2014 was the warmest year on record, with global temperatures 0.68C (1.24F) above the long-term average, US government scientists have said.
The results mean that 14 of the 15 warmest years on record have occurred since the turn of the century.
The analysis was published on Friday by NASA and NOAA researchers.
Last month, the World Meteorological Organization released provisional figures that predicted the past 12 months were set to be record breakers.
The long-term global average temperature is calculated from data collected between 1951 and 1980.
"This is the latest in a series of warm years, in a series of warm decades," said Gavin Schmidt, director of NASA's Goddard Institute for Space Studies.
"While the ranking of individual years can be affected by chaotic weather patterns, the long-term trends are attributable to drivers of climate change that right now are dominated by human emissions of greenhouse gases," he added.
NASA and the US National Oceanic and Atmospheric Administration (NOAA) maintain two of the three global datasets of global temperatures. The UK's Met Office maintains the third.
Data from all three are used by the World Meteorological Organization (WMO) and formed the basis of its provisional figures in December.
Talking to journalists, Dr Schmidt said the results from the two sets of data showed "a lot of warmth in the oceans".
"It shows very clearly that it has been the warmest year on record in the oceans but it wasn't quite the warmest year in the land records but combined it did give us the warmest year," he explained.
PHOTO: A sculpture called "We're fryin' out here" at a beach in Sydney.