By the way, if 7% of total RF didn't sound that important in the last post, please remember that that means an RF that is almost 16% as big as CO2's RF since industrialization, and I was suggesting that we might conceivably have a means to tackle it safely and quite cheaply, with existing technologies - so that would be quite significant.
cheers, Nathan On Thu, Jul 28, 2011 at 8:35 PM, nathan currier <[email protected]>wrote: > Hi, Andrew - > > It would be great if someone like Mike MacCracken could comment on some of > the chemistry in your posting - in that it seems to me confusing, and, I > suspect, somewhat confused. Could you, Andrew, show the reactions that > you're thinking of, so I could understand better? You say that - "If the > coating acts on NOx and or the OH radical, it may even be counter > productive!" and also say that "OH recycles NOx." Also you write: "NOx > production uses free raw materials and is well mixed through the > atmosphere." > My understanding goes against pretty much all of this, if I am > understanding you correctly. > > NOx certainly gets involved in reactions that lead to increased RF. But > generally NOx is considered climate neutral, I believe, because if you take > a NOx-centric view, you see it taking part in various reactions that have > both positive and negative indirect forcings, and that roughly cancel each > other out. > > If you look at, say, the NOx-methane interactions, where NOx laden air > produces more O3 in CH4 oxidation, then that added forcing is generally > counted for as part of CH4's indirect forcing, not counted for as a > "indirect forcing" for NOx. That makes more sense, I suppose, in that the > methane is fundamental to creating the greenhouse effect anyhow, is one of > the most primary biomolecules on the planet, etc. > > NOx, I believe, always demands considerable energy to create (what did you > mean by OH recycles it?), since it demands the splitting of the N2 triple > bond, so the NOx in our air is almost all anthropogenic and comes from > internal combustion engines and such. There's very little of it in > unpolluted air, except from lightning and other high energy things. OH is > the primary oxidant of the atmosphere, and, though it can fluctuate a good > deal, the total budget is assumed to be surprisingly stable, given all the > human assaults on the atmosphere. > > Thus, if you look at more recent RF pie charts (Shindell at GISS has done > lots of work on indirect RFs), NOx is not there at all, but VOCs and CO > obviously are, and are quite important - indeed, they have added twice the > RF of N2O, which, unlike NOx, IS a fundamental part of non-anthropogenic > chemistry and of the planet's GH effect. > > So, the way I see it, then, if you can catalyze more OH production directly > from the sun's energy, either from singlet O or from splitting an O3 (not by > creating new O3!), that's a very good thing. But, on the other hand, you > want to get rid of NOx, not increase it. NOx will increase the CH4 indirect > forcing, and while it will create some OH - and OH gets "reincarnated" in > the process of the methane oxidation chain of reactions - that's your BAD > OH, in that it's leading to the creation of more O3, I think. > > In terms of TiO2 being practical or not, obviously if white roofing is > practical, then the photocatalytic surface is, too. They both use TiO2. And > white roofing is the most "practical" of all geoengineering, in that no one > is opposed to it. The surface would be much cheaper than the paint. Even > solar energy might use TiO2 as well. Of course, if ALL of that happened, > there'd be a big crunch on TiO2 and the need to search for new sources. > > The most confused part of your post seemed to me: "Tio2 works well on > poorly mixed pollutants with a high contact area, none of which applies to > methane." But that's the whole point: the NOx discussion is essentially a > red herring in terms of climate impacts, but these > "poorly mixed pollutants" - the VOCS and CO - are almost 7% of +RF since > industrialization - and their RF is really all methane-related: It's an > indirect forcing coming from the OH budget deficit they cause, in turn > slowing the methane sink. > > But, you see, the TiO2 makes new OH from singlet O + H2O, or O3, and it > acts on those "poorly mixed pollutants" like VOCs and CO effectively, as you > agree - which are in copious quantities all around human surfaces. This > should then cut down on that 7% of RF by reducing a major indirect forcing, > and thus speeding up methane's oxidation. > > Cheers, > > Nathan > > > > > > > On Thu, Jul 28, 2011 at 3:22 PM, Andrew Lockley > <[email protected]>wrote: > >> This proposed method of methane remediation is similar to the existing >> sink, as although