Posted on 06/28/2006 10:53:23 AM PDT by Enchante
Last week's release of a National Academies of Science (NAS) report entitled "Surface Temperature Reconstructions for the Last 2,000 Years" was the result of a congressional request to look into the controversy surrounding the now-famous "hockey stick" temperature curve. The media portrayed the findings of the NAS review panel as some sort of new statement about how warm the Earth is at present, and totally missed the real news: that the original claim of Mann et al. of unprecedented warmth in the last 1,000 years -- based mostly upon tree ring data, especially from the southwest U.S. -- was dubious at best.
For the last several years, the hockey stick has been a poster prop for manmade global warming. For instance, it figures prominently in Al Gore's new movie, "An Inconvenient Truth." But the statistical and data analysis methods that Mann et al. used to arrive at their 1,000 year temperature reconstruction were strongly criticized by some. The hockey stick played down the warmth of the "Medieval Warm Period" of 1,000 years ago, as well as the later coolness of the "Little Ice Age."
Also, the uncritical acceptance of the hockey stick for inclusion in the U.N.'s Third Assessment Report on global climate in 2001 gave many scientists the impression that the editors of that report wanted to believe the hockey stick more than they were convinced of its validity.
In their attempt to not publicly scold Mann and his coauthors for questionable data analysis methods, the authors of the new report instead chose to restate the evidence for how warm the Earth has gotten recently. What the media didn't notice, however, is that the 1,000 year figure that was central to the whole hockey stick debate had now been replaced in the report by a figure of 400 years. Since most of the last 400 years was dominated by the "Little Ice Age," the warming during the 20th century should be welcomed by humanity.
The report says that surface temperature reconstructions before this period (about 1600) have "less confidence" and that "uncertainties...increase substantially backward in time..." for any of these proxy estimates of ancient temperatures. One review panel member told me that the statisticians on the panel were amazed when it was revealed that the method underlying the hockey stick had essentially no statistical skill when validated.
This is pretty harsh language for an NAS report written by review panel members, several of whom are equivalent to foxes guarding the hen house. Researchers who have bought into the validity of using proxy measures for ancient climate reconstructions aren't about to throw away the "best" method the paleoclimate research community has, even if it can not be validated with real temperature measurements (the thermometer was not even invented until the 1600's).
One rather amazing characteristic of the hockey stick is the so-called "divergence problem": the strong warming in the late 20th century is not even indicated in the tree ring data that were used to reconstruct the last 1,000 years of supposed temperature variations. Much of the 20th century warming (the blade of the hockey stick) represents real temperature measurements, not tree ring reconstructions, since they don't show the warming. This raises a natural question, which the panel shrugged off: If tree rings do not show the strong warming of the late 20th century, how do we know there wasn't a similar temperature spike 1,000 years ago?
Keeping the door open to the possibility that Mann might be right anyway, the new report says that it is at least "plausible" that we are warmer now than anytime in the last 1,000 years. But this is a much lower level of certainty than has been associated with the hockey stick by the media, bureaucrats, and movie stars (like Al Gore).
But what was the biggest news in the media coverage of the NAS report last week? The biased nature of the media coverage. It almost seems like the media covering the report looked for familiar phrases that fit their global warming paradigm (e.g., "...warmer than the previous 400 years..."), without noting the important conclusions that addressed why the report was written in the first place.
Indeed, much of the press coverage managed to connect the words "warmer than" with a report reference to "2,000 years" to come up with widespread statements (not supported by the report) that the Earth is warmer now than when Jesus Christ walked the Earth. Apparently, sound bites are still preferred over truth.
The NAS review panel report admits that it is difficult to conclude that we are warmer now than 1,000 years ago, but that we are very likely warmer than anytime in the last 400 years. Since what this really means is that we are warmer now than any time during the "Little Ice Age" (and thank goodness for that), one wonders whether we really know anything about past climate reconstructions from tree ring data.
Dr. Roy Spencer is a principal research scientist for the University of Alabama in Huntsville and the U.S. Science Team Leader for the Advanced Microwave Scanning Radiometer (AMSR-E) on NASA's Aqua satellite.
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Actually I think "Fraud" is more accurate than "Junk Science"...
Maybe the Democrats are going to run on Kyoto this year, there seems to be a convergence. It's the perfect Democrat issue, big corporate bucks cloaked in a sheen of altruism, this time environmentalism.
How about "Corrupt" science.
My letter to the NAS:
Since in your statement that “it is warmer now than anytime in the past 400 years” you did not say that it got really cold sometime between 1200 AD and 1600AD as indicated by the archeological findings in Greenland, the Viking writings and other historical records, that I have been seeing on the history channel and reading in Archeology magazines. See below:
http://www.museum.state.il.us/exhibits/ice_ages/when_ice_ages.html
But what the anti-American press will use your findings for, which they have already done, is to say it is warmer now than in the past millennium(s), will be to say a lie and that lie is that humans are responsible for the natural cycles of warm and cold of this solar system. The Vikings had to leave Greenland because of a climate change that went very cold as proven by archeological digs in Greenland, and the Viking Chronicles, this was of course before it started to get warm again sometime around 1600 AD.
