On the Puerto Rican island of Vieques, members of the Woods Hole research team collected sediments left by hurricanes of earlier times.
By ANDREW C. REVKIN
Published: May 24, 2007
Over the last 5,000 years, the eastern Caribbean has experienced several periods, lasting centuries, in which strong hurricanes occurred frequently even though ocean temperatures were cooler than those measured today, according to a new study.
The authors, from the Woods Hole Oceanographic Institution, say their findings do not necessarily conflict with recent papers asserting a link between the region’s hurricane activity and human-caused warming of the climate and seas.
But, they say, their work does imply that factors other than ocean temperature, at least for thousands of years, appear to have played a pivotal role in shaping storminess in the region.
The study compared a 5,000-year record of strong storms etched in lagoon mud on the Puerto Rican island of Vieques with data on ocean temperatures and climate and storm patterns. The analysis is being published today in the journal Nature.
The Woods Hole team found that stormier spans, including one from 1700 until now, were associated with a relative paucity of El Niño warm-ups of the tropical Pacific Ocean and also with periods of heightened monsoon intensity in West Africa.
El Niño episodes tend to change wind patterns in ways that weaken Atlantic Ocean hurricanes, and Africa is a nursery for storm fronts that can drift westward and develop into hurricanes.
Storm records extracted from sediments on the Gulf Coast by other scientists, and near New York City by the Woods Hole team, show a similar pattern, implying that the shifts from quieter to stormier times are not just a local phenomenon, the authors said.
Jeffrey P. Donnelly, the lead author, said the findings pointed to the importance of figuring out an unresolved puzzle: whether global warming will affect the Niño cycle one way or the other. More intense or longer Pacific warm-ups could stifle Atlantic and Caribbean hurricanes even with warmer seas, Dr. Donnelly said.
“Warm sea-surface temperatures are clearly the fuel for intense hurricanes,” he said. “What our work says is that without sea temperatures varying a lot, the climate system can flip back and forth between active and inactive regimes.”
He added that a disturbing possibility was a warming of waters while conditions in the Pacific and Africa are in their hurricane-nurturing mode.
“If you flip that knob and also have warming seas,” Dr. Donnelly said, “oh boy, who knows what could happen?”
Judith A. Curry, an atmospheric scientist at Georgia Tech, said the new study, together with other recent research on warming and storms by her and others, added to a picture of rising risk and lagging government action on reducing vulnerability of coastal populations in the Atlantic and Caribbean hurricane zone.
“The bottom line is that we are in an unusually active period of hurricane activity, as a result of a combination of natural variability and global warming,” Dr. Curry said. “Analyses have been done, plans have been put on the table, but nothing seems to be happening.”
Environment News Service: Up to Five Major Atlantic Hurricanes Forecast for 2007
WASHINGTON, DC, May 23, 2007 (ENS) - Sea surface temperatures in the Pacific Ocean are cooling while Atlantic temperatures are warming - a climate recipe for an Atlantic hurricane season more active than normal, according to government scientists.
Just before the official hurricane season starts June 1, hurricane experts at the Climate Prediction Center operated by the National Oceanic and Atmospheric Administration, NOAA, said Tuesday there is a 75 percent chance that the Atlantic hurricane season will be above normal this year.
"For the 2007 Atlantic hurricane season, NOAA scientists predict 13 to 17 named storms, with seven to 10 becoming hurricanes, of which three to five could become major hurricanes of Category 3 strength or higher," said NOAA Administrator Conrad Lautenbacher.
Major Category 3 storms as rated on the Saffir-Simpson Scale bring sustained winds of 111 to 130 miles per hour. Category 4 storms bring winds of 131-155 mph, and Category 5 storms, the highest on the scale, pack winds greater than 155 mph.
An average Atlantic hurricane season brings 11 named storms, with six becoming hurricanes, including two major hurricanes.
At a news conference Tuesday at Reagan National Airport, officials from NOAA, the Air Force Reserve and the U.S. Coast Guard, stood with Federal Emergency Management Agency, FEMA, Administrator David Paulison, and Homeland Security Secretary Michael Chertoff to announce the updated forcast. The officials emphasized their commitment to federal agency teamwork as the hurricane season approaches.
Chertoff said the federal government is prepared to respond with a set of tools never before assembled - new communication equipment, more ready supplies in place, and the ability to more rapidly register and track potentially displaced storm victims.
Climate patterns responsible for the expected 2007 hurricane activity continue to be the ongoing multi-decadal signal - the set of ocean and atmospheric conditions that spawn increased Atlantic hurricane activity, as well as warmer than normal sea surface temperatures in the Atlantic Ocean, and the El Niño/La Niña cycle in the Pacific.
Last year, seasonal hurricane predictions proved to be too high when an unexpected El Niño rapidly developed and created a hostile environment for Atlantic storms to form and strengthen. When storms did develop, steering currents kept most of them over the open water and away from land.
Historically, the next couple of months are a critical time period for the possible emergence of La Niña.
"There is some uncertainty this year as to whether or not La Niña will form, and if it does how strong it will be," said Gerry Bell, PhD, lead seasonal hurricane forecaster at the NOAA Climate Prediction Center.
"The Climate Prediction Center is indicating that La Niña could form in the next one to three months. If La Niña develops, storm activity will likely be in the upper end of the predicted range, or perhaps even higher depending on how strong La Niña becomes."
