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Laurent

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Re: What's new in Antarctica ?
« Reply #50 on: February 03, 2015, 08:43:25 PM »
Lewis Pugh to undertake 'world's most dangerous swim' in Antarctic for campaign to make Ross Sea a protected area
http://www.independent.co.uk/environment/lewis-pugh-to-undertake-worlds-most-dangerous-swim-in-antarctic-for-campaign-to-make-ross-sea-a-protected-area-10021130.html

Laurent

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Re: What's new in Antarctica ?
« Reply #51 on: February 04, 2015, 10:16:43 AM »
Subglacial Lake Vostok cracked for a second time
http://www.newscientist.com/article/dn26907-subglacial-lake-vostok-cracked-for-a-second-time.html?cmpid=RSS|NSNS|2012-GLOBAL|environment#.VNHhO2N3_z8

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Re: What's new in Antarctica ?
« Reply #52 on: February 04, 2015, 11:31:42 AM »

Jim Hunt

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Re: What's new in Antarctica ?
« Reply #53 on: February 04, 2015, 01:14:17 PM »
Anyone have a sub to N.S. to access this?

Yes - What would you like to know?
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johnm33

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Re: What's new in Antarctica ?
« Reply #54 on: February 04, 2015, 03:29:41 PM »
 JimHunt "Yes - What would you like to know?" Well breifly his veiw, I checked out the BAS site and couldn't find anything there, the press part of it seemed dysfunctional, tried a wider search and had no luck.
Sands back at Porthleven btw.
johnm

Jim Hunt

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Re: What's new in Antarctica ?
« Reply #55 on: February 07, 2015, 07:11:27 PM »
Just posted by NASA - A chip off the King Baudouin Ice Shelf:

http://earthobservatory.nasa.gov/IOTD/view.php?id=85235

Quote
While large icebergs calve regularly from fast-flowing ice shelves in West Antarctica, the coast of cooler, drier East Antarctica tends to be less active. That made it a mild surprise when a 70-square-kilometer chunk of ice broke off from the King Baudouin Ice Shelf in January 2015. The last time that part of King Baudouin calved such a large iceberg was in the 1960s.

Also visible on WorldView on February 3rd, having already moved a fair distance: http://1.usa.gov/1EOlIwN

« Last Edit: February 07, 2015, 07:42:43 PM by Jim Hunt »
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Jim Hunt

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Re: What's new in Antarctica ?
« Reply #56 on: February 07, 2015, 08:23:29 PM »
Well breifly his veiw, I checked out the BAS site and couldn't find anything there.

Sorry John. I missed this. Too busy battling the forces of darkness! How about this bit?

Quote
There is no longer an autumn lockstep between wind and ice. The most glaring clash is in the Bellingshausen Sea. There, the autumn winds have become stronger. They blow from the north, which must be shoving more ice in towards the coast, keeping it from spreading, as well as carrying warmer air from temperate regions. Indeed, the overall area of autumn sea ice here has declined, which would seem to fit with that idea. But if the stronger winds were the key factor affecting ice growth, the ice should be growing more slowly. In fact, during autumn it is growing faster than it did a few decades ago. "That destroys my earlier work," Holland says.

He now thinks that to understand these changes in sea ice, we need to focus on what's happening in the spring. In the Bellingshausen Sea, ice is now retreating earlier in the springtime, letting the ocean absorb more solar heat. That warming should delay the regrowth of ice – accounting for the decline in ice area in autumn. But when the ice does grow back, it does so quickly, because now the ocean is open to the air, it rapidly loses its heat again.

In other words, sea ice has a tendency to bounce back from big spring losses. This was first noted in Antarctica by Stammerjohn, in a 2008 study that looked at how ice is changing region by region and season by season.

or this?

Quote
Dirk Notz, however, is not convinced that Holland is right to focus on whether sea ice is melting or forming faster or more slowly than it used to. "He is looking at a change in a rate of change," he says. "I do not think it's a measure that is important."

So Notz's team thinks that the wind explanation still holds. The reason most climate models have been projecting sea ice losses, they argue in a study published in December, is that they are too coarse-grained. They miss details of Antarctic topography that deflect winds northwards and spread out sea ice, allowing more ice to form.

Returning to a still somewhat chilly SW England.

Quote
Sands back at Porthleven btw.

