Global warming 'confirmed' by independent study

Weather station at airport Weather stations are giving a true picture of global warming, the group found

Related Stories

The Earth's surface really is getting warmer, a new analysis by a US scientific group set up in the wake of the "Climategate" affair has concluded.

The Berkeley Earth Project has used new methods and some new data, but finds the same warming trend seen by groups such as the UK Met Office and Nasa.

The project received funds from sources that back organisations lobbying against action on climate change.

"Climategate", in 2009, involved claims global warming had been exaggerated.

Emails of University of East Anglia (UEA) climate scientists were hacked, posted online and used by critics to allege manipulation of climate change data.

Fresh start

The Berkeley group says it has also found evidence that changing sea temperatures in the north Atlantic may be a major reason why the Earth's average temperature varies globally from year to year.

Saul Perlmutter The group includes physicist Saul Perlmutter, a Nobel Prize winner this year

The project was established by University of California physics professor Richard Muller, who was concerned by claims that established teams of climate researchers had not been entirely open with their data.

He gathered a team of 10 scientists, mostly physicists, including such luminaries as Saul Perlmutter, winner of this year's Nobel Physics Prize for research showing the Universe's expansion is accelerating.

Funding came from a number of sources, including charitable foundations maintained by the Koch brothers, the billionaire US industrialists, who have also donated large sums to organisations lobbying against acceptance of man-made global warming.

Start Quote

Our biggest surprise was that the new results agreed so closely with the warming values published previously”

End Quote Richard Muller Berkeley group founder

"I was deeply concerned that the group [at UEA] had concealed discordant data," Prof Muller told BBC News.

"Science is best done when the problems with the analysis are candidly shared."

The group's work also examined claims from "sceptical" bloggers that temperature data from weather stations did not show a true global warming trend.

The claim was that many stations have registered warming because they are located in or near cities, and those cities have been growing - the urban heat island effect.

The Berkeley group found about 40,000 weather stations around the world whose output has been recorded and stored in digital form.

It developed a new way of analysing the data to plot the global temperature trend over land since 1800.

What came out was a graph remarkably similar to those produced by the world's three most important and established groups, whose work had been decried as unreliable and shoddy in climate sceptic circles.

graph The Berkeley group's record of global land temperature mirrors existing ones closely

Two of those three records are maintained in the US, by the National Oceanic and Atmospheric Administration (Noaa) and National Aeronautics and Space Administration (Nasa).

The third is a collaboration between the UK Met Office and UEA's Climatic Research Unit (CRU), from which the e-mails that formed the basis of the "Climategate" furore were hacked two years ago.

"Our biggest surprise was that the new results agreed so closely with the warming values published previously by other teams in the US and the UK," said Prof Muller.

"This confirms that these studies were done carefully and that potential biases identified by climate change sceptics did not seriously affect their conclusions."

Since the 1950s, the average temperature over land has increased by 1C, the group found.

They also report that although the urban heat island effect is real - which is well-established - it is not behind the warming registered by the majority of weather stations around the world.

They also showed that in the US, weather stations rated as "high quality" by Noaa showed the same warming trend as those rated as "low quality".

'Time for apology'

Prof Phil Jones, the CRU scientist who came in for the most personal criticism during "Climategate", was cautious about interpreting the Berkeley results because they have not been published in a peer-reviewed journal.

"I look forward to reading the finalised paper once it has been reviewed and published," he said.

Professor Phil Jones The findings so far provide validation for Phil Jones, targeted during the "Climategate" affair

"These initial findings are very encouraging, and echo our own results and our conclusion that the impact of urban heat islands on the overall global temperature is minimal."

The Berkeley team has chosen to release the findings initially on its own website.

They are asking for comments and feedback before preparing the manuscripts for formal scientific publication.

In part, this counters the accusation made during "Climategate" that climate scientists formed a tight clique who peer-reviewed each other's papers and made sure their own global warming narrative was the only one making it into print.

