Geneva, 8 December 2009 (WMO) – 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 and 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.
Final updates and figures for 2009 will be published in March 2010 in the annual WMO Statement on the Status of the Global Climate.
Regional temperature anomalies
The year 2009 (January–October) was again warmer than the 1961–1990 average all over Europe and the Middle East. China had the third-warmest year since 1951; for some regions 2009 was the warmest year. The year started with a mild January in northern Europe and large parts of Asia, while western and central Europe were colder than normal. Russia and the Great Lakes region in Canada experienced colder-than- average temperatures in February and January, respectively. Spring was very warm in Europe and Asia; April in particular was extremely warm in central Europe. Germany, the Czech Republic and Austria reported temperature anomalies of more than +5°C, breaking the previous records for the month in several locations. The European summer was also warmer than the long-term average, particularly over the southern regions. Spain had the third-warmest summer, with hotter summers reported only in 2003 and 2005. Italy recorded a strong heatwave in July, with maximum temperatures above 40°C, and some local temperatures reaching 45°C. A heatwave at the beginning of July affected the United Kingdom, France, Belgium and Germany, and some stations in Norway experienced new maximum temperature records.
India had an extreme heatwave event during May, which caused 150 deaths. A heatwave hit northern China during June, with daily maximum temperatures above 40°C; historical maximum temperature records were broken for the summer in some locations.
In late July many cities across Canada recorded their warmest daily temperatures. Vancouver and Victoria set new records, reaching 34.4°C and 35.0°C, respectively. Alaska also had the second-warmest July on record. Conversely, October was a very cold month across large parts of the United States. For the nation as a whole, it was the third-coolest October on record, with an average temperature anomaly of -2.2°C (-4.0°F). Similarly, a very cold October was reported in Scandinavia, with mean temperature anomalies ranging from -2°C to -4°C.
The austral autumn (March to May) was extremely warm in Argentina, Uruguay, Paraguay and southern Brazil. With daily temperatures ranging from 30°C to 40°C, several records were broken during this season. By the end of October, an extreme weather situation affected north and central Argentina, producing unusually high temperatures (above 40°C). Conversely, November was abnormally cold in the southern part of the region, with some rare and late snowfalls.
So far, Australia has had the third-warmest year on record. The year 2009 was marked by three exceptional heatwaves, which affected south-eastern Australia in January/February and November, and subtropical eastern Australia in August. The January/February heatwave was associated with disastrous bushfires that caused more than 173 fatalities. Victoria recorded its highest temperature with 48.8°C. The northern region experienced a cold summer, however, with anomalies reaching -3°C to -4°C in some places. Winter was exceptionally mild over much of Australia. Maximum temperatures were well above normal across the entire continent, reaching 6°C to 7°C above normal in some parts. The national maximum temperature anomaly of +3.2°C was the largest ever recorded for any month.
read the full report here