BOSTON • With an El Nino growing in the Pacific Ocean and climate change spurring global temperatures ever higher, almost nothing can stop the earth from breaking 2014's mark for the warmest year on record.
The average annual temperature last year was about 0.7 deg C above the 20th-century average, making it the warmest year in records going back to 1880, according to the US National Centres for Environmental Information (NCEI). Through July, 2015 is on pace to surpass that.
"It is global warming, and the El Nino that is enhancing global temperatures," said Ms Jessica Blunden, a climatologist with ERT Inc working at the agency in Asheville, North Carolina.
"The likelihood that 2015 will fall lower than 2014 gets smaller and smaller every month you go forward," she added.
The record set in 2014 marked the third time in the 21st century that a new high annual temperature was set or tied and the 38th consecutive year that annual temperatures exceeded the long-term average. Nine of 10 of the warmest years have occurred since 2002. If 2015 sets a new mark, it will be the first time back-to-back records have been set since 1997-98, she said.
The record set in 2014 marked the third time in the 21st century that a new high annual temperature was set or tied and the 38th consecutive year that annual temperatures exceeded the long-term average.
Those two years were also when the strongest El Nino, a warming of the equatorial Pacific Ocean, occurred in records dating to 1950.
There is a 85 per cent chance the El Nino will last into the February-April period, the US Climate Prediction Centre has said. There is also a strong possibility it will be one of the most intense in the last 65 years.
Ms Blunden said the fact that 2015 is trending even warmer than during the last strong El Nino shows that all the heat in the world is not caused by the ocean. When you take away the El Ninos, temperatures will still likely be higher in 2015, she said.
In addition to the period from January through July being the warmest on record, July was the warmest month ever recorded on earth since 1880, the NCEI said last Thursday.
"It's reaffirming what we already know: the world is warming," said Dr Jake Crouch, a physical scientist at the centre, in a conference call with reporters. "It's time for us to start looking at what are the impacts of that."
The NCEI's monthly analysis showed Austria had its warmest July in records going back to 1767, Dr Crouch said. Heat waves also gripped parts of Britain, the Netherlands, Sweden and France, which experienced its third-hottest July.