Focus: If you can't stand the heat...

...then stay indoors, keep the curtains drawn, and chill out with the 'Independent on Sunday' guide to everything you need to know about our crazy climate. Take your time - weather forecasters say that the unusually high temperatures will last well into next week... The science of global warming

As long ago as 1967 the meteorologist Sir John Houghton was delivering papers on the worrying effect of carbon dioxide on the Earth's atmosphere, and what it would mean for the world's climate. The heatwave that struck Britain and wide areas of the Continent last week may be just the latest sign that global warming is here - and here to stay unless mankind succeeds in making a supreme effort to stop it before it creates unimagined disaster.

The science of global warming is now accepted by the world's scientific community. The burning of fossil fuels - the basis of day-to-day existence throughout the industrialised world - releases carbon dioxide into the atmosphere. This in turn traps heat from the Sun as it bounces off the Earth's surface, causing temperatures to rise and triggering a series of other climatic changes that add up to what Sir John calls "the biggest challenge we face". Rising sea levels, record-breaking temperatures, floods, melting ice caps and violent extremes of drought and rainfall are all thought to be the result of global warming, which scientists recognise as a man-made phenomenon.

Now retired as the director general of the Met Office, 71-year-old Sir John led the team that in 1990 produced the first authoritative report on the science of climate change. He says there is "no question that we can meet that challenge of global warming" but that it will be the middle of the 21st century, at the earliest, that any efforts to halt it will bear fruit. "Climate is a variable thing, and when records are broken it could just be a sign of natural variability. But you've got to look at the trends. And the average temperature of the whole Earth has been going up steadily since the 1960s."

When scientists predicted that the Earth's temperature would rise by 5C over the course of the 21st century, it was widely assumed that the process would be steady and gradual. It is already clear that it is anything but. "We can expect to have more hot periods," Sir John says. "Only this year there was a heatwave in India with temperatures of 48C that went on for 27 days and killed 1,600 people. So that is serious stuff." The world's response to global warming may be regarded as too little too late, but Sir John thinks it is "remarkable we have responded as much as we have". With its infamous refusal to sign up to the Kyoto protocol that committed countries to reducing their levels of carbon dioxide emissions, the United States, which produces 25 per cent of the world's emissions in spite of having only 3 per cent of the world's population, remains the chief obstacle to progress.

Other signs are more encouraging. BP and Shell are investing hugely in research into renewable energy. The Government is rolling out a programme of North Sea wind-farms as it aims to fulfill its commitment to keep emissions in 2010 at the same level as in 2000, and to ensure that by 2010, 10 per cent of the energy Britain uses is renewable. Cars powered by electricity or hydrogen are on their way; in Brazil, cars are being developed that run on sugar-beet alcohol.

"The world won't come to an end, but the incidence of disasters will have a very big impact, and in ways we can't predict," Sir John says. "Rises in sea levels will displace millions of people. It's estimated there will be 150 million refugees by 2050, homeless as a result of global warming. It's how we deal with these problems that is as much the challenge as tackling the causes of global warming."

Boiling Britain

* Ozone levels were almost double their normal summertime levels in London last week as the gas was created by sun shining on pollutants in the atmosphere.

* Otters at the National Sea Life Centre in Birmingham cooled down by rolling around in a vanload of snow ordered in a hurry from an indoor ski centre.

* Two trials were adjourned when the air conditioning at Leicester Crown Court failed to cope. "It would be far more humane to send you home," one judge told a jury.

* The London Eye was shut down for the first time in three years "for the comfort of guests" when the pods became overheated.

* It was still not quite hot enough for the many punters who bet on temperatures reaching 100F (37.8C). "This is the biggest gamble on the weather we have seen," said Ladbrokes, but the highest mercury recorded was at 96.6F.

* Coastguards had a hectic day in the south, receiving 30 calls from boats in trouble and more from swimmers. "Crazy" was how they described the teenagers who jumped into the sea from the top of a 50ft helter-skelter on Brighton pier, despite rocks just beneath the surface.

* Hospital workers in Manchester endured the heat without air conditioning or fans, banned by their health trust. They were told to press damp towels to their heads and necks instead, or immerse their arms in cold waterto keep cool.

* Water companies were alarmed at how much we used in the heatwave. Demand in the north-west was up by 200 million litres a day, while in the Thames region it was compared to 28 million baths.

