I wouldn't be too worried about methane explosions in the open atmosphere. The lower explosive limit of methane in air is 4.4 - 5% by volume. Microbial oxidation will consume the excess methane well before it can accumulate to that level.
A few numbers please: How much timber biomass is presently available in the arctic? How much is outside of protected preserves? How much additional biomass do you expect to grow in the arctic in 10 years, 20, 50, 100? Does the analysis assume the warming you are trying to avoid? = Stuart = -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Sam Carana Sent: Sunday, February 08, 2009 3:47 PM To: geoengineering Subject: [geo] Focus of Geo-engineering? Hi everyone, I had some discussion with Albert Kallio on our focus and I like to share some of it and hear what everyone thinks. ================= Arctic Timber Drowning ================= I coined the phrase Arctic Timber Drowning for Albert's idea, because I want to avoid using the term "dumping", which sounds too negative. ======================= Genetically-modified Vegetation ======================= As I said to Albert, the effectiveness of vegetation growth could be enhanced by planting specific types of trees that grow rapidly. Seedlings could be planted while felling timber. Genetically-modified trees could grow even faster. Having brought up the bad-publicity-due-to-terminology issue, should we avoid the issue of genetically modifying vegetation? Alternatively, should we encourage discussion and present genetically-modified vegetation as a separate geo-engineering proposal? Should we select and modify vegetation for rapid growth, such as bamboo? Should we encourage crop that can grow using very little water, while at other places using vegetation that can grow rapidly with large amounts of water? Should we look at plants that can prevent erosion, grow in salty water, etc. What is the scope of applying bio-technology to engineer all kinds of vegetation with the specific aim of mitigating global warming? What would be the impact on food, etc? Importantly, should we come up with guidelines on genetically-modified vegetation, after having assessed the risks? ==================== What should be Our Focus? ==================== That brings us to the question of our role and focus as a group. Earlier, Andrew emphasized the point that it will be difficult to get legal approval and there will be political opposition against geoengineering, specifically methods that "dump" anything into oceans. I agree with Andrew that this will have to be taken into account when assessing the possible success of methods. However, to what extent should and could we assess the success of geoengineering proposals? I believe that everyone will agree that we should be aware of the political issues associated with geoengineering, but shouldn't our primary focus here be on the more technical and engineering side of things, i.e. coming up with estimates for effectiveness, side-effects, how things will work out biologically, etc? Rather than having a political or socio-economic debate about what constituted the "best" geo-engineering proposal, I agree with Stuart that we should try and examine scenarios by coming up with figures on volumes, timescales, etc. At the same time, I believe we have a duty to discuss hazards and inform the public about the dangers of specific developments. In particular, I would like to see the risk assessed of a "Sudden Methane Explosion". ==================== Sudden Methane Explosion ==================== I prefer to use the phrase "Sudden Methane Explosion" over phrases like "Clathrate Gun Theory". I want to avoid using words like clathrate and theory, which sound too 'scientific' and too distant for people who might avoid further reading when encountering a "difficult" word. This touches on our responsibility to publicly speak out on such an issue without cloaking hazards in scientific terms. I therefore propose to speak about the Sudden Methane Explosion hazard. In particular regarding Arctic Timber Drowning in lakes and rivers, we have to look at the risk of emissions due to underwater rotting, specifically methane emissions. There's the doomsday scenario which I like to call the "Sudden Methane Explosion" hazard. Methane oxidation now takes place by tropospheric chemical reaction with hydroxyl radicals (OH), producing CH3 and water. As more methane enters the atmosphere (due to livestock, burning of peat deposits and melting permafrost), the amount of tropospheric hydroxyl decreases, so methane will remain in the atmosphere ever longer, an accumulation that could accelerate into a huge local built-up of methane. Lightning could then ignite the methane, resulting in a 'Sudden Methane Explosion' that could rage like wildfire over the Arctic. Theoretically, this could reach incredible temperatures, consuming entire lakes, complete with water and the timber at the bottom of these lakes, everything in its path further fueling the fire. ============================= Let's examine many ideas, and hazards ============================= I suggest that we examine such methane hazards further. Does anyone have further data on research into such a hazard? As Albert says, Arctic timber drowning could use timber from newly developing forests in the Arctic, so it could be done without affecting existing forests or agriculture. It could also be done independently from pyrolysis of vegetation and other carbon-containing bio material (such as animal manure) elsewhere. Nonetheless, as said, we should compare methods such as pyrolysis and Arctic timber drowning with alternatives such as deep ocean burial. Let's try and put more figures on the various scenarios. Cheers! Sam Carana --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
