NASA ranks 2017 as the second-hottest year ever

The last three years were the hottest on record, according to a new UN report, and 2017 was the second-warmest ever

The last three years were the hottest on record, according to a new UN report, and 2017 was the second-warmest ever.

Last year was the second hottest year on record, after 2016 and on a par with 2015, data shows.

Fresh data has revealed that "2015, 2016, and 2017 have been confirmed as the warmest years" since records began in the 19th Century, the World Meteorological Organisation (WMO) said.

The WMO said that 2016 remained the hottest year ever measured due to the warming effect of El Nino.

This map shows Earth’s average global temperature from 2013 to 2017, as compared to a baseline average from 1951 to 1980, according to an analysis by NASA’s Goddard Institute for Space Studies. Yellows, oranges, and reds show regions warmer than the baseline. (Photo: NASA)
This map shows Earth’s average global temperature from 2013 to 2017, as compared to a baseline average from 1951 to 1980, according to an analysis by NASA’s Goddard Institute for Space Studies. Yellows, oranges, and reds show regions warmer than the baseline. (Photo: NASA)

The warmest ever non-El Nino year was 2017, which was hotter than 2015 by less than one hundredth of a degree.

Nasa rates 2017 the second hottest year, and Noaa and the Met Office judge it to be the third hottest since records began in 1850.

The years 2016 and 5015 were affected by El Niño - the natural phenomenon centred on the tropical Pacific Ocean which works to boost temperatures worldwide.

An analysis of five international datasets revealed that the global average surface temperature in 2017 was roughly 1.1C above the pre-industrial era.

"The long-term temperature trend is far more important than the ranking of individual years, and that trend is an upward one," said WMO secretary-general Petteri Taalas.

"Seventeen of the 18 warmest years on record have all been during this century, and the degree of warming during the past three years has been exceptional.

"Arctic warmth has been especially pronounced and this will have profound and long-lasting repercussions on sea levels, and on weather patterns in other parts of the world."

The globally averaged temperature in 2017 was about 0.46C above the 1981-2010 long-term average of 14.3C, according to the UN's meteorologists.

Researches say that if one had to take out this natural variability, 2017 would probably have been the warmest year yet.

"It's extraordinary that temperatures in 2017 have been so high when there's no El Niño. In fact, we’ve been going into cooler La Niña conditions,” the acting director of the UK Met Office, Prof Peter Stott, told BBC News.

"Last year was substantially warmer than 1998 which had a very big El Niño. It shows clearly that the biggest natural influence on the climate is being dwarfed by human activities – predominantly CO₂ emissions."

In addition to rising greenhouse gas levels in the atmosphere which is causing global warming, the climate also has naturally occuring phenomena which affect the surface temperature.

Cyclical conditions including El Nino, which has a warming influence, and La Nina, which has a cooling influence, are reflected in data.

"The strong 2015-16 El Nino contributed to the record temperature in 2016. By contrast, 2017 started with a very weak La Nina and also finished with a weak La Nina," said the WMO.

Earlier this week, a study in the journal Nature concluded that climate change needed urgently to be tackled, but forecast that apocalyptic predictions of a temperature rise of 6C by 2100 would not come about.

Professor Richard Allan from the University of Reading said: “Rather than warming being inconsequential or catastrophic, as some have suggested, we can be sure societies are facing a dangerous temperature rise, but one which we still have time to fix.

“The conclusions confirm that human-caused climate change is a serious concern. But if we act now with sustained and substantial cuts in greenhouse gas emissions, societies will still be able to avoid much of the most dangerous climate change predicted by computer simulations.”

 

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