Residents in the Bude and Holsworthy areas had reported hearing a loud bang around midday on Thursday.

One resident in Bude said a crack in her kitchen had widened as a result, while others reported experiencing their properties "shaking".


I'm fairly convinced it was a meteor but the only way to prove it would be to have an audio recording
David Carcary
A BBC Radio Cornwall listener said: "The stables physically shook. It sounded like Concorde used to sound when it broke the sonic barrier. But much louder. It went 'boom, boom'."

Checks carried out by Western Power and the British Geological Survey in the area were inconclusive and the Ministry of Defence, the RAF and the Civil Aviation Authority said there were no records of their aircraft flying over the area.

Mr Carcary believes a similar explosion which shook the south of New Zealand in September was caused by a meteor.

"As soon as I heard the news of the bang, that was the most obvious explanation to me.

"There wasn't any seismic evidence so it burnt out before it hit the ground - luckily for the people of Bude - and if it was an aircraft, I would have expected someone to have seen it.

"I'm fairly convinced it was a meteor but the only way to prove it would be to have an audio recording of the boom."

The international community must limit the atmospheric level of the principal greenhouse gas, carbon dioxide (C02), to below the point where the Greenland ice begins to melt in a runaway manner, Sir David said. This figure is not yet precisely known - but much scientific effort is being expended on finding it out.

Sir David is one of the world's most influential voices on climate change and his suggestion may provide a basis for eventual agreement on one of climate change's thorniest questions: exactly where must the rise in atmospheric C02 - which has gone from 315 parts per million in 1958 to 382ppm today - be halted?

The world community now agrees that the waste gas from motor vehicles and power stations is causing the atmosphere to warm rapidly. But it cannot agree on a precise figure which should be the absolute limit allowable to prevent global disaster.

Some commentators have suggested the C02 level must be halted at 400ppm - but that is now likely to be reached within 10 years and seems impossible to achieve in practice. Sir David has previously suggested 550ppm as "realistic" - but drew criticism for not being more ambitious.

His new suggestion, however, takes a different approach, pinpointing an undeniable disaster level and making that the target - whatever it turns out to be.

Greenland's "tipping point" is not yet known in terms of atmospheric C02 levels, although in terms of temperature it is assumed to be somewhere beyond a global rise of 3C above the level pertaining before the industrial revolution. (Global temperatures currently stand at about 0.7C above pre-industrial, and are steadily climbing). Scientists are seeking it with supercomputer mathematical models of the climate and of the ice mass.

Mystery solved

Researchers at Florida State University and the National Oceanographic and Atmospheric Administration (NOAA) have found that the answer to the mystery lay in a number of factors, including the hurricane's speed and path, influencing a phenomenon called a "trapped wave."

In the Northern Hemisphere, hurricane winds always rotate counterclockwise as seen from above. Earth's rotation pushes ocean water to the right, in the direction of the storm's winds, creating a slight build-up on that side. If the hurricane travels parallel to a coastline on its right side, its winds will force the ocean water against the coast, "creating a bulge of high sea level," explained Steven Morey, a Florida State University oceanographer. This bulge will travel along the coast, forming what is known as a constantly trapped wave.

This was what happened during Dennis: The storm ran alongside the western coast of Florida, allowing the trapped wave to form [ graphic ].

And "because Dennis traveled nearly parallel to the Florida Peninsula coast at the same speed as the wave, winds from Dennis amplified the wave" as it traveled northward, Morey said.

Rare setup

Though trapped waves are common and have been understood for years, "this is the first time it's made a difference in the hurricane storm surge," Morey said.

Storm surge forms in just a few hours as a hurricane approaches land, when its winds directly drive the water onshore. A trapped wave takes at least a day or longer to form.

Dennis was a special case that combined these two phenomena because the hurricane was barreling towards the northern Gulf Coast, with the Florida coast on its right. Timing, however, was the crucial element, because the hurricane brushed the shore just as the trapped wave arrived, amplifying the normal storm surge.

"They just added together," Morey said.

This type of trapped wave could play a part in future storms that travel a path similar to Dennis's or along the Louisiana coastline heading towards Texas. National Hurricane Center forecasters plan to factor this phenomenon into their forecasting models so they can better predict storm surge levels.

The research was reported earlier this month in the journal Geophysical Research Letters .

The Marseille attack left a 26-year-old woman with burns to most of her body.

France has seen a recent rise in such attacks, a year after a wave of rioting rocked its impoverished suburbs.

Gangs of youths, many of them of immigrant descent, torched cars and clashed with police during three weeks of unrest last year.

Factors 'unchanged'

Earlier on Monday, the French government held an emergency meeting on transport security.

Mr de Villepin appealed for witnesses to the Marseille attack and Interior Minister Nicolas Sarkozy said the perpetrators would be tracked down and punished. About 200 extra police were deployed in the city.

A group of teenagers reportedly forced open the doors of the bus vehicle and threw a flammable liquid inside before fleeing.

A 26-year-old French woman of Senegalese origin was unable to escape and suffered burns to 70% of her body.

About 200 vehicles were set alight in incidents around the country on Saturday, and nearly 50 people were arrested.

French news agency AFP said youths in Grenoble threw a stone from a bridge onto a tram, smashing the window and injuring the driver.

Last year's riots were sparked by the deaths of two teenagers in a suburb of Paris. There is dispute over whether they were chased by police before they were electrocuted while hiding in an electricity sub-station.

During the violence last year, more than 10,000 cars were set ablaze and 300 buildings firebombed.

Community leaders in run-down French suburbs have warned that the factors which played a key part in the riots - high unemployment, racial discrimination and alienation from mainstream society - remain unchanged.

All the incidents took place on Friday evening, one of the busiest nights of the week for emergency crews, he added.

Discharged

"Taking three ambulances out of the system on a Friday could potentially be a problem", said Mr Ware.

A woman in her twenties was discharged from the Lister Hospital in Stevenage after being treated.

And the two other cinemagoers - who had been at the town's Cineworld complex - were left "in the care of friends and relatives" without needing to be taken to hospital.

A man aged 34 fainted at the Showcase in Peterborough, Mr Ware said.

There was also a case of a 22-year-old woman passing out at Cineworld in Cambridge on Friday, but it had not been confirmed that she was watching Saw III, he added.

The slasher movie - currently number one at the North American box office - was released last week in the UK.

A spokeswoman for the Cineworld chain said they did not wish to comment.