I'm glad to hear it!
"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

Laurent

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Re: What's new in Antarctica ?
« Reply #57 on: February 12, 2015, 10:08:29 AM »
Fishing vessel trapped in Antarctic ice; U.S. Coast Guard on rescue mission
http://www.latimes.com/nation/la-na-coast-guard-20150211-story.html

solartim27

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Re: What's new in Antarctica ?
« Reply #58 on: February 12, 2015, 09:51:40 PM »
I don't know how new this is, but I found that Polar View also has antarctic Sentinel images available, though i find the coverage lacking
http://www.polarview.aq/antarctic

There is also another site that looks like it is new from University of Alaska, Fairbanks.  I don't know how much coverage it will give to the Antarctic.
https://www.asf.alaska.edu/
FNORD

wili

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Re: What's new in Antarctica ?
« Reply #59 on: February 15, 2015, 06:16:16 PM »
Sorry if this was already covered somewhere, but it seems like kind of a big deal:

http://www.the-cryosphere-discuss.net/9/861/2015/tcd-9-861-2015.html

Newly developing rift in Larsen C Ice Shelf presents significant risk to stability


Quote
An established rift in the Larsen C Ice Shelf, formerly constrained by a suture zone containing marine ice, grew rapidly during 2014 and is likely in the near future to generate the largest calving event since the 1980s and result in a new minimum area for the ice shelf. Here we investigate the recent development of the rift, quantify the projected calving event and, using a numerical model, assess its likely impact on ice shelf stability. We find that the ice front is at risk of becoming unstable when the anticipated calving event occurs.

More, and image, here: http://www.desdemonadespair.net/2015/02/image-of-day-satellite-view-of-rift.html

ETA: Ah, I see ASLR (of course) has a couple posts on this with many good images on the neighboring thread "Discussion of Antarctic Peninsula"
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AbruptSLR

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Re: What's new in Antarctica ?
« Reply #60 on: February 17, 2015, 02:34:15 AM »
The linked article states that: "Penguins can taste only sour and salty food, scientists have discovered.  A genetic study suggests the flightless birds lost three of the five basic tastes long ago in evolution."


http://www.bbc.com/news/science-environment-31490623
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Laurent

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Re: What's new in Antarctica ?
« Reply #61 on: February 20, 2015, 02:03:34 PM »
You want a job in Antartica ?
http://www.ukaht.org/about-us/jobs

Chuck Yokota

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Re: What's new in Antarctica ?
« Reply #62 on: March 16, 2015, 06:31:03 PM »
East Antarctica Melting Could be Explained by Oceanic Gateways

http://www.utexas.edu/news/2015/03/16/east-antarctica-melting-could-be-explained-by-oceanic-gateways/

Quote
AUSTIN,Texas — Researchers at The University of Texas at Austin’s Institute for Geophysics (UTIG) in the Jackson School of Geosciences have discovered two seafloor gateways that could allow warm ocean water to reach the base of Totten Glacier, East Antarctica’s largest and most rapidly thinning glacier. The discovery, reported in the March 16 edition of the journal Nature Geoscience, probably explains the glacier’s extreme thinning and raises concerns about how it will affect sea level rise.

Totten Glacier is East Antarctica’s largest outlet of ice to the ocean and has been thinning rapidly for many years. Although deep, warm water has been observed seaward of the glacier, until now there was no evidence that it could compromise coastal ice. The result is of global importance because the ice flowing through Totten Glacier alone is sufficient to raise global sea level by at least 11 feet, equivalent to the contribution of the West Antarctic Ice Sheet if it were to completely collapse.

“We now know there are avenues for the warmest waters in East Antarctica to access the most sensitive areas of Totten Glacier,” said lead author Jamin Greenbaum, a UTIG Ph.D. candidate.

The ice loss to the ocean may soon be irreversible unless atmospheric and oceanic conditions change so that snowfall outpaces coastal melting. The potential for irreversible ice loss is due to the broadly deepening shape of Totten Glacier’s catchment, the large collection of ice and snow that flows from a deep interior basin to the coastline.

crandles

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Re: What's new in Antarctica ?
« Reply #63 on: March 27, 2015, 03:06:26 AM »
Volume loss from Antarctic ice shelves is accelerating