* Lollies made with blood and ice were fed to lions and tigers at London Zoo, while bears were given pops made with frozen nuts and fruit. Meanwhile, a seal was spotted sunbathing on the banks of the Thames near Hammersmith Bridge.

* Researchers at Imperial College, London, declared they had worked out how to keep a house cool - open the windows. Opening sash windows equally at the top and bottom allows hot air to escape and cool air to enter, apparently.

Too hot to move

* A train driver applied the brakes in a hurry on Wednesday as he spotted that rails near Gatwick airport had buckled in the heat. Net- work Rail said there had been at least 11 other instances of buckling tracks, and imposed speed restrictions of 60mph from noon to 7pm across southern England and the Midlands, causing delays.

* Virgin cancelled 20 services on the west coast mainline to prevent a logjam. There were also 17 Great Western services cancelled, and disruption to Great North Eastern Railways and Silverlink. The 60mph restriction drew widespread criticism, especially as Eurostar trains continued to be tested at 186mph on the new high-speed link through Kent. "It seems incredible that a few degrees more on the temperature gauge can bring chaos to our rail-ways," said the Liberal Democrats' transport spokesman Don Foster.

* An overheating commuter stuck on a train from Basingstoke to Waterloo for nine hours smashed an emergency exit to allow air into the carriage. Others - including a pregnant woman - complained of "greenhouse" conditions on board the service which left at 9.20am and finally trundled into London at 6.20pm.

* The AA warned motorists to beware of melting tarmac, but still took 1,200 calls from stranded drivers as daytrippers dashed to the coast causing jams on the M23, M4 and M3.

* A Concorde supersonic airline on its way from London to New York was forced to make an unscheduled stop in Canada. The journey took an extra 90 minutes. High temperatures mean the air it flies through is of a higher pressure and therefore the jet uses more fuel.

* Police officers in Berkshire bought every available bottle of water from supermarkets and service stations and ferried them to motorists trapped in a traffic jam on the A34. The six-mile queue formed when two lorries collided spilling gallons of diesel on to the road near Newbury.

Tips for survival

The top 10 tips for surviving the heat from the Department of Health are:

* Stay in the shade or indoors. The sun is at its most dangerous between 11am and 3pm.

* Use sunscreen and cover up. Apply at least factor 15 and wear a T-shirt, hat and sunglasses.

* Drink more than the normal recommended daily intake of 2.5 litres or at least eight glasses of water.

* Ventilate your home. Keep windows open all day and all night and use fans, particularly at night.

* Look after the elderly. Check that relatives and neighbours are drinking plenty of tea, water and fruit juice and keeping their home cool.

* Protect children. Check if they are drinking enough by making sure urine is regular and not too dark. Keep babies and the very young out of the sun.

* Avoid excessive physical exertion. Drink half a litre of fluid at least half an hour before exercise and replenish fluids later.

* Know the perils of outdoor eating. Warm weather breeds bacteria so store foods until ready to eat. Barbecue meat until it is piping hot and juices run clear.

* Be sensible with alcohol. Hot weather speeds up the effects of alcohol which will lead to dehydration.

* Keep cool at work. Ask your boss for air-conditioning or fans and open windows where possible. Have plenty of breaks.

What they're saying

It is bizarre that Britain should be leading the world in taking action against global warming when we would benefit more than anybody; a rise of 2F would merely take our climate back to medieval times, when Northumbrian monks were knocking back home-made wine - Leader in The Spectator

One has to look on the bright side and view summer smoggery as a glass not so much half empty as tantalisingly obscured. Dickens wrote approvingly of fog as "London's ivy", while Monet, Turner, Whistler and company went wild over the ethereal and euphemistic elegance it lent to its surroundings - Leader in The Times

It's bloody hot - Prince Charles to workers at an Glasgow engineering firm

I would rather not be arrested simply because it slows me down and I am hoping to get to John O'Groats before September because it might be a bit chilly then - Naked rambler Steve Gough

We're snowed under - Receptionist at the Met Office on the number of inquiries last week

This does seem to be a fairly extreme episode - Geoff Dollard, technical director of the Government's independent pollution monitoring group

Global warming is becoming part of the present. Bizarrely, the weight of the evidence required for policy-makers around the world to act decisively is not great enough for the world's greatest polluter, America - Leader in The Guardian

If Tony Blair's foreign policy is to have an ethical dimension, he must make Russian ratification of the Kyoto protocol on greenhouse gases an absolute priority - Roger Higman, senior climate campaigner at Friends of the Earth