Tuesday, March 30, 2010

Eli can retire 1

Thanks to Marcus, Eli has a ready source of pre-written posts, the EPA Endangerment Response to Comments. The rest of you keep your hands off.

Comment (2-4):
A commenter (0740.1) states that ice core CO2 measurements are impacted by water contamination, and that there are no other methods of measuring historical CO2 (commenter 3722 also objects to ice core record manipulation). Several commenters (0339, 0714.1, 2210.5, 3722) have cited either Beck (2007) or Jaworowski to support a contention that CO2 was at high concentrations in the recent past immediately before the Mauna Loa record started, or during past interglacials (0655).

Response (2-4):
We disagree with the assertion by several commenters that estimates of historical CO2 concentrations are incorrect. According to IPCC (Jansen et al., 2007), “it is possible to derive time series of atmospheric trace gases and aerosols for the period from about 650 kyr [thousand years] to the present from air trapped in polar ice and from the ice itself.” This methodology has been “verified against recent (i.e., post-1950) measurements made by direct instrumental sampling.” Additionally, these measurements are consistent with various less accurate methods such as using the size of stomatal pores on tree leaves, boron isotope measurements in plankton buried under the ocean, or carbon isotope ratios in algae buried in the ocean floors, moss samples, and foraminefera carbonate shells. Therefore, there is extremely high confidence in the CO2 values determined from the ice core records, and we disagree that there is any evidence that water contamination or other manipulations reduce the confidence in the ice core estimates.

The commenters cited a theory from Jaworowski that water contamination in the ice core record reduces its reliability, and that the IPCC CO2 historical estimates require shifting the ice core records an arbitrary number of years in order to make them line up with the instrumental record. The critiques of Jaworowski on the shift were addressed by Hans Oeschger (1995), who pointed out that the ice core record shift was done in accordance with theoretical estimates of the rate of diffusion in gases in firn, and that these theoretical estimates were confirmed by isotopic enrichment in line with theory. Güllük et al. (1998) also rebutted Jaworowski on contamination, stating that “Jaworowski et al. [1992, 1994] suggested that CO2 measurements may be subject to fractionation due to clathrate formation and destruction. The good agreement of our CO2 measurements with those made by LGGE using the milling extraction procedure makes this artefact unlikely.” Similarly, Raynaud et al. (1993) found that the objections by Jaworowski were unfounded, demonstrating that the changes in CO2 and methane (CH4) are similar for different interglacial periods, regardless of depth, and that ice cores from different locations give the same values regardless of different “brittle zone” conditions between the different locations.

With respect to the citations of Beck (2007) and Jaworowski (1992, 1994) on pre–Mauna Loa CO2 records, these papers rely on chemical measurements that were taken in many environments which were not far enough away from sources and sinks of CO2 in order to measure the background concentration.

Beck himself (2007) notes that many of his measurements were taken from the “periphery of towns” and shows temporal CO2 plots that have large (210 ppm) variability over a time period of two months. He recognizes that some of these data points need to be corrected by 10 to 70 ppm to take into account nearby cities. This large variability is in contrast to the relatively smooth year after year increase in the Mauna Loa and other modern instrumental records. The pattern of CO2 changes in the Mauna Loa records are much more consistent with the ice core records than with the Beck estimates. Therefore, we find that these historical CO2 estimates by Beck and Jaworowski are not reliable alternatives to the conclusions of the assessment literature on historical background CO2 levels.

Therefore, EPA has determined that the assessment literature estimates of historical CO2 concentrations over the past 800,000 years are of high quality and the most reliable estimates available.
Easy blogging

7 comments:

Anonymous said...

thank you, now I can again trust medicines to contain what they say, don't they use the same methods in those controls?

Cthulhu said...

woa that is like 100 years of blog posts right there

John Mashey said...

There really ought to be a terse web page somewhere, with a list of truly awful papers, so that folks like the EPA could say:

"Send comments, but if you favorably reference any of this list of papers, we will simply ignore it, except to post it on a website for dumb submissions."

EliRabett said...

True, and Eli intends to go through the comments to pick out the juicy ones. Beats working

Anonymous said...

Eli must “retire”;
Beck wrote in 2009 a new paper with Massen (Accurate estimation of CO2 background level from near ground measurements at non-mixed environments) and introduced a new graph: I will add it

... and another objections to the ice core : Does Algae Reduce the Ice Core CO2?, ICE Core CO2 Records - Ancient Atmospheres Or Geophysical Artifacts ?

Anonymous said...

By the way for example you know that:

- A bacterial ice-binding protein from the Vostok ice core, James A. Raymond, Brent C. Christner and Stephan C. Schuster, 2008.:
“A bacterial strain recovered from glacial ice at a depth of 3,519 m [!], just above the accreted ice from Subglacial Lake Vostok, was found to produce a 54 kDa ice-binding protein (GenBank EU694412) that is similar to ice-binding proteins previously found in sea ice diatoms, a snow mold, and a sea ice bacterium. The protein has the ability to inhibit the recrystallization of ice...

- A Survivor in Greenland: A Novel Bacterial Species is Found Trapped in 120,000-Year-Old Ice:
“3 June 2008 — A team of Penn State scientists has discovered a new ultra-small species of bacteria that has survived for more than 120,000 years within the ice of a Greenland glacier at a depth of nearly two miles [...].
“This new species is among the ubiquitous, yet mysterious, ultra-small bacteria, which are so tiny that the cells are able to pass through microbiological filters.
“The ultra-small size of the new species could be one explanation for why it was able to survive for so long in the Greenland glacier. Called Chryseobacterium greenlandensis ..."
“The organism is one of only about 10 [!] scientifically described new species originating from polar ice and glaciers.”.

A similar work is already more than 100 ...
Arkadiusz Semczyszak

Marco said...

Seriously, Arkadiusz?

Let me point out first that Beck and Massen in their new paper still fail to explain how the CO2 in the atmosphere suddenly goes 'monotonic' upwards from the time we started measuring on Mauna Loa. Do you think this is a Mauna Loa issue? Think again, it has been measured on many different places, including on Antarctica, thousands of kilometers away from any active volcanoes.

And then there's your link to bacteria. A whole post on a blog trying to claim CO2 may be decreased by bacteria. No mechanistic explanation, just linking the two. But there is an interesting claim that the bacteria live in an oxygen-free environment. Too bad that that is wrong, there IS oxygen in the gas bubbles. Hmm...what to do. Believe someone with an unsubstantiated claim, or note the contradictions in his argumentation and reality?

Oh, and you might want to know that the protein that inhibits ice crystallization is INSIDE the bacteria. It's the reason it can survive in such cold temperatures. Note that they are essentially in stasis at freezing temperatures.