2011-06-04 08:12:21First draft of new Nature paper on Canadian Arctic Archipelago
MarkR
Mark Richardson
m.t.richardson2@gmail...
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Trouble Brewing in the North

HBO’s new mega-series A Game of Thrones (‘The Sopranos in Middle Earth’ according to the marketing people) has a stupendous wall of ice.

http://www.fantasysfblog.com/pics/game_of_thrones_the_wall.jpg

Figure 1 – The Wall, copyright HBO

In the story, people piled up 5 billion tons of ice across a 300 mile line to keep their lands safe from the dangers to the North.

Keeping our northern ice safe also keeps much of our land safe; but we’re not doing a particularly good job. The trillion plus ton loss of ice in Greenland since 2000 has been well covered, but its baby brothers in the Canadian Arctic Archipelago (CAA) are still quite hefty and we haven’t heard much about them specifically. A recent Nature article by Gardner et al (LINK) provides a very concise update.

http://www.skepticalscience.com/images/CAAmap.jpg

Figure 2 – Ellesmere Island and Baffin Island, the areas measured by Gardner et al 2011

The scientists wanted to determine an up to date ice mass balance re: the total change in amount of ice in tons. Positive means more snow than melt and growing caps & glaciers whilst negative means the opposite.

Being good scientists, the team used several independent methods. For Ellesmere Island there are measurements of snowfall and glacier loss, allowing a ‘surface mass balance plus discharge’ (SMB+D) model to estimate the mass balance, although lack of ground data for Baffin meant they couldn’t use this in the south.

Satellites measured both; ICEsat used a laser radar (LIDAR) to measure ice thickness which can be converted into mass, whilst GRACE is a pair of satellites that measure the gravitational ‘tug’ of Earth on each other and can directly measure changes in mass on Earth.

The measurements agree; these Canadian ice caps have lost about 400 billion tons of ice since 2003, an average of 12 of those stupendously big ice walls I showed at the beginning melting away every year.

http://www.skepticalscience.com/images/CAAbalance.jpg

The loss sped up drastically as the decade went on but the authors are clear that ‘the duration of the study is too short to establish a long term trend’ and that in Alaska, the melt rate has slowed slightly in the same time period.

The CAA experienced 4 of its 5 warmest summers since 1960 during the study and the team used the model to calculate that most loss was from melting rather than changes in snowfall.  They found that each degree Celsius of warming meant another 64+-14 billion tons of ice melted during the year and whilst the ice caps overall contributed 0.17 +- 0.02 mm/year to sea level rise, the last 3 years averaged 50% higher than this and with more warming to come

 

 

 

Still need to put in the conclusion - another 2 paragraphs and it's a rough first draft. Been in a stupendous rush recently and I'm going to France in 5 hours and we haven't packed yet so I'll polish it off once I get there!

2011-06-05 07:00:48
dana1981
Dana Nuccitelli
dana1981@yahoo...
69.230.102.37

Looks good so far.  There's a few minor editorial things I noticed like missing commas, but it's easier for me to go in and fix those before the post is published.  Have fun in France!

2011-06-05 07:20:39
Rob Painting
Rob
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Yup, looks good. Nice to get some kind of visual context for what those massive numbers mean (even if it is CGI!).

2011-06-06 17:55:38
logicman

logicman_alf@yahoo.co...
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As many of you will know, I am something of a history buff - my most recent article* was about the history of Henry Ford's views on history.  :-) 

I have been studying a map which shows areas of the Arctic which had been charted as of 1906 - including the fictitious Keenan Land.  The map is of relevance to the new paper.

The 1906 Justus Perthes Arctic map shows an inaccurate and incomplete chart of the Canadian Archipelago with an intriguing reference to the 'Nordamerikan kaltespol' - North American pole of cold - centred approximately on the coast which was formerly home to the Ellesmere ice shelf.  The cartographer's location of a 'pole of cold' ties in with what we know of the loss of the ice shelves and the now frequent opening of the various North West passages.

The loss of the massive Ellesmere ice shelf - a loss now nearly complete - suggests to me that a century of warming in that region of the Arctic must have been greater than in any other Arctic or subarctic region.  Accordingly, I find the conclusions by Gardner et al about mass loss to be unsurprising.  I expect the loss to accelerate.

 

The Justus Perthes 1906 map is available from Wikimedia:

http://commons.wikimedia.org/wiki/File:Arctic_Ocean.jpg

 

[*] - http://www.science20.com/chatter_box/henry_ford_quote_history_bunk-79505

2011-06-08 21:46:02
MarkR
Mark Richardson
m.t.richardson2@gmail...
93.21.78.149

Article here!

Please comment and correct, as soon as it's done up I'm happy to have it released and I also want to apologise for my lack of writing (and the haste in which I threw this together) - I've been exceptionally busy. Only in my first year of PhD and already drowned in work!

