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Sustainable Cheshire Forum Climate Change Guide |
What
is climate change?
Climate change is the phrase used to describe the changes we are causing in our atmosphere as a result of human activities. These activities are based on the burning of fossil fuels and result in the production of carbon dioxide (CO2) and other pollutants, also known as greenhouse gases. The concept of climate change has also been known in the past as the Greenhouse Effect or Global Warming.
What causes
climate change?
Human activity has changed the concentration of greenhouse gases in
the atmosphere in two important ways. First, we have cut down forests
to develop land for agriculture. Trees absorb CO2 so, with fewer trees,
more CO2 builds up in the atmosphere. Second, by burning fossil fuels
like coal, oil and gas for energy, we release greenhouse gases. Currently,
burning fossil fuels emits about 6.5 billion tonnes of CO2 into the
atmosphere each year. Today, CO2 levels are at 380 parts per million
(ppm), 100 ppm higher than before the Industrial Revolution and greater
than they have been for over a million years.
What effects
will climate change have?
The increasing levels of CO2 will cause the planets temperature to rise.
However, there is a time lag between when the emissions occur and when
we begin to feel their effects, so we have yet to experience the impact
of the greenhouse gas emissions from the last 30 to 40 years. The warming
of the planet caused by the increased CO2 will upset its natural systems
and result in changes to the weather, ice caps and water resources.
These changes will in turn have wide ranging effects on human health,
agriculture, plants and animals, businesses and communities.
Temperature
Over the past century, average global temperatures have already risen
by 0.7°C. In the UK, the climate will continue to become warmer,
with hotter summers and fewer cold winters. By 2080, it is possible
that the Northwest will experience an average increase in temperature
of 4 or 5°C. This may not sound like much, but this change in temperature
has been enough in the past to bring our planet out of the Ice Age.
The ten warmest years on record have all been since 1990. In the UK
during August 2003, the hottest temperature ever recorded was measured
in Kent, it was 38.5°C. These temperatures are expected to become
the norm by 2050.
Rainfall
In general, winters will become wetter and summers drier, with increased
risk of flooding in winter and drought in summer. We will also see progressively
less snow in winter. In the Northwest, by 2080 we could have 40 - 60%
less rain in summer and 15 - 30% more rain in winter. The winter floods
in 2000 were the worst for 270 years in some areas of the UK. Flooding
of farmland cost the farming industry nearly £500 million.
Sea level
The sea level could rise by more than 40 cm by the end of the century.
There are two reasons for this. Firstly, as the water in the oceans
warms, it expands. Second, ice from the polar caps and from glaciers
is melting into the sea. Rising sea levels will not only affect small,
low-lying islands; many of the worlds largest cities are located on,
or close to, the coast. Increased sea levels will also have a significant
effect on Englands Northwest as the 430 km of coastline is generally
low-lying. As sea levels rise, this will have a knock on effect on river
and stream levels, potentially affecting other areas of the County.
Water
resources
There will be less water available for irrigation and drinking because
there will be less rain in summer, and salt from rising sea levels will
contaminate ground water in coastal areas. Droughts are likely to be
more frequent. Around the world, three billion more people could suffer
increased water shortages by 2080 and deserts are set to grow.
Agriculture
As temperatures increase and rainfall patterns change, cereal crop yields
are expected to drop significantly in Africa, the Middle East and India.
In the Northwest, we will see a change in the success of traditional
crops and the introduction of new crops. Soil quality may suffer as
a result of heavy rainfall causing increased erosion. New pests and
diseases will also have an effect on food production.
Health
As temperatures increase, the areas that harbour diseases such as malaria,
West Nile disease, dengue fever and river blindness will shift. It is
predicted that 290 million additional people could be exposed to malaria
by the 2080s, with China and Central Asia seeing the biggest increase
in risk. In the UK there will also be noticeable effects on health.
Although there will be fewer winter deaths from the cold, there will
be an increase in the number of summer deaths due to the increased temperatures.
For example, in the first half of August 2003 over 2,000 people in the
UK died as a result of the unprecedented heat.
Plants and animals
Higher temperatures and reduced rainfall could mean the loss of large
areas of Brazilian and southern African rainforest. These forests currently
act as a 'sink' by absorbing large amounts of CO2 which would otherwise
be released into the atmosphere. The UK will also experience loss of
plants and animals from their traditional locations as the temperature
increases. Many species will move further North and uphill to try to
stay within their temperature range. The most vulnerable species will
be those that already have a restricted range in the Northern most parts
of the UK, including those that live in the rural uplands of the Northwest.
There will also be migration of new species into the region, which has
already started due to warmer temperatures. Coastal waters have also
warmed, changing the distribution of important commercial fish species
and other marine animals
Business
The water and energy industries will face new challenges with the changing
climate. Whilst many businesses will enjoy reduced heating bills in
winter, many will have the increased cost of cooling in summer. Working
conditions will also become more unpleasant in many manufacturing industries.
As 25% of the UK's chemical industry is based along the Northwest coastline,
there will be particular risks in terms of flooding and consequently
insurance costs for many businesses. However, some of the impacts of
climate change could be potentially beneficial for business, creating
new market opportunities and growth into new sectors.