromised, and that our actions
do not introduce threats for the future.
Woodlands can also contribute to flood
prevention, help to cool our cities and
create wildlife corridors (covered by
sheet 11).
Due to the large size and long life span
of trees, forest ecosystems are likely to
be slow to react to changing climatic
conditions, and for this reason we must
think ahead in planning how to adapt
our forests to climate change.
How can we help our woodlands
adapt to climate change?
1. Species and provenance choice
Forest managers have to consider
whether their woodlands will survive in
a future climate. Forest Research are
currently carrying out a number of
species trials across the country to look
at which species or provenances might
be better suited to the climate of the
future.
The difficulty lies in ensuring that
decisions made now are appropriate to
both the current and future climate, and
cover the considerable uncertainty over
what the future climate will be.
Ensuring that a forest is diverse, in
terms of age structure, species and
origin, will help to provide it with the
resilience to cope with changing
conditions.
What does provenance mean?
This is the site or locality from where
the planting material was sourced.
For example oak of French
provenance might be better suited to
a warmer climate than oak of local
provenance in southern England.
See Case Studies 1 and 2 (Sheets 14 and
15) for more information on how the
Forestry Commission is planning ahead.
2. Ecological Site Classification (ESC)
ESC is a computer based system to help
guide forest managers and planners to
identify how species being considered
for woodland creation or restocking
may respond to climate change.
Focus on… beech
Currently beech (Fagus sylvatica L.) is
very common in its native southern
range, but as these ESC maps show,
the abundance and vitality of the
species is likely to decline over time,
particularly in southeast England.
Shallow-rooted species like beech are
vulnerable to an increase in extreme
weather events, and lower moisture
levels due to drier, warmer summers.
This can cause die-back and species
that are more drought-tolerant may be
able to invade. This means that in
areas of southern England, beech may
no longer be suitable as a timber crop.
This does not mean that beech will
disappear from the landscape, but
planting a wider range of species on
sites where beech is predicted to
suffer would be prudent.
Very suitable
1961-90
2050s high
2080s high
Suitable
Marginal
Unsuitable
Potential decline in suitability of different areas of the UK for beech with projected climate changes. High refers to high emissions scenarios.
Plant and animal communities have
evolved in response to climatic
conditions since the last ice age.
Within the range of climatic
fluctuation species have moved to
occupy suitable environments.
However greater extremes and fast
changing climatic regimes will mean
that species are subject to greater
variation.
3. New natives?
Current UK policy encourages the
planting of local provenances of native
species, because these are likely to be
adapted to local conditions. However
these species and provenances may
not be able to adapt to a fast-changing
climate. It may be necessary to re-think
the importance of always choosing
native species. Another solution may be
to source plant stock of native species
from more southerly regions, which
experience a current climate similar to
that predicted for our future.
4. Management of existing woodland
Increased productivity because of
higher temperatures and carbon
dioxide levels mean that rotation length
(the length of time it takes for a tree to
be ready for felling to produce timber
products) and the timing of thinning
may need adjustment. Management
may also need to take into account
changes in storm frequency, the effects
of winter waterlogging on access for
management, or the timing of the
planting window.
5. Pests and diseases
It is essential to remain vigilant in
reporting new pests and diseases and
altered patterns of damage. It is also
necessary to think about changes in
species choice in relation to potential
pest and disease problems, as is
shown by the current moratorium on
planting of Corsican pine on the Forestry
Commission estate. (See sheet 4 for
more information on pests and
diseases).
6. Reducing other pressures
By removing or reducing other
pressures on woodlands, such as
invasive species and pollution, we can
help to increase the resilience of our
woodlands.
7. Landscape design
Making our existing semi-natural
woodlands larger provides a buffer to
environmental change – increasing their
resilience. New woodlands can help to
create habitat networks and linkages so
that species are able to move more
easily across the landscape in response
to climate change.
8. Monitoring and evaluation
There is a great deal of uncertainty
involved in predicting the exact effects
of climate change. It is essential that we
closely monitor the results of the actions
that we take to help identify adaptation
strategies for the future.
Summary
• Forest ecosystems are likely to be slow to react to climate
change and we must plan ahead to help them adapt.
