Frame on methane GWP

Here’s good news for all those who despair at the defects and sheer incompetence (it seems) in the calculation of the Global Warming Potential of methane: it’s about to get a high-level airing. I emailed Professor David Frame a few days ago. Prof Frame is Director of the NZ Climate Change Research Institute at the Victoria University of Wellington, taking over from Martin Manning in October last year. He’s given us a prompt and encouraging response. – h/t Barry Brill

30/06/2012 12:21 pm

Dear Professor Frame,

Your opinion piece in the Dominion of 22 June makes good reading, thank you. I was especially struck by Tom Schelling’s remark describing the EU’s emissions targets as indicating its insincerity.

But I write concerning your comment following the post. There’s been much discussion at the Climate Conversation Group about the calculation of GWP for methane, what it should be and what might be done to make it more reasonable. Set too high, it is a considerable impost on NZ farming, which as you know is among the world’s most efficient. You say:

Shorter-lived gases (such as methane) are not obviously as important for the overall properties of climate change as is commonly thought, and the way we count them – or rather the way the folks who came up with Kyoto ended up counting them – masks this by giving them high emphasis. [Unwarrantedly high emphasis in my view, but that would be another article, which is a bit more technical to write.]

Now, Dave, this is like the aroma of frying bacon to a hungry man. The idea that you might consider writing an analysis of methane’s GWP and the faults in its present calculation, as has been discussed at length here (see the Atmosphere open thread for a start) and elsewhere, is most agreeable. Perhaps restricting an article to methane and ignoring other minor gases would make it easier to compose yet strike a strong blow for our economy?

Would you, I wonder, give it earnest consideration? Could you, I implore you, have it ready for publication as soon as possible? Such an article from such a respected scholar in such a prominent position would do a great service, not just to truth and not just to our farmers, but to us all.

Warm regards,

Richard Treadgold

1/07/2012 12:32 pm
Hi Richard,

Thanks for your email. I am working on the metrics issue on several fronts at the moment – I’m writing a couple of papers (with colleagues from the UK) which I hope will appear in good journals; I’ve also talked to quite a few officials and decision makers here in NZ about it; and I’m preparing an article for public consumption on the issue, too. I haven’t been back in NZ very long, so I’m still kind of feeling my way a bit, but I’m optimistic I can make some fairly clear arguments to the effect that GWP is a very odd metric to use if your aim is to use a metric that acts as a proxy for climate damages and, therefore, the choice of a value as high as 23 for the cost of methane vs CO2 would seem hard to justify.

Dave Frame

11 Thoughts on “Frame on methane GWP

  1. Andy on July 4, 2012 at 10:15 pm said:

    This could get interesting.

    • Mike Jowsey on July 5, 2012 at 10:02 am said:

      Mmmmm! Bacon….

    • You’re easily distracted, Homer – er, Mike.

    • Andy on July 5, 2012 at 10:59 am said:

      I am glad that this is finally getting the attention that it deserves. A few of us looked into this (Jim McK in particular) and found the calculations somewhat wanting.

      This figure of GWP=23 seems to get bandied around like it is a fundamental constant of the universe – like the speed of light or Boltzmann’s constant, yet when pushed, no one knows what it means or how it was derived.

  2. Richard C (NZ) on July 5, 2012 at 11:31 am said:

    Stumbled on this while going through some Circumpolar Vortex material (NH heat waves being topical at the moment):-

    Rapid descent of mesospheric air into the stratospheric polar vortex

    Wind fields from a numerical simulation are used to give a detailed Lagrangian picture of air flow in the middle atmosphere of the southern hemisphere in winter and early spring 1991. Trajectories for many thousands of air particles exhibit rapid descent of mesospheric air into the stratospheric polar vortex, revealing its organizing and structure‐preserving properties. Results are used to account for measurements of low methane concentrations in the vortex made by the HALOE instrument on board the Upper Atmosphere Research Satellite.

    Behind paywall so I don’t know how the low concentration of methane was accounted for.

    Discovered linked at the WUWT Polar Vortex Reference Page, article also reads:-

    “The walls of the polar vortex act as the boundaries for the extraordinary changes in chemical concentrations. Now the polar vortex can be considered a sealed chemical reactor bowl, containing a water vapor hole, a nitrogen oxide hole and an ozone hole, all occurring simultaneously (Labitzke and Kunze 2005)” Stratosphere troposphere interactions: an introduction [linked]

    Also re NH heat waves:-

    Current Global Weather Patterns Normal Despite Government and Media Distortions

    by Dr. Tim Ball on June 28, 2012

    The dome of cold air over polar regions is expanding as the world has cooled since 1998. Rossby Waves in the Circumpolar Vortex that circles from west to east in the middle latitudes switched from Zonal to Meridional flow creating different weather patterns in the middle and high latitudes.