Why do you add to the unscientific fabrication that we humans are responsible for the natural cycles of the earth and sun? It sure did get warmer for the last 400 years, if that were not so we would be living with the ice coming down upon us. Thank you nature for the warming.
Judging a "trend" in the Earths climate for the last 2000 years out of hundreds of thousands is absurd. Thats just .4% of the last 500,000 years. We have been through numerous cold periods and warm periods in that time. That would be like looking at a 75 year old man and judging his overall health by the last 3 years of his life.
Chery picking data is being done by both sides of this debate.
More like the last 3-4 months!
"More like the last 3-4 months!"
Corrected, thanks, I missed a decimal place.
Even more to my piont though.
Thats POINT, not piont.
Reverse Scientific Method 1)Draw your conclusion. 2)Select data,no matter how flawed,to support your conclusions. 3)Discard any data,no matter how valid,which does not.
I call it "Brave New Science"
How about Algorical data?
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Simpler version: 1) Shoot arrow; 2) Draw Bullseye around arrow.
Seems that only one side is cheery picking in an effort to promote global government.
Guess which side?
Seems that only one side is cheery picking in an
effort to promote global government.
And one side cherry picking to protect profit margins.
Not only cherry picking the data, whenever you have a long data series with lots of variation, it is very easy to do different levels of regression to get the smoothed trendline that you want.
Mcintyre's criticism of the statistical method used by Mann in his hockey stick shows how just applying different regression techniques can turn data from completely flat with some random noise into a hockey stick.
The tree ring data used by Mann was recently updated with much more tree ring samples. Mcintyre posted the simple average of this data versus using Mann's technique on his website yesterday.
Have a look, and be prepared to go WTF.
http://www.climateaudit.org/
I think that the significance of this report is that it undercuts the controversial "hockey Stick" graph, which had been featured in IPCC 2001. The "hockey stick" graph had eliminated climate fluctuations of the past, such as the Little Ice Age (LIA) and the Medieval Warm Period (WMP). The MWP occurred about 1000 years ago when the Vikings colonized Greenland. We Skeptics believe the WMP was as warm (or warmer) as today. With the WMP erased, alarmists could declare today's temperatures unprecedented - thereby strengthening their case for anthropogenic warming.
The report (page 3) found Mann’s hockey stick ‘plausible’ ( support couldn't be weaker) On the top of page 4 the report says that substantial uncertainties prior to about AD 1600 lowers their confidence in the hockey stick. In the next line the report says “Even less confidence can be placed in the original conclusions by Mann et al. that ‘the 1990s are likely the warmest decade, and 1998 the warmest year, in at least a millennium’.” This language is certainly not validating hockey stick as some popular press articles state.
With respect to the criticisms of Mann's questionable statistical methods, the report says (page 107) “Some of these criticisms are more relevant than others, but taken together, they are an important aspect of a more general finding of this committee, which is that uncertainties of the published reconstructions have been underestimated."
Call this a victory for sanity in climate science!
Really? Seems all the big oil companies have signed on to the junk science bandwagon too. It's the PC thing to do.
It is not corporate profits that will slump if the Gorebots have their way. It is the American people who will see their standard of living drop like a rock.
The Global Warming dabate is framed by Liberals as being between concerned dedicated environmentalists on one side and evil capitalistic profit-hungry big business on the other side.
Of course Liberals will then disregard anything said by the later side, no matter what.
Unfortunatly it appears neither side is listening.
There are vested interests on all sides of the debate. Use a grain of salt when concidering any argument that holds an extreme on either side.
Has any real Climate Scientist not known about the flawed methods used to create the "Hockey Stick"? This is not exactly news.
Re: Little Ice Age. What was the concentration of CO2 in the atmosphere then?
A very interesting, but deep, site.
One winter when money was tight I convinced my wife that turning the thermostat down wouldn't make her feel cold; when that didn't work, I adjusted the kitchen thermometer to read 3 degrees higher than the actual room temp, she quit complaining, but I'm not sure she was convinced.
In another case, I had a woman who was forever wanting me to climb the stairs to adjust the temp because it was cold at her desk; one evening after she left work, I installed a dummy t-stat on the wall and she was so happy the next morning she called me to thank me for making it warmer.
Only the ice-core fairies know.
My question...If Greenland is now a glacial sheet...how did it manage to be inhabited...with agriculture in the past?
Roy Spencer makes interesting reading. Unfortunately (in the eyes of global warming alarmists) he has three big strikes against him. The TCS site in which he posts is partially funded by Exxon. He believes in God. He believes in Intelligent Design. So despite his education and his awards, any one one of those three things automatically bring into question, among global warming alarmists, anything he has to say on the subject. And all three together? Global alarmists will write him off as a crackpot being paid by the oil industry.
I have a friend in building maintenance that has the same story. Showed me the t-stat. Must be a common solution.
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