OH radical production isn't strictly catalytic, it does >> recycle NOx. Whether the chemistry works or not is something I can't comment >> on. >> >> However, I don't think that TiO2 is likely to be practical. Although it >> is leveraged (as it uses the suns energy), it is limited in the contact >> surface area, potential area of application and the availability and >> possibly the cost of raw materials. In contrast NOx production uses free raw >> materials and is well mixed through the atmosphere. Tio2 works well on >> poorly mixed pollutants with a high contact area, none of which applies to >> methane. >> >> I'm also not sure of the proposed TiO2 chemistry. If the coating acts on >> NOx and or the OH radical, it may even be counter productive! >> >> I'd be prepared to be proved wrong on all of the above :-) >> >> A >> On 28 Jul 2011 18:50, "Nathan Currier" <[email protected]> wrote: >> > Hi Andrew, Sam, Oliver - >> > >> > I heartily agree, & think that this is potentially one of the >> > "sleepers" of the geoengineering world - >> > it is also unique in that it is neither CDR nor SRM & would probably >> > be quite safe & thus easily enacted. >> > >> > I would doubt that you're going after it the right way, though, Sam, >> > in that the kinds of things >> > you have been thinking about always demand passing air - which is way >> > too >> > energy-intensive. And Oliver, clearly one doesn't want to be >> > intentionally making >> > any new GHGs while trying to fix the GHG problem, unless it's making >> > something pretty damn >> > destructive of GHGs later on!..... >> > >> > Andrew, I'm not sure what you meant by "leveraging existing >> > processes", >> > but I had an idea in this general line several years ago, and actually >> > first learned of this >> > group when I saw Mike mentioning to Ken something about it...... >> > >> > In a sense, it is like using the band gap energy used in solar cells, >> > but the energy makes >> > hydroxyl instead.....of course, that's already a well developed idea, >> > and it all started >> > in Japan - it's sometimes called the "Fujishima effect" after Akira >> > Fujishima who started it. >> > It's been used in various forms of environmental remediation for quite >> > some time now. >> > >> > It's all about exploiting the unique photocatalytic properties of >> > TiO2. At this point there has now been lots >> > of research in Japan (and much of it not translated, I've been told), >> > and there are even commercial products >> > called "environmental nano-coatings" and so on. There's a leading TiO2 >> > expert at UVA (John Yates) who I approached about all this, >> > who told me once of visiting Fujishima, and being taken to a place in >> > Tokyo where a whole block of large city buildings >> > have been covered in a TiO2 coating, and studies have shown the NOx, >> > O3, & CO, VOCs and other reactive species >> > are all greatly reduced around there from the surrounding air - with >> > huge % changes, 30% and more. >> > >> > So, my simple idea had been this: if one thinks of the atmospheric OH >> > sink as a drain in which more reactive species selectively >> > go down more easily, raising OH anywhere and letting it act on VOCs >> > etc, should, globally considered, accelerate >> > the methane sink thus lowering the CH4 forcing (and that's behind the >> > "indirect GWP" concept of such species). Since >> > methane is a LLGHG, Sam, it's a waste to spend energy pushing air >> > around - methane is already everywhere. >> > >> > Therefore, an entirely passive approach could be to add a photo- >> > catalytic coating on top of white surfacing. It's a highly >> > synergistic concept, since the TiO2's unique hydrophobic/hydrophilic >> > qualities also make it an albedo booster (keeping white things >> > whiter), by being a self-cleanser of surfaces (TiO2 is used to keep >> > windows cleaner, for ex.) It would be MUCH cheaper than the white >> > paint used for the surfacing, by at least a few orders of magnitude. >> > My guess would be this approach could greatly boost the climate impact >> > of white surfacing projects, and I haven't seen studies exploring this >> > at all yet, although grad students at UVA told me it probably has >> > already been studied in Japan, and I never had good enough data to >> > even make my own rough calculations of what it might yield. >> > >> > Now, then, I mentioned that it's kind of like solar energy, in a >> > sense. Do you know of Graetzel, who started the Graetzel cell? >> > That's a solar cell that's TiO2 based (and could be the "Next Big >> > Thing" for the world, if it turns out well.....i.e., the solar slurry >> > idea). >> > I had once come across a very early paper of his, and think it could >> > lead to something in this area you are