• The Forestry Commission is carrying out research into
which species might be best adapted to our future climate.
• It may be necessary to consider whether non-native
species have a role to play in our woodlands of the future.
• Another solution could be to plant more southerly
provenances of our native species.
• Good conventional management practice will make our
woodlands more resilient to climate change.
Trees can help us to adapt to a
changing climate. They provide
shade, alleviate flooding, and create
a valuable wildlife habitat
11 Adaptation: How our woodlands
can help society to adapt to a
changing climate
Appropriately located woodland can help society and biodiversity to adapt to the
impacts of climate change. Trees planted in the right places can reduce the risk of
flooding, provide shade for our wildlife, reduce soil erosion and help to cool down
our towns and cities.
Trees in the urban environment
The urban heat island effect means that
temperatures in our towns and cities
tend to be around 2°C higher than in
rural areas. The built environment is
also designed to increase runoff which
means that water supply to these trees
is often limited. Therefore it could be
said that trees in urban areas are
already adapted to the type of climate
change that we can expect to see in the
UK over coming decades.
An urban heat island is a built up
area which is significantly warmer
than surrounding rural areas. The
main cause is modification of the
land surface by urban development.
Trees and woodland are a vital
component of what has become known
as "Green Infrastructure" - a network of
interconnected and multipurpose green
areas.
It is important to think about whether
the species currently used as street
trees will be suited to our future climate.
Potential benefits from expansion of urban trees and woodland:
• Trees absorb and reduce air
pollutants, which are often highest
in urban areas.
• Trees reduce the impact of heavy
rains and floodwaters. This will
become increasingly important with
the increase in severe weather
events predicted with climate
change. It also means that trees
can have an important role in
Sustainable Urban Drainage
Systems (SUDS).
• Trees help to cool towns and cities
through evaporation of water,
reflection of sunlight and provision
of shade.
• Planting trees and woods in urban
areas creates urban wildlife
corridors. This can help species
movement in response to climate
change.
Flood alleviation
As well as reducing the risk of flooding
in urban areas, woodland in headwater
catchments can reduce the intensity
and volume of floodwaters. Floodplain
woodland lower in the catchment can
provide floodwater storage and reduce
peak flows.
Riparian woodland
Trees planted along riverbanks can also
provide shade, helping to maintain
lower water temperatures. This can
help limit the effects of climate change
on fish populations.
Pony sheltering under trees in the New
Forest
Soil erosion control
Tree canopies reduce rainfall intensity,
act as a windbreak, and stabilise soil,
reducing erosion. By reducing soil
erosion trees also help to reduce
consequent diffuse water pollution and
the flooding that results from water
courses silting up.
Summary
• Trees can help society and biodiversity to adapt to climate
change: yet another reason to make sure that our
woodlands are resilient to climate change
• Trees in urban areas have an important role to play in
reducing the urban heat island effect
• Trees and woodlands can help to reduce the impact of
floodwaters by reducing their volume and intensity
12 What can individuals do?
Wood products
Where possible buy wood products in
place of other materials such as
plastics. In order to ensure that these
are from sustainably managed forests,
make sure that they are certified. FSC
is the most common logo to look for on
consumables in this country.
The FSC logo now appears on a huge
range of products, from garden
furniture to decking, sheds,
conservatories, tools, bird boxes and
bird tables, kitchen, bathroom and
general housewares, brushes,
wallpaper, flooring, doors, shelves,
furniture, toilet tissue, paper, books
and pencils – most things that are
made from wood. It can also be found
on other forest products such as
venison, essential oils, and latex for
footballs and balloons.
Timber in building
Consider timber as a building material
if undertaking building projects.
Individuals could also consider using
wooden frames when replacing
windows, or wooden flooring in the
home. Ensure that these are certified either by FSC or other certification
schemes. Even asking suppliers if they
use certified timber can have an impact
on their buying patterns.
Wood as a fuel
Can you think about switching to a
wood burner to heat your home?
Could you encourage your business or
community buildings to switch to using
an efficient wood fuel boiler to provide
heat and hot water?
As well as the carbon saving and
environmental benefits, this could save
you or your business money
particularly if you currently use heating
oil. Most importantly seek good advice
on size, design and fuel.
