A Convenient Truth: Script
Temperatures are rising.
The twentieth century was possibly the warmest century in the past thousand years.
The ten warmest years on record have all occurred since 1990.
Rainfall patterns are changing, sea levels are rising, glaciers are retreating and arctic sea-ice is thinning.
The incidence of extreme weather is increasing.
Without action to reduce greenhouse gas emissions global temperatures are expected to rise by between 1.5 and 6ºC by 2100.
Sea level could rise by between 1 and 2 metres.
We have a problem.
We asked our scientists and engineers to develop a machine that soaks up carbon from the atmosphere. A device that would lock up CO2 for quite a long time.
Of course, it would have to be environmentally friendly. It would also have to be efficient, reliable and cheap and easy to produce.
This is what they came up with.
Trees and forests play a crucial role in regulating our climate.
Through photosynthesis they remove CO2 from the atmosphere, binding it and storing it as carbon.
The carbon is held in the forest biomass – in the trunks, branches, foliage and roots and in the soil as organic carbon. The process is constant and is going on all around us.
In young forests carbon is soaked up, or sequestered, quickly. In mature forests sequestration eventually equals decomposition and the carbon balance reaches a steady state.
At this point the forest doesn’t absorb any more carbon but it has become a vast carbon reservoir.
But, if the trees are destroyed, they release carbon back to the atmosphere thus becoming a source of greenhouse gas emissions.
Forests cover just under four billion hectares of the world’s surface. That’s about one third of our total land area.
They forests account for 90 per cent of the annual interchange of carbon between the atmosphere and the land.
The amount of carbon stored in these ecosystems is the equivalent of around 4,500 gigatons of CO2. This is more than the total carbon contained in the world’s remaining oil stocks. More, in fact, than the amount of carbon in the atmosphere itself.
So it’s no surprise that forests can be a big part of the answer to the problem of climate change.
But we’re not looking after them. 8,000 years ago, half of the earth’s land surface was covered by forest. Today, that’s down to less than a third.
Since 1850, deforestation has released around 120 Gigatons of carbon into the atmosphere.
Our own history here in the UK has been one of deforestation. This happened over thousands of years and our forest area reached an all time historic low at the beginning of the last century. At that point, woodland cover in the UK was just 5%.
We rebuilt some of our forest resources. In the last 50 years the UK’s forest area has more than doubled.
Similar patterns of deforestation, followed by reforestation, took place in many other industrialised nations to the extent that forests in these countries are now reabsorbing CO2 again.
The forest area in Europe grew by 13 million hectares between 1990 and 2005. That’s an area roughly equivalent to the area of Greece.
But globally, the forest area is falling – and at an alarming rate. Remember that 13 million hectare increase in Europe that took fifteen years to achieve? Global deforestation accounts for the same amount every year.
Tropical countries are most vulnerable. South America suffered the largest net loss of forests from 2000-2005 – about 4.3 million hectares every year. This was followed by Africa which lost four million hectares per year.
But, as we know from our own experience in the UK, the tide can be turned. Asia, which had a net loss of some 800,000 hectares a year in the 1990s, reported a net gain of one million hectares a year for 2000-2005, primarily as a result of large-scale reforestation by China.
Deforestation doesn’t just exacerbate climate change it affects everyone, particularly the world’s poorest people.
Loss of forests also means loss of biodiversity – two out of three living species depend on our forests.
Those forests provide, among other things, flood protection, erosion control, timber and natural medicines.
It’s a grim statistic but deforestation accounts for nearly ONE-FIFTH of all the world’s greenhouse gas emissions.
That’s more than from every car, every boat, every plane in the world. More than the whole of the whole of the transport sector put together
The forest sector can make a big difference in helping to reverse this situation. Our contribution to climate change mitigation through forest management can come about in three main ways:
• By conserving and managing the existing forests we can protect and maintain the carbon already locked up in them.
• By tackling the causes of deforestation we can reduce the rate and amount of loss of forest cover. Of course, this also protects the ecosystem services that forests provide.
• By restoring the planet’s forest cover through planting new forests and re-establishing those we have lost.
We know how to do this and are sharing our knowledge through the Global Partnership on Forest Restoration to help make a difference at global level.
hile planting can help at a global level it is not a solution on its own. Half a hectare of woodland over one rotation can compensate for the entire CO2 emissions from car fuel consumption during one driver’s lifetime.
But, with 30 million registered drivers in the UK, three quarters of our total land area would have to be covered in forest to make car use alone carbon neutral.
Schemes that encourage individuals, businesses and others to offset their emissions by planting trees can be valuable but mustn’t act just as a salve to our environmental conscience.
Where offsetting can be valuable is when emissions can’t be avoided. People and companies need to know that their money will bring real benefits, real cuts in emissions, actually make a difference. So we need agreed standards to provide that reassurance.