all looking at: >> > he was studying the capacity to degrade methane in ambient conditions, >> > & so was studying TiO2 with co-catalysts. He wrote a paper >> > on a molybdenum doped TiO2 that seemed to have a good action on >> > methane at ambient temperature. So this would be more like pulling the >> > methane right down the drain, rather than waiting for the lowered VOCs >> > etc to help the methane go down it. It would demand a LOT of work to >> > both explore various co-catalysts and see what's the best for directly >> > attacking methane, and then to determine which route would be better >> > to pursue - such a targeted catalyst, or a simpler "OH maker" that >> > targets nothing at all, but helps "open the drain." >> > >> > As far as that last goes, another thing: John Yates (the one at UVA), >> > while he right away told me that he "doesn't invent things," and thus >> > had no interest in getting involved directly in my pursuit, did >> > mention a curious thing to me, in a presentation he arranged for me by >> > some of his grad students. The unique properties of TiO2 come from >> > defects in the crystal lattice structure of the molecule. He's the >> > world's leading expert of this, a theoretical chemist who has spent >> > his life perfecting his own construction (a specially dedicated kind >> > of SEM, I think) to look deep inside the TiO2 molecule. One thing he >> > said to me stuck in my mind: it might not be hard, he said, to use >> > nano tech to expand the defect of the O atom, and thus get more OH >> > made through its band gap activation. So, this could make a more >> > productive molecule - either for making solar energy, or, I suppose, >> > for taking junk out of the air and lowering its RF. >> > >> > cheers, >> > >> > Nathan >> > >> > ps - re arctic methane - since this is mild approach, I doubt it would >> > be a big part of dealing with any emergency there, but if it were, it >> > could involve adding such a coating on top of the kind of recycled >> > plastic faux ice-floe idea that I've mentioned before in this >> > group.... >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > I got another UVA chemistry faculty (Lehmann) who has developed >> > perhaps the most sensitive way of reading methane, with dual lasers, >> > interested in helping me run some simple experiments. >> > >> > >> > >> > >> > >> > >> > On Jul 26, 7:32 am, Andrew Lockley <[email protected]> wrote: >> >> Creating OH radical is best done by leveraging existing processes. >> >> The radical is too short-lived to be effectively distributed when >> >> produced industrially, and energy costs are also too high. >> >> >> >> The NOx recycling reaction series was chosen by L Zhou et al in their >> >> recent paper, as (in dry air) NOx is persistent and recycles. >> >> >> >> For the paper, seehttp:// >> www.atm.helsinki.fi/FAAR/reportseries/rs-109/abstracts/Luxi%20... >> >> >> >> Biological processes are able to indirectly create NOx by nitrogen >> >> fixation using symbiotic bacteria in root nodules. The plants can >> >> then be burned to liberate NOx into the atmosphere. The Lupin is one >> >> potential candidate, but other N2 fixers such as clover may also work. >> >> This could additionally perhaps be used as a source of biochar. The >> >> slight complexity is that NOx rains out in wet air, but the plants >> >> need to be grown in wet soil. Haul costs are likely to be a >> >> significant issue, therefore. >> >> >> >> One slightly 'far out' approach is to press ahead with the attempts to >> >> make non-legumes capable of fixing N2 through GM. This would >> >> revolutionize global agriculture, as well as giving a feedstock for >> >> geoengineering - as the N2 fixation process is the chemical >> >> underpinning of protein creation in crops. This isn't fanciful, and >> >> lots of work is already being done. >> >> >> >> An alternative technique with a much more limited scope of application >> >> is the addition of Br2 to create Br radical. This would need to be >> >> done in clean, damp air overlying the oceans. There is an existing >> >> 'hole' in the global OH shield east of Papua New Guinea, where this >> >> technique could be applied.http://eprints.ifm-geomar.de/10069/ It is >> >> one of the authors of this paper who suggested the Br technique to me. >> >> >> >> The downsides of creating NOx, as Zhou et al note, is that the both >> >> NOx itself, and the trop O3, are both toxic and also GHGs in their own >> >> right. It's not a pleasant solution to have to be considering. >> >> >> >> Readers should note the Kyoto controls on NOx, which have a beneficial >> >> effect by potentially reducing forcing, but a negative indirect effect >> >> by reducing OH radical production, which will become more significant >> >> in a low