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1
Antarctica / Re: What's new in Antarctica ?
« Last post by sidd on Today at 02:30:18 AM »
Re: Kingslake paper, doi:10.1038/nature22049

In the figure 1 i included earlier, inset d) is the the Roy Bauduoin shelf. There is a new paper at cryosphere-discuss by Berger et al. doi:10.5194/tc-2017-41 about spatial variation in basal melting on this shelf.

http://www.the-cryosphere-discuss.net/tc-2017-41/

sidd
2
Antarctica / Re: What's new in Antarctica ?
« Last post by sidd on Today at 02:26:02 AM »
"And a paper showing evidence for meltwater stabilization of an ice shelf (?!) doi:10.1038/nature22048"

the link above in the quote is to the Bell paper, not the Kingslake paper.

That Bell paper is quite interesting. Hydrofracture instability is slowed greatly by efficient export of surface melt.

"The ­calculated water export ranges from 0.04 km^3 to 0.56 km^3 in each season. In just seven days, the waterfall can export the entire annual surface melt volume produced by a melt rate of 0.5 m/yr over the shear-margin catchment. Present ice-sheet models produce rapid disintegration when surface melt rates reach 1.5 m/yr. However, our results show that this amount of ­surface melt could be removed by the waterfall in 21 days (Extended Data Fig. 6). This efficient export of surface meltwater highlights the capacity of rivers to efficiently buffer ice shelves against the damaging storage of melt."

Well, that immediately raises the question, why did this not buffer Larsen before it fell apart ? I wonder if Larsen has rivers for years before it fell apart, by we were not watching it carefully enuf. Well, good news, for a change, if it is borne out.

sidd

3
Walking the walk / Re: Sourcing solar panels and batteries
« Last post by numerobis on Today at 02:05:40 AM »
Ok, lots to read when my internet improves!

Red in particular gives me hope. Though I'm twenty degrees north of you ;)
4
Consequences / Re: Conservative Scientists & its Consequences
« Last post by AbruptSLR on Today at 02:01:22 AM »
And this is what we are currently seeing in the winter...increased humidity and clouds causing dramatic warm winter anomalies due to downward longwave radiation. This has been getting worse for at least 2 decades and represents a tipping point for the Arctic. We are seeing knock off effects all across the northern hemisphere, large positive fall snow cover anomalies being one and large changes in NH atmospheric circulation, another (cyclone cannons).

The linked Scribbler article is entitled: "Hauntingly Freakish Siberian Wildfires Now Flicker to Life in April".  High Arctic Amplification is an indication of high climate sensitivity.


https://robertscribbler.com/2017/04/24/hauntingly-freakish-siberian-wildfires-now-flicker-to-life-in-april/

Extract: "This past winter has been ridiculously warm for large sections of Siberia. From the Yamal Peninsula to Lake Baikal to the thinning ice of the Arctic Ocean and back down to the Sea of Okhotsk, temperatures have ranged from 4 to nearly 7 degrees Celsius above normal throughout the entire first quarter of 2017."
5
Arctic sea ice / Re: The 2017 melting season
« Last post by Niall Dollard on Today at 01:54:22 AM »
Methinks there's circumstantial illusions created by a chrono-illogical snapshot. The shadow effect NW of the big Bergs and off the coast exaggerates the appearance of open water in the 2016 shot. Obviously due to a strong offshore DISPERSAL and polynia creation event with warm incoming air for a number of days coming in off Canada. This cherry pick of an inverse snapshot


Shadow effect NW of the bergs?? I think not.

Cherry pick? Not intended.

Around this time last year the Beaufort was going through a torrid time. I expect many year on year comparisons of the Beaufort around this time +/- two weeks will look quite similar.

I too don't intend to crack up trying to quantify it. These are just snapshots.

Jim Hunt has archived some more images during that April/May period last year here :

http://greatwhitecon.info/resources/arctic-regional-graphs/beaufort-sea-ice-graphs/

From a vertical perspective, in my opinion it looks better there now. But that is compared against an early opening last year. Of course it is difficult to gauge what the true thickness is underneath. Although Thomas' thickness charts posted earlier do suggest it is thicker at the periphery at least.

It will be interesting to see how things develop over the Beaufort in the coming weeks. 

6
The rest / Re: The Trump Presidency (was "Presidential Poll")
« Last post by AbruptSLR on Today at 01:44:57 AM »
The linked article is entitled: "Senate staff perplexed by unusual White House private briefing on North Korea".  Another sign of Trump's imbalance.

https://www.msn.com/en-us/news/politics/senate-staff-perplexed-by-unusual-white-house-private-briefing-on-north-korea/ar-BBAhGFq

Extract: "The White House announced Monday that it would host an unusual private briefing on North Korea for the entire Senate, prompting questions from lawmakers about whether the Trump administration intends to use the event as a photo op ahead of its 100-day mark.

Press secretary Sean Spicer told reporters that the lawmakers would be briefed Wednesday by several senior administration officials, including Secretary of State Rex Tillerson and Defense Secretary Jim Mattis. He emphasized that the meeting plan had been conveyed by Senate leadership and that the White House was serving “as the location.”

Yet the White House setting perplexed lawmakers who have grown accustomed to such briefings taking place in a secure location on Capitol Hill, where there is more room to handle such a large group."
7
Arctic sea ice / Re: The 2017 melting season
« Last post by pauldry600 on Today at 01:42:59 AM »
I thought sea ice would be way less by now.

I think my estimate of 3.7m minimum has a heap of catching up to do to happen. In the past 20 days apart from bering its been boring
8
Arctic sea ice / Re: The 2017 melting season
« Last post by Bob Wallace on Today at 01:29:02 AM »

I suspect a certain flightless bird with a drippy nose could crank that out.  He's already doing other charts with the PIOMAS data. 

Let me add, I think that's an excellent idea.  Moving the goalpost is hardly ever a good idea.
Who?
(who is the flightless bird. Can he do it?)

I think Bob is referring to Arctic Penguin. :)

Yes, Wipneus.    But I seem to have messed up the translation.  In Dutch it's "tipped up nose"  or "turned up nose".  Not dripping. 
9
Arctic sea ice / Re: Arctic Image of the Day
« Last post by TerryM on Today at 01:12:14 AM »
Cate
That is amazing. I was there twice in May of 2005 & it was tee shirt weather. In just over a month in Newfoundland and Labrador we saw one far off iceberg.
A friend is headed to Ferryland this summer and is hoping the bergs there are long gone, says it chills the whole area.


Great photo
Terry
10
Arctic sea ice / Re: The 2017 melting season
« Last post by oren on Today at 12:57:58 AM »
Interesting.
According to this - http://polarportal.dk/en/havisen-i-arktis/nbsp/sea-ice-extent - a lot of 5m thick ice off Ellesmere island & Greenland, but open water in channel. Strange.

I am quoting a response I've made upthread to a similar inquiry:
This opening is very unusual up that high...

...please read the "Nares Strait" thread in the Greenland section. There is an almost-constant surface flow from the Lincoln Sea southwest down the strait. When the thick ice gets stuck at the entrance it may form an "arch", as happened this year (more often an arch is created in Kane Basin at the other end of the strait). The surface flow then keeps clearing the area below the arch.
Also search the web for the "North Water Polynya".
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