The figures are in, and it's not a mistake, an exaggeration or a hoax, scientists say -- 2014 was the warmest year on record, confirming a warming trend and increasing climate worries.
The past year's average temperature was the highest ever recorded since detailed records began to be kept 135 years ago, scientist at NASA and the National Oceanic and Atmospheric Administration say.
They weren't alone in their determination; Japan's national weather agency as well as independent researchers at the University of California, Berkeley, also confirmed 2014 as the warmest year on record.
The year's average temperature, 58.24 degrees Fahrenheit (14.58 C) was 1.24 degrees F (0.69 C) above the 20th century average, NOAA scientists said.
NASA calculates temperatures a bit differently but its figures were within tenths of a degree of the NOAA numbers, with their year's average 1.22 degrees F over the average recorded between 1951 and 1980.
The last month of 2014 "sealed the deal" as it set a record for the warmest December ever recorded, NOAA scientists said.
The findings should end claims by some that warming has stopped, climate experts said, and the global warming development can be laid at the feet of human activities, including the burning of fossil fuels and the resulting emission of greenhouse gases.
"Greenhouse gas trends are responsible for the majority of the trend that we see," said Gavin Schmidt, head of NASA's Goddard Institute for Space Studies in New York, and since such emissions are likely to continue to rise, "we may anticipate further record highs in the years to come."
Land temperatures were only the fourth highest ever recorded, but every ocean saw new temperature highs, driving the global average up, he said.
"This was very clearly the warmest year in the ocean records," Schmidt said. "It wasn't quite the warmest year in the land records, but combined, this did actually give the warmest year."
All parts of the world saw elevated temperatures in 2014, the researchers said, including the far east of Russia, much of Europe, the western U.S., northern Africa, the interior of South America and regions of Australia.
"Every continent had some aspect of record high temperatures," said Tom Karl of NOAA's National Climatic Data Center.
Nine of the 10 hottest years on record have occurred since the year 2000, NOAA global records show.
"This is the latest in a series of warm years, in a series of warm decades," said NASA's Schmidt.
