ScienceDaily (Apr. 19, 2008) — Hurricanes in some areas, including the North Atlantic, are likely to become more intense as a result of global warming even though the number of such storms worldwide may decline, according to a new study by MIT researchers.
Kerry Emanuel, the lead author of the new study, wrote a paper in 2005 reporting an apparent link between a warming climate and an increase in hurricane intensity. That paper attracted worldwide attention because it was published in Nature just three weeks before Hurricane Katrina slammed into New Orleans.
Emanuel, a professor of atmospheric science in MIT's Department of Earth, Atmospheric and Planetary Sciences, says the new research provides an independent validation of the earlier results, using a completely different approach. The paper was co-authored by postdoctoral fellow Ragoth Sundararajan and graduate student John Williams and recently appeared in the Bulletin of the American Meteorological Society.
While the earlier study was based entirely on historical records of past hurricanes, showing nearly a doubling in the intensity of Atlantic storms over the last 30 years, the new work is purely theoretical. It made use of a new technique to add finer-scale detail to computer simulations called Global Circulation Models, which are the basis for most projections of future climate change.
"It strongly confirms, independently, the results in the Nature paper," Emanuel said. "This is a completely independent analysis and comes up with very consistent results."
Worldwide, both methods show an increase in the intensity and duration of tropical cyclones, the generic name for what are known as hurricanes in the North Atlantic. But the new work shows no clear change in the overall numbers of such storms when run on future climates predicted using global climate models.
However, Emanuel says, the new work also raises some questions that remain to be understood. When projected into the future, the model shows a continuing increase in power, "but a lot less than the factor of two that we've already seen" he says. "So we have a paradox that remains to be explained."
There are several possibilities, Emanuel says. "The last 25 years' increase may have little to do with global warming, or the models may have missed something about how nature responds to the increase in carbon dioxide."
Another possibility is that the recent hurricane increase is related to the fast pace of increase in temperature. The computer models in this study, he explains, show what happens after the atmosphere has stabilized at new, much higher CO2 concentrations. "That's very different from the process now, when it's rapidly changing," he says.
In the many different computer runs with different models and different conditions, "the fact is, the results are all over the place," Emanuel says. But that doesn't mean that one can't learn from them. And there is one conclusion that's clearly not consistent with these results, he said: "The idea that there is no connection between hurricanes and global warming, that's not supported," he says.
Talking about huge waves... Here is one hitting a cruise ship and catching the bridge crew a little off guard.
From Storm Reports '08 tornado losses top $1 billion, report finds '
Palm Beach Post Staff Writer
Monday, April 21, 2008
This year has been a tough one for people living in areas hit by tornadoes.
It hasn't been good for insurers there, either.
Insured losses from tornadoes have passed the $1 billion mark this year, according to a new report from A.M. Best, the influential insurance and financial services rating company.
About $850 million of that came from the Super Tuesday outbreak that killed 55 people in the mid-South on Feb. 5-6.
The first-quarter losses surpassed the previous four-year average, said Oldwick, N.J.-based A.M. Best.
Until recently, insurers have taken comfort in the fact that tornado damage historically has not been as severe as that of major hurricanes.
"But according to data from catastrophe modeling firms, these events have the potential - with the right conditions - to generate insured losses on par with hurricanes, such as 2004's Hurricane Frances and 2005's Hurricane Rita," the report said.
States that recently endured severe tornadoes - including Georgia, Tennessee, Missouri, Kentucky, Alabama, South Carolina, Mississippi and Arkansas - may see increased premiums, deductibles and coverage interruptions, A.M. Best said.
Even more troubling, the firm said a new trend has emerged in the last several years: Losses of $1 billion and more from single-event tornadoes are more common.
If tornado-favoring weather patterns continue, insurers could feel more of a struggle to remain profitable, particularly smaller companies that write policies in single states, the rating service said.
- Randy Diamond
Shipping industry is ‘courting disaster’
The container shipping industry is sacrificing safety and risking an environmental disaster to reduce costs and meet tight delivery schedules, according to an investigation into the grounding of a ship off the coast of Devon last year.
