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> from superficial permafrost. Rec
Hi Dave,
Good question, don't know but see paragraph 2. As you say, the results seem clear (most intense global warming found in the Arctic - MIGWA) , though I haven't seen the Natl Geographic article you mentioned. I had a quick look again at the long article 'Global warming' in Wikipedia, where the second graphic image gives the world temperature rise 1950-2014 that empirically confirms MIGWA. Later on, it shows computer modelling predictions of the likely future effects of global warming that again project more MIGWA (19th image down -- why don't they number the Figures?). Maddeningly, it doesn't identify the causes -- doesn't say which features of the model(s) predict the Arctic emphasis. It does say that the models drawn on by the IPCC did not incorporate any estimates from permafrost melting, so it can't be that.
If you now look instead for causes in a more specific article that I'd not noticed before, 'Global warming in the Arctic', it's more informative. In a quick look, the main cause of MIGWA identified there is the ice-albedo effect (ice/snow reflects more incoming solar radiation back into space, than does either the darker seawater or land exposed by the disappearance of the surface ice/snow; the newly exposed regions heat up proportionally more than elsewhere as a result -- no ice outside the Arctic/Antarctic to melt, so no albedo change found there). It also mentions increased recent soot deposition on arctic snow as a contributing factor of the same type.
Any methane release from permafrost, apparently not yet seriously modelled, would obviously amplify these effects. As you originally emphasized, the effects could be very serious and even dominant, but are currently poorly understood.
Steve
________________________________________
From: naturens-owner@chebucto.ns.ca [naturens-owner@chebucto.ns.ca] on behalf of David & Alison Webster [dwebster@glinx.com]
Sent: Wednesday, November 18, 2015 7:40 PM
To: naturens@chebucto.ns.ca
Subject: Re: More on Methane Hydrate ; a bit tedious Re: [NatureNS] Little Ice Age; right.
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. 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
>
>
>
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