Charcoal
In Britain we import 95% of our
charcoal each year – a large proportion
of which comes from unsustainable
sources such as tropical forests or
cleared mangrove swamps. Look out
for FSC or other certified charcoal to
make sure that it is from a sustainable
resource. Even better, buy locally
produced charcoal to support local
woodlands and reduce the distances
that the charcoal is transported.
Paper
If possible choose recycled paper as
this is the greenest option overall – it
prevents waste paper going to landfill,
and requires fewer chemicals and
about 70% less energy and 40% less
water in its production. Where it is not
possible to buy recycled paper, use
paper which is certified, e.g. by FSC.
There will always be the need for some
virgin fibre (from newly cut down trees)
as recycled fibres can only be
reprocessed 6-8 times – in these cases
it is important to use fibres from
certified forests.
Christmas trees
Buy real. As long as your real
Christmas tree comes from a well
managed woodland it can offer a more
climate-friendly alternative to a fake
tree. Reports show that using a fake
tree results in greater carbon dioxide
emissions than using a new real tree
Volunteer
Where opportunities exist, get involved
in helping to manage your local
woodland!
each year, if the fake tree is used for
less than 20 years. All FC Christmas
trees are sustainably grown in the UK
in plantations that are replanted after
they are felled. Make sure you recycle
your real Christmas tree after you have
finished with it!
The Forestry Commission is already
playing an important role in
combating climate change, and
in helping our forests adapt to
climate change
13 Case Studies
The following case studies seek to provide some practical examples of what the
Forestry Commission is already doing to try to combat and adapt to climate
change. This is not an exhaustive list, but can be added to at any time.
Case Study 1:
Adaptation: National Arboreta Long Term Planning Group
Case Study 2:
Adaptation and long term planning: Jeskyns
Case Study 3:
Mitigation (wood fuel) and Adaptation (research): Bedgebury
Case Study 4:
Mitigation - using more wood in building: Cannock, Dalby and Westonbirt
Without planning ahead and beginning to think about irrigation,
Japanese maples may find it hard to cope with summer drought. Can
you imagine Acer Glade at Westonbirt Arboretum without any acers?
14 Case Study 1: Planning for the future
Adaptation - the National Arboreta Long-term Planning Group
representatives from Westonbirt
Arboretum, Bedgebury Pinetum and
Forest Research, and has been set up in
order to plan and react to these
changes in our climate, and consider
how they may affect the future
composition and management of the
collections. Although these changes are
predicted to take place over the next 50
–100 years, now is the time to make
plans for any necessary shifts in tree
species composition.
The National Arboreta - Westonbirt and
Bedgebury - are two world renowned
Forestry Commission tree collections.
They are both located in southern
Britain, the region predicted to
experience the greatest changes in
terms of milder but wetter winters and
warmer, drier summers, with climate
change.
The National Arboreta Long-term
Planning Group includes
The group is preparing a climate
change risk assessment for the
Arboreta and is in the process of
creating and implementing an
adaptation action plan to address these
risks. This involves looking at the content
of the collections, including species mix
and vulnerability or resilience to
change, and assessing the risks facing
the collections in terms of pests and
diseases.
As well as nationally important
collections at Westonbirt and
Bedgebury, the Forestry Commission
has at least 20 other tree collections
across Britain. These sites can be used
as valuable repositories for species that
might no longer be suited to arboreta in
other parts of the country or the world.
The National Arboreta also have an
important role in communicating the
impacts of climate change on trees. Part
of the role of the Planning Group is to
raise awareness about the need to preempt and respond to projected climate
change and its associated effects.
15 Case Study 2: Planning for the future
Adaptation at Jeskyns
Forestry Commission England has set
up a project at Jeskyns in Kent that
demonstrates one approach to
ensuring that new woodlands are
resilient to climate change. The
demonstration woodland is divided into
a “Woodland of the Present” and a
“Woodland of the Future”.
The “Woodland of the Future” contains
some species that are likely to be more
resilient to hotter and drier climates.
Some of these species, including smallleaved lime and hornbeam, are native
to the British Isles, but some non-native
species have also been included. The
seeds of native species used to grow
the trees in the “Woodland of the
Future” have been collected from
warmer areas of Europe.
