Human activity is the main cause of the changes seen in climate. The world's climate varies naturally as a result of:
However, there is now strong evidence and almost universal agreement that significant global warming can't be explained just by natural variations. The changes seen over recent years, and those predicted for the next 80 years, are thought to be mainly as a result of human behaviour.
The Intergovernmental Panel on Climate Change (IPCC) is a scientific body set up by the UN to look at climate change. It says that human activity is the main cause of the changes seen in climate.
The greenhouse effect
The earth is surrounded by a layer of gases which act like the glass walls of a greenhouse. These gases let the sun's rays enter, but stop much of the heat from escaping. This is a natural process, and it's these 'greenhouse gases' (mainly carbon dioxide and water vapour) that keep the planet warm enough to sustain life.
However, as humans cause more greenhouse gases to be released into the atmosphere, the greenhouse effect becomes stronger. More heat is trapped and the earth's climate begins to change unnaturally.
Since the Industrial Revolution, which began in the 18th century, the amount of carbon dioxide (CO2) in the atmosphere has increased by 35 per cent. In fact, the concentration of CO2 is now higher than at any point in the past 650,000 years.
Why greenhouse gases have increased
Deforestation produces 18 per cent of global CO2, Human activity is changing the amount of greenhouse gases in the atmosphere in three important ways:
1. Forests are being cut down
Trees absorb carbon dioxide so, with fewer trees, more carbon dioxide builds up in the atmosphere. Also, the agriculture and industry that replaces the forests can often be a source of emissions. The Intergovernmental Panel on Climate Change (IPCC) estimates that deforestation produces 5.9 billion tonnes of CO2 per year or 18 per cent of global CO2.
2. Fossil fuels are being burned
Burning fossil fuels like coal, oil and gas - to generate heat or to power transport for example - releases greenhouse gases. In 2005, burning fossil fuels emitted about 27 billion tonnes of carbon dioxide.
3. The world's population is growing
growing population is leading to an increased demand for food, livestock and energy, which is in turn leading to increased emissions.
The main contributors to climate change in the UK
In the UK, around:
About 40 per cent of emissions in the UK are the result of decisions taken directly by individuals. The biggest sources of emissions for most people are likely to be:
Other things in people's homes contribute to climate change indirectly. Everything, from furniture to computers, from clothes to carpets, uses energy when it is produced and transported - and this causes emissions to be released.
The UK has passed legislation which introduces the world's first long-term legally binding framework to tackle the dangers of climate change. The Climate Change Bill was introduced into Parliament on 14 November 2007 and became law on 26 November 2008. The Climate Change Act creates a new approach to managing and responding to climate change in the UK, by:
In March 2009, the Climate Change Act Impact Assessment was updated to reflect the final contents of the Act. Two key aims of the Act:
Key provisions of the Act
Government acts to combat climate change
The UK faces unprecedented challenges to our environment, our economy, and the future security of our energy supplies. The decisions we make now will affect the planet and our way of life for generations to come. Here are some of the ways in which Government is working to act on these climate change challenges.
Passing the Climate Change Act
When it became law in November 2008, the Climate Change Act set in legislation a target for the UK to cut greenhouse gas emissions by 80% by 2050. It also introduced five-year carbon budgets as a tool to achieve this target and set up the independent Committee on Climate Change (CCC).
Setting carbon budgets
Carbon budgets are legally-binding limits on the greenhouse gas emissions which will help drive the UK's transition to a low-carbon economy - and the UK is the first country in the world to implement them.
The UK's first carbon budgets were negotiated in the past year by the Department of the Environment and Climate Change (DECC) across Whitehall and were announced in the 2009 Budget. To ensure the budgets are met, the Government will have to put in place wide ranging policies to reduce emissions in all sectors of the UK.
The UK has already reduced emissions significantly, but - with even more challenging targets to meet - carbon budgets will act as stepping stones to our longer-term emissions targets.
Moving the UK onto a low-carbon footing
The UK was the first country in the world to produce a comprehensive plan to move the UK onto a permanent low-carbon footing.
Educating the public through the Energy Saving Trust
The Energy Saving Trust (EST) tries to prevent climate change by helping everybody in the UK cut carbon dioxide emissions - the main greenhouse gas - from their homes. Through its advice centres and website, the EST promotes the efficient use of energy and a more low-carbon lifestyle. EST was set up by the Department of Energy and Climate Change (DECC).
Providing financial help through the Warm Front scheme
Warm Front is the Government's flagship fuel poverty programme which provides grants to householders on certain benefits, including pension credits. It allows those who receive help to make improvements to their central heating and install energy efficiency measures, such as insulation.
Climate change is one of the most pressing issues facing the planet - and one everyone can do something about. From turning the thermostat down to buying a more economical car, there are many steps you can take to help safeguard the future of the planet.
What is climate change?
'Climate change' refers to changes in the earth's temperature over the last 100 years. Since 1900, the average temperature on the planet has increased by 0.74 degrees Celsius and the UK's sea level has risen by about 10 centimetres. Further global rises are expected, as well as more extreme weather events like flooding and drought.
Individuals are responsible for about 40 per cent of emissions in the UK. The biggest sources are energy use in the home, driving and air travel.
Challenging climate change myths
Isn't the climate constantly changing? There's no scientific evidence for climate change, is there? Isn't it too late to make a difference? Confusion about climate change is widespread. Explore some of the most common misconceptions and the facts behind them.
What you can do about climate change
The European Union has proposed that global temperature rises need to be limited to two degrees Celsius to avoid dangerous climate change. This can be achieved by cutting emissions, and there are many ways you can help achieve this, through greener living.