Bell says that even if La Niña does not develop, the conditions associated with the ongoing active hurricane era still favor an above-normal season."
The NOAA forecast is in line with another closely watched forecast issued by the Colorado State University hurricane forecast team on April 3.
The Colorado State team of Bill Gray and Phil Klotzbach forecast that 17 named storms would form in the Atlantic basin between June 1 and November 30, when the official hurricane season ends.
Nine of the 17 storms are predicted to become hurricanes, and of those nine, five are expected to develop into intense or major hurricanes above Category 3, the Colorado team said.
"We are calling for a very active hurricane season this year, but not as active as the 2004 and 2005 seasons," said Klotzbach. "Based on our latest forecast, the probability of a major hurricane making landfall along the U.S. coastline is 74 percent compared with the last-century average of 52 percent.
The Colorado team projects a 50 percent chance that a major hurricane will make landfall on the U.S. East Coast, including the Florida Peninsula. By comparison, the long-term average is 31 percent.
They say there is a 49 percent chance that a major hurricane will make landfall on the Gulf Coast from the Florida Panhandle west to Brownsville, Texas. The long-term average is 30 percent.
The Colorado team also predicted an above-average major hurricane landfall risk in the Caribbean this season.
"With expectations for an active season, it is critically important that people who live in East and Gulf coastal areas as well as the Caribbean be prepared," said Bill Proenza, NOAA National Hurricane Center director. "Now is the time to update your hurricane plan, not when the storm is bearing down on you."
Secretary Chertoff also stressed the importance of preparedness. "It is an individual responsibility," he said.
Paulison encouraged citizens of storm prone areas to prepare a disaster kit. Residents should have a supply of non-perishable food and water to sustain their family for at least 72 hours, he said. The kits should also include first-aid supplies, prescription medicines and other important personal items.
Residents should have an evacuation plan, and be prepared to deal with pets in case evacuation is necessary.
The Atlantic hurricane season runs from June 1 through November 30, with peak activity occurring August through October.
The Atlantic Hurricane Seasonal Outlook is an official forecast product of the NOAA Climate Prediction Center. The Center will issue an updated seasonal forecast in August just before the historical peak of the season.
Reuters: Malaysia on PR Campaign over Rainforests, Wildlife MALAYSIA: May 24, 2007
TANJONG MALIM, Malaysia - Malaysia's palm oil industry, stung by global criticism over the environmental impact of rapidly expanding plantations, has launched a campaign to tell the world that it cares for forests and wildlife.
The world's largest plantation company, Synergy Drive, which is being formed through the merger of three state-run businesses, is leading the way, as a consumer backlash against palm oil could spell the end of booming demand for the product.
"We big plantations have always been accused of not looking after the rainforests," said Synergy Drive chief executive Ahmad Zubir Murshid, who spent a day last weekend trying to convince journalists of the firm's green credentials.
"What we are going to do is create sanctuaries of animals and birds so that they can co-exist with our plantations."
The industry-funded Malaysian Palm Oil Council has also chimed in, saying the nation has committed 20 million ringgit (US$5.91 million) for conservation of wildlife, including the orangutans.
But conservationists are not entirely convinced, pointing out the industry has taken years to realise the damage it has done.
Friends of the Earth says almost 90 percent of the orangutan habitat has now disappeared and if the destruction continues, Asia's only great ape could become extinct in 12 years.
With palm oil prices up nearly 68 percent since January, 2006, plantations now cover about 4 million hectares in Malaysia, and firms are expanding fast into neighbouring Indonesia where they had 889,354 hectares in 2006.
Palm oil is used in a wide variety of products ranging from cooking to fuel oils.
Greenpeace says Indonesia had the fastest pace of deforestation in the world between 2000-2005, with an area of forest equivalent to 300 soccer pitches destroyed every hour.
Friends of the Earth questions U.K. supermarkets selling palm oil on their corporate social responsibility and has urged financiers screen future investments in plantations for adverse environmental affects.
This aggressive campaign by green groups is having its impact and palm producers are feeling the heat.
The Netherlands plans a certification system for the use of biomass materials, such as grains, sugars and vegetable oils, to guarantee their sustainability.
"Direct burning of palm oil for power generation in Europe has reduced by 50 percent mainly because of environmental concerns," said M. R. Chandran, an independent analyst and a former head of Malaysian Palm Oil Association.
Malaysia's plantation industry, which says the nation has 64 percent forest cover, is pushing its campaign and working with groups like WWF. "We are trying to get them to voluntarily give back to nature, by allocating some of the lands to build forest corridors for animals," said Dionysius Sharma, executive Director, WWF-Malaysia.
Diversified Sime Darby, which is being merged with Golden Hope and Kumpulan Guthrie, plans to plant millions of trees in a 400-hectare heritage park in northern Perak state with some rare rainforest varieties.
It has engaged a nursery that specialises in rare rainforest species. "We had some 3,000 species trees on peninsular Malaysia, but some of these are difficult to find," said James Kingham, who runs the nursery near Tanjong Malim, 100 km (62 miles) north of Kuala Lumpur.
Kingam showed, as he toured his 28-hectare nursery, a rare variety of wild lychee which at one time grew all over Malaysia. (Additional reporting by Niluksi Koswanage)