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John Christensen
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Related to warm sea water undermining west Greenland glaciers, though different from the situation at Petermans Glacier: If you play the sequence of the Greenland accumulated surface mass balance (SMB) from Sept. 1, 2016 to now, you will notice how the area feeding the Jacobshavn Glacier develops a negative anomaly already in Sept. '16 and how this negative balance has grown in the past year: By now, the entire area feeding into the glacier valley has a significant negative mass balance, while Greenland overall has received a significant surplus of precipitation in the past year. Even the front hills left and right of the Jacobshavn Glacier glacier front have a positive anomaly.. It seems clear that this area is impacted not so much by air temperature or precipitation deficit, but by increased glacier speed, which again most likely is caused by (warm) sea water still reaching further underneath the glacier.
Thanks Jim, had not noticed that! Yes, navegante; surface temps are starting to creep downwards ever so slowly in the high north - will be interesting to see how this next (last?) summer storm plays out.
Toggle Commented Aug 7, 2017 on PIOMAS August 2017 at Arctic Sea Ice
Great update, thanks Neven! I agree with the conclusions so far, but the deepening of the low this coming week will result in mixing with warmer surface waters, and with the Arctic sun descending we will start seeing more negative impact from the storms. Too bad we no longer have the compactness ratio: Have you given thought to using arctic-roos area divided by arctic-roos extent to have some indicator on this? Seems very compact this summer..
Toggle Commented Aug 7, 2017 on PIOMAS August 2017 at Arctic Sea Ice
Still 5-6 days out, but ecmwf is forecasting an intense low just north of the CAA.
Toggle Commented Aug 4, 2017 on PIOMAS July 2017 at Arctic Sea Ice
Welcome to you Tony! To your question: Yes, clouds and general low pressure is the norm for the Arctic during summer months, primarily due to cold surface temps compared to surrounding continents - quite similar in fact to sea clouds appearing off the cost of Oregon due to cold Pacific surface temps. Specific to the Arctic, Neven put together some great info here:
Toggle Commented Aug 1, 2017 on PIOMAS July 2017 at Arctic Sea Ice
Hi Rob, I would agree with Neven: In recent years area and extent has gone so low that it could cause a decrease in volume melt rate for remaining ice. Reflecting a drawn out end to summer ice rather than a sudden crash possibly.. A separate observation for this season is an apparent reduction in north-bound sea current in the eastern Fram Strait: We have in recent years seen wide open water to the north-west/north of Svalbard, but this area got filled with south-bound sea ice early in the year and has stayed ice-filled, which to me seems to indicate a reduction in north-bound sea current, but also could be due to an increase in south-bound sea ice flow. A reduction in sea current would better explain the slight increase in sea ice in northern parts of Barents as well, so is where I am leaning, but have seen no news on Fram current.
Toggle Commented Jul 13, 2017 on PIOMAS July 2017 at Arctic Sea Ice
Thank you very much for the melting momentum update Neven! I would agree with Dr. Schroder that we should see slightly below average sea ice meeting this season due to lower melt pond fraction, seeming caused by lower than average high north temps (DMI 80N). I am also very curious about the impact of Greenland, which often is given little space for consideration for the sea ice: The relentless storms last fall has caused much higher precipitation than usual ( ), and the measured albedo of Greenland has improved as a consequence. In 2012 we saw the heat dome over Greenland, which caused very warm air to flow down to surrounding sea surfaces, but this year the ice cap will help keep things temperate. Back to lurking.
Toggle Commented Jun 19, 2017 on Melting momentum: May 2017 at Arctic Sea Ice
I'm sure the bear was praying that news of the latest Russian Arctic military base and additional nuclear ice breakers was just a bad dream..
Toggle Commented Apr 20, 2017 on Praying polar bear at Arctic Sea Ice
Coming SSW event? I noticed on the DMI forecast that temps just north of the CAA may dip below -40C on Jan. 7th. As such a low temperature is rather unusual for recent years, I was wondering if this might be related to a sudden stratospheric warming event?
