Has global warming stopped? No - it’s just on pause, insist scientists, and it's down to the oceans

Temperatures still expected to reach predicted 2015 levels with only a five-year delay after 12 of the 14 hottest years on record

Science Editor

Huge amounts of heat – equivalent to the power of 150 billion electric kettles – are being continuously absorbed by the deep ocean, which could explain why global warming has “paused” over the past 10 to 15 years, scientists have concluded in a series of reports to explain why the Earth’s rate of warming has slowed down.

Global average temperatures are higher now than they have ever been since modern records began. However, after a period of rapid temperature increases during the 1980s and 1990s there has been a significant slow-down since the turn of the century, leading some sceptics to claim that global warming has stopped.

A scientific assessment of the planet’s heat balance has found that the most likely explanation for the recent hiatus in global warming is the continual absorption of thermal energy by the huge “heat sink” of the deep ocean many hundreds of metres below the sea surface, according to scientists from the Met Office.

Senior climate scientists said that they had always expected periods when the rate of increase in temperatures would level off for a few years and emphasised that the last decade was still warmer than any previous decade, with 12 of the 14 hottest years on record occurring since 2000.

Professor Rowan Sutton, a climate scientist at Reading University, said the temperatures have levelled off in the past, the latest example being in the 1940s and 1950s when sulphate pollutants from the post-war boom in industrial production may have acted as a shield against incoming solar radiation.

“Some people call it a slow-down, some call it a hiatus, some people call it a pause. The global average surface temperature has not increased substantially over the last 10 to 15 years,” Professor Sutton said.

“Climate scientists absolutely expect variations in the rate at which surface temperature will rise….but that is not to say we understand all the details of the last 10 to 15 years,” Professor Sutton said.

The problem for the Met Office is to explain why the rate of increase in global temperatures has declined in recent years while concentrations of carbon dioxide in the atmosphere have continued to accelerate. Sceptics claim that this shows there is not a strong link between the two, whereas climate scientists insist that rising carbon dioxide concentrations are largely responsible for the rise in global temperatures.

Professor Stephen Belcher, head of the Met Office Hadley Centre, said that a pause in the rate of increase in global temperatures lasting this long is unusual but not exceptional, with similar pauses of about 10 years expected on average twice every century.

The most likely explanation for the current pause is that excess heat trapped by carbon dioxide in the atmosphere is being transferred from the atmosphere to the oceans where it is being transported down to deeper layers that cannot be monitored by satellites, Professor Belcher said.

“It looks like the Earth is continuing to accumulate energy but it looks like it is being re-arranged and hidden from view,” he said.

However, measurements from hundreds of ocean floats released over the last decade, which descend and drift to depths of up to 2,000 metres, show that huge amounts of heat from the sea surface is now being transferred to the deep ocean, with unknown consequences for the environment, the scientists said.

“In summary, observations of ocean heat content and of sea-level rise suggest that the Earth system has continued to absorb heat energy over the past 15 years, and that this additional heat has been absorbed in the ocean,” says the Met Office report.

The pause, however, is unlikely to change the predictions over the future course of global warming. Temperature increases expected by 2015 will only be delayed by a further five or ten years, the scientists said. Average surface temperatures are still on course to increase by 2C this century, with further rises expected by the end of the century if nothing is done to curb carbon dioxide emissions, they said.

It is not possible to account for the recent lack of surface warming solely by looking at the difference between amount of heat being received from the Sun and the amount of thermal energy being lost from the planet – calculations show that extra heat continues to be absorbed by the Earth at a rate of 0.6 Watts per square metre, equivalent to about 300bn 1KW electric heaters or 150bn 2KW kettles distributed across the planet.

“Observations of ocean heat content and of sea-level rise suggest that the additional heat from the continued rise in atmospheric carbon dioxide concentrations has been absorbed in the ocean and has not been manifest as a rise in surface temperature,” the Met Office says in one of its three reports into the global warming pause.

“Radiated forcing by greenhouse gases has continued unabated; that heat is being held in the system but is not manifest as a rise in global mean surface temperature. Observations of ocean heat content and of sea-level rise suggest that this additional heat has been absorbed by the ocean,” it says.