But for Richard Muller, this free circulation also marks a return to how science should be done.

"That is the way I practised science for decades; it was the way everyone practised it until some magazines - particularly Science and Nature - forbade it," he said.

"That was not a good change, and still many fields such as string theory practice the traditional method wholeheartedly."

This open "wiki" method of review is regularly employed in physics, the home field for seven of the 10 Berkeley team.

Bob Ward, policy and communications director for the Grantham Research Institute for Climate Change and the Environment in London, said the warming of the Earth's surface was unequivocal.

"So-called 'sceptics' should now drop their thoroughly discredited claims that the increase in global average temperature could be attributed to the impact of growing cities," he said.

"More broadly, this study also proves once again how false it was for 'sceptics' to allege that the e-mails hacked from UEA proved that the CRU land temperature record had been doctored.

"It is now time for an apology from all those, including US presidential hopeful Rick Perry, who have made false claims that the evidence for global warming has been faked by climate scientists."

Ocean currents

The Berkeley group does depart from the "orthodox" picture of climate science in its depiction of short-term variability in the global temperature.

The El Nino Southern Oscillation (ENSO) is generally thought to be the main reason for inter-annual warming or cooling.

But by the Berkeley team's analysis, the global temperature correlates more closely with the state of the Atlantic Multidecadal Oscillation (AMO) index - a measure of sea surface temperature in the north Atlantic.

There are theories suggesting that the AMO index is in turn driven by fluctuations in the north Atlantic current commonly called the Gulf Stream.

The team suggests it is worth investigating whether the long-term AMO cycles, which are thought to last 65-70 years, may play a part in the temperature rise, fall and rise again seen during the 20th Century.

But they emphasise that anthropogenic global warming (AGW) driven by greenhouse gas emissions is very much in their picture.

"Had we found no global warming, then that would have ruled out AGW," said Prof Muller.

"Had we found half as much, it would have suggested that prior estimates [of AGW] were too large; if we had found more warming, it would have raised the question of whether prior estimates were too low.

"But we didn't; we found that the prior rise was confirmed. That means that we do not directly affect prior estimates."

The team next plans to look at ocean temperatures, in order to construct a truly global dataset.

Follow Richard on Twitter


More on This Story

Related Stories

The BBC is not responsible for the content of external Internet sites


This entry is now closed for comments

Jump to comments pagination
  • rate this

    Comment number 257.

    To quote the late Carl Sagan, freethinker and sceptic;

    "Extraordinary claims require extraordinary evidence"

    Balance of probability, allied to peer review, allied to weight of evidence.

  • rate this

    Comment number 256.


    Should the name for this phenomenon revert back to "Global Warming", or should we continue to use "Climate Change"?

  • rate this

    Comment number 255.

    like others on here, I don`t disagree that the planet may be warming, I am sceptical that it is humanity is to blame. For millions of years the planet has warmed up and frozen again. Climates across the world have changed, what was once tropical has become a desert and vice a versa. Global warming has become a scam for making money through green taxes

  • rate this

    Comment number 254.

    Climategate was not about the CRU land temperature or even the ocean temperatures where there is more uncertainty and it will be good to see the Berkeley Earth Project move onto this.

    Climategate was about the 'Hockey Stick', a discredited paleoclimate reconstuction.

  • rate this

    Comment number 253.

    Re 242. Socrates Smith
    The ancients believed that sun orbited the earth. A few thousand years later we know they were wrong. In a few thousand years our descendants will laugh at our "CO2 driven temperature rise" fan dance."

    You got it the wrong way round. The old dogma hundreds of years back was to think climate change was all natural. now we know better.

  • rate this

    Comment number 252.

    The report says the studies show a temperature rise of 1 deg since 1950. In the interest of accuracy, so important in this context, the rise shown is around 0.8 to 0.9 deg, This may seem a tiny difference, but the report has rounded up the increase by around 11 to 25%.

  • rate this

    Comment number 251.