What's being done about climate change
People all over the UK have been working to tackle climate change. They have pledged to lower their own emissions and even decided to make their village, town or football team carbon neutral. In 2008 the UK passed the Climate Change Act to tackle the dangers of climate change.
Brief history of climate change
Tackling climate change is one of the biggest challenges this generation faces, and the zafirst step is to understand exactly what it is. Find out how climate change was first detected, the history of efforts to tackle it and the latest developments.
What is climate change?
The climate is not static; over the millions of years of earth's existence, it has changed many times in response to natural causes.
When people talk about 'climate change' today, however, they mean the changes in temperature over the last 100 years. During this time, the average temperature of the atmosphere near the earth's surface has risen by 0.74 degrees Celsius.
Most scientists agree that global temperatures will rise further - by how much depends on future emissions of greenhouse gases. If the temperature rise is high, changes are likely to be so extreme that it will be difficult to cope with them. There are likely to be more intense and frequent extreme weather events, like floods and hurricanes, and sea levels could rise further.
Early discoveries about climate change
The first discoveries that helped explain climate change happened in the 18th and 19th centuries:
First warnings about climate change
In 1967, a computer simulation calculated that global temperatures might increase by more than 4 degrees Fahrenheit, depending on carbon dioxide levels. 20 years later, an ice core from Antarctica revealed a link between carbon dioxide levels and temperature going back more than 100,000 years. Warnings like these encouraged international action on climate change.
The world's response to climate change
In 1979, the world held its first climate conference. The conference called on governments "to foresee and prevent potential man-made changes in climate".
United Nations takes action
In 1988, the United Nations set up the Intergovernmental Panel on Climate Change (IPCC) to analyse and report on scientific findings. The IPCC warned that only strong measures to stop greenhouse gas emissions would prevent serious global warming.
Global targets for reducing emissions
In 1992, the Earth Summit took place in Rio de Janeiro. Here, the United Nations Framework Convention on Climate Change (UNFCCC) was signed by 154 nations. It agreed to prevent 'dangerous' warming from greenhouse gases and set voluntary targets for reducing emissions. The UK is one of a small number of countries which met this voluntary target.
Kyoto: legally binding cuts in emissions
In 1997, the Kyoto Protocol was agreed. Where the UNFCCC agreed voluntary targets, Kyoto was the first international treaty to set legally binding emissions cuts for industrialised nations. It was signed by 178 countries and came into force in 2005.
The UK's reaction to climate change
The UK signed both the UNFCCC and the Kyoto Protocol, and is on track to exceed its Kyoto target for reducing greenhouse gas emissions. In 2006, the Stern report was published in the UK by HM Treasury. It was the first report of its kind into the economic impact of climate change. It found that the costs of inaction far outweighed the costs of action. In November 2008, the UK government passed the Climate Change Act. The Act sets legally binding targets for reducing emissions by 80 per cent on 1990 levels by 2050.
Latest international action on climate change
In 2007, the IPCC announced that the planet has warmed 0.74 degrees Celsius since the beginning of the 20th century. It said there is a greater than 90 per cent chance that global warming over the last 50 years is due to human activity.
At the 2007 UN climate change conference in Bali, the world's nations agreed to negotiate on a deal to tackle climate change. This agreement would replace the Kyoto Protocol and the details were expected to be agreed at Copenhagen in 2009.
What you can do about climate change
Some changes to the climate are inevitable, but there is still time to have a positive influence on the future. You can help minimise further changes and adapt to the new situation through your decisions and actions.
Myths about climate change
Confusion and myths about climate change are widespread, here we explore some of the most common misconceptions and the facts behind them.
The climate is always changing anyway
The majority of scientists are convinced that humans are affecting the climate by the way they live. The Met Office Hadley Centre is the UK's official centre for climate change research. They recently carried out a study that found today's temperatures could only be the result of human activity. Science has shown that greenhouse gases keep the earth warm, that there is evidence concentrations of these gases are increasing, and that humans are responsible for these increases by burning fossil fuels and cutting down forests.
It's too late to make a difference
The last report from the IPCC indicated that global emissions must peak in the next decade or two and then decline to well below current levels by the middle of the century if we are to avoid dangerous climate change. This is possible, and can be achieved with technologies that are available now. Putting off action to cut greenhouse gases will make it more difficult and costly to reduce emissions in the future, as well as creating higher risks of severe climate change impacts.
There's no point in me taking action
Every reduction in emissions makes a difference by not adding to the risk. Countries like the UK are in a position to give a positive example to the rest of the world - if the UK can rise to the challenge successfully, others will follow.
Climate change will make life more comfortable in the UK
Climate change will lead to warmer winters, but temperatures will become uncomfortably hot in summer, and the climate may also be unpredictable and extreme. There's also the risk of rising sea levels and extreme weather like storms and floods. Tackling climate change and securing a more stable climate will make life a lot more comfortable.
It would cost too much to tackle climate change
Tackling climate change needn't damage the economy as a whole. Industry will have to adapt and jobs may change - but more may be created overall. Using less energy can also save companies and households money.
Not tackling climate change has a price too. The recent Stern report examines the economic impact of climate change. It estimates that not taking action could cost from five to 20 percent of global GDP every year, now and forever. In comparison, the cost of reducing emissions to avoid the worst impacts of climate change can be limited to around one per cent of global GDP each year.
"The full review by de Poel ensured the delivery of a more productive and happy workforce as they identified a very efficient process of getting the right people for the right jobs"
