The Easter floods which devastated parts of the English Midlands were believed to be a "once-in-a-lifetime" event.

By the end of the next century, though, they could be happening seven or eight times as often.

That is one illustration the Environment Minister, Michael Meacher, uses to illustrate the seriousness of the report on climate change (Climate Change Scenarios for the United Kingdom).

The report, compiled by scientists working for the UK Climate Impacts Programme, has other graphic examples of what Mr Meacher calls "the very real threat that climate change represents to us".

There are likely to be more frequent and more severe winter gales over parts of the country. The northern half of Britain will become wetter and much of the rain will come in fiercer storms than it does now.

There will be more very hot days, more chance of drought, and an inexorable rise in sea levels.

But Mr Meacher rejects categorically any suggestion that the report is an exercise in scaremongering. "The scientists are being extremely careful", he told me.

"They are not being apocalyptic, and they are not over-egging the pudding. I think they are absolutely right to do that. We must keep rigorously to what the evidence indicates".

At the same time, Mr Meacher accepts that going no further than the evidence allows can have its dangers.

The report looks at the possibility of much more rapid climate change and says it cannot be ruled.

Its authors are especially concerned about two possibilities. One is that the oceans could warm up more quickly than anyone has predicted.

That could mean the Gulf Stream being diverted away from Britain's shores, leaving us with a climate more like northern Canada's.

The other possibility is that the ice sheet surrounding Antarctica could melt faster than present estimates suggest.

Although no reputable scientist is yet suggesting that either of these will happen, nobody will rule them out.

What is happening now is a vast experiment with the climate, and it may yet behave in ways that science can not predict.

Mr Meacher acknowledges that the picture is gradually getting more sombre. "Look at El Nino, the pattern of weather disruption in the Pacific", he said.

"Forty or fifty years ago El Ninos happened about once every five years. Now they are occurring roughly twice as often.

"And the 1997-98 El Nino has been the most extreme recorded. The severity is on the increase".

Adapting to the rate of climate change sketched out in the report would not be "all doom and gloom. There will be gain as well as pain - new jobs, warmer homes for poor people, better air quality".

Mr Meacher praised the way British business is accepting the need to change the way it works, describing it as "pretty responsible".

He stressed the need to save energy, to cut greenhouse emissions from transport, and to produce more electricity from renewable sources, like solar and wave power.