OH, high CH4 atmos. However, it should also be noted that >> >> locally high NOx concentrations are associated with different >> >> chemistry which does not lead to the production of OH and the >> >> consequential breakdown of methane. Therefore, industrial OH >> >> controls, particularly in smoggy cities, are generally beneficial, >> >> whereas in rural areas those same controls may have a positive RF >> >> outcome. >> >> >> >> This is a very interesting field, and one that more assistance and >> >> input is welcomed in. >> >> >> >> A >> >> >> >> On 26 July 2011 10:54, Sam Carana <[email protected]> wrote: >> >> >> >> >> >> >> >> > Oliver Tickell wrote: >> >> >> Another approach would be to enhance HO hydroxyl in the atmosphere - >> the >> >> >> main destroyer of methane. I have no idea how to set about doing >> this. It >> >> >> could be helpful to reduce emissions that utilise existing hydroxyl, >> such as >> >> >> miscellaneous hydrocarbons. But the chemistry is complex and it is >> hard to >> >> >> strictly follow through any intervention to its end results! >> >> >> >> > There are a number of methods that seek to reduce methane whilst >> still >> >> > in the water (microbes, bubbles, covering the water surface with >> white >> >> > plastic to capture the methane, etc). >> >> >> >> > One problem is that, in many places (including in ESAS), waters are >> >> > shallow and there's little time for microbes to do their work, >> >> > especially when hydrates suddenly start releasing huge amounts of >> >> > methane. >> >> >> >> > Therefore, it's crucial to also look at hydroxyl and I advocate two >> >> > types of feebates to help reduce emissions that compete for hydroxyl: >> >> > 1. Energy feebates (seeking to reduce emissions from power plants and >> >> > help electrify transport); and >> >> > 2. Fees on livestock products to fund biochar, which will reduce >> >> > methane, while encouraging pyrolysis and thus also reduce BC, VOC >> and >> >> > the like. >> >> > >> http://knol.google.com/k/sam-carana/the-way-back-to-280-ppm/7y50rvz99... >> >> >> >> > As to enhancing hydroxyl in the arctic, here are some suggestions: >> >> >> >> > - Tri-Air Developments has developed a technology that combines UV >> >> > light with extremely low levels of ozone and mixes it with volatile >> >> > hydrocarbons, to produce hydroxyls. This technology is used in >> Cirrus3 >> >> > devices that emit hydroxyls in rooms of less than 25m3 up to rooms in >> >> > excess of 500m3 (image below). Perhaps such technology could be used >> >> > at large scale in the Arctic to combat the methane menace. >> >> >> >> > - Another method may be to use UV light for photolysis of hydrogen >> peroxide. >> >> >> >> > - Using UV light to break down methane in the Arctic could possibly >> be >> >> > achieved by model airplanes, equipped with LiPo batteries and with >> >> > solar thin film mounted both on top of and underneath the wings. >> >> > Numerous such planes could navigate the Arctic by autopilot in >> summer, >> >> > when there are high concentrations of hydrogen peroxide and when the >> >> > sun shines 24-hours a day. Flying figure-8 patterns with the wings >> >> > under an angle could optimize capture of sunlight, keeping the planes >> >> > in the air, while using surplus energy to power UV lights. At the end >> >> > of summer, the planes could return home for a check-up and possible >> >> > upgrade of the technology, to be launched again early summer the next >> >> > year. >> >> >> >> > >> http://knol.google.com/k/the-threat-of-methane-release-from-permafros... >> >> >> >> > Cheers! >> >> > Sam Carana >> >> >> >> > On Tue, Jul 26, 2011 at 1:44 PM, John Nissen <[email protected]> >> wrote: >> >> >> >> >> Thanks Oliver. >> >> >> >> >> I'm posting your comments to the geoengineering group with the >> questions you >> >> >> raise: >> >> >> >> >> 1. Could the CDM be used to fund, or help fund, our pilot project >> to trial >> >> >> various techniques for tackling the Arctic methane problem? Could >> it >> >> >> subsequently fund deployment of selected techniques? >> >> >> >> >> 2. Is there any way to enhance HO hydroxyl in the atmosphere? >> >> >> >> >> Cheers, >> >> >> >> >> John >> >> >> >> >> --- >> >> >> >> >> On 25/07/2011 17:52, Oliver Tickell wrote: >> >> >> >> >> Certainly it makes sense to do something about large, concentrated >> methane >> >> >> emissions where it is realistic to capture the gas and burn it off, >> or use >> >> >> it for heat / power. >> >> >> >> >> Does the CDM currently provide credits for methane projects of this >> type? I >> >> >> believe it does for methane from pig farms etc so there is no >> obvious reason >> >> >> why it should not. >> >> >> >> >> Another approach would be to enhance HO hydroxyl in the