Global warming ‘confirmed’ by independent study
By Richard Black, from BBC News
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.
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.
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.
“Our biggest surprise was that the new results agreed so closely with the warming values published previously.”
“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 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.
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”.
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.”
Dr. Pinna says:
We really don’t need this “Proof.”
It took millions of years of sunlight as energy to make the oil and coal and gas that we take from the ground. That energy from the sun did not disappear.
It is contained in the hydrocarbons (oil, coal, gas) that we extract from the earth and then burn. When we burn the hydrocarbons (oil, coal, gas) we release millions of years of heat from the sun.
As a consequence, Planet Earth becomes hotter. As we continue to burn hydrocarbons it will shortly become intolerably hot.