The confession  (warning, not peer reviewed ;-)  -G

The Case Against Global-Warming Skepticism; There were good reasons for
doubt, until now.
Richard A. Muller.  Wall Street Journal (Online).  New York, N.Y.:Oct 21,
2011. 

Are you a global warming skeptic? There are plenty of good reasons why you
might be.

As many as 757 stations in the United States recorded net
surface-temperature cooling over the past century. Many are concentrated in
the southeast, where some people attribute tornadoes and hurricanes to
warming.

The temperature-station quality is largely awful. The most important
stations in the U.S. are included in the Department of Energy's Historical
Climatology Network. A careful survey of these stations by a team led by
meteorologist Anthony Watts showed that 70% of these stations have such poor
siting that, by the U.S. government's own measure, they result in
temperature uncertainties of between two and five degrees Celsius or more.
We do not know how much worse are the stations in the developing world.

Using data from all these poor stations, the U.N.'s Intergovernmental Panel
on Climate Change estimates an average global 0.64ºC temperature rise in the
past 50 years, "most" of which the IPCC says is due to humans. Yet the
margin of error for the stations is at least three times larger than the
estimated warming.

We know that cities show anomalous warming, caused by energy use and
building materials; asphalt, for instance, absorbs more sunlight than do
trees. Tokyo's temperature rose about 2ºC in the last 50 years. Could that
rise, and increases in other urban areas, have been unreasonably included in
the global estimates? That warming may be real, but it has nothing to do
with the greenhouse effect and can't be addressed by carbon dioxide
reduction.

Moreover, the three major temperature analysis groups (the U.S.'s NASA and
National Oceanic and Atmospheric Administration, and the U.K.'s Met Office
and Climatic Research Unit) analyze only a small fraction of the available
data, primarily from stations that have long records. There's a logic to
that practice, but it could lead to selection bias. For instance, older
stations were often built outside of cities but today are surrounded by
buildings. These groups today use data from about 2,000 stations, down from
roughly 6,000 in 1970, raising even more questions about their selections.

On top of that, stations have moved, instruments have changed and local
environments have evolved. Analysis groups try to compensate for all this by
homogenizing the data, though there are plenty of arguments to be had over
how best to homogenize long-running data taken from around the world in
varying conditions. These adjustments often result in corrections of several
tenths of one degree Celsius, significant fractions of the warming
attributed to humans.

And that's just the surface-temperature record. What about the rest? The
number of named hurricanes has been on the rise for years, but that's in
part a result of better detection technologies (satellites and buoys) that
find storms in remote regions. The number of hurricanes hitting the U.S.,
even more intense Category 4 and 5 storms, has been gradually decreasing
since 1850. The number of detected tornadoes has been increasing, possibly
because radar technology has improved, but the number that touch down and
cause damage has been decreasing. Meanwhile, the short-term variability in
U.S. surface temperatures has been decreasing since 1800, suggesting a more
stable climate.

Without good answers to all these complaints, global-warming skepticism
seems sensible. But now let me explain why you should not be a skeptic, at
least not any longer.

Over the last two years, the Berkeley Earth Surface Temperature Project has
looked deeply at all the issues raised above. I chaired our group, which
just submitted four detailed papers on our results to peer-reviewed
journals. We have now posted these papers online at to solicit even more
scrutiny.

Our work covers only land temperature--not the oceans--but that's where
warming appears to be the greatest. Robert Rohde, our chief scientist,
obtained more than 1.6 billion measurements from more than 39,000
temperature stations around the world. Many of the records were short in
duration, and to use them Mr. Rohde and a team of esteemed scientists and
statisticians developed a new analytical approach that let us incorporate
fragments of records. By using data from virtually all the available
stations, we avoided data-selection bias. Rather than try to correct for the
discontinuities in the records, we simply sliced the records where the data
cut off, thereby creating two records from one.

We discovered that about one-third of the world's temperature stations have
recorded cooling temperatures, and about two-thirds have recorded warming.
The two-to-one ratio reflects global warming. The changes at the locations
that showed warming were typically between 1-2ºC, much greater than the
IPCC's average of 0.64ºC.

To study urban-heating bias in temperature records, we used satellite
determinations that subdivided the world into urban and rural areas. We then
conducted a temperature analysis based solely on "very rural" locations,
distant from urban ones. The result showed a temperature increase similar to
that found by other groups. Only 0.5% of the globe is urbanized, so it makes
sense that even a 2ºC rise in urban regions would contribute negligibly to
the global average.

What about poor station quality? Again, our statistical methods allowed us
to analyze the U.S. temperature record separately for stations with good or
acceptable rankings, and those with poor rankings (the U.S. is the only
place in the world that ranks its temperature stations). Remarkably, the
poorly ranked stations showed no greater temperature increases than the
better ones. The mostly likely explanation is that while low-quality
stations may give incorrect absolute temperatures, they still accurately
track temperature changes.

When we began our study, we felt that skeptics had raised legitimate issues,
and we didn't know what we'd find. Our results turned out to be close to
those published by prior groups. We think that means that those groups had
truly been very careful in their work, despite their inability to convince
some skeptics of that. They managed to avoid bias in their data selection,
homogenization and other corrections.

Global warming is real. Perhaps our results will help cool this portion of
the climate debate. How much of the warming is due to humans and what will
be the likely effects? We made no independent assessment of that.

Mr. Muller is a professor of physics at the University of California,
Berkeley, and the author of "Physics for Future Presidents" (W.W. Norton &
Co., 2008).

