The warmest year on record is a three-way tie- 2010, 2005 and 1998.
So says the U.N. weather agency, providing further evidence on Thursday that the planet is slowly but surely heating up.
Average temperatures globally last year were 0.53 Celsius higher than the 1961-90 mean that is used for comparison purposes, according to World Meteorological Organisation.
That's a bit lower than what the U.S. National Climatic Data Center announced earlier this month, but the World Meteorological Organisation also uses figures based on data collected by Britain's Meteorological Office and NASA.
“The 2010 data confirm the Earth's significant long-term warming trend,” said Michel Jarraud, WMO's top official. He added that the ten warmest years after records began in 1854 have all occurred since 1998.
The average worldwide temperature for the 20th century was 13.88 degrees Celsius.
But rising global temperatures over the last century are causing climate experts to worry. Most atmospheric scientists attribute the change to carbon dioxide and gases released into the air by gasoline-burning engines and other industrial processes. The gases tend to trap heat in the atmosphere like a greenhouse.
The Geneva-based global weather agency noted that last year's extreme weather — notably the heat wave in Russia and monsoon flooding in Pakistan — has continued into the new year. It also cited the heavy floods in Sri Lanka, the Philippines, Brazil and Australia as examples.
The year 2010 also was the wettest on record, according to the Global Historical Climatology Network. But since rain and snowfall patterns varied greatly around the world, scientists say more research is needed to establish a link between the warmer temperatures with the unusual moisture.