Another 22 ships have been found to have design flaws similar to those of the MSC Napoli, which was deliberately grounded a mile off Sidmouth after her hull cracked in heavy seas.
The Marine Accident Investigation Branch (MAIB) found that the ship was carrying many overloaded containers and had been travelling too fast for the conditions.
After the incident hundreds of people flocked to Branscombe beach to scavenge everything from BMW motorcycles to disposable nappies when dozens of containers washed ashore.
The Napoli, built in 1991 in South Korea, was in the Channel on passage to Portugal from Antwerp when her engine room flooded after a hull failure about 45 miles south of Lizard Point, Cornwall.
The MAIB report, published today, says that after the Napoli hit “several large waves” there was a “large crashing or cracking sound”.
Vertical cracks could be seen in the hull below the waterline on the port and starboard sides, and the ship’s master assessed that the vessel had “broken her back”.
The crew of 26 abandoned ship and were rescued by two Royal Navy helicopters. Tugs began towing the ship towards Portland in Dorset but she was beached en route because there were concerns that she might sink.
The beaching prevented severe oil pollution of Devon and Dorset’s World Heritage Coast.
The MAIB said that a review of safety rules governing container ship design and a code of practice covering operations was urgently needed to prevent further losses.
It concluded that the container shipping industry had been allowed to expand rapidly — from 12 million to 140 million containers a year since 1983 — without proper safety oversight.
The report said: “The commercial advantages of containerisation . . . such as speed and quick turnarounds appear to have become the focus of the industry at the expense of the safe operation of its vessels.”
The MAIB found that a loophole in safety regulations meant that the buckling strength of the hull near the engine room had not been tested.
It also found that ship’s loading contributed to the stresses on the hull. The MAIB condemned the widespread practice in the industry of failing to load containers, either to save time or avoid taxes.
“Container shipping is the only sector of the industry in which the weight of a cargo is not known.”
The MAIB referred to a previous report, which it published last September on the collapse of cargo containers on the Annabella, which concluded: “Evidence obtained during this and other MAIB investigations into container shipping accidents suggests that in reality, the safety of ships, crews and the environment is being compromised by the overriding desire to maintain established schedules or optimise port turn-round times.”
After the Napoli grounding the MAIB ordered the screening of more than 1,500 container ships, and 12 were identified as being potentially vulnerable to buckling in severe conditions and requiring remedial action. A further ten vessels were identified as being borderline and needing more detailed investigation. The screening of eight container ships has yet to be completed.
The International Chamber of Shipping is developing a code of best practice for the industry, which is expected to be completed by the end of the year.
The report said that Britain would conduct a “concentrated inspection campaign” in 2010 to check compliance with tightened safety rules.
A Devon County Council local public inquiry into the grounding of the Napoli will be chaired by Ian Mercer, an environmental specialist. “This inquiry must seek all the answers available, and register with governments the outstanding questions,” Professor Mercer said.
The inquiry’s evidence-gathering process, which was launched last month, was the first stage of the investigation, which will be followed by hearings in public.
Report on the investigation of the structural failure of MSC Napoli in the English Channel on 18 January 2007.
Report No 9/2008
Published 22 April 2008
FROM THE LEGAL BEAGLES AT HOLLAND AND KNIGHT
The UK Marine Accident Investigation Branch (MAIB) released the report of its investigation of the structural failure of the container ship MSC NAPOLI in the English Channel on 18 January 2007. The report found that the ship’s hull did not have sufficient buckling strength in way of the engine room; that there was an insufficient safety margin between the hull’s design loading and its ultimate strength; and that the load on the hull was increased by whipping effect. Recommendations have been made to the International Association of Classification Societies (IACS) that are intended to increase the requirements for container ship design, consolidate current research into whipping effect, and to initiate research into the development and use of technological aids for measuring hull stresses. As ships get larger, simple extrapolation is insufficient. Report No. 9/2008 (4/22/08).