Aims of this project:
• To create a diverse woodland, which
is resilient and able to adapt to
projected climate change, and which
can be monitored to help plan
woodlands elsewhere.
• To demonstrate that adapting to
climate change does not mean
wholesale changes and that
hopefully, we can retain our
characteristic wooded landscape
through subtle changes.
• To engage people in the work needed
to tackle the impacts of climate
change, and show that it is both
necessary and possible to adapt. An
interpretation board is currently in
production, which will help to meet
this aim.
The plot at Jeskyns will be monitored by
Forest Research to identify the strengths
and weaknesses of the various species.
The results will help to inform plans for
planting new trees and woodlands
across the public forest estate in
England.
There are several Forestry Commission
research plots of this nature planted
across the UK. Forestry Commission
Wales is using one such plot as part of
a new education programme to
engage secondary school students in
the importance of planning for the
future in terms of species choices and
species mixes. After visiting the plot,
students work towards designing what
they think a forest of the future will look
like.
16 Case Study 3: Mitigation and
adaptation at Bedgebury
Scientists from Forest Research are
exploring how temperature and other
climatic changes are affecting the tree
species that are able to grow at
Bedgebury. Attempts are being made
-5
-10
Mar
Feb
Jan
-15
Dec
Studying temperature
variation at Bedgebury
0
Nov
This is one of 10 wood fuel heating
systems used at Forestry Commission
sites designed to reduce carbon
emissions and dependence on fossil
fuels. The woodchip boiler also helps to
combat climate change by using wood
waste from the site to fuel the boiler –
thus reducing transport miles.
in order to extend the range of species
that Bedgebury can conserve. This
detailed monitoring will also
demonstrate how adaptation to climate
change can be achieved simply by
using topography and aspect within a
site.
5
Oct
In 2006 a new woodchip boiler was
installed at Bedgebury, the national
pinetum. Home-grown coppiced
chestnut from Bedgebury forest is
chipped and used as fuel for the new
boiler which provides heating and hot
water for the Visitor Centre.
to grow trees from warmer regions that
were unable to grow at Bedgebury 50
or even 10 years ago. Monitoring these
trials helps to assess the impacts of
climate change. Scientists are also
looking at temperature variation within
the pinetum to identify where to plant
the most temperature sensitive species,
Minimum temperature (oC)
Wood fuel at Bedgebury
Minimum monthly temperature in each section of Bedgebury Pinetum during
October-March 2005
Graph showing temperature variation across site at Bedgebury. Each line shows the minimum
monthly temperature of a different section of the pinetum. This demonstrates that we can
adapt to climate change by simply choosing carefully where in a particular site to plant
different species.
Picture of Cannock Tree House Centre
17 Case Study 4: Mitigation –
Using more wood in building
Wooden buildings at Cannock, Dalby and Westonbirt
Cannock Chase
A brand new education building, the
“Tree House Centre” was opened in
Cannock Forest in 2008 funded by
CEMEX. The building has two large
classrooms, each of which can
accommodate up to 60 students,
covering 347m2 in total.
The building is constructed entirely from
FSC timber and supported by 64 oak
posts, reducing the ground impact and
the amount of concrete used. The
building has a living sedum roof, and a
rainwater harvesting system that
collects water from the roof and uses it
for toilet flushing, saving on mains
water use.
The building is heated by a wood pellet
system and has a large overhanging
roof structure to reduce overheating in
summer. In addition because the
building is constructed from wood, it is
very well insulated–helping it to stay
warm in winter and cool in summer.
Passive solar heating is also achieved
by extensive south facing windows.
Dalby
April 2007 saw the opening of a stateof-the-art visitor centre at Dalby Forest
in the heart of the North York Moors.
The striking £2.6m building has been
constructed from natural materials and
nestles into the wooded valley. It
enhances the distinct character of the
forest.
The construction of the all-timber
building uses new techniques that
enhance quality while lessening the
impact on the surrounding area. It is
clad in locally-sourced timber shingles
made from Yorkshire larch. Being made
of wood, the building is naturally wellinsulated. It is powered by energy from
photo-voltaic panels and a wind
turbine. Heating is provided by a
biomass boiler.
