CAT Models Miss Hidden Gas Terror: Benfield

The alarm is being sounded by Benfield Hazard Research Centre at University College London, in a report on potential greenhouse effects if the earth's huge deposits of gas hydrates begin to thaw.

Consisting of frozen mixes of mostly methane gas and water, the hydrates up to now have generally been kept stable in ocean sediment and permafrost regions by low temperatures and high pressure, the report said.

But according to Benfield, climate models for global warming predict the intermediate ocean depths will heat up and destabilize the hydrates resulting in an explosive release of large quantities of methane that spark a vicious cycle accelerating the warming process.

Release of methane, a greenhouse gas 21 times more powerful than carbon dioxide "could lead to more oceanic warming, more methane release and ever increasing warming," the report noted.

Whether a natural catastrophe results from the warming depends on whether the heat effect exceeds the countering effect of rising sea level," Benfield said.

The report said there is "good evidence" that gas hydrate decomposition has triggered massive submarine sediment earth slides in the past. Discussing what could occur if the exploding gas starts busting loose, Benfield researcher Mark Maslin, who authored the report, pointed to the Storegga slide off Norway 7,000 years ago.

The resulting event, when a territory the size of Wales slipped into the sea, created a tsunami that "wiped out Northern Scotland," said Dr. Maslin.

While most of the hydrates are located in high latitude sparsely populated areas of Northern Europe, Russia and Canada, the effects of a slide could send a tidal wave thrashing about the North Atlantic, said Dr. Maslin.

Unlike the Pacific Coast, which has a tsunami warning system in place, "there's nothing like that for Western Europe or the East Coast of the U.S" and a 15 meter high tsunami "could do a lot of damage to New York"

Dr. Maslin said that current CAT models do not account for possible hydrate effects because the research in the area was only done in the last two to five years, and while it was mentioned is not included in the global warming prediction by the Intergovernmental Panel on Climate Change.

"We know they [hydrates] exist. We have drilled into them," but how much there is on the planet, he said, is a subject of discussion much like the extent of the world's oil reserves.

"We're still trying to get a feel for what's there and what's going to be released" Dr. Maslin remarked and "Most science suggests in a warmer world they will start to break down."

Besides slides and tsunamis, the report said that methane releases in relatively shallow water could cause the collapse of oil and gas platforms by destabilizing the sediment they stand on.

Benfield also said there was a remote possibility that methane release could create negative buoyancy in shallow waters and cause ships to sink–a theory advanced as a possible cause for the loss of vessels in the ?Bermuda Triangle.'

The firm's report said there was also a slim chance that methane explosively released from permafrost areas "in the right circumstances would burn posing a serious, if highly localized hazard."