EnviroLink Forum

http://www.sciencemag.org/content/339/6 ... 8.abstract


A Reconstruction of Regional and Global Temperature for the Past 11,300 Years
Surface temperature reconstructions of the past 1500 years suggest that recent warming is unprecedented in that time. Here we provide a broader perspective by reconstructing regional and global temperature anomalies for the past 11,300 years from 73 globally distributed records. Early Holocene (10,000 to 5000 years ago) warmth is followed by ~0.7°C cooling through the middle to late Holocene (<5000 years ago), culminating in the coolest temperatures of the Holocene during the Little Ice Age, about 200 years ago. This cooling is largely associated with ~2°C change in the North Atlantic. Current global temperatures of the past decade have not yet exceeded peak interglacial values but are warmer than during ~75% of the Holocene temperature history. Intergovernmental Panel on Climate Change model projections for 2100 exceed the full distribution of Holocene temperature under all plausible greenhouse gas emission scenarios.

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With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none”
Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."
Albert Einstein

Here is another article to peruse;
Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
http://www.skepticalscience.com/Carbon- ... Years.html

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"With every decision, think seven generations ahead of the consequences of your actions" Ute rule of life.
“We do not inherit the earth from our ancestors; we borrow it from our children”― Chief Seattle
“Those Who Have the Privilege to Know Have the Duty to Act”…Albert Einstein

Lets have a look at some of the facts surrounding this study. Shaun Marcott is a very inexperienced first year PhD. from Oregon State University. Who in the past has publically stated when asked about Mann et al., “Its not robust.” Marcott’s study is a proxy based model smoothing study using 73 sample marine sites that claims to cover 196 million square miles and 11,300 years. Only 73 marine sites that seem to me would proxy ocean temperatures rather than atmosphere temperatures. Now something doesn’t pass the smell test about this. Marcott et al was published according to the link provided on March 8th. A Friday. But Seth Borenstein of AP published a story about this paper on March 7th.

http://talkingpointsmemo.com/news/recen ... -years.php

Something else kind of stinky here. Justin Gillis New York Times on March 7th.

http://www.nytimes.com/2013/03/08/scien ... .html?_r=0

“In the new research, scheduled for publication of Friday (March 8th) in the journal Science.”

Again a day before the release in Science. This is a coordinated effort by all involved here. Two articles written a day before release with details about the study before it was published. This amounts to tabloid climatology. Oh but it gets better. Marcott et al have yet to release any data or materials regarding this paper. Taking advice from Dr. Mann? From the March 12th National Journal.

“Marcott admitted he was apprehensive about charging into the fully-mobilized troll army...” Oh, he sounds like an objective man of science only concerned with the truth doesn’t he?

But wait it gets even better. This study appears to be based upon Marcott’s thesis paper. But, there are key differences in the conclusion of both. First graph is from the thesis.


Second graph is from the released study.



A hockey stick magically appears. This is climate science by press release, pal review, and Science, the AP, and the New York Times promote it as peer reviewed when the researcher refuses to turn over data and material so someone else can attempt to repeat it. This study is no more than a glorified press release. Embarrassing at most. At the least proving this researcher has serious problems with his methodology.

Obama has failed with the carbon tax, cap and trade, but James Hansen said in 2008 that Obama has four years to save the planet. The UN issued another tipping point in 1989. 10 years. Both have passed and we are still here. This movement is a joke. No one believes you. Your desperate. I knew this cause was in trouble when it began to make absolutely everything imaginable was the fault of climate change. At this point the theory ceases to be falsifiable. It has become political theory so it becomes whatever the politicians want it to be. It is certainly not science.

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Potato chip enthusiast.

When you have to leap to a conspiracy theory in science in order to try to discredit a paper, you really need to just give it up.

Even WUWT disagrees with you on the data being available.

_________________
With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none”
Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."
Albert Einstein

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Potato chip enthusiast.

