The methane problem

I saw a complaint somewhere that there was too little science talk here and I promised Billy to demonstrate what the problems were with methane as greenhouse gas. So maybe combine the two.

Apart from pure physics, why for greenhouse effect, changes in lower concentrations CH4 are much more important than changes in higher CO2 (logarithmic relationship), we also have the ice cores from the past, with reconstructions of greenhouse concentrations and temperature.

Now check out Liu et al 2012

They are not the first to put question marks by a much warmer Younger Dryas. Check for instance the publications mentioned below. I also fully agree that about changes in isotope ratio due to changing atmospheric conditions but I guess that battle is still ahead, but I'm working on it.

Now comes the problem. Liu et al do not mention methane/CH4 at all, or my search function must have failed. However one of the reasons to assume that the Younger Dryas was so cold is the perfect match of the methane (C and D) with the Greenland isotopes (A) as can be seen here:

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So if Liu et al guessed right as well as the pubs below, then it was not the loss of methane greenhouse effect that caused the cooling, because there was not much of a cooling going on. But if methane is such a strong greenhouse gas, then how about carbon dioxide?


Some publications challenging a cold Younger Dryas

Ager T.A. 2003, Late Quaternary vegetation and climate history of the central Bering land bridge from St. Michael Island, western Alaska Quaternary Research, Volume 60, Issue 1, July 2003, Pages 19-32

Björck, S., Bennike O., Rosén P., Andresen C., Bohncke S., Kaas E., Conley D., 2002. Anomalously mild Younger Dryas summer conditions in southern Greenland. Geology May, v. 30; no. 5; pp. 427–430.

Lohne, Ø. S., S. Bondevik, J. Mangerud, J. I. Svendsen, 2007. Sea-level fluctuations imply that the Younger Dryas ice-sheet expansion in western Norway commenced during the Allerød, Quaternary Science Reviews 26 (2007) 2128–2151

Lücke, A. Brauer A., 2004. Biogeochemical and micro-facial fingerprints of ecosystem response to rapid Late Glacial climatic changes in varved sediments of Meerfelder Maar (Germany). Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 211, Issues 1- 2, 19 August.

Walters, K.A. 2012 Laurentide Ice Sheet Behavior During The Younger Dryas: A Working Hypothesis And Implications Paper No. 28-6 2012 GSA Annual Meeting in Charlotte (4–7 November 2012)

 

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Hmm no tar and feathers today?

Let's see some of those refs, the last one for instance, Kent.

Incidently Lucke and Brauer 2004 reported it also for central Europe:

And all this while the methane concentration had dropped dramatically from about 750-800 ppbv to 400-450 ppbv. which gave the Younger Dryas the reputation of "big freeze". Not! One may wonder why.

A possible key to that is in the Two Creek glacial readvance, which was one of the first carbon datings that Libby did in 1950 and also mentioned by Kent:

Originally Libby had not much choice but to assume that the [sup]14[/sup]C ratio to normal [sup]12[/sup]C in atmospheric CO2 had been constant all the time, which is essential for carbon dating. Meanwhile Willi Dansgaard develloped the ice core techniques in the early 1970's, in Dye and Camp Century. I have not been able to put the finger on it, but at some time the beginning of the Younger Dryas was counted in the ice cores around 12,8 thousand years in annual layers, while the Two Creek glacial readvance was dated at 11.8 [sup]14[/sup]C years. That could have seemed a reasonable match. Somewhat later in the 1980s, the carbon dating proved to be inaccurate with as mean reason, the variation in atmospheric [sup]14[/sup]C. It needed calibration, and now we know that there was a 2000-3000 degree calibration error during the late glacial, and then the Two Creek event went to 13.7 thousand years, well before the Younger Dryas.

Incidently that's also close to the glacial readvance implied by Lohne et al 2007.

So it looks like the 'warm' Allerød was the big Freeze instead. But in that period the methane concentration was high.

It looks like we have a problem.

 

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Apart from pure physics, why for greenhouse effect, changes in lower concentrations CH4 are much more important than changes in higher CO2 (logarithmic relationship), we also have the ice cores from the past, with reconstructions of greenhouse concentrations and temperature.

Could you rewrite that so it makes more sense.
What is your point?

 

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I'm not 100% sure and post my understanding of Andre's point so he can correct it if wrong:

Here is start of liu's abstract (quoted in the OP):
" Greenland ice-core δ18O-temperature reconstructions suggest a dramatic cooling during the Younger Dryas (YD; 12.9–11.7 ka), with temperatures being as cold as the earlier Oldest Dryas (OD; 18.0–14.6 ka) despite an approximately 50 ppm rise in atmospheric CO2. Such YD cooling implies a muted Greenland climate response to atmospheric CO2, contrary to physical predictions of an enhanced high-latitude response to future increases in CO2."