Westonbirt
The new craft barn at Westonbirt was
built during a training course in
traditional woodworking techniques
and raised in one day in October 2008.
The barn demonstrates the use of
timber from our native woodlands and
provides a shelter for courses and
demonstrations in green woodworking.
All the timber for the barn was
harvested from the arboretum,
including the oak and chestnut shingles
for the roof. The oak for the frame itself
came from mature woodland trees
felled during Westonbirt’s programme
of coppice restoration. The natural
durability of oak means that the barn
should be around for at least 500 years
– long after a new generation of oaks
have grown and been harvested to
make another one!
18 Summary of Facts and Figures
Worldwide
Forests cover 30% of the world land
area.
Globally forests store nearly 1200 billion
tonnes of carbon: 350 billion tonnes in
vegetation (including the roots) and 800
billion tonnes below ground in the soil.
This is more than the total amount of
carbon in the form of carbon dioxide in
the atmosphere (750 billion tonnes of
carbon).
Since the industrial revolution
atmospheric concentrations of carbon
dioxide have risen by 40%, and 270
billion tonnes of carbon have been
released into the atmosphere as carbon
dioxide
Worldwide 23 billion tonnes of carbon
dioxide are added to the atmosphere
annually through the burning of fossil
fuels, and 6 billion tonnes are added
from deforestation. Some of this is
absorbed by the oceans and by
vegetation, resulting in a net gain by the
atmosphere of nearly 12 billion tonnes
of carbon dioxide per year.
Deforestation currently accounts for 18%
of global carbon dioxide emissions
We can now expect a rise in
temperature of 2°C above pre-industrial
levels by 2100 even if we decrease our
carbon dioxide emissions dramatically.
If no action is taken, the rise in
temperature could be as large as 7°C
Europe
Europe’s forests have increased in
extent in the last century. They now
cover 44% of the land area.
The amount of carbon in European
wood products is 769 billion tonnes
Europe’s forests contain about 20 billion
tonnes of carbon, equivalent to 74
billion tonnes of carbon dioxide.
Soil is the largest carbon reservoir in the
UK, storing about 6 billion tonnes of
carbon.
UK forests and woodlands remove
about 4 million tonnes of carbon
(equivalent to 14.8 million tonnes of
carbon dioxide) from the atmosphere
each year.
Total UK emissions of carbon dioxide
are about 550 million tonnes per year
Carbon dioxide contributed to over 85%
of total greenhouse gas emissions in
2004 in the UK
Nearly a third of energy consumption in
the UK is used to heat buildings.
In the UK
Analysis of historic climate data
confirms that the UK climate has
recently been warming at a rate of
between 0.1°C and 0.2°C per decade.
Forests cover 12% of the land area in
Britain, up from 5% at the beginning of
the 20th Century.
Winters in the UK are likely to become
wetter (by up to 30%) and summers
drier.
UK forests and woodlands contain
between 120-150 million tonnes of
carbon.
It is thought that there will be a sea level
rise of between 1-10cm around the UK
coast per decade over the next 100
years. Relative sea level will increase
most in the south and east (where the
land is already sinking) and increase by
less in the north and west.
The volume of wood supplied from
Britain’s forests each year has more
than doubled from 4 million cubic
metres in the 1970s to nearly 9 million
now. There is the potential to increase
this to 15 million cubic metres by 2020.
The thermal insulation of wood is:
15 times better than concrete
400 times better than steel
1770 times better than aluminium
Research into the environmental
impacts of building construction
suggests that increasing the use of
wood in place of other materials could
cut greenhouse gas emissions by
between 40% and 70% per building
Wood fuel is a carbon lean source of
energy. The Wood Fuel Strategy for
England aims to bring an additional two
million tonnes of wood onto the market
annually by 2050.
Fuel
Approx life cycle
CO2 emissions kg/MWh
Coal
484
Around 85% of the wood products
currently used in Britain are imported.
Oil
350
Natural gas
270
In the UK 95% of our charcoal is
imported.
Large scale wood chip combustion
58
Large scale wood chip gassification
25
Wood chips (25% moisture content)
5.5-6.6
Wood pellets (10% moisture content)
20
In 2008, 43,119 real Christmas trees
were sold at Forestry Commission sites
in England – all from well managed
woodland. In 2008 8,145 young
Christmas trees were given away at
Forestry Commission England’s santa’s
grottoes.