Credit: By Richard A. Muller


On 10/21/11 7:48 PM, "r...@llnl.gov" <r...@llnl.gov> wrote:

> "Anthony Watts, a former TV meteorologist who runs the blog "Watts Up With
> That?" and who had initially consulted with Muller on the Berkeley effort,
> took the unusual step of submitting a letter decrying its findings to
> lawmakers before the House hearing where Muller spoke had ended (ClimateWire,
> April 1).
> In a blog post yesterday, Watts said the Berkeley group's decision to publish
> its findings on the Web before they had been peer-reviewed was "troubling." "
> 
> Like non-peer reviewed disinformation by the deniers isn't
> troubling/dangerous? - G
> 
> 
> SCIENCE:
> Koch-backed research effort finds Earth is warming
> Lauren Morello, E&E reporter
> Published: Friday, October 21, 2011
> 
> The Earth's surface is warming, after all, says a team of researchers who
> sought to investigate claims that flawed data and methods had skewed existing
> analyses of global temperature trends.
> 
> The work by the Berkeley Earth Project shows that, on average, global land
> surface temperatures have risen about 1 degree Celsius since the mid-1950s --
> on par with the warming trend described by research groups at the National
> Oceanic and Atmospheric Administration, NASA and the U.K. Meteorological
> Office.
> 
> The Berkeley effort's leader, astrophysicist Richard Muller, said his team had
> taken climate skeptics' criticisms of existing research into account when they
> began to examine global temperature data going back to 1800.
> 
> But in the end, the factors singled out by skeptics -- including some poorly
> sited temperature-monitoring stations -- did not have much bearing on his
> group's results.
> 
> "When we began this, I didn't know whether we would see more warming than
> people had previously seen, or less. I knew that some skeptics had raised
> legitimate issues that needed further study," said Muller, a professor at the
> University of California, Berkeley. "We've done that study now, and I think
> I'm surprised that the results agree with previous groups."
> 
> The Berkeley group published four papers describing its work, its data and the
> programs it used to analyze those data yesterday on its website,
> berkeleyearth.org. The papers have not been peer-reviewed, but Muller's team
> has submitted them for publication in scientific journals.
> 
> Several climate scientists said they weren't surprised that the Berkeley
> group's findings confirmed that the Earth is warming, something they said is
> supported by multiple lines of evidence -- not just the instrumental
> temperature records examined by Muller.
> 
> Skeptics' complaints don't check out
> 
> Asked whether the Berkeley Earth findings were newsworthy, NASA climatologist
> Gavin Schmidt had a simple answer: "No." But Schmidt said he thought the
> method Muller's team devised for analyzing temperature data "does seem to be
> interesting," though he cautioned that it had not been peer-reviewed.
> 
> Similarly, Kevin Trenberth, a senior scientist at the National Center for
> Atmospheric Research, said the Berkeley findings "need some good reviews."
> 
> "It is interesting in many respects," he said. "A good aspect is the
> sophisticated use of statistics. A bad aspect is the overuse of statistics and
> not enough common sense and basic physics."
> 
> Peter Thorne, a climate scientist at the North Carolina-based Cooperative
> Institute for Climate and Satellites, called the Berkeley Earth analysis
> "certainly useful, though ... not particularly novel."
> 
> Having multiple research groups examine temperature records, each with its own
> method, helps reduce uncertainty in scientists' estimate of ongoing warming,
> Thorne said. "I wish there were another 10 groups looking at the problem
> independently," he added.
> 
> Meanwhile, Muller said he hopes his results will convince people who doubt
> whether the Earth is warming that it is indeed happening.
> 
> "We can't win over the deniers," he said. "There are people on both sides who
> grossly exaggerate. But in between, there are a substantial number of properly
> skeptical people. I believe that work we're doing is the sort of work they're
> looking for."
> 
> It's a case Muller makes today in a Wall Street Journal op-ed. "Global warming
> is real. Perhaps our results will help cool this portion of the climate
> debate," he writes.
> 
> But reaction to the Berkeley Earth project has been mixed.
> 
> Before the group released its first set of findings last spring, liberal
> blogger Joe Romm of the Center for American Progress questioned the Berkeley
> group's motives, noting that it had received funding from the Charles G. Koch
> Charitable Foundation, which has supported efforts opposing mainstream climate
> change science.
> 
> And when Muller testified in March before a House committee that his group's
> preliminary analyses supported the overall warming trend reported by
> mainstream climate scientists, some skeptics were enraged.
> 
> Deniers remain in denial
> 
> Anthony Watts, a former TV meteorologist who runs the blog "Watts Up With
> That?" and who had initially consulted with Muller on the Berkeley effort,
> took the unusual step of submitting a letter decrying its findings to
> lawmakers before the House hearing where Muller spoke had ended (ClimateWire,
> April 1).
> 
> In a blog post yesterday, Watts said the Berkeley group's decision to publish
> its findings on the Web before they had been peer-reviewed was "troubling."
> 
> "Is their work so important, so earth shattering, that they can't be bothered
> to run the gauntlet like other scientists? This is post normal science at its
> absolute worst."
> 
> Meanwhile, the skeptic blog "Climate Depot" carried this headline yesterday
> afternoon: "Oh no, not Richard Muller's confused world again!"
> 
> Muller remains unbowed.
> 
> "Watts continues to jump back and forth between loving us and hating us," he
> said. "He has criticized one of our papers in a way that I have looked at. I
> believe his criticism is not valid, but I have not resolved that yet."
> 
> The Berkeley Earth team's focus now is publishing the results of its land
> surface temperature analysis and raising the money to examine records of ocean
> surface temperatures, Muller said.

-- 
You received this message because you are subscribed to the Google Groups 
"geoengineering" group.
To post to this group, send email to geoengineering@googlegroups.com.
To unsubscribe from this group, send email to 
geoengineering+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/geoengineering?hl=en.

Reply via email to