    When the met office cannot predict what the weather is like in a week's time, how can they tell us what will happen in 50 years"

    Weather and climate are not the same thing. It is a relatively simple task to work out the change in energy content in a system over long periods of time. It is a very different task to predict the instantaneous energy distribution at points in that system.

  • rate this

    Comment number 250.

    I have low energy light bulbs. Every watt of heat that was "wasted" by the old bulbs is now replaced by heat from my central heating, since the temperature of the rooms is thermostatically controlled. Please tell me how this saves the planet. Low energy bulbs use far more energy to make and contain mercury and phosphor which will both end up in the environment. They last no longer either!

  • rate this

    Comment number 249.

    192.Total Mass Retain
    14 Minutes ago
    "Sidney Monroe
    CO2 in the atmosphere = 0.032 per cent."

    There you go again Mr Retain. Do you deny that scientists have made ridiculous predictions about the affects of global warming?

  • rate this

    Comment number 248.

    "SeeDubya. It is in their own financial interest to show that warming is taking place (because it is a seemingly limitless pot of grant money"

    Do you doubt the science coming from CERN because it was funded by "grant money" or the "Big Bang theory" for the same reason. Those with the analytical and computational skills of climate scientists could easily get lucrative employ elsewhere.

  • rate this

    Comment number 247.

    As it has been proven that the earth has experienced extreme temperature cycles in the past, why could this not be just one of those? Just because we have come to love the climate of the last 150 years does not mean we are able to maintain it if nature chooses to change. Trying to keep the temperature rise to 2C is a little like King Canute trying to stop the tide coming in.

  • rate this

    Comment number 246.

    Get rid of road humps, bus lanes and carry out roadworks more efficiently. That should save a bit on emmissions

  • rate this

    Comment number 245.

    The financial crisis is directly linked to our pollution, I have no doubt that when we become kinder to the atmosphere (breathing in exhaust fumes) our financial situation will improve and we should focus solely on the environment and not spend vast amounts of wasted time concentrating on money

  • rate this

    Comment number 244.

    Just now
    When the polar bear is extinct and Norfolk is underwater...


    You're dreaming.

    When all the the above happens and the deniers are swimming to work at the seaweed plantation, they'll still be saying 'well there's nothing I could have done differently'.

  • rate this

    Comment number 243.

    Hmm.. "so what" comes to mind.

    We KNOW the temperatures are rising, the question still remains if the human impact is as significant as some claim, or is it a natural cycle? Still no answers on that what REALLY matters it seems.

  • rate this

    Comment number 242.

    The ancients believed that sun orbited the earth. A few thousand years later we know they were wrong. In a few thousand years our descendants will laugh at our "CO2 driven temperature rise" fan dance. In Britain in the meantime we freeze through the winter whilst sitting on top of a 200 year plus supply of coal. We should dig it up, burn it (efficient combined cycle) and save ourselves.

  • rate this

    Comment number 241.

    It's been dropping to near freezing in parts of the UK. I don't think much of this 'warming' while I'm putting the heating on, scared to death of the gas bill that goes up by 40% every few months. I don't think the utility companies are overly concerned by it either, somehow.

  • rate this

    Comment number 240.

    a few moments ago i added a comment, but do to "space or ?" i limited out. difficult to make a science response to be understood by general public. usually, we old lecturers frame our material presented to our listeners based on their level of education. the only lecturer who could often bridge this gap was richard feymann who was truly amazing.

  • rate this

    Comment number 239.

    Global warming is a nice scam where governments can tax people more and claim some sort of moral basis

  • rate this

    Comment number 238.

    When will people realise that regardless of the cause, global warming IS occuring? Our way of life as we know it, whether in the West or developing countries is facing a grave threat.

    Is it not time that we put aside the arguments and concentrate on limiting the damage? We burn billions of tonnes each year - how can that NOT have an effect?


Page 42 of 54


More Science & Environment stories



BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.