“It is very likely that 2013 will be one of the warmest 10 years in the record which goes back to 1850, and it is likely to be warmer than 2012,” the Met Office said on Thursday (20 December).
Next year was expected to be between 0.43 and 0.71 degrees Celsius warmer than the long-term global average of 14 degrees (1961-1990), with a best estimate of around 0.57, it said.
The forecast is based on Met Office research, as well as data from the University of East Anglia, the NASA Goddard Institute of Space Studies and the US National Oceanic and Atmospheric Administration.
Rising temperatures could be due to the natural variability of the climate and global warming from increasing greenhouse gas emissions, said Dave Britton, a Met Office forecaster.
A warmer global average temperature does not necessarily mean every region of the world will get hotter, as regional climate variability produces different effects in different parts of the world, he added.
Eleven of the 12 hottest years on record have occurred since 2001, according to data from the World Meteorological Organisation.
Last year is ranked the warmest on record, having been 0.54 degrees above the long-term average, while 2012 is ranked the ninth warmest, with a rise of 0.45 degree Celsius.
Rising global temperatures
Most scientists blame increasing temperatures on man-made greenhouse gas emissions from burning fossil fuels, and say they can lead to rising sea levels and extreme weather events such as superstorm Sandy that hit the US east coast in October.
Last week, a leaked draft report from the Intergovernmental Panel on Climate Change showed that global average temperatures could be more than 2 degrees above average by 2100, and could reach 4.8 degrees.
Low-lying island states and other countries vulnerable to rising sea levels, floods and hurricanes have been putting pressure on developed countries to curb greenhouse gas emissions and keep the rise in temperatures to within a limit of 2 degrees this century.
Global carbon dioxide emissions hit a record high in 2011, led by China, the International Energy Agency said in May.
A UN conference aimed at curbing emissions ended this month with little progress.