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Or maybe 'iconic', as in: 'his iconic blog'.
PIOMAS July 2017
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: Last month we finally received some good news from PIOMAS, and the good news continues this month. Wi...
Neven, you're in the Dutch newspaper Volkskrant:
http://www.volkskrant.nl/wetenschap/minder-zeeijs-op-noordpool-dan-ooit~a4310488/
PIOMAS June 2016
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: As of May 31st the 2016 trend line is lowest on the graph. A sea ice volume decrease of 3037 km3 duri...
Colorado Bob, thanks for the Kevin Anderson talk! Good to hear this update on his views.
An exceptional exception
Winter is supposed to be a time when things quiet down in the Arctic, animals hibernate in complete darkness, and all that can be seen from satellites is this great, icy mass getting bigger and bigger. That's how it goes most of the time, despite the spectacular summer sea ice losses of the pas...
Alley, Box and Rignot commenting via the Washington Post:
http://www.washingtonpost.com/news/energy-environment/wp/2015/08/19/one-of-the-worlds-fastest-melting-glaciers-may-have-just-lost-its-biggest-chunk-of-ice-ever/
Jakobshavn record retreat
What a coincidence. Yesterday I wrote in a comment: There's a fantastic segment on the Arctic Sea Ice Forum for discussing Greenland and its glaciers, with people presenting all kinds of analysis and satellite images. Really top quality stuff. Well, the folks there (forum member Espen Olsen to...
Look who's tweeting:
https://twitter.com/erignot/status/633572684710866948
Jakobshavn record retreat
What a coincidence. Yesterday I wrote in a comment: There's a fantastic segment on the Arctic Sea Ice Forum for discussing Greenland and its glaciers, with people presenting all kinds of analysis and satellite images. Really top quality stuff. Well, the folks there (forum member Espen Olsen to...
Nice guest blog in the Guardian, Neven:
http://www.theguardian.com/environment/climate-consensus-97-per-cent/2015/jul/29/2015-arctic-melting-season-wont-break-records-but-could-wipe-the-recovery?CMP=twt_environment*gdneco
[Thanks, Lennart. I was waiting for this to get published. Still can't log in on my own blog, which is why I answer like this; N.]
2015 SIPN Sea Ice Outlook: July report
The second Sea Ice Outlook of this year has been published. The SIO is organized by the Sea Ice Prediction Network (as part of the Arctic research program 'Study of Environmental Arctic Change', or SEARCH), and is a compilation of projections for the September 2015 Arctic sea ice extent, based ...
o-oh...
ASI 2015 update 4: massive heat
During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily Cryosphere Today sea ice area (SIA) and IJIS sea ice extent (SIE) numbers, which I compare to data from the 2005-2014 period (NSIDC has...
Can you tell what kind of alien?
ASI 2015 update 4: massive heat
During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily Cryosphere Today sea ice area (SIA) and IJIS sea ice extent (SIE) numbers, which I compare to data from the 2005-2014 period (NSIDC has...
Colorado Bob, thanks for the link to the Alley-lecture. I reposted it on the ASIF.
ASI 2015 update 1: early start in Beaufort
During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily Cryosphere Today sea ice area (SIA) and IJIS sea ice extent (SIE) numbers, which I compare to data from the 2005-2014 period (NSIDC has...
"157 million people living at an average of 10m abovw sea level"
If I remember correctly worldwide about 600 million to one billion live at 10m or less above sea level.
Bill McKibben nails it
This simply has to be shared, as Bill McKibben expresses my thoughts exactly. This sentence just about says it all: "It’s as if the tobacco companies were applying for permission to put cigarette machines in cancer wards. And the White House gave Shell the license." I haven't seen such a good m...
"It’s as if the tobacco companies were applying for permission to put cigarette machines in cancer wards. And the White House gave Shell the license."
There's an important difference with smoking though: smoking can be done without endangering everyone else's health; burning oil and emitting CO2 can't be done without endangering the health of everyone else's home planet.
Bill McKibben nails it
This simply has to be shared, as Bill McKibben expresses my thoughts exactly. This sentence just about says it all: "It’s as if the tobacco companies were applying for permission to put cigarette machines in cancer wards. And the White House gave Shell the license." I haven't seen such a good m...
Nice report, Neven, thanks. On the links, this one to Torge Martin is not right:
http://meetingorganizer.copernicus.org/EGU2015/EGU2015-2018.pdf
On the regional model by Maslowski and his group: did they say anything (new) on their 2016 +/- 3yrs ice-free projection/extrapolation?
