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hange-and-methane-hydrates/</a><br& Thanks Nancy. There are 4 of these WOR (World Ocean Reports), the first of which is the one you linked. If you look in the Authors list for each, the dates are WOR1 (yours, 'published' 2010), WOR2 (2013), WOR3 (2014), and WOR4 (2015). There is a small, newer extra section in WOR3 on methane hydrates. This and WOR1 differ from Wikipedia in emphasizing marine deposits as the likely main source of future methane release, not melted Arctic permafrost. For modelling, they consider a future ocean temperature elevation of at least 3°C, rather large. The main source of these WORs seems to be academics in ocean studies at the University of Kiel, Germany plus a few others. The reports seem conceived as information sites for the public, and are not academic documents where you could follow up anything -- no references to other work are given; it would have been nice to have had further leads. A lot of the size and date estimates are still iffy, but a conclusion at the end of section 3 of WOR3 is that there's now "a broad consensus" that major releases of methane from hydrates will not take place in this century or even in the next few centuries. Hard to know if this is a dependable conclusion. They say again (2014) that the research is still in its infancy. Steve ________________________________________ From: naturens-owner@chebucto.ns.ca [naturens-owner@chebucto.ns.ca] on behalf of N Robinson [nrobbyn@gmail.com] Sent: Tuesday, November 17, 2015 6:02 PM To: naturens@chebucto.ns.ca Subject: Re: More on Methane Hydrate ; a bit tedious Re: [NatureNS] Little Ice Age; right. Hi everyone, I found a good website with a very clear description of the potential benefits and hazards of the methane hydrate: http://worldoceanreview.com/en/wor-1/ocean-chemistry/climate-change-and-methane-hydrates/ What is being done about the risks? The last paragraph reads: "International scientific consortia are now being established involving researchers from various disciplines – chemists, biologists, geologists, geophysicists, meteorologists – which are intensively addressing this problem. No one can yet say with certainty how the methane release in the Arctic will develop with global warming, either in the ocean or on the land. This research is still in its infancy." [Textende] I could not find the year this report was published. Nancy On Mon, Nov 16, 2015 at 7:52 PM, David & Alison Webster <dwebster@glinx.com<mailto:dwebster@glinx.com>> wrote: Hi Steve & All, Nov 16, 2015 Thanks for pointing me to this. I followed a link to 'Clathrate gun hypothesis' which includes an interesting phase diagram for Methane Hydrate and Methane gas at various temperatures and pressures. The abscissa is strange in that evenly spaced ticks variously represent increments of from1 to 6 back to 1 and then up to 3 degrees; an accordion abscissa. But the significant message is clear; at sufficiently low pressures Methane gas will be released from Methane Hydrate at temperatures as low as 0oC. Kilopascals are no longer part of my vocabulary but starting with the definition that 1 cm of water is equivalent to 98.06 Pascals and rounding up; ten (10) Metres of water will be approximately equivalent to 1000 Kilopascals. And because density of water is a maximum at 4oC (not sure how salinity would affect this) one would expect bottom sediments to usually be 4o or warmer. And from the graph, Methane at 4o C would be released at depths less than about 40 metres. A map in the NG issue shows temperature change between 1960 and 2014 as colors ranging from green (cooler) through yellow, orange, and red to black; black representing the greatest increase in temperature (unnumbered pages 18 & 19). All of the bright red (>10oC increase) and black (~15oC increase) areas are north of the Arctic Circle. The black areas look like plumes of warmth extending west from the shallows north of Svalbard and Novaya Zemlya. It appears to me that the situation north of the Arctic Circle is a smoking Clathrate Gun. I wonder how Methane/altitude profiles in the fall compare with those in Temperate or Tropical areas. Yt, Dave Webster, Kentville ----- Original Message ----- From: "Stephen Shaw" <srshaw@Dal.Ca> To: <naturens@chebucto.ns.ca<mailto:naturens@chebucto.ns.ca>> Sent: Monday, November 16, 2015 12:53 PM Subject: RE: [NatureNS] Little Ice Age; right. Dave: Good reminder -- there's a bit of info at the end of the Wikipedia article on 'methane clathrates' (hydrates) that is worth a look. Two researchers in Sept 2013 in a 'Nature' offshoot reinforced Hansen's earlier warning, saying that the most likely cause of further strengthening of global warming is large scale future thawing of the Arctic permafrost. The total amount in the sea is large but estimates range widely, while estimates of land-based methane hydrates are also large, of comparable value to the lower estimates of the marine deposits. Presumably these land deposits are mostly too thinly distributed to be extracted commercially before they eventually will escape during permafrost thawing, so no hope there. The article mentions an earlier land-based successful drilling exercise to release gas, but that was into a concentrated deposit in deeper rock in the MacKenzie River delta, not from superficial permafrost. Recent info cited indicates that widespread release of marine derived methane is occurring around certain continental margins. As you say, Earth may be on the way to being severely disrupted in the not too distant future. Steve ________________________________________ From: naturens-owner@chebucto.ns.ca<mailto:naturens-owner@chebucto.ns.ca> [naturens-owner@chebucto.ns.ca<mailto:naturens-owner@chebucto.ns.ca>] on behalf of David & Alison Webster [dwebster@glinx.com<mailto:dwebster@glinx.com>] Sent: Sunday, November 15, 2015 9:00 PM To: NatureNS@chebucto.ns.ca<mailto:NatureNS@chebucto.ns.ca> Subject: [NatureNS] Little Ice Age; right. Dear all, Nov 15, 2015 I just ran across an item on Facebook (tried to copy link but got a page full) which featured activities of John Coleman, a global warming denier, who claims that the sea is not rising, that we are entering a Little Ice Age etc, etc. Total hogwash but I expect many will swallow this sugar-coated poison pill. I may be repeating myself but the Nov issue of National Geographic is entirely about climate change. Greenland is facing a near future in which traditional native culture will not be able to exist; communities are isolated and unable to hunt except during periods of firm ice and this will soon be transient or absent. But I find it unsettling that I have seen no mention or Methane hydrate in the last 5-10 years because, logically, it feeds the main feedback loop which powers unusual surges in warming. If this source of Methane is not used before it is released in significant amounts then I think we are toast. Are all researchers or all of the research funds chasing the carbon puck and ignoring Methane hydrate ? Or is the news too dire to leak to the press ? Or have I just not tripped across recent Methane Hydrate articles ? Yt, Dave Webster Kentville ----- No virus found in this message. Checked by AVG - www.avg.com<http://www.avg.com> Version: 2016.0.7227 / Virus Database: 4460/11010 - Release Date: 11/16/15
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