I thought you were more learned and intelligent. I guess not with science. Besides spending some time at Skeptical Science , try out this, too;

http://wottsupwiththat.com/



and this one. Now pay attention, Milton.
http://www.wunderground.com/climate/PETM.asp

_________________
"With every decision, think seven generations ahead of the consequences of your actions" Ute rule of life.
“We do not inherit the earth from our ancestors; we borrow it from our children”― Chief Seattle
“Those Who Have the Privilege to Know Have the Duty to Act”…Albert Einstein

_________________
With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none”
Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."
Albert Einstein

I think that the conclusions in the Marcott et al. 2013 should be revised to indicate that the 20th Century uptick that many blogs were concerned about was not statistically robust.

It's an interesting analysis for the Holocene Warm Period, but to focus on the 20th Century uptick of the reconstruction doesn't make much sense when the authors themselves confirmed that the uptick in the 20th Century was not statistically robust.

_________________
With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none”
Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."
Albert Einstein

Note the rate of temperature change was the point of concern with the robustness of the data, not that the modern instrumental record compared to the reconstructed temperature record showed a change from the lowest temperature to nearly the hottest temperature during the past 11,300 years.

Q: Is the rate of global temperature rise over the last 100 years faster than at any time during the past 11,300 years?

A: Our study did not directly address this question because the paleotemperature records used in our study have a temporal resolution of ~120 years on average, which precludes us from examining variations in rates of change occurring within a century. Other factors also contribute to smoothing the proxy temperature signals contained in many of the records we used, such as organisms burrowing through deep-sea mud, and chronological uncertainties in the proxy records that tend to smooth the signals when compositing them into a globally averaged reconstruction. We showed that no temperature variability is preserved in our reconstruction at cycles shorter than 300 years, 50% is preserved at 1000-year time scales, and nearly all is preserved at 2000-year periods and longer. Our Monte-Carlo analysis accounts for these sources of uncertainty to yield a robust (albeit smoothed) global record. Any small “upticks” or “downticks” in temperature that last less than several hundred years in our compilation of paleoclimate data are probably not robust, as stated in the paper.

_________________
With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none”
Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."
Albert Einstein

_________________
With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none”
Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."
Albert Einstein

Let's see, the concern over the robustness of the reconstruction being able to tell us about the rate of temperature increase is moot since the paper did not make such a determination.

The next concern over the variability of the proxy measurements from different location in the determination of a global temperature is unrelated to any known science issue.

Maybe the third concern will fare better.

_________________
With friends like Guido, you will not have enemies for long.

“Intellect is invisible to the man who has none”
Arthur Schopenhauer

"The difference between genius and stupidity is that genius has its limits."
Albert Einstein

You might be interested in this paper Wayne:

http://www.nature.com/nature/journal/v4 ... 11969.html

They claim that current warm temperatures in the Arctic regions are unprecedented over the last 600 years, which may or may not be true. The paper is behind a paywall, so I'm not able to access the full paper and see the data, so I'll remain neutral about this paper for now. It's also not surprising that it shows that the Arctic Temperatures are the warmest in 600 years, since the warming period in question, the MWP, was not included in the timeframe of analysis in the paper. My main interest is the causes of climate change over the last 150 years and how sensitive the climate is to an equilibrium doubling of CO2. The sharp warming over the last 150 years or so has likely had a significant solar component to the warming, even when assuming that the Hockey Stick Proxies are correct, like did.



Interestingly, they get a very nice correlation between solar activity and the temperature when they used mostly hockey stick reconstructions. Even more interesting is that Usoskin, Solanki and the other authors of the paper are proponents of the "mainstream" Anthropogenic Global Warming hypothesis. Yet, they found that solar activity can explain at least a sharp 0.3-0.4 Degree C increase (roughly) during this most recent warming episode.

The next image is from . This paper shows the intricate correlation between solar activity and temperature over the last 2000 years even more closely. Again, note the dramatic increase in solar activity over the 20th Century in Solar Activity.



Solar Activity rising substantially and pretty dramatically during the 20th Century can explain a large portion of the sharp warming during this period. Of course, while the anthropogenic contribution is also significant, the Solar Forcing is one that can not be ignored.