    [See graphics]

    Rossby Waves migrate from west to east on a 4 to 6 week basis. However, when the Meridional Wave amplitude gets deep, with cold air pushing toward the Equator and warm air toward the Poles the system blocks. Now the weather pattern migration becomes 8 to 10 weeks and people become nervous. That is what is happening in North America now, but all we hear about is the warm weather across the eastern half of the continent, with little mention of the cold and wet conditions in the west.

    “Media distortions” would include the Trenberth/Borestein beat-up

    • Richard C (NZ) on July 5, 2012 at 11:57 am said:

      There’s stratosphere – troposphere CH4 and H2O transport, interactions and seasonal variations e.g. see this paper:-

      Seasonal variation of methane, water vapor, and nitrogen oxides near the tropopause:
      Satellite observations and model simulations

      “The seasonal comparisons shown here highlight the
      importance of the NH summer monsoon circulations for
      contributing to STE, as discussed in Dethof et al. [1999]. In
      particular, the CH4 and H2O fields in both HALOE and
      MOZART show the localized impact of the South Asian
      monsoon in the tropopause region, and the MOZART cross
      sections (Figures 5, 10, and 11) suggest direct transport of
      constituents into the lower stratosphere via monsoon circulations”

    • Jim McK on July 5, 2012 at 1:44 pm said:

      Hi Andy,

      ..”……and found the calculations somewhat wanting”

      The IPCC random number generator got stuck on 23 in about 2004.

      I am very hopeful this time, well spotted Richard.

  3. Andy on July 21, 2012 at 9:48 pm said:

    This isn’t specifically about Methane, but David Frame’s comment at Hot Topic is well worth a read.

    • Richard C (NZ) on July 22, 2012 at 11:15 am said:

      David’s decided to exit from HT because it’s at one end of a polarized issue from what I can gather and he prefers the cozy middle ground between science and policy that confers his benefits (might be a little harsh but just my impression).

      It follows then, that he would probably exit from a group (us) that addresses feedbacks, empirical observations, IPCC AR veracity, thermodynamics and spectroscopy etc.

      So who’s left for him to “communicate” with beyond his institution and govt? His like-minds at Oxford? A compliant but ignorant NZ public?

      At least he managed to raise the level of HT to-and-fro above the gutter for a while and as comments go, that would have rate as one of the more comprehensive. This was interesting:-

      As for the position that “GHG concentrations are already at the 450 ppm” This conflates short- and long-lived gases. It’s overly pessimistic to redenominate methane (for instance) forcing as though it were much more permanent (ie CO2). It gives a false picture of where we are (and, regrettably, can lead to perverse policy incentives).

      He basically dismisses GWP and I don’t think the few of us here that have had a look at GWP would disagree with him, Jim McKinlay in particular.

    • Richard C (NZ) on July 22, 2012 at 11:26 am said:

      It’s opportune at this point to look to the ‘McKinlay GWP model’ accessible in the sidebar to the right.

  4. Richard C (NZ) on August 8, 2012 at 4:33 pm said:

    Methane – humidity – ocean oscillation – temperature relationship in this paper:-

    Did the global temperature trend change at the end of the 1990s?

    Tom Quirk

    Accepted 7 May 2012 for the Asia-Pacific Journal of Atmospheric Sciences

    5 Methane

    Atmospheric methane concentrations have been directly measured systematically since 1983 (Cunnold et al, 2002) so it is not possible to see any changes before that time. There are ice core data available covering this period (MacFarling Meure et al., 2006) but atmospheric gases trapped in the ice bubbles are averaged over a number of years and detail is lost. There is a further problem with methane measurements prior to 1990. They may well be contaminated by natural gas leakage from pipelines (Quirk, 2010).

    The level of methane in the atmosphere is understood to be controlled by the interplay of natural and anthropogenic sources with an atmospheric sink of OH radicals that removes methane. The level of OH radicals is controlled by ultraviolet solar radiation, ozone and the amount of water vapour present (Bousquet et al. 2006).

    The major (95%) sink for methane is OH radicals in the troposphere. These are concentrated in the Tropics as water vapour is their source and water vapour is at a maximum concentration in the Tropics. If there is a change in humidity at about the year 2000 then there should be a change in the rate of removal of methane from the atmosphere. An increase in humidity implies an increase in OH radicals and a consequent increase in the rate of removal and a reduced rate of increase of methane. Figure 8 shows just this effect. For the period 1991 to 2009 the annual increase in methane falls from 5.8 +/- 0.4 ppb per year before 1999 to 1.3 +/- 0.4 ppb per year after 1999.

    Methane like other components of the atmosphere has a break in its time series in 1999 +/- 1 year.

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