 

 

logicman: does that necessarily mean that the warming has been greatest there? It could be a case that these areas were just closer to freezing during the melt periods than others for example. Also, Gardner et al note that the precipitation rates are very low so if Greenland and the CAA received a similar percentage increase in precip from warming, then Greenland would 'benefit' a lot more from it and the CAA would look a lot more sensitive.

Although they also note that precip changes have contributed to the loss.

2011-06-09 01:27:49Reinforcing reference?
John Hartz
John Hartz
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99.95.221.238

Perhaps it would be approprtiate to weave in a reference to the paper described in the following news release:

Scientists from Queen’s and Carleton universities head a national multidisciplinary research team that has uncovered startling new evidence of the destructive impact of global climate change on North America’s largest Arctic delta.

“One of the most ominous threats of global warming today is from rising sea levels, which can cause marine waters to inundate the land,” says the team’s co-leader, Queen’s graduate student Joshua Thienpont. “The threat is especially acute in polar regions, where shrinking sea ice increases the risk of storm surges.”

By studying growth rings from coastal shrubs and lake sediments in the Mackenzie Delta region of the Northwest Territories – the scene of a widespread and ecologically destructive storm surge in 1999 – the researchers have discovered that the impact of these salt-water surges is unprecedented in the 1,000-year history of the lake.

The above are the first three paragraphs of a news release (May 16) posted on the Queen's University webiste.

http://www.queensu.ca/news/articles/striking-ecological-impact-canada-s-arctic-coastline-linked-global-climate-change

 

2011-06-09 01:39:06
dana1981
Dana Nuccitelli
dana1981@yahoo...
64.129.227.4

Looks good Mark.  I went in and made a few minor editorial changes.  One question on the last sentence:

"and it seems that we can add these Canadian islands to the list of Alaska, Greenland, and Arctic sea ice where trouble is already brewing in the North."

it sounds like you're referring to sea ice in Alaska and Greenland as well.  Perhaps revise to read "to the list of other northern ice (Alaskan [glaciers?], Greenland ice sheets, and Artic sea ice) where trouble is brewing", or something like that.

2011-06-09 07:43:13
Rob Painting
Rob
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118.93.8.61

- "used the model to calculate that most loss was from melting "  = calculate that greater loss

- "A slight decline in Alaskan melt rate means that outside Greenland and Antarctica" = a slight increase

Looks good to me.


2011-06-09 08:27:57
Andy S

skucea@telus...
66.183.188.172

GRACE is a pair of satellites that measure the gravitational tug of Earth on each other and can 'weigh' things below them.

I think this could be worded better, eg. GRACE is a pair of satellites that fly above the Earth about 200km apart at a height of 500 km. Small variations in the Earths gravity cause the distance between the satellites to vary a little, which allows us to measure the gravity field very precisely.

 Or maybe more simply than that. Grace is a pair of satellites that allow us to measure the Earth's gravity field very accurately by measuring the slightly varying distance between them.

Richard Alley likened the Grace project to two unattached roller-coaster cars that get further apart as one of them starts rolling downhill and vice-versa. The satelllites are called "Tom" and "Jerry" naturally.

A slight decline in Alaskan melt rate means that outside Greenland and Antarctica, these two islands are now the biggest regions of land ice melt on the planet.

Suggest: Because the rate of meltng in Alaskan glaciers has decreased recently[?ref], Baffin and Ellesmere Islands are now the biggest contributors to land-ice melt after Greenland and Antarctica.

an up to date ice mass balance

Suggest: an up-to-date ice-mass balance  (too many nouns in a row)

 

Otherwise, great!

2011-06-09 11:37:55
logicman

logicman_alf@yahoo.co...
86.144.0.115

Thumb!

Mark: in response to your question, a 'pole of cold' marks an area of persistent lowest Arctic winter temperatures.  For a pole of cold to vanish it must warm faster than surrounding areas.  In the CA this can happen - and in my view has happened - from warm water intrusion into the relatively shallow passages between the islands.

2011-06-28 07:00:06
MarkR
Mark Richardson
m.t.richardson2@gmail...
134.225.187.197

"- "A slight decline in Alaskan melt rate means that outside Greenland and Antarctica" = a slight increase"

 

 

Rob - Gardner et al comment that there has been a sight decrease. From 88 to 70 bn tons/year average. They reference it in the paper, but it's an update to a paper I've found... minus the update. Made the suggested language changes and now ready to publish I think.

2011-06-28 14:25:16
dana1981
Dana Nuccitelli
dana1981@yahoo...
71.137.108.93

Cool, will add it to the schedule.

2011-06-28 18:53:31
MarkR
Mark Richardson
m.t.richardson2@gmail...
192.171.166.144

Hold on, does that mean you'll release it, or should I? :P

2011-06-29 06:55:11
dana1981
Dana Nuccitelli
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64.129.227.4

I will.  I've been doing most of the publishing these days.  It's on the schedule for later this week (Saturday, UK time).