EGU2015, my impressions
Tempus fugit. It feels like an eternity, but it was only last week that I went to Vienna to visit the EGU 2015 General Assembly. This is the overview I wrote last week of all the oral and poster sessions I planned to attend. Here's a summary of my impressions and what I've seen, heard and learn...
Susan,
This may be the best place at the forum to start:
http://forum.arctic-sea-ice.net/index.php/topic,393.0.html
But it may take some time to find the info you're looking for, if it's there.
The Ns are calling the maximum
Here's a quick update on everything related to our good friend Max. In the past couple of days organisations like the NSIDC, NASA and NOAA have announced the annual event of the Arctic sea ice pack reaching its largest size at the end of the freezing season. This has been picked up widely by the...
It may be unlikely the max will be passed, but we've been surprised before.
Neven, you write:
"Quite a few storms have been funnelled into the Arctic via this route this winter, but this is a really big one, potentially bombing out at 950 hPa. It's difficult to tell what its influence will be on extent numbers at this final stage of the melting season."
This "melting season" should be "freezing season", right?
Mad max?
Okay, I'm not calling the max - short for maximum extent of the sea ice pack that marks the end of the freezing season - as I've sworn not to do that anymore since 2012, when I called the max twice, only to see the trend line bounce up higher and later. But this year something really interestin...
"What kind of chicken did we have in the oven?" That indeed seems to be the question.
How frozen was it? How warm will the oven stay for how long, this year? Will the Arctic suprise us yet again?
ASI 2014 update 4: high times
During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily Cryosphere Today sea ice area (SIA) and IJIS sea ice extent (SIE) numbers, which I compare to data from the 2005-2013 period (NSIDC has...
The NASA-post being picked-up:
http://www.livescience.com/46264-greenland-glacier-loses-ice-photo.html
Jakobshavn calves a(nother) big one
Greenland glacier guardian Espen Olsen informed us a couple of days ago on the Forum that Jakobshavn Isbræ - Greenland's fastest glacier draining 6.5 % of the Greenland ice sheet - has had another big bite taken out of its southern branch recently. Espen made this animation to show the differenc...
So far this year it seems to have been on average about 7 degrees C warmer than normal in the Arctic:
http://ocean.dmi.dk/arctic/meant80n.uk.php
Ice extent is at about the record minimum for this time of the year. And spring is in the air. At least here in Holland it is, where so far this winter we've had no full day below zero degrees C, for the first time ever. Average Holland temperature this winter (extended fall) has been second highest so far (only 2007 had a higher average).
Let's see how fast the Northern hemisphere snow cover will melt this spring.
Decreasing Arctic albedo boosts global warming
A new paper in PNAS, called Observational determination of albedo caused by vanishing sea ice, reminds me of scientific work Peter Wadhams published a year and a half ago wherein he showed Arctic ice melt is 'like adding 20 years of CO2 emissions'. He based this assertion on calculations, as ca...
Arctic Report Card 2013 press conference at AGU Fall Meeting:
http://www.youtube.com/watch?v=dZZsTgl-jHQ
Arctic warming -> extreme weather debate
Andrew Freedman outdid himself on Climate Central with an excellent overview of the scientific debate on the link between Arctic sea ice loss and a wavy jet stream causing weird and extreme weather. Coincidentally (?) there's an "extreme kink" in it right now that just caused the warmest Decemb...
SH,
Nicely put.
The strength of positive and negative feedbacks will determine the outcome, together with the GHG-forcing. And it seems we all do not know enough about how the ice caps will respond to this kind of forcing. GIS also seems to have two glacier fjords which extend deep into the interior of the ice cap, at Jakobshavn and Petermann glaciers. So although WAIS seems more unstable than GIS, this may be a pretty vulnerable ice sheet as well.
Pinpointing the minimum
UPDATE September 16th: Given another uptick and the current weather forecast, I'm ready to call the minimum for IJIS SIE V1 on September 12th at 5,000,313 km2. Apparently the high was too big and the pressure gradient too low to prolong things (see below). --- This blog post should perhaps ha...
"Even more than doubling the current average melt rate to 400KM3/year we are still looking at a minimum of 700 years for the cap to melt out."