Quote
The floating ice shelves surrounding the Antarctic Ice Sheet restrain the grounded ice-sheet flow. Thinning of an ice shelf reduces this effect, leading to an increase in ice discharge to the ocean. Using eighteen years of continuous satellite radar altimeter observations we have computed decadal-scale changes in ice-shelf thickness around the Antarctic continent. Overall, average ice-shelf volume change accelerated from negligible loss at 25 ± 64 km3 per year for 1994-2003 to rapid loss of 310 ± 74 km3 per year for 2003-2012. West Antarctic losses increased by 70% in the last decade, and earlier volume gain by East Antarctic ice shelves ceased. In the Amundsen and Bellingshausen regions, some ice shelves have lost up to 18% of their thickness in less than two decades.

http://www.sciencemag.org/content/early/2015/03/25/science.aaa0940

http://www.bbc.co.uk/news/science-environment-31965454

DavidR

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Re: What's new in Antarctica ?
« Reply #64 on: March 27, 2015, 09:17:54 AM »
New research shows Antarctic ice shelves thinned rapidly in the last decade and much faster than scientists had thought.
This may just  be another take on the articles report by  crandles.
http://www.abc.net.au/news/2015-03-27/antarctic-ice-shelves-thinning-more-rapidly-scientists-thought/6354530
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Clare

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Re: What's new in Antarctica ?
« Reply #65 on: March 29, 2015, 07:34:57 AM »
Tim Naish -Director of the Antarctic Research Centre at Victoria University of Wellington. He will discuss the new findings this week on the decrease in volume of Antarctic ice on Radio NZ.

http://www.radionz.co.nz/national/programmes/saturday/audio/20172781/tim-naish-antarctic-ice-shelves

He always explains things v clearly, this is a summary of recent research for a general audience, the interviewer herself has been to Antarctica in past.
Pic =Travelling out to Andrill drill site on Ross Ice Shelf in 2006 with Tim

Sleepy

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Re: What's new in Antarctica ?
« Reply #66 on: March 29, 2015, 09:06:23 AM »
Thanks Clare, that was indeed a very nice interview.
No big news for a lot of people reading here, but I think it's very usable in communicating the scientific view to those who never read.
I'll add the mp3 version here.

Sigmetnow

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Re: What's new in Antarctica ?
« Reply #67 on: March 29, 2015, 07:18:11 PM »
Quote
The warmest temperature ever recorded on the continent of Antarctica may have occurred on Tuesday, March 24, 2015, when the mercury shot up to 63.5°F (17.5°C) at Argentina's Esperanza Base on the northern tip of the Antarctic Peninsula. According to weather records researcher Maximiliano Herrera, the previous hottest temperature recorded in Antarctica was 63.3°F (17.4°C) set just one day previously at Argentina's Marambio Base, on a small islet just off the coast of the Antarctic Peninsula. Prior to this week's remarkable heat wave, the hottest known temperature in Antarctica was the 62.8°F (17.1°C) recorded at Esperanza Base on April 24, 1961. (The World Meteorological Organization—WMO—has not yet certified that this week's temperatures are all-time weather records for Antarctica, though the Argentinian weather service has verified that the temperatures measured at Esperanza Base and Marambio Base were the highest ever measured at each site.) A new all-time temperature record for an entire continent is a rare event, and Weather Underground's weather historian, Christopher C. Burt, has full details in his latest post.
Dr. Jeff Masters:
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2944&cm_ven=tw-jm

Christopher C. Burt:
http://www.wunderground.com/blog/weatherhistorian/comment.html?entrynum=323#

WaPo:
http://www.washingtonpost.com/blogs/capital-weather-gang/wp/2015/03/27/antarctica-may-have-set-highest-temperature-ever-recorded-tuesday/

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Laurent

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Re: What's new in Antarctica ?
« Reply #68 on: April 01, 2015, 10:07:51 AM »

AbruptSLR

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Re: What's new in Antarctica ?
« Reply #69 on: May 06, 2015, 01:26:35 AM »
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Laurent

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Re: What's new in Antarctica ?
« Reply #70 on: May 08, 2015, 09:54:45 AM »

Laurent

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nukefix

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Re: What's new in Antarctica ?
« Reply #72 on: May 22, 2015, 03:07:59 PM »
A new campaign in Antarctica has started in Cycle 49, i.e. yesterday. AP and parts of WAIS will be covered in IW-mode (~10m pixel size) in HH-polarization.