I.e. it is a puzzle (Ignoring CH4) why it got so cold quickly when CO2 rose 50 ppm. I think Andre is suggesting that the GH action of FALLING methane concentrations could be the answer. I.e. because CH4 is so much stronger GHG than CO2, the cooling associated with "lower concentrations CH4 are much more important than changes in higher CO2" to quote Andre, could more than offset the warming of the increased CO2.

Andre, IMHO, is something of a researching climate expert, or at least as close to one as we are likely to get posting here. I am just a climate history ignorant physicist, but very concerned about the rapid increase in CH4 world is now experiencing. It is being released so rapidly that it is INCREASING its half life in the atmosphere. That was a decade or so ago less than 10 years and now is more than 10 years. This is due to the fact the main destruction, at least at altitudes where harsh UV does not get down to, is by chemical reaction with the limited supply of OH- radical which is also destroyed in the reaction.

I don't know much about why there is OH- in the lower atmosphere - i.e. how it is created but the concentration of it seems to be falling and that means the CH4 now bubbling up in dense "sonar- killing" clouds in the Artic Ocean, will survive ever longer on average. It is conceivable to me, that mankind is already beyond the point of no return. I.e. CO2 + CH4 release rates are so much greater than ever before in Earth's history that we are already in positive feed-back, thermal increase, loop with greater than unity gain.

If that is true, then total rain fall and atmospheric humidity will increase. It does seem to be the case that more violent storms, and more common and extreme floods are happening. If (or should I say when?) the wet bulb temperature is about 35C, most humans will die as they produce heat at rate of ~100W, even just resting. Doing significant work, increases that heat production. It must be given to the environment or you die. Normal natural evaporation from your 37C skin can not do that. Some rich will live in air conditioning, but the energy the air conditioners require, will just accelerates the positive feed back as most of it comes from burning fossil fuels. Even the rich can not live long with unburied bodies accumulating.

 

I am afraid that I missed to make my point. Here it is:

The Younger Dryas was relatively warm not cold, while the methane concentration was low.
The Allerod was relatively cold, not warm, while the methane concentration was high.

Apparantly methane (re)acted with a negative greenhouse response.

But the confusion is worsening when we get into the "Mystery Interval"

 

Andre concludes post 2 with: "It looks like we have a problem." I hope he is wrong, but I have been screaming for switch to Sugar Cane alcohol fuel for more than 5 years as I fear he is correct. There is no reason (except oil company profits) not to do this NOW. The entire world's needs for liquid fuel can be produced with no more than 3% of the world's arable land producing sugar cane. Food and fiber production could be increased more than 10% on the remaining, 97% just by simple modern agricultural practices being used more.

 

Now you do have me confused. This seems to be the exact opposite of your OP comments:
"Liu et al do not mention methane/CH4 at all, or my search function must have failed. However one of the reasons to assume that the Younger Dryas was so cold is the perfect match of the methane (C and D) " I.e. the CH4 concentrations shown in curves C & D do fall sharply in the YD. Does not that imply that the GH warming, caused by CH4, that existed just before the YD is decreased?

I now understand that your "It looks like we have a problem." was not what I first thought but related to:
"So it looks like the 'warm' Allerød was the big Freeze instead. But in that period the methane concentration was high."

How strong is the evidence that "the 'warm' Allerød was the big Freeze instead." is true?

 

I'm sorry Billy, I'm afraid that we have to differentiate between several different points of view.

A. what actually happened in the geologic past

B. what we think that happened in the geologic past

C. what we want that happened in the geologic past to suit our agenda's

I'm only interested in getting A and B identical with as a result the occasional witchhunt of the C-ers whenever B and C do not concur.

 

I doubt we will ever get wide spread agreement that "X's" B is identical with A. Hell, when can't even get much agreement even on what is the true A now, much less in the geological past.

Thus I strongly support a switch to sugar cane based fuel, as something that may be essential (given the current alternatives available* to oil) as a conservative safety measure that will at least be beneficial, even if it is only a cheaper alternative (current solar based rather than the limited solar energy stored in fossil fuels, long ago). Also in poor countries, with little skilled labor, cutting cane is a job many currently unemployed can do, earning money to buy higher tech products from more advanced countries to the benefit of both.

Can you clearly state what I your "B" POV? (and also what it implies about current GHG problems, if anything.)

* Ones economically viable for the masses - not $100,000 Tesla electric cars, etc.

 

Obviously the big problem is that the isotopes of the ice cores (as well as in other proxies) between Antarctica (B) and Greenland (A) do not match. So if you assume that these isotopes represent global temperatures, you have a mismatch especially in the Allerød that codates with the Antarctic Cold Reversal ( indicated with ACR in the graph). You'd have to struggle by selling that to sceptics.

