Global warming 'confirmed' by independent study

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

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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.

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  • rate this

    Comment number 217.

    The problem with all this "science" is that it is not objective. It is in their own financial interest to show that warming is taking place (because it is a seemingly limitless pot of grant money). I took a data set I found from an Anglesey station that has measured sea temperatures for 150 years and when I plotted it the trendline was a flat as a pancake. These guys would just discard that data!

  • rate this

    Comment number 216.

    Could this warming be caused by the sun, that big yellow ball 1,000,000 times the size of our earth and the provider of all our heat. nah doubt it.

  • rate this

    Comment number 215.

    At last - real science is being done!

  • rate this

    Comment number 214.

    #160 SteveM
    Heard of Phlogiston ?

    Scientists in the 20s and 30s 'proved' that non-Nordic people were inferior
    It's about eugenics in California which passed laws enforcing segregation and forced sterilisation for scientific reasons

    The promoters of these laws studied science

    Science was the religion of the 20th century. Don't make the same mistake in the 21st

  • rate this

    Comment number 213.

    I am still not totally convinced about mans input into this problem, one huge volcanic eruption would produce more troublesome gasses than the entire global man made output since man evolved"

    No it doesn't. Please stop repeating such discredited arguments. Man's CO2 emissions are about 200x greater than those due to volcanoes each year.

  • rate this

    Comment number 212.

    It has been shown to be true that variations in the earth's temperature come in cycles. It can spend a maybe a thousand, maybe a million or so years) in an ice age, then it warms up, and spends another millennium in a period of hotter than average temperatures.

    These cycles have been happening for millions of years, so why are we concerned that something the human race is doing will change it?

  • rate this

    Comment number 211.

    Daniel (113): Yes, science ned sceptics - but there's a difference between sceptisicm and simple denial. Study after study has shown the overwhelming probablility that man-made climate change is real. Do you really still want to bet the planet on the slim remaining chance the denialists are right?

  • rate this

    Comment number 210.

    Actually I am far more interested in why the banks and their political reps. are above any law.
    Fat chance that'll be discussed.
    Until then what chance sane policies?

  • rate this

    Comment number 209.

    70% of the Earths surface is water which driives the weather. 30% is land of which humans occupy 10% (3% of the Earths total surface). We are not that important in driving the climate. The Earth will do as it pleases.

  • rate this

    Comment number 208.

    M2C2 is, in itself, simply a distraction. It's removing the argument from the problem, and the solution. On our planet we've natural CO2 capture - plants. We have CO2 producers - animals. Earth can cope with an imbalance for a period of time, but not indefinitely. As animal life increases and plant life decreases we move toward catastrophe. The solution? More plants, less animals (read 'humans').

  • rate this

    Comment number 207.

    It is now time for the BBC to take climate change science seriously. For far too long BBC programmes tackling issues like wind farms and aviation expansion have refused to allow the underlying issue of climate change to feature in the debate. The BBC has wrongly painted such issues in nimbyist terms.

  • rate this

    Comment number 206.

    They wont give up, will they? IA 1 degree rise in sixty years. No attempt to offer other explanations. It's global warming or nothing, it seems. Looking at the groups involved here, including NASA and that university again, I wouldnt trust the data any further than I could throw it and neither should anyone else unless you're desperate to pay swingeing carbon taxes.

  • rate this

    Comment number 205.

    Sceptics, is your main concern that you may have to give up driving a high performance petrol driven car.

    Your argument seems to be based on the scientific "stuff & nonsense" approach or the in depth science which sells shampoo.

    Every time one of your arguments is proved false, up pops another one. They seem to originate in research carried out by scientists who work for the oil industry.

  • rate this

    Comment number 204.

    @194.Vladimir Tepes

    Exactly. So all green taxes and people who think climate change is humanities greatest threat need to go crawl under the rock they came from. It's just insulting that the governments have listened to this tosh made up by a few idiots who didn't do any research into the matter. If science worked like that, we'd still believe the Earth was made in 7 days.

  • rate this

    Comment number 203.

    'Global warming 'confirmed' by independent study'

    (Fingers in ears)

    La la la la la globle conspiracy.

    La la la la la natural warming cycle.

    La la la la la excuse to raise taxes.

    La la la la la quote non-peer reviewed 'science'

    La la la lal la etc.......

  • rate this

    Comment number 202.

    A couple of definitions for you.

    Sceptic: One who seeks proof of something before believing it.

    Denier: One who will refuse to believe something, no matter what proof is offered.

    Those who performed this study were sceptics, those still refusing to admit that global warming is real and is largely due to human activities are deniers.

  • rate this

    Comment number 201.

    "168.steve barnett
    Hmm ther's an unholy alliance."

    An unholy alliance that would struggle to last a nanosecond let alone 30 years. If you truly believe that tax hungry governments across the world, grant hungry scientists (who can find lucrative employ elsewhere), the eco lobby, oil companies and many others are in a mass conspiracy then ratiional argument will not persuade you.

  • rate this

    Comment number 200.


    They don't seem to mention the fact that almost all monitoring stations that showed static or FALLING temperature have been removed ("bad placement causing misleading readings" - but areas where temperature increase has been found - have had EXTRA monitoring stations added.

    If people truly reckon that is good science, they deserve to me mislead I guess.

  • rate this

    Comment number 199.

    The study/article only says that they found that the climate is warming. It's interesting to see the huge amount of commenters who automatically extrapolate from that and are saying it confirms that the warming is man-made...

  • rate this

    Comment number 198.

    A fourth question...

    Has this study been through peer-review yet?


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