UN weather agency says La Nina climate pattern weakening

Yahoo News 17 Feb 09;

GENEVA (AFP) – La Nina, the weather phenomenon that has been blamed for icy conditions that claimed dozens of lives across Europe since November, is weakening, the World Meteorological Organization said Tuesday.

La Nina is produced by cooler surface water temperatures in the Pacific Ocean and, like its Pacific sibling El Nino, is credited with upsetting climate patterns around the world.

"As these conditions weaken, the outlook for March-May 2009 is for 'neutral' conditions to be the most likely outcome," the UN's weather agency said in a statement.

However, forecasts for the remainder of this year were "very uncertain" at the moment, the statement added.

The average global temperature for 2008 was slightly lower than any other year since 2000, due partly to La Nina, according to the WMO.

In December, "unusually cold" sea-surface temperatures, or over 0.5 degrees Celsius (32.9 degrees Fahrenheit) below normal temperatures, were recorded in the central and eastern equatorial Pacific.

In 2007, the WMO linked the La Nina climate pattern to a long-running drought in Australia.

Cooler Pacific To Normalize In Coming Months: WMO
Laura MacInnis, PlanetArk 18 Feb 09;

GENEVA - Cooler than usual Pacific sea-surface temperatures should return to normal in the coming months, and no major La Nina or El Nino events are expected, the World Meteorological Organization (WMO) said on Tuesday.

The United Nations weather agency said that the tropical Pacific Ocean saw temperatures 0.5 degrees Celsius below normal in December, and was now regularizing. La Nina weather results in cooler-than-normal waters in the Pacific Ocean and is believed to spur hurricane formation in the Atlantic basin.

"La Nina-like conditions will most likely dissipate over the next couple of months, returning the tropical Pacific to neutral conditions by March-May 2009," the WMO said in its latest quarterly report.

For the first half of this year, it found that "the likelihood of El Nino conditions developing is no higher than that of La Nina conditions."

The El Nino weather phenomenon results in warmer-than-normal Pacific waters that can wreak havoc in weather patterns. The most devastating was in 1997/98 when it caused major drought in Australia and Indonesia and spawned floods in Peru and Ecuador.

(Editing by Louise Ireland)