Pmt111500

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Re: What's new in Antarctica ?
« Reply #74 on: June 04, 2015, 12:28:51 PM »
Some new things to me at least:
https://www.youtube.com/watch?t=16&v=yCunWFmvUfo

solartim27

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Re: What's new in Antarctica ?
« Reply #75 on: June 06, 2015, 09:20:51 PM »
FNORD

solartim27

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Re: What's new in Antarctica ?
« Reply #76 on: June 06, 2015, 11:46:42 PM »
Deep ice core in Antarctica used to compare to conditions in Greenland:
http://www.realclimate.org/index.php/archives/2015/04/how-long-does-it-take-antarctica/
FNORD

Clare

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Re: What's new in Antarctica ?
« Reply #77 on: June 28, 2015, 11:52:55 AM »
Good long detailed Q&A with Nancy Bertler:
"Antarctica - our big icy threat"
http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=11472481

& you can see her 'on the job' in this clip from Thin Ice:
https://vimeo.com/43012949

(sorry but I cant fathom how to embed this as a video. :-(  )

http://thiniceclimate.org/blog/details/2013/digging-a-snow-pit-in-antarctica-nancy-bertler

Clare

Jim Hunt

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Re: What's new in Antarctica ?
« Reply #78 on: July 03, 2015, 09:52:06 AM »
(sorry but I cant fathom how to embed this as a video. :-(  )

The forum software doesn't seem to understand Vimeo. Is there a YouTube version of the same video?
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AbruptSLR

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Re: What's new in Antarctica ?
« Reply #80 on: July 15, 2015, 05:27:35 PM »
The linked article discusses fifty-million-year-old worm sperm cells found frozen in Antarctic ice:

http://www.huffingtonpost.com/entry/worlds-oldest-sperm-discovered-in-antarctica_55a65d9ce4b0c5f0322bcb6f

Extract: "Fifty-million-year-old sperm cells from a worm have been found in Antarctica, National Geographic reports. The fossilized sperm, which was preserved in the walls of an egg case, is the “oldest fossil animal sperm yet known,” according to a paper published Wednesday in the journal Biology Letters by researchers at the Swedish Museum of Natural History in Stockholm."
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Pmt111500

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Re: What's new in Antarctica ?
« Reply #81 on: September 29, 2015, 05:09:27 AM »
University of Exeter scientists have included the effect of water buoyancy differences of the Ocean water in their model, thus getting their model to behave more like the measurements state. Not surprising at all, the expansion of cold ocean areas around Antarctica let more CO2 to get in there thus a large portion of the glacial-interglacial variations on CO2 levels and temperatures maybe included in some paleoclimate models better than previously.

"During an ice age, the glacial conditions on Antarctica mean that the water near to the continent is colder and so less buoyant. The upwelling of warmer water - during which CO2 is lost to the atmosphere - occurs further away from Antarctica enabling carbon dioxide to be drawn down into the ocean, and also producing a larger volume of deep cold water in the Southern Ocean in which carbon can be stored."

The article is likely behind the pay-wall, thus PhysOrg refers:
Read more at:
http://phys.org/news/2015-09-ocean-circulation-rethink-climate-conundrum.html

Lennart van der Linde

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Re: What's new in Antarctica ?
« Reply #82 on: October 06, 2015, 09:14:41 AM »
Zwally et al 2015 on snowfall in the interior of Antarctica offsetting ice loss at the edges, for now:
http://www.nature.com/news/gains-in-antarctic-ice-might-offset-losses-1.18486?WT.mc_id=TWT_NatureNews

If true, this would imply more ice loss from GIS or small glaciers, and/or more thermal expansion, and/or less overall SLR, for now.

AbruptSLR

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Re: What's new in Antarctica ?
« Reply #83 on: October 06, 2015, 05:29:42 PM »
Zwally et al 2015 on snowfall in the interior of Antarctica offsetting ice loss at the edges, for now:
http://www.nature.com/news/gains-in-antarctic-ice-might-offset-losses-1.18486?WT.mc_id=TWT_NatureNews

If true, this would imply more ice loss from GIS or small glaciers, and/or more thermal expansion, and/or less overall SLR, for now.

The following extract is from the author & indicates that his findings do not mean that we do not need to worry about AIS contribution to SLR, only that there is still uncertainty about timing & rate of contribution:

Extract: "The findings do not mean that Antarctica is not in trouble, Zwally notes. “I know some of the climate deniers will jump on this, and say this means we don’t have to worry as much as some people have been making out,” he says. “It should not take away from the concern about climate warming.” As global temperatures rise, Antarctica is expected to contribute more to sea-level rise, though when exactly that effect will kick in, and to what extent, remains unclear."
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A-Team

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Re: What's new in Antarctica ?
« Reply #84 on: October 07, 2015, 01:28:55 PM »
The Zwally paper has been accepted but the stodgy Journal of Glaciology does not provide an online copy and there's no telling when it will appear, firewalled, in an issue. Reviewer comments are kept secret permanently.