Toggle Commented Jan 4, 2017 on PIOMAS December 2016 at Arctic Sea Ice
I fully concur with you Susan; the value of this blog stems from Neven's character, being insightful, communicating clearly, but most importantly from a high degree of respect for other people's opinion. We can all learn from that, as the respect for other people will be necessary in making progress from this situation. The other character trait coming to the forefront now is the optimist/pessimist dimension, which a lot of the comments are hinting at. What Neven seems to be searching for, is the elusive combination of being aware of the situation, being respectful to others, while avoiding the pessimism - avoiding falling into despair. That may just require a glass of good wine and music at times..
Toggle Commented Dec 15, 2016 on PIOMAS December 2016 at Arctic Sea Ice
Neven, Are you sure the twitter quote was by Viddaloo? While I agree that he does not seem to be very reflective about the use of extrapolation or the interpretation of annual averages, he has been quite consistent since he opened a blog on Wunderground back in Nov. 2015: But if true, then Dr. Jeff Masters should check the blog account on his site also.
Toggle Commented Dec 13, 2016 on PIOMAS December 2016 at Arctic Sea Ice
Neven, It seems like I have become more successful in lurking than you have yourself.. ;-) That said; I admire your desire to keep the ship leveled O Captain my captain!
Toggle Commented Dec 13, 2016 on PIOMAS December 2016 at Arctic Sea Ice
Neven, In agreement with the many comments above: Thank you very much for having managed this great blog with an even-keeled approach to understanding and communicating changes for the Arctic sea ice. Wishing you well and good luck with the continued house project! Kind regards, John
Toggle Commented Dec 6, 2016 on Sabbatical (I hope) at Arctic Sea Ice
OK viddaloo, so then you also agree that for the majority of the time since the Sept minimum and currently, we have slightly more sea ice volume than in 2012?
Toggle Commented Nov 16, 2016 on PIOMAS November 2016 at Arctic Sea Ice
"Yes, I remember! And I'm very happy they went through the trouble of improving their model so that it would become more reliable. If only PIOMAS would do the same, and listen to well–founded criticism!" That is just great, viddaloo, and then since DMI apparently listened to well-founded criticism (Did they?) do we now agree that 2016 has had more sea ice than 2012 for the vast majority of the time since minimum in September? - because we now like the DMI volume model more than the PIOMAS volume model..
Toggle Commented Nov 16, 2016 on PIOMAS November 2016 at Arctic Sea Ice
"2016 minimum Arctic sea ice volume was lowest ever according to DMI" viddaloo, Remember that we were in agreement earlier that the DMI volume model is not reliable, so would it make a difference if it is lower or higher than 2012?
Toggle Commented Nov 15, 2016 on PIOMAS November 2016 at Arctic Sea Ice
Politics is becoming more polarized with both sides screaming at each other - until one or both sides take up more tangible means to defeat the other. This is the scary part.
Toggle Commented Nov 10, 2016 on PIOMAS November 2016 at Arctic Sea Ice
Couldn't agree with you more NeilT - except that Trump should be successful in just ignoring climate change on his watch as he is supported by the type of voters, who wants cheap and plenty gas at any cost. These guys removed the Indians and the buffalo, so no reason why they would feel any different about ice bears or flooding of coastal areas.
Toggle Commented Nov 10, 2016 on PIOMAS November 2016 at Arctic Sea Ice
Thank you for another great update Neven - and best wishes for your other endeavors! Otherwise, what a sad day for moderates: What happened in the US last night is just a continuation of what we have seen in Europe, Turkey, the Middle East and the Philippines over the past few years. The consequences will not be positive for the climate/energy problems or for humans.
Toggle Commented Nov 9, 2016 on PIOMAS November 2016 at Arctic Sea Ice
But yes; most of North America and the central Arctic very warm indeed:
The 'Siberian' cold actually stretches from Morocco to the West Siberian Plain and then again across much of eastern Siberia to Kamchatka. And now the sea ice is causing this weather, not the AO. Great!
wayne, you think PIOMAS is for the uncritical fixated minds, while the erratic noise of Jaxa volume is for the insightful? May peace reach your mind.
Jaxa 2014 volume increased from about 4.000km3 to 11.000km3 during the month of August. With such erratic movement, it is not useful for metrics.
Hi viddaloo, Jaxa does not produce reliable volume numbers, as you can see from the very high up and down ticks. PIOMAS is normally recognized as the most reliable option, so you should use that volume.