Global Warming "Marches On"; Past Decade Hottest Known

The past decade has been the hottest on record, according to new global warming data released today at the Copenhagen climate conference by the World Meteorological Organization.

What's more, 2009 is shaping up to be the fifth warmest year since coordinated record keeping began in 1850, according to preliminary figures released by the Geneva-based UN organization. The final report, including December climate data, will be released in March 2010.

The new data, collected from land-based weather stations across the world, as well as by ships, buoys, and satellites, does not show a slowdown or reversal of the global warming trend, Michel Jarraud, secretary general of the World Meteorological Organization (WMO), said at a press briefing.

Peter Stott, climate scientist with the Met Office, the U.K.'s national weather service, said in an interview, "The latest data shows how the underlying march of global warming goes on."

The findings fit with numerous studies supporting a long-term global warming trend.

Global warming research has been criticized in recent weeks in the wake of leaked emails from the U.K.'s University of East Anglia, which provided some of the new climate data. The private, "Climategate" email exchanges among climate scientists refer to statistical "tricks" used to support a case for global warming and, to some, suggest a stifling of data that runs contrary to global warming findings.

Questioned about the role of the University of East Anglia, the WMO's Jarraud argued that the new climate data has been verified by two further independently gathered data sets from the U.S. National Oceanic and Atmospheric Administration and NASA's Goddard Institute for Space Studies.

Extreme Weather Due to Climate Change?

The climate research revealed today in Copenhagen says that that global combined air surface and sea surface temperatures for 2009 have so far hit 14.44°C (57.99°F). This is 0.44°C (0.79°F) above the average annual temperature of 14.00°C (57.20°F) recorded between 1961 and 1990, which is used as a reference period, according to the WMO.

Most of the world's continents experienced above-average temperatures this year, with the exception of North America, which cooled down.

(Related: "Global Warming Could Cool North America in a Few Decades?")

Many other regions, including parts of South Asia, China, and Africa, experienced their highest temperatures on record.There were also a number of extreme weather events, Jarraud added, including unprecedented heat waves in India, parts of Europe, and Australia. (See a world map of potential global warming impacts.) Australia experienced its third hottest year on record, and faced three heat waves of remarkable intensity.

This included one in February, labeled Black Saturday, which encouraged 400 wildfires that swept across the state of Victoria, killing 173 people and destroying 3,500 buildings. (See pictures of the Australian fires.)

Other extreme weather events of 2009 included the deadliest typhoon ever known to have hit Taiwan, which left 461 people dead in August, and flooding in the West African country of Burkina Faso, which displaced 150,000.

2009 Temperatures "Frightening"

Jarraud emphasized that temperature trends can vary over time.

"The warming is not uniform—there will still be cold winters, there will be cold summers. What we are talking about here is the trend over large areas and over long periods," he said.

"What will happen is that the cold periods will be become less frequent and the heat waves will become more frequent and more intense."

Andy Pitman, of the Climate Change Research Centre at the University of New South Wales in Sydney, Australia, agreed that the findings are significant.

"Given we are in a period of low solar activity, and have been through a sustained La Niña, 2009 should have been a cool year," Pitman said.

"The fact it ranked in the top five since 1850 is actually frightening."