atmosphere - >> the >> >> >> main destroyer of methane. I have no idea how to set about doing >> this. It >> >> >> could be helpful to reduce emissions that utilise existing hydroxyl, >> such as >> >> >> miscellaneous hydrocarbons. But the chemistry is complex and it is >> hard to >> >> >> strictly follow through any intervention to its end results! >> >> >> >> >> Oliver. >> >> >> >> >> -- >> >> >> Oliver Tickell >> >> >> >> >> On 25/07/2011 15:09, Veli Albert Kallio wrote: >> >> >> >> >> I think definitely that we can prevent on-shore methane explosions, >> and >> >> >> saturated methane laden water pockets that are approaching >> nucleating point. >> >> >> >> >> There are 3 types of methane leaking: >> >> >> >> >> 1) generic leaking of methane from melting permafrost over large >> areas that >> >> >> provide widespread methane haze >> >> >> 2) spot type ongoing methane leaking from permaforst or onshore gas >> fields >> >> >> that are losing their subterranean gas compression due to ruptures. >> >> >> 3) explosive methane eruptions (methane clatrates, Lake Cheko's >> conical >> >> >> basin gas field failure in Tunguska 1908 as river fell into gas >> field and >> >> >> drove methane out). >> >> >> >> >> No. 1 you cannot control. No. 2 depends on how big and focused the >> leaking >> >> >> is, there are vast bubbling spots, in Azerbaijan there are flaming >> mountains >> >> >> where gas comes out of rocks. These you can control. No. 3 can be >> controlled >> >> >> by method of Professor Michel Halbwachs. Often methane can be >> spotted as a >> >> >> very focused leak on sea floor which might be possible to cap. So, I >> think >> >> >> the idea is valid in certain cases, in other cases it may not be >> workable. >> >> >> >> >> ________________________________ >> >> >> Date: Mon, 25 Jul 2011 11:28:12 +0100 >> >> >> From: [email protected] >> >> >> Subject: Re: Arctic methane workshop, London, 15-16th October >> CONFIRMED >> >> >> To: [email protected] >> >> >> >> >> John, I think you are on a hiding to nothing trying to trap or >> destroy the >> >> >> methane. >> >> >> >> >> The reason is simple - the emissions are spread over such a vast >> area of >> >> >> many millions of sq.km. Even to trap and destroy the methane >> emissions from >> >> >> 1sq.km would be a fantastically difficult and expensive task. >> >> >> >> >> So you can simplify things by just ruling this one out at the start! >> >> >> >> >> Oliver. >> >> >> >> >> -- >> >> >> Oliver Tickell >> >> >> >> >> On 22/07/2011 18:29, John Nissen wrote: >> >> >> >> >> Dear all, >> >> >> >> >> In case you were not aware, the workshop, which was to have been >> 3-4th >> >> >> September, is now going to be on 15-16th October. Here is the >> background >> >> >> and purpose of the workshop... >> >> >> >> >> A group of scientists and engineers (including myself) is deeply >> concerned >> >> >> about the potential of methane from thawing permafrost in the Arctic >> to >> >> >> cause irreversible, catastrophic and unsurvivable global warming. >> Major >> >> >> factors are the unexpectedly rapid retreat of sea ice [1] and the >> >> >> unexpectedly large quantities of carbon which might be emitted as >> methane >> >> >> [2]. In June 2010 we wrote an open letter to Obama's scientific >> adviser, Dr >> >> >> John Holdren, suggesting action was urgently needed to address the >> methane >> >> >> issue [3]. Some sea ice experts, including Professor Peter Wadhams >> in our >> >> >> group, now reckon the Arctic Ocean will very likely become >> seasonably ice >> >> >> free this decade if there is no action to cool the Arctic. >> >> >> >> >> Recently Peter Wadhams has drawn my attention to work of Natalia >> Shakhova >> >> >> with Igor Semiletov on East Siberian Arctic Shelf (ESAS) - >> particularly >> >> >> concerning the present large emissions of methane and the >> possibility of >> >> >> release of much larger quantities "at any time". So we have been >> wondering >> >> >> whether anything can be done quickly to reduce this methane >> threat. We >> >> >> have been discussing possible action, and plan >> >> >> >> ... >> >> >> >> read more ยป >> > >> > -- >> > You received this message because you are subscribed to the Google >> Groups "geoengineering" group. >> > To post to this group, send email to [email protected]. >> > To unsubscribe from this group, send email to >> [email protected]. >> > For more options, visit this group at >> http://groups.google.com/group/geoengineering?hl=en. >> > >> > > > > -- > Nathan Currier > 108 Ellwood Street, #43 > New York, NY 10040 > 401-954-3402 > www.nathankindcurrier.com > > > > -- Nathan Currier 108 Ellwood Street, #43 New York, NY 10040 401-954-3402 www.nathankindcurrier.com -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