A copy could like be obtained by emailing Zwally at his NASA profile page. His older papers are available for download at https://www.researchgate.net/profile/H_Zwally2/publications

Mass gains of the Antarctic ice sheet exceed losses
H. Jay Zwally, Jun Li, John W. Robbins, Jack L. Saba, Donghui Yi, Anita C. Brenner
accepted Journal of Glaciology #15J071

Antarctica mass balance has gone back and forth for years by ±75 Gt, Grace gravity vs laser altimetry. The latter has serious issues with firn modelling. Zwally attributes the difference to how GRACE researchers account for changes in the height of the bedrock (isostatic rebound). We have not yet heard from the other side.
Quote
Glacial ice forms as snow compresses under its own weight. In this case, the gain in ice mass in parts of Antarctica has not come from snowfall in the modern era, but from heavier snows that fell about 10,000 years ago, says Zwally. That snow became ice and started to flow slowly towards the sea — but so slowly that the ice began to thicken.
In my view, the mass gain approach makes sense until it doesn't. The issue today is really warm ocean waters lapping at the underside of vast ice shelves. As these come to destabilize grounded ice up-glacier, any slight excess of snowfall over ablation will fall through the floor quantitatively speaking.

The Swally paper is also saying Greenland mass balance has been figured quite wrong, ie it is contributing more to sea level rise than thought. I'm recalling 1/3 which would have to go to 2/3 since thermal expansion is not likely to be misfigured. Yet Greenland, being so much smaller and experimentally accessible than Antarctica, is better studied by these very same two techniques. So how do we get to 100% error in Greenland measurements?

Lennart van der Linde

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Re: What's new in Antarctica ?
« Reply #85 on: October 14, 2015, 11:17:37 PM »
New study by Golledge et al on Antarctic ice loss projections for the coming centuries/millennia:
http://nature.com/articles/doi:10.1038/nature15706

Wipneus

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Re: What's new in Antarctica ?
« Reply #86 on: October 16, 2015, 07:22:11 AM »
NSIDC announced Antarctic sea ice maximum on October the 6th.

http://nsidc.org/arcticseaicenews/2015/10/antarctic-sea-ice-at-its-2015-maximum/

2015 was not record high:

Quote
It is likely that this slowing of late-winter ice growth is related in part to the build-up of the El Niño conditions.
(...)
Patterns of sea ice concentration around Antarctica (the deviation from average ice concentration) for El Niño years show a similar pattern, with more ice near the Peninsula.



crandles

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Re: What's new in Antarctica ?
« Reply #87 on: October 16, 2015, 03:30:04 PM »
NSIDC
Quote
Only one year, 2002, has had a later maximum (October 12).

However area maximum reached on day 248 is equal 8th earliest area maximum.

Early area maximum and late extent maximum would, I guess, be another sign of the 'slowing of late-winter ice growth'  that is likely due to El Nino.

(The years with earlier area maximums: 2010 2004 2002 1994 1992 have at least some El Nino nearby even if 1989 and 1985 do not.)

Timothy Astin

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Re: What's new in Antarctica ?
« Reply #88 on: October 16, 2015, 03:30:58 PM »
Hansen and Sato's manuscript paper

http://www.columbia.edu/~jeh1/mailings/2015/20151012_IceMeltPredictions.pdf

(earlier version dated 21st September was the subject of a brief forum thread https://forum.arctic-sea-ice.net/index.php/topic,1406.0.html)

They also comment on the EL Nino impact on 2015 winter extent of Antarctic sea ice.  The map in Wpneus' post shows the positive anomalies in ice being particularly in the western hemisphere, especially west of the Antactic peninsula, which is where Hansen and Sato predict the maximum outflow of land-ice meltwater, a pattern they predict to intensify.

Timothy Astin

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Re: What's new in Antarctica ?
« Reply #89 on: October 16, 2015, 03:59:01 PM »
New study by Golledge et al on Antarctic ice loss projections for the coming centuries/millennia:
http://nature.com/articles/doi:10.1038/nature15706

Anyone got access to the full article care to comment on this paper?  From the abstract and publically available figures, it appears "conservative" in its predictions compared to other recent papers, presumably because of the viscous ice model used.  But I'd need to read the text to make a judgement.