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Now Liu et al, and the other pubs I mention demonstatre that the Younger Dryas was warmer than assumed and the Allerød was colder than assumed. Apparantly the Greenland isotopes are not a good paleothermometer.

Notice that the Antarctic isotopes (B) do concur with both these observations hence Antarctic cold reversal is also the Allerød cold reversal and the Younger Dryas is the recovery from that. Apparantly the Antarctic isotopes are a much better as a global paleothermometer. But why then are the methane values not in line at all with these observations.

Here is another one:

humid conditions with cooler summers = Allerod

They proceed hastily to explain their anomaly away with modelling, however, it's not an anomaly, it's how it was.

 

Hmm, I'm suspicious of clichés about "oil company profits". What you mean, surely, is that producing the world's liquid fuel from sugar cane would cost more than from petroleum. If so, the blocker is not "oil company profits" but the resistance of consumers (including you and me) to paying a higher price than they do today. That's how markets work, I'm afraid.

Oil companies are perfectly happy to replace the cheapest energy source by a more costly one, if this is legally mandated and thus not a source of competitive disadvantage for any of them. The whole history of transport pollution control shows this. So if you want action, persuade your government.

 

So the big mystery here, the actual question if you were actually asking, is why (temporarily stipulating the physical record as you present it, for the sake of argument) the Antarctic proxy temperature record did not dip as far and as fast as the global (both Arctic and Antarctic) methane concentrations during that brief interval highlighted above.

Do you have any actual thoughts on the matter, do you plan to actually consider the many and various possibilities (CO2 feedback in albedo, effects of meltwater releases in the Arctic, precipitation and ocean current changes, an "inertial" effect from accumulated heat energy in non-atmospheric reservoirs, etc etc etc) or are you intending to follow your normal practice of attempting to confuse, deflect, and prevent answers - thereby attaching an allegedly (by you) "unanswered" question to a matter you want to cast doubt on, furthering an essentially political agenda?

Is this going to come back, the way the lag between temp boosts and CO[SUB]2[/SUB] boosts came back here a couple posts ago?

 

No Ilive in Brazil and drive my "flex fuel" car on 100% alcohol BECUASE IT IS CHEAPER than gasoline. Furthermore it gets NO Subsidy. It is produced by many dozens of independly competing companies none of which grow cane more than a couple hundred miles from the main markets (Rio & Sao Paulo) as cane is too bulky and low value to ship more distantly. (Oil companies falsely tell it is destroying the Amazon Forest, but all is grown more than 500 miles away form it.

Actually there is effectively a "negative subsidy" on sugar cane alcohol, as the Brazilain government owns more than 50% of PetroBras. For left wing political reasons PertoBrass has been forced to sell its gasoline at less than production cost. Look ate the record of stock price of PetroBass to seen how much it has declined (more than 80%) while other major oil company other oil company stocks have risen greatly. Even with gasoline sold at a slight loss, sugar cane alcohol is cheaper per mile driven!

 

"The entire world's needs for liquid fuel can be produced with no more than 3% of the world's arable land producing sugar cane."

Sugar Cane produces about 700 gallons per acre. Average 1 crop per year.
700 gallons ethanol = about 500 gallons gasoline..
Americans consume 140 Billion Gallons of gasoline per year.
So, just to cater for US use would require 280 Million Acres of sugar cane.
The US has 408 Million acres used in crop production.
3% doesn't sound right.

Your figure of 3%. How did you work that out?

 

"Now Liu et al, and the other pubs I mention demonstatre that the Younger Dryas was warmer than assumed and the Allerød was colder than assumed. Apparantly the Greenland isotopes are not a good paleothermometer."

From the graph, this period was one of high methane, a greenhouse gas.
Why would its being warmer than previously expected constitute a problem?

The Allerod isn't shown on the graph at all.

There seems to be a disjoint between what you want to say, and the information you are using to support your ideas.
Can you post some graphs that show the problem you are talking about?

 

Oh please. Have you read the guy's links? He's getting this crap from the standard political disinformation websites, the wingnut and Exxon funded crowd, and trying to dress it up in concepts he does not understand.

 

I'd like to see the argument stated intelligibly, with the evidence to support that argument.
Could we start with that?

A graph for a more recent period showing CO2, Methane levels, and estimated temperatures would help.
The graph just shows Oxygen and Methane levels.

From Wiki:
The Younger Dryas stadial, also referred to as the Big Freeze, was a geologically brief (1,300 ± 70 years) period of cold climatic conditions and drought which occurred between approximately 12,800 and 11,500 years BP. The Younger Dryas stadial is thought to have been caused by the collapse of the North American ice sheets, although rival theories have been proposed.

So it's a relatively short period which hasn't got consensus among experts.
Possibly not the best one to use to form a theory, but let's see where it goes.