You mean 7000 years, I suppose. Then again, over the past three years GIS lost about 400 km3/yr on average. Let's say this will continue until 2020. And then could this double in another 20 years to 800 km3/yr from 2020-2040? And then again to 1600 km3/yr from 2040-2060, and again to 3200 km3/yr from 2060-2080? Then the rate would be about 9 mm/yr of SLR contribution from GIS. If that rate could be sustained, with positive and negative feedbacks about in balance, then it would take about 700 years for near melt-out of GIS.
I don't know if this is possible. And the risks for Antarctica seem higher. But scientists like Jim Hansen do suspect such accelerations could be possible under BAU. So I think it's too early to completely dismiss such scenarios.
Pinpointing the minimum
UPDATE September 16th: Given another uptick and the current weather forecast, I'm ready to call the minimum for IJIS SIE V1 on September 12th at 5,000,313 km2. Apparently the high was too big and the pressure gradient too low to prolong things (see below). --- This blog post should perhaps ha...
Peter,
We're all wondering the same. Part of the scientists seems to think it will take at least a thousand years. Another part seems to fear it may take as little as three or four centuries, if we continue with BAU.
Pinpointing the minimum
UPDATE September 16th: Given another uptick and the current weather forecast, I'm ready to call the minimum for IJIS SIE V1 on September 12th at 5,000,313 km2. Apparently the high was too big and the pressure gradient too low to prolong things (see below). --- This blog post should perhaps ha...
Was it 40 cm of ice, or snow? Or a combination?
ASI 2013 update 6: major slowdown
During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily Cryosphere Today sea ice area (SIA) and IJIS sea ice extent (SIE) numbers, which I compare to data from the 2005-2012 period (NSIDC has ...
The Colbert Report reported on 'the lake at the North Pole':
http://www.colbertnation.com/the-colbert-report-videos/428206/july-30-2013/smokin--pole---the-quest-for-arctic-riches--north-pole-lake
ASI 2013 update 6: major slowdown
During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily Cryosphere Today sea ice area (SIA) and IJIS sea ice extent (SIE) numbers, which I compare to data from the 2005-2012 period (NSIDC has ...
Look at figures 3, 4 and 5 in Bamber et al 2013, as linked above earlier:
http://www.the-cryosphere.net/7/499/2013/tc-7-499-2013.pdf
On pp.506-507 they say, as also cited above:
“In the Jakobshavn catchment, there is a dendritic channel system extending for about 325 km from the current grounding line into the interior almost as far as the ice divide. It seems likely that this is a palaeo-fluvial feature that predates ice cover in Greenland and may be important for subglacial water routing… The width of the trough is 3–4 km and the region of fastest flow coincides fairly well with the location of the deepest ice. The trough is 1366m below sea level at its deepest point compared to a maximum depth over the entire region of 556m below sea level in the older dataset. The main trough of Jakobshavn Isbrae is not continuous in the new dataset, disappearing around 100 km and reappearing at about 140 km. This does not imply that the trough is discontinuous, but only that there are insufficient data to confirm the trough’s presence or otherwise in this region.”
So it seems there may well be a connection below sea level into the interior bottom of the ice sheet. Looking at their figure 3a this may also be the case from Petermann Glacier into the interior.
Greenland Ice Sheet: "Starting to Slip"
Peter Sinclair from the ClimateCrocks blog has produced a new video for the Yale Forum on Climate Change & the Media with some good speakers:
From Bamber et al 2013 (linked above), pp.506-507:
“In the Jakobshavn catchment, there is a dendritic channel system extending for about 325 km from the current grounding line into the interior almost as far as the ice divide. It seems likely that this is a palaeo-fluvial feature that predates ice cover in Greenland and may be important for subglacial water routing… The width of the trough 3–4 km and the region of fastest flow coincides fairly well with the location of the deepest ice. The trough is 1366m below sea level at its deepest point compared to a maximum depth over the entire region of 556m below sea level in the older dataset. The main trough of Jakobshavn Isbrae is not continuous in the new dataset, disappearing around 100 km and reappearing at about 140 km. This does not imply that the trough is discontinuous, but only that there are insufficient data to confirm the trough’s presence or otherwise in this region.”
So maybe warming ocean water could in time eats it way into the interior bottom of the ice sheet?
Greenland Ice Sheet: "Starting to Slip"
Peter Sinclair from the ClimateCrocks blog has produced a new video for the Yale Forum on Climate Change & the Media with some good speakers:
More...
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