News
people
Arts and Entertainment
Armstrong, left, and Bain's writing credits include Peep Show, Fresh Meat, and The Old Guys
TVThe pair have presented their view of 21st-century foibles in shows such as Peep Show and Fresh Meat
Arts and Entertainment
Keys to success: Andrew and Julian Lloyd Webber
arts + entsMrs Bach had too many kids to write the great man's music, says Julian Lloyd Webber
Sport
footballMan City manager would have loved to have signed Argentine
PROMOTED VIDEO
Have you tried new the Independent Digital Edition apps?
News
ebooksAn unforgettable anthology of contemporary reportage
News
people
News
i100
Arts and Entertainment
Hand out press photograph/film still from the movie Mad Max Fury Road (Downloaded from the Warner Bro's media site/Jasin Boland/© 2014 Warner Bros. Entertainment Inc.)
films'You have to try everything and it’s all a process of elimination, but ultimately you find your path'
Arts and Entertainment
Imelda Staunton as Dolores Umbridge in the Harry Potter films
books

New essay by JK Rowling went live on Pottermore site on Friday

News
people

Top Gear presenter is no stranger to foot-in-mouth controversy

News
Russia Today’s new UK channel began broadcasting yesterday. Discussions so far have included why Britons see Russia as ‘the bad guy’
news

New UK station Russia Today gives a very bizarre view of Britain

Arts and Entertainment
Keira Knightley and Benedict Cumberbatch at the premiere of The Imitation Game at the BFI London Film Festival
filmsKeira Knightley tried to miss The Imitation Game premiere to watch Bake Off
News
i100
Sport
Enner Valencia
footballStriker has enjoyed a rapid rise to fame via winning the title with ‘The Blue Ballet’ in Ecuador
Arts and Entertainment
A top literary agent has compared online giant Amazon to Isis
arts + entsAndrew Wylie has pulled no punches in criticism of Amazon
Arts and Entertainment
Charlie Sheen said he would
tv

Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Mobile Developer (.NET / C# / Jason / Jquery / SOA)

£40000 - £65000 per annum + bonus + benefits + OT: Ampersand Consulting LLP: M...

Humanities Teacher - Greater Manchester

£22800 - £33600 per annum: Randstad Education Manchester Secondary: The JobAt ...

Design Technology Teacher

£22800 - £33600 per annum: Randstad Education Manchester Secondary: Calling al...

Foundation Teacher

£100 - £125 per day: Randstad Education Chelmsford: EYFS Teachers - East Essex...

Day In a Page

Bryan Adams' heartstopping images of wounded British soldiers to go on show at Somerset House

Bryan Adams' images of wounded soldiers

Taken over the course of four years, Adams' portraits are an astonishing document of the aftermath of war
The drugs revolution starts now as MPs agree its high time for change

The drugs revolution starts now as MPs agree its high time for change

Commons debate highlights growing cross-party consensus on softening UK drugs legislation, unchanged for 43 years
The camera is turned on tabloid editors in Richard Peppiatt's 'One Rogue Reporter'

Gotcha! The camera is turned on tabloid editors

Hugh Grant says Richard Peppiatt's 'One Rogue Reporter' documentary will highlight issues raised by Leveson
Fall of the Berlin Wall: It was thanks to Mikhail Gorbachev that this symbol of division fell

Fall of the Berlin Wall

It was thanks to Gorbachev that this symbol of division fell
Halloween 2014: What makes Ouija boards, demon dolls, and evil clowns so frightening?

What makes ouija boards and demon dolls scary?

Ouija boards, demon dolls, evil children and clowns are all classic tropes of horror, and this year’s Halloween releases feature them all. What makes them so frightening, decade after decade?
A safari in modern Britain: Rose Rouse reveals how her four-year tour of Harlesden taught her as much about the UK as it did about NW10

Rose Rouse's safari in modern Britain

Rouse decided to walk and talk with as many different people as possible in her neighbourhood of Harlesden and her experiences have been published in a new book
Welcome to my world of no smell and odd tastes: How a bike accident left one woman living with unwanted food mash-ups

'My world of no smell and odd tastes'

A head injury from a bicycle accident had the surprising effect of robbing Nell Frizzell of two of her senses

Matt Parker is proud of his square roots

The "stand-up mathematician" is using comedy nights to preach maths to big audiences
Paul Scholes column: Beating Manchester City is vital part of life at Manchester United. This is first major test for Luke Shaw, Angel Di Maria and Radamel Falcao – it’s not a game to lose

Paul Scholes column

Beating City is vital part of life at United. This is first major test for Shaw, Di Maria and Falcao – it’s not a game to lose
Frank Warren: Call me an old git, but I just can't see that there's a place for women’s boxing

Frank Warren column

Call me an old git, but I just can't see that there's a place for women’s boxing
Adrian Heath interview: Former Everton striker prepares his Orlando City side for the MLS - and having Kaka in the dressing room

Adrian Heath's American dream...

Former Everton striker prepares his Orlando City side for the MLS - and having Kaka in the dressing room
Simon Hart: Manchester City will rise again but they need to change their attitude

Manchester City will rise again but they need to change their attitude

Manuel Pellegrini’s side are too good to fail and derby allows them to start again, says Simon Hart
Isis in Syria: A general reveals the lack of communication with the US - and his country's awkward relationship with their allies-by-default

A Syrian general speaks

A senior officer of Bashar al-Assad’s regime talks to Robert Fisk about his army’s brutal struggle with Isis, in a dirty war whose challenges include widespread atrocities