dabize
-
Posts
917 -
Joined
-
Last visited
Content Type
Profiles
Blogs
Forums
American Weather
Media Demo
Store
Gallery
Everything posted by dabize
-
Wow - I hope they keep that drill bit well cooled. I'd hate it if we had to start awarding a Heisenberg Award alongside the Darwin Award........
-
I agree completely. I think that the differences among many of us are ones of communication - essentially word choice - more than anything else. Obviously the threats from CO2 are far better defined than any posed by CH4 release, and people should say so. That said, the CH4 threat does have a "high upside" potential (even if it is from a low base) which deserves exploration, if only because it is interesting. It would be nice to be able to explore subjects like this without constantly having to parry accusations of "alarmism" from posters who want to establish their cred with the denial crowd. Such people should know that this is impossible - those guys are impervious to rational argument, and some of them are being paid to disrupt it - see my new thread on evidence for this.....
-
That's great if you can stand it....after a while it depresses me, so I skip them.
-
Phillip - I think you are wasting your time with him. I found using the Ignore button to have great utility...it improved my mood at once.
-
http://arctic-news.blogspot.com/2012/02/methane-venting-in-arctic.html This guy likes the methane idea specifically for the Kara because the warmer waters from the Atlantic don't seem to have quite made it as far east as the Kara. I agree that the return of more normal weather to the area (Svalbard has a forecast high of -11C today with -23C days for early next week) will put the matter to the test......we look at new ice formation rates and thickness.
-
The Laptev and the Lena River Delta area look pretty solidly 1870+ only. That could mean that they are a LOT more than this number, not just a bit more (as is reasonable to assume for, say, the Kara). Looks like we just don't know and that AIRS should recalibrate their sensors and/or maps........
-
Then go away
-
I hear you - its just that on this topic, it seems to me that there are just too many variables to get a good feel for where this is going. As I have made clear in my posts, I find the S&S observations quite alarming, particularly in the context of the sea ice loss trend and all the reports of thermokarsts appearing with melting permafrost. It is very easy to see how this could become a really bad thing, especially given the willingness of most people to ignore this sort of thing until they are forced to pay attention......which they have not yet been. However, it also does seem hard to tell what the Arctic overall has been doing re CH4 release, especially before 2008. That prevents one from seeing the proper context of the S&S observations. I myself just don't know enough about other methane sources (is most atmospheric methane really tropical in origin?) to be confident about the effect of Arctic methane. My position on methane is the sort that really bugs me when I hear/see it applied to AGW overall, because the larger context for that is quite clear. But with methane (especially seabed methane), it seems that we really still don't know. I for one am really looking forward to S&S's paper And the RC thread SHOULD be interesting.....................
-
Fair enough. It's fine to not get too worked up about it, if thats how it strikes you. The scorn shown by some here (not you) for being concerned about a potentially big problem with a lot of unknown variables is a good deal less fine. I tend to agree with you that a "runaway" loop fed by short term CH4 release would not be able to feed itself on causing additional CH4 release directly from the sea floor for the reason that you mention. I am a bit disturbed by the S&S-observed increase in the ESAS, since this seems to be real and reflects a short term increase for this particular site - it is unclear whether the increase is due to AGW or via coincidental attainment of a melting threshold caused by ESAS flooding 8kya. The latter seems like a bit of a coincidence, yes, but that threshold has to be reached sometime. If there is going to be runaway feedback, it is most likely to be due to thermokarst-related effects. THAT could be due to AGW, no problem.
-
It's a discussion. All too many posters here seem to be oblivious of what that term means.
-
http://www.realclimate.org/index.php/archives/2012/01/much-ado-about-methane/#more-10412 RealClimate has a thread up no on the methane story, with the OP taking vanilla...... Should be worth watching
-
My money is on the West Kara as well http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=12&fd=31&fy=1979&sm=12&sd=31&sy=2011 Still hasn't frozen. It, like the Laptev, was not glaciated during the Wurm (or for large parts of it, anyway), and is very shallow, and so should have lots of inundated permafrost. The West Kara is away from the immediate freshening influence of the Ob/Irtysh and Yenisey (as the CH4 source sites in the Laptev are away from the Lena delta, but not very far away). This helps to retard freezing a bit as well
-
Either that or it is a massive coincidence that the permafrost melting set in motion by the flooding of the ESAS 8kya has just reached paydirt at the time when humans decided to burn 200 millions of years worth of fossil fuels. Nominally, S&S are saying the latter - at least until they look over their data - but I can't believe they really mean it. They're just being conservative.
