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 417.

    Yeah, bloomin scientists. Think they can prove anything with "evidence" and "facts".

  • rate this

    Comment number 416.

    You cannot deny thar global warming is happening right now and threatening our very existence of life on Earth ... the likes of Kiribati and the Marshall Islands are facing possible annihilation as countries because the ocean levels are rising. Fast. Many climate skeptics believe in the existence of an all powerful god that controls life. How ironic when there is ZERO evidence to support that!

  • rate this

    Comment number 415.

    I find it stunning that people are still so ignorant about the changes that they (yes they, it is everyone's responsibility) are causing to our planet. Is it simply denial or genuine stupidity, the data is there, what more does it take? There are catastrophic climate change events in our history, they will happen again, the planet will adapt and survive, it is humanity which will suffer.

  • rate this

    Comment number 414.

    Bring it on, lets muck up the planet, man will die out, hooray, good riddance, we're little more than a parasite anyway. the planet will shrug it's shoulders and just get on with it. Dinosuars had their time, we've had ours. What will be the next dominant species I wonder?

  • rate this

    Comment number 413.

    I heard that if all the icecaps melt, the sea level will rise 90 foot. According to the map on the Environment Quango website, I'd end with sea about 20 feet from my house.

    How cool is that? Probably not so much fun for the people who live a bit lower down the hill, but a couple of kicking-fresh mackerel with a dollop of apple sauce for breakfast every day?

    Gotta be worth it.

  • rate this

    Comment number 412.

    No 136
    Think we need to add the Sun and the rest of the Universe to your model.
    We gain energy from the Sun, that's why it's cooler in the shade, or in a cave.

  • rate this

    Comment number 411.


    As you say outlandish claims are made on both sides of the argument and conclusive 'proof' of how much waming is due to human activity is probably impossible.

    However given that the atmospheric 'greenhouse effect' is about as close as you can get to scientific 'fact', it would seem rather incredible if the volumes of CO2 etc released by human activity had no effect wouldn't it?

  • rate this

    Comment number 410.

    We're only looking at a very small section of time compared to the time life has existed on this planet. Could it just be a coincidence that the temperatures have increased recently?

  • Comment number 409.

    All this user's posts have been removed.Why?

  • rate this

    Comment number 408.

    - Chinese Proverb

    Only after the last tree has been cut down; Only after the last fish has been caught; Only after the last river has been poisoned; Only then will you realize that money cannot be eaten.

  • rate this

    Comment number 407.

    This 'debate' is getting old.

    There are only three things known for certain.

    The World gets warmer and cooler in cycles.

    Our presence on the planet affects these cycles.

    The money men will always do battle with that which affects the way they make money.

  • rate this

    Comment number 406.

    Given that the data is so consistent - the Earth really is warming up - and given that the science behind the greenhouse effect is well-understood I find it hard to understand why there are still so many people who can't accept it.

    Nor can I understand why the UK Government has scuppered the proposed carbon-capture scheme for Longannet in Fife.

  • rate this

    Comment number 405.

    "The Earth's surface really is getting warmer" No kidding! Doesn't the BBC realise that virtually no-one disputes that, the real issue is the cause and magnitude. This is simply a reanalysis of existing data and would be remarkable if it didn't show warming. What is more interesting is that satellite measured temp increases are much less than those shown here. Why the divergence?

  • rate this

    Comment number 404.

    Like many other bloggers, I do not go along with this euphoria that the Earth is becoming warmer, and it is because of man's activities. There has always been climate change - it's called WEATHER. It seems to me that global obsession with this subject is just another excuse to levy so called 'green' taxes.

  • rate this

    Comment number 403.

    Is it so difficult to accept that scientists are for the most part capable, well-trained and conscientious people who are doing a good job? A global community of scientists has been gathering for decades data from all over the world which suggests two things: 1. the world is warming up. 2. The most likely cause is increasing levels of anthropogenic CO2. It is could just be that they are right.

  • rate this

    Comment number 402.

    The real dilemma is that world population is increasing faster than the planet can sustain. We all consume food and therefore we increase the number of farm animals and tear up forests to grow crops. This makes the problem worse.

    But if you reduce the number of people on the planet over time then this will go a long way to alleviating poverty, war and global warming.

    The question is how?

  • rate this

    Comment number 401.

    A bit concerned that this study will be grasped as some vindication for those that support theory that man's actions are somehow to blame for global warming. I doubt anyone doubts these results. What does need to be put to bed with well funded and unbiased research is the myth that the very small contribution of man made CO2 with is itself a minor greenhouse gas has any bearing on climate change.

  • rate this

    Comment number 400.

    @ Episkopian,

    Currently atmospheric C02 concentrations are at their most in 5 million years. These concentrations have risen rapidly from 280ppm in 1860 to 360ppm in 1980. This was a period of previously unprecedented anthroprogenic pollution during a period of rapid industrialisation. These rises in C02 have a strong correlation with rising temperatures and sea-levels since 1860.

  • rate this

    Comment number 399.

    The science is very clear that climate change is real. To those questioning the validity of individual data analysis methods, remember that there are hundreds of data sets from dozens of fields all pointing in exactly the same direction; ice cores and glacier records from geologists, tree ring widths from biologists, fossil data from palaeontologists, the list goes on. All agree disturbingly well.

  • rate this

    Comment number 398.

    Global warming is a problem.

    So is people dying in Africa.

    So is aggression within the family

    So is the endless wars on this planet.

    So is institutionalised alcholism in the West.

    So is sexual repression within society.

    So is a gambling based economy.

    So is scientists making money out of dangerous technology.

    So is people not having emotional intelligence.

    Is anything working actually ?


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