While we can take measures now to curb greenhouse gas emissions, the benefits won’t be apparent for some time. It is inevitable that past emissions will cause changes to our climate over the next 30 to 40 years.
In the UK, mean annual temperatures are expected to rise by between 3ºC and 6ºC by the 2080s. Winters will see substantially fewer frosts. Summer rainfall could fall by 50 per cent and winter rainfall increase by between 10 and 40 per cent. Thus, summer droughts and winter flooding may become more common. While these predictions are subject to many uncertainties, it is already clear that there will be a significant impact on our trees and forests.
The scale and rate of change is also likely to vary between regions: Scotland, northern England and much of Wales could see increased timber productivity because of rising carbon dioxide levels, a longer growing season, and a generally warmer climate. Whereas in other areas of England, an increase in the frequency of summer droughts may reduce growth rates of many tree species. The character of our native woods is also likely to change.
MOVIE: Climate change predictions for the UK.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.
Pest and disease outbreaks could well turn out to be more serious than the effects of other changes to our climate. Trees under stress are more susceptible to harmful insects 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.
We need to plan ahead for these changes. We need to design and manage forests and woodlands to cope with the new climate, ensuring that they continue to provide the products and services that people want.
- Climate change is already happening.
- The reductions we make to our CO2 emissions now will not take effect for many decades.
- We need to give careful thought to the type of trees that we grow.