• What is climate change?
• What causes climate change?
• What can we do about climate change?
• Challenging myths
• A brief history of climate change
• Climate change in the UK

What is climate change?

Click here to watch an educational animation created by DEFRA

Our planet is surrounded by a blanket of gases which keeps the surface of the earth warm and able to sustain life. This blanket is getting thicker, trapping in heat as we release greenhouse gases by burning fossil fuels for energy and as we cut down forests and replace them with agricultural land. As a result, our climate is starting to change. Scientific research indicates that, because of climate change, we may experience more intense and more frequent extreme weather events. A gradual increase in temperature also has major implications for ecosystems, growing seasons, animals and their habitats.

What causes climate change?

There is now strong evidence and almost unanimous agreement that significant global warming is occurring. It is also likely that most of the recent warming can be attributed to human activities.

Natural Causes

Some changes to the earth's climate are caused by the effects on each other of the sun, land, oceans and atmosphere. These occur over very long periods of time.

Human causes

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 carbon dioxide so, with fewer trees, more carbon dioxide builds up in the atmosphere. Also, the agriculture that replaces the forests can often be a source of emissions.

Second, by burning fossil fuels like coal, oil and gas for energy, we release greenhouse gases. Since before the industrial revolution, which began in the 18th century, concentrations of greenhouse gases have increased by 30 per cent.

What can we do about climate change?

Many scientists believe that emissions of greenhouse gases, which are continuing to rise, must begin to decline over the next 10-20 years to avoid extreme changes to our climate.

Carbon dioxide is the main greenhouse gas that causes climate change. Every tonne emitted into the atmosphere commits the world to more warming. But every tonne we avoid emitting helps reduce the risk.

The good news is there are lots of ways we can tackle climate change. Many of them will bring other benefits, such as new jobs, improved local environments and economic growth.

Key climate facts

Big changes in the atmosphere

Concentrations of greenhouse gases are now higher than at any point in the past 800,000 years.

Hot decade

The ten warmest years on record have all been since 1990. In Europe, the August 2003 heatwave was probably the hottest for at least 500 years. Between 4 and 13 August, over 2000 people in the UK died as a result of the heat.

Big increase in flood victims

The autumn and winter floods in 2000 in the UK were the worst for 270 years in some areas.

Challenging myths

"The climate is always changing"

It is true that natural changes in the world's climate have happened in the past - but it is sometimes overlooked that in extreme cases this resulted in mass extinction! What we are dealing with now is potentially a big change in our climate that we ourselves have caused. Concentrations of heat trapping greenhouses gases in our atmosphere are now higher than they have been at any point in the last 800,000 years. Although this may not be new in relation to the history of the planet, it is entirely new in human history. It doesn't mean the world will end, but it could make the world a hostile place that cannot sustain life as we know it.

Scientists who question whether climate change is happening are now few and far between.

Myth 1 - Human activity doesn't cause climate change

The majority of scientists are convinced that we are affecting the climate by the way that we live.

Myth 2 - It's too late to make a difference

There are some changes that have happened which cannot be reversed. However, by acting now, we can reduce the risk of big changes occurring to our climate and reduce the impacts that we and future generations will experience.

Myth 3 - There's no point in me taking action

In fact, every reduction in emissions that takes place, no matter where it occurs, makes a difference by not adding to the risk. Also, some countries like the UK are in a great position to give a positive example to the rest of the world. We do need other countries to join in, but if we can show that we can rise to the challenge successfully and make a real difference, others will follow.

Myth 4 - Climate change will make life more comfortable in the UK

Climate change may lead to a warmer climate overall in the UK. But the climate may also be unpredictable and extreme, which will unpleasant for many people. We may have warmer winters, but they are also likely to be wetter. And in the summer, excessive heat will cause problems for the elderly, the very young and those with health problems. Tackling climate change and helping to secure a more stable climate for ourselves will make life a lot more comfortable for us all in the end.

A brief history of climate change

1827 GREENHOUSE EFFECT: Jean-Baptiste Fourier suggests the existence of an atmospheric effect keeping the earth warmer than it would otherwise be. He uses the analogy of a greenhouse.

1896 GLOBAL WARMING: Arrhenius, a Swedish chemist, advances the theory that carbon dioxide emissions from combustion of coal would enhance the earth's greenhouse effect and lead to global warming.

1967 GLOBAL TEMPERATURE WARNING: the first reliable computer simulation calculates that global average temperature may increase by more than 4 F when the atmospheric carbon dioxide level reaches double that of pre-industrial times.

1992 CLIMATE CHANGE AT RIO EARTH SUMMIT:The Framework Convention on Climate Change (FCC), signed by 154 nations in Rio de Janeiro, agrees to prevent ‘dangerous' warming from greenhouse gases and sets initial target of reducing emissions from industrialised countries to 1990 levels by the year 2000. President George Bush (Senior) signs on behalf of the United States.

1987 ICE-CORE EVIDENCE: An ice core from Antarctica analysed by French and Russian scientists reveals and extremely close correlation between carbon dioxide levels and temperatures going back more than 100,000 years.

2001 KYOTO PROTOCOL: The Kyoto Protocol agrees legally binding emissions cuts for industrialised nations, averaging 5.5%, to be met by 2010.

2005 KYOTO PROTOCOL SIGNED: On 27 July, 178 countries give life to the Kyoto Protocol.

KYOTO PROTOCOL RATIFIED: 16 February. On the 90th day after at least 55 Parties to the Convention (responsible for at least 55% of the total carbon dioxide emissions for 1990) deposited their instruments for ratification, acceptance, approval or accession, the Kyoto Protocol came into force.

This map depicts the countries that have ratified or signed the Kyoto Protocol as of June, 2003. Ratifying countries are indicated in green. Those countries that have signed, but not ratified the Kyoto Protocol are indicated in dotted yellow. Those countries that have neither signed nor ratified the agreement are depicted in red.

UK climate change

What does climate change mean for us here in the UK?
The evidence for climate change in the UK comes from weather records extending back over 350 years. From these, it's clear that the 1990s were the warmest decade in central England since records began in the 1660s. Coastal waters have also warmed, changing the distribution of important commercial fish species and other marine animals.

A range of effects

A Variety of other changes to the UK climate include:

• The growing season for plants in central England is now a month longer than it was in 1900.
• Summer heatwaves are occurring more frequently, and in winter there are fewer frosts.
• Compared with 50 years ago, we now get more rain and snow, and on fewer days - so they are even heavier.
• Average sea level around the UK is now about 10cm higher than it was in 1900.

Climate models predict the sea level will rise and flooding will increase. In the worst case scenario, this could lead to a great deal of land in the UK becoming uninhabitable. Can you work out where your county would be on this map?