The numbers are in. The year 2014 – after shattering temperature records that had stood for hundreds of years across virtually all of Europe, and roasting parts of South America, China and the Russian far east – was the hottest on record, with global temperatures 0.69 degrees (1.24F) higher than the 20th century average, US government scientists said on Friday.
A day after international researchers warned human activities had pushed the planet to the brink, new evidence of climate change arrived.
The world was the hottest it has been since systematic records began in 1880, especially on the oceans, which the agency confirmed were the driver of 2014’s temperature rise.
The global average temperatures over land and sea surface for the year was 0.69 degrees (1.24F) above the 20th century average, the National Oceanic and Atmospheric Administration (Noaa) and Nasa reported.
The scientists said 2014 was 0.04 degrees (0.07F) higher than the previous records set in 2005 and 2010, and the 38th consecutive year of above average temperatures.
That means nobody born since 1976 has experienced a colder than average year.
Any one year being a record warm one is not in itself particularly significant, but this is one in a series of record warm years that are driven by the continuing underlying long-term global warming," said Gavin Schmidt, director of Nasa's Goddard Institute of Space Studies.
“We expect that heat records will continue to get broken – not everywhere and not every year – but increasingly and that does not bode well for a civilisation that is continuing to add greenhouse gases to the atmosphere at an increasing rate.”
The findings from Nasa and Noaa were in line with reports from the United Nations weather organisation, the UK Met Office and Japan's meteorological agency confirming the steadily upward march of temperatures over the last decades.
Thirteen of the 15 hottest years have occurred since 2000. “1988 was also a record warm year at the time. Now it doesn’t even rank in the top 20,” Schmidt said.
Campaign groups said the milestone ought to spur new efforts to fight climate change. “The Obama administration must back international efforts to achieve zero carbon emissions by 2050,” said Shaye Wolf, climate science director with the Center for Biological Diversity.
“We need a global agreement that keeps most dirty fossil fuels in the ground and provides ample support for developing nations to leapfrog into clean-energy economies.”
Ocean surface temperatures were far warmer in 2014 than any year on record, especially in the northern Pacific.
In April, westerly winds began spreading that very warm water out along the equator to the eastern Pacific and around to the Gulf of Alaska – releasing heat that had been locked in the depths for nearly a decade.
The unusually warm waters shifted hurricane tracks, weakened trade winds, and led to widespread bleaching of coral reefs in Hawaii.
Vast expanses of the northwestern and southeastern Atlantic, most of the Norwegian Sea, and parts of the central to southern Indian Ocean were also extraordinarily warm.
Global sea-surface temperatures were 0.57 degrees (1.03F) above the 20th century average.
On land, temperature records toppled almost everywhere.
A great swathe of Europe and parts of North Africa sweated out heat waves. Britain saw its hottest summer in three and a half centuries.
Ireland had one of its warmest years in history last year with average temperatures just 0.2 degrees below the record set in 2007.
An average temperature of 10.6 degrees was recorded across the country in 2014. It made 2014 the joint fourth warmest year on record along with 1997 and 1949. The three warmest years were 2007, 2006 and 1945.
Transport crew in Norway had to hose down runways to prevent them buckling in the heat. Finns were warned they may soon face Decembers without snow. Australia had a series of heat waves.
For North America – aside from California and Alaska – it was the opposite story. The year was so cold it spawned two new meteorological terms: polar vortex for the Arctic blast at the beginning of the year and lake effect, for the 2ft of snow dumped on Buffalo in November.
But California saw its hottest year, with annual average temperatures 2.3C (4.1F) higher than 20th century average, and scant relief for a punishing drought.
Elsewhere, Argentina was plagued by water shortages and power blackouts as extreme heat engulfed South America, setting new temperature records in Brazil and Bolivia.
The year also brought heavy rainfall and flooding in some countries.
Parts of Turkey saw five times the normal amount of rain, and France experienced its wettest summer since 1959.
Rivers broke up earlier than ever recorded in Siberia. Millions of people were affected by heavy rains and severe flooding in northern Bangladesh, northern Pakistan and India.
Sea ice extent was below average on the Pacific side of the Arctic and near-average on the Atlantic side.