Wood
One tonne of carbon is equivalent to 3.7
tonnes of carbon dioxide
Each cubic metre of wood used in
building instead of conventional
materials saves about 2 tonnes of
carbon dioxide: one tonne of carbon
dioxide is stored as carbon in the wood,
and one tonne of carbon dioxide is
saved in manufacture
Growing trees absorb carbon dioxide
from the atmosphere on average at a
rate of one tonne for every cubic metre
of growth. However this varies
depending on species, age and where
in the world the trees are planted.
Comparison of carbon dioxide emissions of different fuels over their life cycle
The life cycle includes production, management and transport. In relation to wood fuels,
emissions during combustion are assumed to be compensated for by the future growth of
trees managed on a sustainable basis.
19 References and further information
The Forestry Commission (www.forestry.gov.uk/climatechange) and Forest Research
(www.forestresearch.gov.uk/climatechange) climate change web pages are a good starting point for
finding out more information. Below are details of where the information for each topic came from,
and some suggestions for finding out more.
Sheet 2: Background
Broadmeadow, M. & Matthews, R.
(2003) Forests, carbon and climate
change: the UK contribution. Forestry
Commission Information Note 48.
www.forestry.gov.uk/publications.
The Strategy for England’s Trees, Woods
and Forests (ETWF) and the ETWF
Delivery Plan 2008-2012 can be found
at www.forestry.gov.uk/etwf
Forestry Commission England (2008)
Leafing the Classroom: Strategy for
Forestry Commission Estate Education
and Learning Services 2008-2012.
Forestry Commission (2007). Forests
and Climate Change: A Convenient
Truth. This can be downloaded from
www.forestry.gov.uk.
Sheet 3: What will climate change
look like?
Hulme (2002) The changing climate of
the UK: now and in the future. In
Broadmeadow, M. ed. Climate change:
Impacts on UK forests. Forestry
Commission Bulletin 125.
Jenkins, G.J., Perry, M.C., & Prior, M.J.
(2008). The climate of the United
Kingdom and recent trends. Met Office
Hadley Centre, Exeter, UK.
www.ukcip.org.uk.
The UK Climate Impacts Programme
(UKCIP) publish revised future climate
scenarios every six years. See the latest
scenarios on the UKCIP website:
www.ukcip.org.uk.
For more details on the science of
climate change see the IPCC Fourth
Assessment Report: www.ipcc.ch.
Sheet 4: Implications for forestry
Information on general impacts
came from Broadmeadow and
Matthews (2003) below. The reports
listed here can be found on the Forestry
Commission Publications website:
www.forestry.gov.uk/publications.
Sheet 5: Summary of the Forestry
Commission role
An information booklet entitled “Forest
Research Climate Change Projects” can
be downloaded from
www.forestresearch.gov.uk/
climatechange.
Broadmeadow, M. & Matthews, R.
(2003) Forests, carbon and climate
change: the UK contribution. Forestry
Commission Information Note 48.
Benham, S. (2008) The Environmental
Change Network at Alice Holt Research
Forest. Forestry Commission Research
Note 001.
www.forestry.gov.uk/publications.
Broadmeadow, M. & Ray, D. (2005)
Climate change and British woodland.
Forestry Commission Information Note
69.
Ray, D. (2008) Impacts of climate
change on forestry in Wales. Forestry
Commission Research Note 301.
Ray, D. (2008) Impacts of climate
change on forestry in Scotland – a
synopsis of spatial modelling research.
Forestry Commission Research Note 101.
Information on pests and diseases
came from the Forestry Commission
and Forest Research websites, and
from: Evans, H., Straw, N. and Watt, A.
(2002) Climate change: Implications for
insect pests. In Broadmeadow, M. ed.
Climate change: Impacts on UK forests.
Forestry Commission Bulletin 125.
Brown, A. & Webber, J. (2008) Red band
needle blight of conifers in Britain.
Forestry Commission Research Note
002.
Brasier, C. (1999) Phytophthora
pathogens of trees: their rising profile in
Europe. Forestry Commission
Information Note 30.
www.forestresearch.gov.uk.
