Global warming: the science

Last edited 30 October 2001 at 9:00am
Polar bear threatened by climate change

Polar bear threatened by climate change

Global warming is the biggest environmental threat we face.

For years, scientists argued over the evidence and governments refused to accept that global warming was happening. But there is no longer any doubt that our use of fossil fuels to meet our energy needs is changing the climate, with potentially catastrophic results.

Climate change: the facts
Since the industrial revolution we have massively increased the burning of fossil fuels - oil, coal and gas - to power our factories, heat our homes and drive our cars. When fossil fuels are burned, they release carbon dioxide (CO2) - the main human-made greenhouse gas.

CO2 and other greenhouse gases create an artificial greenhouse effect, thickening the natural canopy of gases in the atmosphere and causing more heat to become trapped. As a result, the global temperature is increasing, throwing the world's climate out of its natural balance and into chaos.

Some industrial chemicals have the potential to damage the atmosphere thousands of times more than CO2, such as hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) used in refrigeration.

Today, concentrations of CO2 are 30 per cent higher than before the industrial revolution. While many greenhouse gases occur naturally, this rate of increase is far from natural.

The result? The weather starts changing and we see all kinds of extreme weather events, from the 2003 heatwave in Europe, which killed 30,000 people, to increasingly severe hurricanes. Plant and animal species die out, unable to adapt fast enough.

How long have we got?
We are already committed to some changes in our climate, and we are already seeing the impacts worldwide. But it's not too late to prevent the worst effects of global warming.

Scientists have predicted that if the average global temperature rises more than two degrees celcius above pre-industrial levels, the risks of abrupt, accelerated or runaway climate change rise, increasing the number of people at risk from water shortages, food shortages and disease, and causing irreversible damage to vital ecosystems.

The International Climate Change Task Force has calculated that we have just 10 years left to stabilise the concentrations of greenhouse gases in our atmosphere and start bringing them down, in order to stay within that 2 degree limit.

Isn't this just the opinion of Greenpeace and a few crazy environmentalists?
Far from it.

No fewer than 150 governments have accepted the findings of the Intergovernmental Panel on Climate Change (IPCC), a panel of 2000 world renowned scientists set up by the United Nations in 1988. The IPCC's last major report in 2001 provided a clear warning that the first signs of human induced climate change are occurring and that the risks posed are enormous if we continue to burn fossil fuels at the current rate.

What can you do?
Climate change is killing 160,000 people every year. Within 50 years, one-third of all species could face extinction. We're the last generation that can stop it from reaching a catastrophic tipping point.

We have the means to stop it - not we need the political will. Tony Blair is currently reviewing the UK's energy policy and, instead of taking real steps to tackle climate change, wants a new generation of nuclear power stations. Nuclear power will cost the Earth and won't stop climate change. But there is a cleaner, cheaper, more secure option.

Make your voice heard now. Write to your MP to state your opposition to nuclear power and support for renewable energy and energy efficiency as the cheapest, safest, most effective solution to climate change.

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