An interesting development regarding the well known global temperature graph with the twentieth century hockey stick like uptick has possibly added another reason for rejecting the accuracy of the graph and with it the alarmism concerning global warming.
To summarize, tree rings have been used as proxies for historical temperature data. What has now been shown by Steve McIntyre is that when a larger pool of tree ring data is included, the hockey stick disappears. Barring reasonable explanations, if this does not kill the hockey stick, then actual science in climates studies is dead.
An important context to all of this is that the data had, until now, not been publicly available. This is contrary to standard scientific journal requirement for the archiving of data. It is rather difficult to peer-review in a meaningful manner when the underlying data or even the program code that assembled the data is unavailable. It took much fighting to achieve this public disclosure, which now allows others to see how much of tree ring data was rejected and the result of including this in the temperature plot.
As CA readers also know, until recently, CRU staunchly refused to provide the measurement data used in Briffa's Yamal reconstruction. Science(mag) acquiesced in this refusal in connection with Osborn and Briffa 2006. While the Yamal chronology was used in a Science article, it originated with Briffa 2000 and Science(mag) took the position that the previous journal (which had a different data policy) had jurisdiction. Briffa used the chronology Briffa et al (Phil Trans B, 2008) and the Phil Trans editors finally seized the nettle, requiring Briffa to archive the data. As noted before, Briffa asked for an extension and, when I checked earlier this year, the Yamal measurement data remained unarchived. A few days ago, I noticed that the Yamal data was finally placed online. With the information finally available, this analysis has only taken a few days.
If the non-robustness observed here prove out (and I've provided a generating script), this will have an important impact on many multiproxy studies that have relied on this study. (source and more here about this, Thanks to AoSHQ)
Be sure to read it all. It is quite technical but the graphs make the situation very clear.
Unfortunately, it seems this unwillingness to allow open examination of methods and data sources is rather common for some in the climate studies field. Despite that, we still have those who claim the science is settled and that we need to do whatever it takes to avoid climate catastrophe.
That we don’t have catastrophic climate change that we must attempt to avoid does not mean that the environment is a free fire zone. Portraying all skeptics of man made global warming/climate change as motivated only by a desire to wantonly rape and destroy the environment is as dishonest as it is mistaken. Instead of attacking skeptics in such fashion, how about the various agencies and scientists have open and honest discussion about the data and methodologies used before we rush into destroying economies and limiting freedoms? Once we’ve gained certainty about the process and data, and determined what really is necessary, there would still be left many discussions about what is actually achievable and what are reasonable tradeoffs to accomplish the goals.
With this additional demonstration of less than professional and sound scientific work underlying the hysteria, what’s the hurry?
A less technical summary of this story for the layman is available at the Bishop Hill blog.
The story of Michael Mann's Hockey Stick reconstruction, its statistical bias and the influence of the bristlecone pines is well known. McIntyre's research into the other reconstructions has received less publicity, however. The story of the Yamal chronology may change that. (source)