Broadmeadow, M. & Ray, D. (2005)
Climate change and British woodland.
Forestry Commission Information Note
69. www.forestry.gov.uk/publications.
Sheet 6: Mitigation – planting more
trees
Information on the carbon budget of
Kielder Forest came from: Grieg, S.
(2008) A Carbon Account for Kielder
Forest. Scottish Forestry 62(3).
Sheet 7: Sustainable management
and protection
Information about sustainable
management came from the Forestry
Commission and Forest Research
websites, as well as the BTCV website
(www.btcv.org), which has a very good
online guide to woodland
management. Information on
certification came from the Forestry
Commission website and the Forest
Stewardship Council website:
www.fsc.org.
Sheet 8: Mitigation - wood products
The Wood for Good website is an
excellent starting point for finding out
more information about wood as a
material and as a product. Wood for
Good is the UK’s wood promotion
campaign, and the Forestry
Commission is one of the three main
sponsors. Go to:
www.woodforgood.com. Much of the
information for this section came from
the Wood for Good factsheets available
on the website.
Wood for Good are also involved in a
pan-European project to communicate
the role of wood products in mitigating
climate change, and have produced a
booklet with the Nordic Timber Council
entitled “The role of wood in reducing
climate change: a summary of the
arguments”. Type this title into Google to
download.
Also interesting is: Journal of Forestry
(2008) Chapter 3: Preventing
greenhouse gas emissions through
wood substitution. Type this title into
Google to download.
Sheet 9: Mititation - wood fuel
The wood fuel pages of the Forestry
Commission website
(www.forestry.gov.uk/woodfuel) are a
good general reference, and include “A
Wood Fuel Strategy for England”. The
Biomass Energy Centre website:
www.biomassenergycentre.org.uk is
also a very good reference point.
The Forestry Commission England has
produced a DVD called “Wood fuel:
Energy that grows on trees” which can
be downloaded from:
http://www.forestry.gov.uk/forestry/
infd-7fzdbd.
Forest Research have produced a
“Wood Fuel Information Pack” which can
be ordered from
www.forestresearch.gov.uk/woodfuel.
A useful leaflet is “Wood Fuel Meets the
Challenge” (2006) – a Forest Research
publication by Duncan Ireland, Jenny
Claridge and Richard Pow. This can also
be downloaded from
www.forestresearch.gov.uk/woodfuel.
Farming Futures Fact Sheet 19: Climate
change: be part of the solution – focus
on biomass for renewable energy.
Download from:
www.farmingfutures.org.uk.
Sheets 10 and 11: Adaptation
Information came from the Forestry
Commission and Forest Research
websites, and from Broadmeadow and
Ray (2005) Climate change and British
woodland. Forestry Commission
Information Note 69.
www.forestry.gov.uk/publications
Broadmeadow, M. & Ray, D. (2005)
Climate change and British woodland.
Forestry Commission Information Note
69.
Hubert, J. & Cottrell, J. (2007) The role of
forest genetic resources in helping
British forests respond to climate
change. Forestry Commission
Information Note 086. This report
explains the science behind species
choice and looks at some of the
questions surrounding native species
and climate change.
www.forestry.gov.uk/publications.
Defra (2008) Adapting to climate
change in England: A framework for
action. www.defra.gov.uk.
RSPB (2008) Climate Change: Wildlife
and Adaptation – 20 tough questions,
20 rough answers. www.rspb.org.uk.
Sheet 17: Facts and Figures
Facts on climate change in the UK came
from Hulme (2002) (see sheet 3
references on previous page).
Figures on wood product manufacture
and insulative values came from
www.woodforgood.com.
Statistics on global carbon budgets are
from the Forestry Commission website,
and “Forests and Climate Change: A
Convenient Truth” which can be
downloaded from www.forestry.gov.uk.
Facts on wood fuel came from “Wood
Fuel Meets the Challenge” and the
“Wood Fuel Information Pack” see
references for sheet 9). The table of
relative carbon dioxide emissions is
from the Biomass Energy Centre
website:
www.biomassenergycentre.org.uk.
