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Thanks Both, Nov 18, 2015
But how otherwise does one account for most intense warming being
restricted to the the region which is north of the Arctic Circle ?
I just scanned the image into a PDF file but then remembered that Flickr
can't accept PDF. If anyone who has not seen this issue wished to see this
image contact me offline.
Yt, Dave Webster, Kentville
----- Original Message -----
From: "Stephen Shaw" <srshaw@Dal.Ca>
To: <naturens@chebucto.ns.ca>
Sent: Tuesday, November 17, 2015 11:41 PM
Subject: RE: More on Methane Hydrate ; a bit tedious Re: [NatureNS] Little
Ice Age; right.
> 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. Rec