Another thing we can do is to use more wood in our everyday lives. Wood used for energy is bioenergy, something that can replace replace fossil fuels - and the emissions they produce.
The potential is enormous and we must capitalise on that. Of course, forests that supply wood need to be managed sustainably.
In developing countries, wood– usually in the form of fuelwood or charcoal – is the most important source of energy for two billion people. These are mostly poor people who have no access to modern energy services.
Understandably, there is great interest in developing biofuels in developing countries but unfortunately if this means destroying pristine rain forest then it does more harm than good.
With governments committing to fossil fuel alternatives, use of biomass for electricity generation is forecast to triple between now and 2030.
There are also great opportunities for smaller scale wood fuelled heating schemes in areas currently dependent on fossil fuel heating such as oil and coal.
Wood is also a raw material. When it comes to constructing homes and buildings it has the lowest energy consumption and CO2 emission of any commonly used building material.
Replacing one cubic metre of concrete or red brick with the same volume of timber can save around 1 tonne of CO2.
Designing future buildings to use more wood products instead of concrete, plastic and steel could result in a significant drop in greenhouse gas emissions.
Wood products are unique, they come from a natural, renewable, sustainable resource.
The carbon they contain remains stored for the duration of the product’s lifetime until it decays or is burnt. The longer the wood product is used the longer the period of time the carbon is stored within it.
A global increase in the use of industrial wood products would help reduce the amount of CO2 in the atmosphere.
While we can take measures now to curb greenhouse gas emissions, the benefits won’t be apparent for some time. Changes to our climate over the next 30 – 40 years caused by past emissions are largely inevitable.
Lets look at predictions for the UK. Mean annual temperatures are expected to rise by between 3 and 6 degrees by the 2080s. Winters will see substantially fewer frosts.
Summer rainfall could fall by 50%, winter rainfall could increase by between 10 and 40%. Summer droughts and winter flooding may become more common.
More deep depressions could be crossing the country in the winter. Cloud cover in summer, particularly in the south, could reduce leading to increasing amounts of sunshine.
These predictions are subject to many uncertainties but it is already clear that there will be a significant impact upon our trees and forests.
This is a map that shows the predicted change in suitable sites for oak woodland under a high emission scenario. It is quite a dramatic shift.
Changes will vary though from one region to another. Scotland, northern England and much of Wales could see increased tree growth because of rising CO2 levels, a longer growing season and generally warmer climate.
Whereas in other areas of England, more summer droughts could lead to a decrease in the growth rates of many tree species. We will have to look again at the types of trees we grow.
Trees under stress are more susceptible to harmful insect pests and diseases. The majority of insect pests that currently affect UK forestry are likely to benefit from climate change through increased summer activity and reduced winter mortality.
The character of our native woods is also likely to change. Careful consideration will need to be given to species choice, particularly where timber production is important.
In some parts of southern England, some native species will simply no longer be commercially viable.
We need to plan ahead for these changes. We need to design and manage forests and woodlands to cope, and help us cope, with this new climate ensuring they contribute to flood prevention, develop habitat networks and create wildlife corridors.
Looking globally again, action to protect forests can be complemented by action to increase the uptake of CO2 in trees and soils.
Forests need to be managed using sustainable forest practices. Achieving the transition from deforestation to forest conservation and management is a huge challenge.
How do we know that our forests are being managed sustainably?. Well, we have tools to hand.
There are credible forest certification schemes that work. The UK is a world leader in forest certification - we were the first country in the world to have all of our public forests – those managed by the Forestry Commission – independently certified as sustainably managed. Wood from these forests carry a label showing just that.
There’s no doubt that protecting, conserving and managing forests sustainably comes at a cost. It also requires the commitment of resources.
On the other hand, the Stern’s review showed that it can be cost effective. The pressure for deforestation is greatest in a small number of developing countries, but every country in the world gains from maintaining forest resources that provide public goods to the rest of the world.
Finding ways to compensate the countries that provide a global service in this way will encourage conservation.
So developing practical proposals for the sustainable managememt of the world’s forests is essential.
We should be optimistic.
We know what needs to be done:
We need to protect and manage what we already have;
We must reduce deforestation and restore more of the world’s forest cover.
We should use more wood for energy;
And use it in place of other materials.
Finally, we have to plan to adapt to our changing climate.
If we get this right, and play our full part, the world’s forest sector can help to solve this global problem.
Morally, we have always had an obligation to protect and manage our forests for future generations.
We now have the power, and the strongest possible imperative, to do something.
Mankind understands its predicament, has the knowledge to see what needs to be done, has the skills and the technology to do it.
We now have to show we have the willpower too.