20 Definitions
Greenhouse gas
Any gas in the atmosphere that absorbs
and emits radiation within the thermal
infrared range. This process is the
fundamental cause of the greenhouse
effect. Greenhouse gases occur
naturally within the Earth’s atmosphere,
and the Earth would be uninhabitable
without them. Common greenhouse
gases in the Earth’s atmosphere include
water vapour, carbon dioxide, methane,
nitrous oxide and ozone.
Adaptation
Adaptation to climate change means
changing the way that we do things to
take account of the inevitable and
unavoidable changes that have started
and will continue to happen during the
coming decades.
Carbon footprint
This term provides a measure of the
impact certain activities have on the
environment in terms of the amount of
greenhouse gases produced.
Carbon neutral/carbon lean
Wood fuel is often described as carbonneutral because the carbon dioxide that
is produced by burning wood is
absorbed by trees planted in place of
those cut down. However, in reality
wood fuel is carbon lean because a
small amount of fossil fuel is required
as part of the production process – e.g.
to power machinery or in transport.
Climate change
Climate is how the atmosphere
"behaves" over relatively long time
periods. The term weather descirbes
atmospheric conditions over a short
time period. Climate change means
changes in the long-term average of
daily weather.
Coppicing
This is a traditional method of
sustainable woodland management in
which young tree stems are repeatedly
cut down to near ground level. In
subsequent growth years many new
shoots emerge and after a number of
years the coppiced tree or stool is ready
to be harvested and the cycle starts
again.
Deforestation
A change in land use from forested to
non-forested land.
Carbon Sink
The term ‘sink’ is used to mean any
process that removes a greenhouse
gas from the atmosphere. A forest is a
sink only while the carbon stock
continues to increase.
Carbon Store
Wood products are a store of carbon,
as they themselves do not capture
carbon dioxide from the atmosphere,
but keep it locked up throughout their
lifetime.
Emissions/Emission scenarios
The emissions referred to are
greenhouse gas emissions. Climate
change scenarios are produced by the
UK Climate Impacts Programme every 6
years. These are based on various
scenarios depending on whether
greenhouse gas emissions are
reduced, stay the same or increased.
Go to the UKCIP website for more
information: http://www.ukcip.org.uk/.
Greenhouse effect
This is the process by which
greenhouse gases in the Earth’s
atmosphere warm the Earth by
absorbing some of the radiation
emitted by the Earth’s surface and
preventing it escaping back outside the
Earth’s atmosphere.
Life cycle analysis (LCA)
An LCA is the investigation and
valuation of the environmental impacts
of a given product or service caused by
its existence.
Locking up carbon
Forests are often referred to as “locking
up carbon” because they absorb
carbon in the form of carbon dioxide
from the atmosphere, and store it in
their wood, soils, roots, leaves and
seeds.
Mitigation
The term mitigation refers to all activities
aimed at reducing greenhouse gas
emissions and/or removal of carbon
dioxide from the atmosphere.
Offsetting
Carbon offsetting describes the process
of reducing greenhouse gas emissions
by purchasing credits from others for
products that seek to reduce emissions,
emissions reductions projects e.g. tree
planting, or carbon trading schemes.
Phenology
This is the study of periodic plant and
animal life cycle events and how they
are influenced by seasonal and
interannual variations in climate. In a
changing climate the timing of events
such as bud-burst may be altered.
Provenance
Provenance refers to the source of the
planting material in question. In this
context for example, oak of French
provenance might be better suited to a
warmer climate than oak of English
provenance.
Resilient woodlands
Refers to woodlands that are able to
adapt to and withstand climate change.
Sequestration
This is the storage of carbon (usually
captured from atmospheric carbon
dioxide) in a solid material through
biological or physical processes.
Substitution
Using one material in place of another,
in this context using wood as a product
instead of materials like concrete or
steel.
Sustainable woodland management
Sustainable woodland management
practices seek to balance the wide
range of benefits that woodlands
provide, including biodiversity,
recreation and effects on the carbon
cycle. Management takes the form of
cyclical harvesting and growing – trees
that are cut down are allowed to
regenerate naturally, or more are
planted in their place. Well-managed
woodlands generally have higher
carbon stocks than stands that are not
harvested.
Urban heat island
An urban heat island is a built up area
that is significantly warmer than
surrounding rural areas. The main
cause is modification of the land
surface by urban development.