Decade of 2000s was Warmest Ever 12/7/09 & 12/8/09
| Marilyn Sigman, Alaska SeaGrant/MAP
Tags: Climate Change, Changing Arctic Sea Ice
Decade of 2000s was warmest ever, scientists say
By CHARLES J. HANLEY, AP Special Correspondent 12/7/09
Over the decade's first nine years, global temperatures averaged 0.6 degrees Celsius (1.1 degrees F) higher than the 1951-1980 average, NASA reported. And temperatures rose faster in the far north than anyplace else on Earth.
The decade's final three summers melted Arctic sea ice more than ever before in modern times. Greenland's gargantuan ice cap was pouring 3 percent more meltwater into the sea each year. Every summer's thaw reached deeper into the Arctic permafrost, threatening to unlock vast amounts of methane, a global-warming gas.
Less ice meant less sunlight reflected, more heat absorbed by the Earth. More methane escaping the tundra meant more warming, more thawing, more methane released.
At the bottom of the world, late in the decade, International Polar Year research found that Antarctica, too, was warming. Floating ice shelves fringing its coast weakened, some breaking away, allowing the glaciers behind them to push ice faster into the rising oceans.
On six continents the glaciers retreated through the 2000s, shrinking future water sources for countless millions of Indians, Chinese, South Americans. The great lakes of Africa were shrinking, too, from higher temperatures, evaporation and drought. Across the temperate zones, flowers bloomed earlier, lakes froze later, bark beetles bored their destructive way northward through warmer forests. In the Arctic, surprised Eskimos spotted the red breasts of southern robins.
In the 2000s, all this was happening faster than anticipated, scientists said. So were other things: By late in the decade, global emissions of carbon dioxide matched the worst case among seven scenarios laid down in 2001 by the Intergovernmental Panel on Climate Change, the U.N. scientific network formed to peer into climate's future. Almost 29 billion tons of the gas poured skyward annually — 23 percent higher than at the decade's start.
By year-end 2008, the 2000s already included eight of the 10 warmest years on record. By 2060, that trajectory could push temperatures a dangerous 4 degrees C (7 degrees F) or more higher than preindustrial levels, British scientists said.
Charles J. Hanley has covered climate issues for The Associated Press since the Kyoto conference of 1997. Meterological Organization Press Release
2000-2009 The Warmest Decade
World Meteorological Society Press Release 12/8/09
The year 2009 is likely to rank in the top 10 warmest on record since the beginning of instrumental climate records in 1850, according to data sources compiled by the World Meteorological Organization (WMO). The global combined sea surface nd land surface air temperature for 2009 (January–October) is currently estimated at 0.44°C ± 0.11°C (0.79°F ± 0.20°F). above the 1961–1990 annual average of 14.00°C/57.2°F. The current nominal ranking of 2009, which does not account for uncertainties in the annual averages, places it as the fifth-warmest year. The decade of the 2000s (2000–2009) was warmer than the decade spanning the 1990s (1990–1999), which in turn was warmer than the 1980s (1980–1989). More complete data for the remainder of the year 2009 will be analysed at the beginning of 2010 to update the current assessment.
This year above-normal temperatures were recorded in most parts of the continents. Only North America (United States and Canada) experienced conditions that were cooler than average. Given the current figures, large parts of southern Asia and central Africa are likely to have the warmest year on record.
Climate extremes, including devastating floods, severe droughts, snowstorms, heatwaves and cold waves, were recorded in many parts of the world. This year the extreme warm events were more frequent and intense in southern South America, Australia and southern Asia, in particular. La Niña conditions shifted into a warm-phase El Niño-Southern Oscillation (ENSO) in June. The Arctic sea ice extent during the melt season ranked the third lowest, after the lowest and second-lowest records set in 2007 and 2008, respectively.
This preliminary information for 2009 is based on climate data from networks of land-based weather and climate stations, ships and buoys, as well as satellites. The data are continuously collected and disseminated by the National Meteorological and Hydrological Services (NMHSs) of the 189 Members of WMO and several collaborating research institutions. The data continuously feed three main depository global climate data and analysis centres, which develop and maintain homogeneous global climate datasets based on peer-reviewed methodologies.
The WMO global temperature analysis is thus based on three complementary datasets. One is the combined dataset maintained by both the Hadley Centre of the UK Met Office and the Climatic Research Unit, University of East Anglia, United Kingdom. Another dataset is maintained by the National Oceanic and Atmospheric Administration (NOAA) under the United States Department of Commerce, and the third one is from the Goddard Institute of Space Studies (GISS) operated by the National Aeronautics and Space Administration (NASA). The content of the WMO statement is verified and peer-reviewed by leading experts from other international, regional and national climate institutions and centres before its publication.