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.
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.
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.
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.
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.
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.
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
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.