-
http://dotearth.blogs.nytimes.com/2011/12/27/leaders-of-arctic-methane-project-clarify-climate-concerns/?src=recg Looks like Shakhova and Semiletov got back to Andy Revkin and (reading between the lines) biffed him on the nose for telling people to move along, no story here. They are pointedly saying nothing to either reassure or alarm - indeed they are saying NOTHING ahead of publication, but there are a couple of interesting points of emphasis..........the deep thawing may have nothing to do with recent AGW, but is still much greater than expected according to modeling. Also - "It is no surprise to us that others monitoring global methane have not found a signal from the Siberian Arctic or increase in global emissions." Video interview with Shakhova is excellent
-
What he said.........
-
The fact that C02 numbers are also significantly up at Barrow suggests to me that 1) it imay well be real, since CH4 is oxidized to CO2 and so should go up with CH4 levels in any nearby site after a local release....also multiple erroneous points don't seem to be common on the graphs of either CH4 or CO2.
-
Uhh check a map (not Mercator, please). Barrow is closer to the ESAS than any other site.
-
Yup. The most interesting place on the ice map right now is that area south of Novaya Zemlya in the West Kara Sea. The Ob'/Irtysh system is dumping all sorts of organic matter from millions of hectares of thawing permafrost in West Siberia - like the Lena is in the Laptev. But the West Kara also has the Atlantic influx to keep it warm, and it is just starting to freeze now. If I had the time, I'd start a Hudson Bay like poll and watch thread to see when the West Kara freezes over, and (as you said) when it thaws again in the Spring.
-
For a phenomenon localized to the Arctic (we hope), you shouldn't use Arctic temperatures?
-
http://thinkprogress.org/romm/2011/12/17/391462/our-extreme-weather-arctic-changes-to-blame/?utm_medium=twitter&utm_source=twitterfeed Link to a very nice explanation of how low ice in the Arctic leads to high amplitude jet streams and potentially more and longer snowy periods at lower latitudes. Helpful for us unwashed, at least. I post it here because the comparison of the ice maps for 1980 and 2007 shows that the ESAS region is where most of the reduction in summer extent has occurred. I know that correlation is not causation (this is not a "post hoc ergo propter hoc" argument!), but an argument COULD be raised to defend the idea that either one of these events (CH4 release and sea ice loss) might credibly play a role in facilitating the other.............
-
I think that this conclusion is based on the comparison made by the investigators themselves between conditions in the Northern Laptev this year vs past years, plus inferences drawn from the failure of earlier surveys to see things of this magnitude in the ESAS (or for that matter anywhere). Not ironclad, but reasonably convincing, especially given the extreme description of hundreds of km-wide plumes in a 10,000 square km area.
-
Not at all. The process has continued for 8,000 years, and has reached a point where CH4 release is starting to increase rapidly. That increase presumably reflects continued melting from the changes started 8,000 years ago. Continuation of that melting may very well cause continued rapid increases in CH4 release rate, irrespective of AGW. So AGW may not have caused the current increased release at the ESAS, but the interaction of increased CH4 release with an anthropogenically warmed world full of CH4 deposit sites the CAN be affected by AGW (such as thermokarsts throughout northern siberia and Canada) is something to be concerned about.
-
That abstract suggests that the current releases are due to long term permafrost degradation set in motion when the ESAS was flooded 8kya, rather than current warming. Not particularly reassuring, considering the magnitude of the recent increase in CH4 release from the site. It merely suggests that upcoming large-scale releases are coming and that there is nothing we can do to stop them.
-
When was that distribution map made? It might have changed quite a bit recently. I notice that a big color change reflects a tiny concentration change. Also, the paper I was excerpting presented measurements from the West Antarctic Ice Sheet.
-
I forgot to source my Permian/Triassic assertion: http://specialpapers...99/249.abstract Quoting from the abstract: "Catastrophic methane outbursts during terminal Permian global mass extinction are indicated by organic carbon isotopic (δ13Corg) values of less than –37‰, and preferential sequestration of 13C-depleted carbon at high latitudes and on land, relative to low latitudes and deep ocean. Methane outbursts massive enough to account for observed carbon isotopic anomalies require unusually efficient release from thermal alteration of coal measures or from methane-bearing permafrost or marine methane-hydrate reservoirs due to bolide impact, volcanic eruption, submarine landslides, or global warming." It then goes on to mention that although it is unclear whether CH4 release on such a massive scale is the cause or consequence of the Permian extinctions (of 96% of all species), such high CH4 levels are certainly toxic enough to do it. "killing by hypoxia, hypercapnia, acidosis, and pulmonary edema" We haven't even explored the possibility that elevated methane might itself cause extinctions of oceanic microbiota on a scale capable of CAUSING catastrophic methane release, but that seems to be a topic reserved for the congenitally nervous on this board.