Even if the paper's predictions are at the lower end of best current knowledge (as I think they probably are), its predictions for sea level change have all sorts of implications.

Just one example local to me. The regional council are keen to build some 7000 new houses on the Trent coastal floodplain, and planning officers advised by the UK Environment Agency believe that it will remain above water in 85 years time.

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Re: What's new in Antarctica ?
« Reply #90 on: October 16, 2015, 08:39:26 PM »
The linked reference finds that wind induced snow mass loss from East Antarctica is dominated by sublimation with the mass transported downwind as water vapor.  This new finding indicates that the AIS contribution to SLR will be greater than previously recognized:

Indrani Das, Ted A. Scambos, Lora S. Koenig, Michiel R. van den Broeke, Jan T. M. Lenaerts (2015), "Extreme wind-ice interaction over Recovery Ice Stream, East Antarctica", Geophysical Research Letters, by DOI: 10.1002/2015GL065544

http://onlinelibrary.wiley.com/doi/10.1002/2015GL065544/abstract

Abstract: "Surface snow accumulation over East Antarctica is an important climate indicator but a difficult parameter to constrain. Surface mass ablation dominates over persistent wind-scour zones as near-surface katabatic winds accelerate over locally steeper ice surface topography, and sublimate and redistribute snow. Here we quantify ablation rates and downwind redeposition of snow over wind-scour zones in the upper Recovery Ice Stream catchment. Airborne radio echo-soundings show a gradual ablation of ~16–18 m of firn, corresponding to ~200 years of accumulation, over these zones and ablation rates of ~54 kg m−2 a−1 (54 mm water equivalent a−1). We conclude that mass loss is dominated by sublimation and mass is transported downwind as water vapor, because snow redeposition downslope of the wind-scour zones constitutes only a small fraction (<10%) of the cumulative mass loss."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: What's new in Antarctica ?
« Reply #91 on: October 18, 2015, 06:48:23 PM »
The following article provides an overview while siding a little on the side of least drama (as most of the published reports that it cites are):

http://www.smh.com.au/environment/antarctica-trouble-at-the-edge-of-the-world-20151013-gk7w4m.html
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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Laurent

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Re: What's new in Antarctica ?
« Reply #92 on: October 19, 2015, 05:12:02 PM »
Warming Oceans May Threaten Krill, a Cornerstone of the Antarctic Ecosystem
http://www.nytimes.com/2015/10/20/science/australia-antarctica-krill-climate-change-ocean.html?partner=rss&emc=rss
Quote
“We thought the krill might be more robust,” said Dr. Kawaguchi, a biologist who works for the Australian government’s Antarctic Division. “We were not expecting such a clear result.”

Laurent

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Re: What's new in Antarctica ?
« Reply #93 on: November 26, 2015, 11:49:06 AM »
Big data reveals glorious animation of Antarctic bottom water
http://nci.org.au/2015/11/24/big-data-reveals-glorious-animation-of-antarctic-bottom-water/


A-Team

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Re: What's new in Antarctica ?
« Reply #94 on: November 26, 2015, 04:57:53 PM »
That's a fabulous animation from the technical standpoint, worth watching over and over. To phong-render this many frames at this HD resolution might take months on a personal computer.

It also very good at making its talking points which, being inherently 3D, are very difficult to convey with a cartoon or explain in verbiage.

The main quibble would be, how could the underlying experimental data possibly be reliable over a vast area that is rarely and sparsely sampled and not visible to satellite? The response: it is entirely the output of a model, presumably constrained to the little concrete data that exists. This doesn't matter too much if what it is conveying is a representative simulation of actual conditions.

