Skip to comments.A Global Temperature History of the Past Two Millennia [PEER-REVIEWED!!! WITH SOURCE!!!]
Posted on 01/29/2008 11:13:13 AM PST by E. Pluribus Unum
Download original article here.
A Global Temperature History of the Past Two Millennia
Loehle, C. 2007. A 2000-year global temperature reconstruction based on non-treering proxies. Energy and Environment 18: 1049-1058.
What was done
Using data from eighteen 2000-year-long proxy temperature series from all around the world that were not developed from tree-ring data (which provide significant interpretive challenges), the author (1) smoothed the data in each series with a 30-year running mean, (2) converted the results thereby obtained to anomalies by subtracting the mean of each series from each member of that series, and then (3) derived the final mean temperature anomaly history defined by the eighteen data sets by a simple averaging of the individual anomaly series, a procedure that he rightfully emphasizes is "transparent and simple."
What was learned
The results obtained by this procedure are depicted in the figure below, where it can be seen, in the words of its creator, that "the mean series shows the Medieval Warm Period (MWP) and Little Ice Age (LIA) quite clearly, with the MWP being approximately 0.3°C warmer than 20th century values."
What it means
Loehle notes that "the 1995-year reconstruction shown here does not match the famous hockey stick shape," which clearly suggests that one of them is a poorer, and the other a better, representation of the truth. Because of its simplicity and transparency, as well as a host of other reasons described in detail by Loehle -- plus what we have learned since initiating our Medieval Warm Period Record-of-the Week feature -- it is our belief that Loehle's curve is by far the superior of the two in terms of the degree to which it likely approximates the truth.
Reviewed 30 January 2008
So you know and I know, but how do we get past the steel bars of the MSM cage and get the message public? What to use as a hacksaw so to speak?
I’ll pass this on to many, but that is a few only, and many of those folks will look at this, their eyes will glaze over, and the delete button will serve its purpose.
But what about the shrinking Polar bear testicles?
Dont be silly that is no longer acceptable per PC rules. We must tie a stone to him and through him in a pond.
This is the key statement near the end which allows both that previous data still need to be compared to the authors’ methods and that this study, like all scientific studies that are not biased by agenda, are merely signposts on a roadmap that will lead to the true destination.
“While instrumental data are not strictly comparable, the rise in
29 year-smoothed global data from NASA GISS (http://data.giss.nasa.gov/gistemp)
from 1935 to 1992 (with data from 1978 to 2006) is 0.34 Deg C. Even adding this rise
to the 1935 reconstructed value, the MWP peak remains 0.07 Deg C above the end of
the 20th Century values, though the difference is not significant.
The main significance of the results here is not the details of every wiggle, which
are probably not reliable, but the overall picture of the 2000 year pattern showing the
MWP and LIA timing and curve shapes. Future studies need to acquire more and
better data to refine this picture.”
Chinese records of sunspot activity go back to around 800 BC, although spotty (no pun intended) and incomplete. But according to another article, tree rings have also recorded sunspot activity and can be used to track them back to the last ice age.
Trees and tree rings contain carbon, which they get from carbon dioxide in the atmosphere. Some of that carbon is the isotope carbon-14, which is created in the Earth's atmosphere by cosmic rays flying in from outside the solar system.
But those cosmic rays can't reach Earth when the Sun is stormy with sunspots and the solar wind is roaring. So a tree ring containing low carbon-14 is a sign of few cosmic rays in that growth year. This is an indicator of a stormy Sun, said researchers led by Professor Sami Solanki from the Max-Planck Institute for Solar System Research and colleagues.
cogitator needs to add this to his archive.
Not necessarily. Does he weigh the same as a duck?
Who knew you were so wise in the ways of science!
Oh good grief. Something has got to give about what "scientists" are willing to conclude from tree ring data. How can we put these presumptions to the test? Could not the carbon have been high for some other reason?
TO READ LATER, THX
Science used to be hard. Now, thanks to Al Gore, and the IPCC, it's really easy. Just decide how much you want to raise taxes, enter that number into the patented Climate Change Computer model, and volia, multiple climate horror stories guaranteed to open the wallet of even the tightest skin flint. No more late nights in the lab. No more pesky peer review. The Global Climate Change Computer does it all for you.
But the more data (as long as it is properly analyzed and reviewed), the clearer the overall picture.
The scientific consensus is already in.
No further data is required.
Carbon-credit brokers, start your money-churns!
CO2 is plant food. It's where trees get pretty much all their carbon from. Think back to your high-school biology class, where you learned that aside from a few trace nutrients all a plant needs is water and air to grow.
Sounds like an ad hominem attack, to me.
So Mann's hockey stick is still the gospel according to Algore, eh?
Yep, sure is. But I'm not sure what your point is, or maybe you didn't get what mine was.
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