Related News:
Pacific Ocean Likely in Early Stages of La Nina, Australian Bureau Says
The Pacific Ocean is likely in the early stages of a La Nina cycle that may mean more Atlantic hurricanes and drier, warmer winters across the southern U.S.
Some parts of the Pacific near the equator are now 1 degree Celsius (1.8 degrees Fahrenheit) below average, the Australia’s Bureau of Meteorology said on its website today.
“As computer models predict the central Pacific will continue to cool over the coming months, it is now highly likely that the Pacific is in the early stages of a La Nina event, and that 2010 will be considered a La Nina year,” the bureau said.
La Nina is a cooling of the equatorial Pacific Ocean occurring on average every three to five years and lasting nine to 12 months, according to the U.S. National Oceanic and Atmospheric Administration. Some events have lasted as long as two years.
La Ninas enhance the conditions necessary for hurricanes to develop in the Atlantic by damping high-altitude winds that can tear the storms apart as they are forming, according to the U.S. National Hurricane Center in Miami.
An increase in the number of hurricanes boosts the chances that a storm will enter the Gulf of Mexico, home to about 30 percent of U.S. oil and 12 percent of U.S. natural gas production, Energy Department data show.
Replaces Warming
The cooling replaces a warming event, or El Nino, that took place last year and is credited in part with making the 2009 Atlantic hurricane season one of the least-active since 1997.
The switch has caused forecasters to predict an above- average number of storms in the Atlantic this year.
Yesterday, WSI Corp., an Andover, Massachusetts-based weather software maker, called for 19 named storms to form in the Atlantic this year. While the company had earlier forecast 20 storms, a pocket of dry air over the Atlantic has retarded storm growth, said Todd Crawford, WSI’s chief meteorologist.
“We still expect an extremely active August-October period,” Crawford said in a statement.
A storm gets a name when its sustained winds reach 39 miles per hour, according to the hurricane center.
La Nina’s cooling patterns often bring drier, warmer weather to the southern half of the U.S., increasing wildfire threats in Florida and California. Florida is the second-largest producer of oranges, behind Brazil.
Market Impact
The phenomenon may also affect oil and natural gas markets during the U.S. winter, said Travis Hartman, a meteorologist at MDA Federal Inc.’s EarthSat Energy Weather in Rockville, Maryland.
“Historically, strong La Ninas have produced mild winters in the East while relatively weak La Ninas have favored colder temperatures in the Midwest and East,” Hartman said.
Increased rainfall in southern Africa, northeastern South America and the U.S. Pacific Northwest are also common during La Ninas, according to NOAA.
To contact the reporters on this story: Brian K. Sullivan in Boston at bsullivan10@bloomberg.net; Wendy Pugh in Melbourne at wpugh@bloomberg.net
Rate These Stories
Rate this Page