[Update: just noticed a quote "so much data was used, that it took seven hours to process just one second of the animation." http://nci.org.au/2015/11/24/big-data-reveals-glorious-animation-of-antarctic-bottom-water/]
« Last Edit: November 27, 2015, 02:47:29 PM by A-Team »

oren

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Re: What's new in Antarctica ?
« Reply #95 on: November 27, 2015, 02:16:17 PM »
Beautiful animation

AbruptSLR

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Re: What's new in Antarctica ?
« Reply #96 on: December 03, 2015, 12:12:08 AM »
The linked article discusses the first commercial air flight to Antarctica as well as possible future commercial flights:

http://www.popularmechanics.com/flight/news/a18380/first-commercial/

Extract: "On November 26, a commercial Boeing 747 passenger jet successfully landed on a blue-ice field in Antarctica for the first time. The landing was organized by Antarctic Logistics & Expeditions (ALE), and the airliner was piloted by Loftleidir Icelandic as "part of a larger investigation into the use of such aircraft for ALE's Antarctic operations."
The Boeing 747 was landed on Union Glacier, near ALE's primary camp. ALE transports between 400 and 500 people to Antarctica each year, primarily scientists traveling to the frigid continent to conduct research projects. Passengers have traditionally traveled in combination cargo/passenger planes that are well equipped to handle ice landings, such as the Lockheed L 100 Hercules and Ilyushin Il-76. "The Boeing 757-200 ER, fitted with 62 business class seats, will enhance passenger comfort yet maintain the safety of ALE's activities and aircraft resources," says ALE.
Successfully landing passenger airliners on Antarctica also opens the door for tourism and recreational trips. Traditionally, travelers to Antarctica who are not part of an official scientific expedition have arrived in boats from Chile or South Africa."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: What's new in Antarctica ?
« Reply #97 on: December 03, 2015, 12:41:41 AM »
 The linked article discusses how the Halley VI British Antarctic Station is being relocated this Austral Summer to avoid being part of a major calving event for the Brunt Ice Shelf (see that attached image):

https://www.newscientist.com/article/dn28600-massive-crevasse-in-the-ice-forces-early-move-for-antarctic-base/

Extract: "Life on a floating ice shelf is precarious enough, but when a massive crack is heading your way, you know you’re in trouble. This nightmare scenario is what’s forcing the UK’s newest research station in Antarctica to relocate.

Halley VI opened in 2013 to much fanfare due to its space-age design. It’s built as eight modules on skisso that it can be towed to a new location if the ice conditions change.



The crack is extending in the direction of Halley VI at a rate of 1.7 km a year, and is 8 km away from the base. “We don’t know what will happen,” says Gudmundsson. “It might stop growing, but we can’t exclude the possibility of a big calving event.”
The main concern is that Chasm 1 will grow so much that it makes it impossible to relocate the base in the future. That’s why a move is now underway."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Laurent

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Re: What's new in Antarctica ?
« Reply #98 on: December 04, 2015, 08:08:58 PM »
Rising atmospheric carbon dioxide actually cools part of Antarctica
http://news.sciencemag.org/environment/2015/12/rising-atmospheric-carbon-dioxide-actually-cools-part-antarctica

Quote
In a world where most regions are warming because of increasing concentrations of atmospheric carbon dioxide (CO2), central Antarctica has been cooling slightly in recent years. Greenhouse gases such as CO2 typically trap heat radiated back toward space from the planet’s surface, but large swaths of the East Antarctic Ice Sheet (the broad pink mass on the right side of the image) are, on average, actually colder than the upper layers of the atmosphere for much of the year—the only place on Earth where that’s true. When the team looked at the overall balance between the radiation upward from the surface of the ice sheet and the radiation both upward and downward from the upper levels of the atmosphere across all infrared wavelengths over the course of a year, they found that in central Antarctica the surface and lower atmosphere, against expectation, actually lose more energy to space if the air contains greenhouse gases, the researchers report online and in a forthcoming Geophysical Research Letters. And adding more CO2 to the atmosphere in the short-term triggered even more energy loss from the surface and lower atmosphere there, the team’s climate simulations suggest. The topsy-turvy temperature trend stems, in part, from the region’s high elevation; much of the surface of the ice sheet smothering East Antarctica lies above an elevation of 3000 meters, so it is much colder than it would be at lower altitudes. Moreover, that region often experiences what meteorologists call a temperature inversion, where temperatures in the lowest levels of the atmosphere are cooler than those higher up. For the lower-altitude fringes of the icy continent, and for the rest of the world (even Siberia and Greenland), the greenhouse effect still works as expected.

AbruptSLR

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Re: What's new in Antarctica ?
« Reply #99 on: December 04, 2015, 08:16:28 PM »
Rising atmospheric carbon dioxide actually cools part of Antarctica

What they don't note is that this effect will help sustain strong circumpolar wind speeds as the ozone hole heals itself, thus maintaining the advection of unusually high volumes of warm CDW to the grounding lines of key Antarctic marine glaciers (like PIG).
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson