Messages

101

Arctic sea ice / Re: What the Buoys are telling

« on: June 08, 2015, 10:51:58 PM »

I think thats pretty much spot on Andreas, and it looks like it will continue to move pretty fast during this entire week.

Wonder if O-buoy8 is going to be redeployed this year, it was recovered from the arctic in 2013 and has briefly started reporting again such as every O-buoy does before it hits the ice later in the year.

Edit; And 2015b is in trouble, at least there be will one ablation stake left.

102

Arctic sea ice / Re: The 2015 melting season

« on: June 08, 2015, 09:49:28 PM »

When I said in the latest ASI update that I thought the cyclone might get the ice in the Laptev and East Siberian Seas on the move, I wasn't expecting for the fast ice near the New Siberian Islands to break up already!

It is certainly quite early, but not as much as it might seem. These melt pond related (i presume) low concentration areas are actually such an usual occurrence on the fast ice south of the New Siberian Islands that the average Uni-Bremen ice concentration there is significantly lower on 16. June than it is on 1. July.

103

Arctic sea ice / Re: The 2015 melting season

« on: June 04, 2015, 01:20:21 PM »

The arctic sea ice snow cover is about to be torched.

Snow depth forecasts have proven notoriously unreliable time and time again, and I honestly don't see where the heat to melt all that snow should be comming from. According to ECMWF most of the central basin is going to be rather cold during the next 3 days, with the exception being Laptev and ESS, then the 96h-144h range is as unfavorable to melt as it can possibly get, LP activity and virtually no warm air intrusion at all. Only in the fantasy forecast range, 168h and beyond, does it seem like widespread melting will return to several important regions.

104

Greenland and Arctic Circle / Re: Jakobshavn Isbræ / Sermeq Kujalleq / Ilulissat Icefjord

« on: June 04, 2015, 12:57:03 PM »

Thanks A-Team. Wonderful as usuall.

105

Arctic sea ice / Re: The 2015 melting season

« on: June 03, 2015, 10:41:05 PM »

Posted below is the average concentration map for 2. June (2002-2014) as well as a comparison to 2015. The third attachment is a direct comparison between 2012 and 2015.

Beaufort is still below average, but the lack of ice there no longer seems unprecedented. Very strange melting pattern in Hudson meanwhile, and I think Cesium62 is right that it is the most important reason why CAPIE/compactness is abnormally high. Laptev and Baffin is still lagging behind slightly, while Chukchi and Kara are quite far ahead at the moment.

The perceptive reader might notice the rather funny looking geographical shapes in the last map. This is because 2012 is only available in SSMIS, which is also the reason why that year is not included in my average maps. Though, interpreting this data from 2012 leaves me with the impression that a large portion of the difference in extent between 2012 and 2015 is because of Bering sea, and if I were to make a judgement exclusively based on this comparison (which is of course a highly dubious decision) then I would say the pack was in a worse shape three years ago.

106

Greenland and Arctic Circle / Re: Jakobshavn Isbræ / Sermeq Kujalleq / Ilulissat Icefjord

« on: June 02, 2015, 11:20:19 PM »

Speaking of campsites just got me wondering; how long will it take before the first rock peak through the ice sheet on the opposite side (east/northeast) of the main channel? I guess it has been of greater interest to measure the ice thickness in the main trench rather than the surrounding high ground, but is it possible to get good idea of how thin the ice is there and how long it will take before its gone?

107

Arctic sea ice / Re: The 2015 melting season

« on: May 31, 2015, 01:01:45 PM »

I don't think the jump in water temps at 2015A is to be associated with discharge from the Mackenzie River though. Since the buoy sits so close to the shore it is likely the water comes from a more local source like Kuparuk River or Colville River.

108

Arctic sea ice / Re: What the Buoys are telling

« on: May 28, 2015, 08:00:10 PM »

That's real heart-attack snow. The kind you don't bother to clear from your driveway because a) you'd probably kill yourself trying to shift more than a few square feet of it, and b) it's so wet that it's almost certain to have disappeared by the time you get home from work.

I agree, but it didn't look that way yesterday, certainly not on the pic posted by Andreas. Really interesting situation.

Meanwhile on O-buoy 12, slightly further north in the same area, there is sun and some visible surface melt.

109

Arctic sea ice / Re: What the Buoys are telling

« on: May 27, 2015, 01:04:07 PM »

20 cm of fresh (and wet?) snow just fell on 2015b

110

Arctic sea ice / Re: What the Buoys are telling

« on: May 22, 2015, 07:54:23 PM »

Buoy 2015B, somewhere deep in the Beaufort/Chukchi region

Everything seems to be falling apart around this buoy at the moment, suddenly the crack was transformed into an ocean of slush. It can't be too many weeks before the camera starts bouncing around.

111

Arctic sea ice / Re: The 2015 melting season

« on: May 21, 2015, 10:53:49 AM »

So have the weather models backed off on that heat wave spanning much of the central Arctic basin?

Yes, the models have backed down slightly, but only the less reliable longer term forecast I would say (after all it is more that 3 days since the heat looked bound to stay forever). To me the ECMWF looks a bit 2014ish with lots of HP activity in the central basin, but without that much heat intrusion, so it looks a bit strange that GFS is throwing melting temps all over the central basin in the 120h-180h range. I think GFS will back down from that and the melt during the next 2-7 days will mostly be confined to the peripheries, as one would expect to be the case in May.

112

Arctic sea ice / Re: The 2015 melting season

« on: May 18, 2015, 04:07:59 PM »

These are the average concentration (2003-14 from Uni Bremen) and the 2015vs average maps for May 15th. Quite some negative anomaly in Kara, Hudson as well as Beaufort obviously, while melting continue to lag behind in Baffin. Laptev is also starting very slow this year, and I recon this trend is set to continue as the heat keeps being directed toward Beaufort and surrounding areas.

Click to enlarge.

113

Antarctica / Re: Rift in Larsen C

« on: May 14, 2015, 12:07:58 PM »

These numbers do not make sense to me, the surveyed lowering is abt. 6.6cm per year of which 28cm per year is ice-loss?

I would guess that the lowering of the ice only reflect a fraction of the total melting/thinning since most of the ice is resting below the water line. Maybe a slightly clumsy way to present the numbers.

114

Arctic sea ice / Re: The 2015 melting season

« on: May 12, 2015, 12:11:08 AM »

Neven: just checked the ECMWF 12z run and to me it seems like it is backing somewhat from the warm air intrusion.

Not quite sure why you think so LMV, seems to me like the likelihood of heavy melting in Beaufort and Chukchi is increasing with the latest ECMWF run as well. Kind of strange looking dipoleish setup, and of course very interesting.

115

Arctic sea ice / Re: The 2015 melting season

« on: May 10, 2015, 12:51:50 PM »

Agree friv. If snow cover in the western corner of NA doesn't crash during the next week then I will altogether give up trying to predict snow cover.

116

Arctic sea ice / Re: Arctic Image of the Day

« on: May 09, 2015, 09:19:28 PM »

Can we see  Greenlandic mountains from the O-Buoy 9?

The shore is only about 70-80 km away so it has to be Greenland. And that is really cool.

117

Science / Re: Mauna Loa CO2

« on: May 06, 2015, 11:14:20 PM »

The attached NOAA plot for CO2 concentrations through the end of April 2015, indicates (to me at least) that for the Feb, March & April 2015 atmospheric CO2 concentrations have accelerated faster than in any comparable period for the past several years.

Probably linked to the El Nino in the offing. Hotter ocean water can absorb less CO2 iirc, so as the ocean water gets hotter more CO2 is pumped out?

Pmt111500 made an excellent post about a year ago (reply #204) which suggests that there have recently (since 2011) been a significant acceleration in year to year increases even when the ENSO-signal is removed. I would love to have that graph updated by the way.

118

Arctic sea ice / Re: The 2015 melting season

« on: May 02, 2015, 07:46:59 PM »

Attached below are two maps showing the average sea ice concentration on 1. May for the last decade or so (2003-2014 with 2012 not included) and how 2015 compare to the average for this day.

Bering sea stands out as slightly below normal (the distribution of ice in this region seems a little bit odd), while on the other hand, ice extent in Baffin is way above average. Most regions are pretty close to the norm though, and the amazing anomaly in Okhotsk from previously this winter is virtually gone. Note as well that smaller breakups in Beaufort/Amundsen Gulf is unusual, but not entirely unprecedented this time around.

NB: False ice along the coasts has been removed in areas without proper ice cover (from the end products only!), this includes most of the ice in The Great Lakes and St. Lawrence of whom some might have been real ice. I would presume these are areas of minimal interest.

Click on the pictures to get the full Size.

119

Arctic sea ice / Re: The 2015 melting season

« on: May 01, 2015, 11:48:49 PM »

The latest runs do indeed look 2013ish, but extensive ponding isn't to be expected in the central basin for a few weeks so I don't think a week or two of cyclonic activity will be able to cripple the entire melting season. Rather to the opposite, it now looks increasingly likely that there will be extensive melting of both snow and ice in peripheral regions during the coming week (as the cold air gathers in the high latitudes), snow cover has already taken a beating according to Rutgers.

120

Arctic sea ice / Re: The 2015 melting season

« on: April 30, 2015, 12:50:46 AM »

2-3 days of southerly winds and warm temps in Kara should have some impact, but not more than that I would guess. I find it perhaps more interesting that the HP setting up those winds seems to get stuck over Siberia where it could potentially cause very intense snow melt over a broad area. Very interesting to see how the models develop over the next 3-4 days.

121

Consequences / Re: Global Surface Air Temperatures

« on: April 29, 2015, 07:44:28 PM »

UAH released their version 6 dataset.

Shockingly, it changed the 36 year trend from .14C/decade to .114C/decade (a reduction of nearly 20%).  It is particularly notable given how long this trend line is. This is a major revision of the TLT temperature trend and in my mind, casts significant doubt on the continued viability of remote sensing for trends.  How anyone could use UAH/RSS for empirical studies with this type of uncertainty and revision is beyond me.  For example, Feb 2015 had it's anomaly changed from 0.28 to 0.11C. WOW.

http://www.drroyspencer.com/2015/04/version-6-0-of-the-uah-temperature-dataset-released-new-lt-trend-0-11-cdecade/

Oh my, thats a lot, so much that celebrations have already started in the denialosphere I can sense, another straw they can cling on to.

122

Greenland and Arctic Circle / Re: Independence Fjord / Hagen Fjord / Danmark Fjord / North Greenland

« on: April 19, 2015, 04:58:34 PM »

Much more calving activities where seen around 1985 and it looks like Acedemy has come to a point where calvings are rare, maybe we are at the grounding line already?

Apparently, the front of the Academy Gletscher as well as a substantial part of its trough is below sea level (see nr. 163 on page 35).

http://www.nature.com/ngeo/journal/v7/n6/extref/ngeo2167-s1.pdf

It could of course be just a tiny channel without much relevance.

123

Arctic sea ice / Re: The 2015 melting season

« on: April 17, 2015, 01:51:45 PM »

While there are some mild pockets over the Arctic during the next few days, such as in the Barents/Kara sector now and Beaufort early next week, these aren't quite mild enough to cause dramatic melting yet.

I, agree about that, but there seems to be some pretty strong winds setting up over beaufort in that 48h-144h period. Wouldn't be surprised to see significant polynyas opening up along the coast before -NAO is forecasted to appear. I do as well expect some significant snow melt in that part of the hemisphere, 7C and sprawling sunlight should be hitting as far north as Inuvik on Monday, thats a solid 12 degrees above the average high.

124

Arctic sea ice / Re: The 2015 melting season

« on: April 17, 2015, 12:11:52 AM »

According to Wipneus:

The "torch" is on over the Hudson bay.

Hm, I see its there today as well. It is just wet snow I suppose and not full melt ponding? Either way, I'll try to be more careful next time .

125

Arctic sea ice / Re: The 2015 melting season

« on: April 16, 2015, 12:33:45 AM »

Siffy, if you want to compare sea ice I suppose it is better to do an animation, or maybe something like this .

Certainly less ice in Barents and Kara now compared to one year ago, but its still April and we are just getting started way out there on the edges, so I personally don't see very much useful information in such comparisons right now. Better have the patience to wait another month at least.

And yes; that thing in Hudson is mainly an artifact.

126

Arctic sea ice / Re: The 2015 melting season

« on: April 08, 2015, 05:49:42 PM »

I would be careful about trusting those snow cover forecasts too much. Predicting how much snow that is going to melt is a difficult exercise and I suspect there is quite some uncertainty range in those forecast maps. It will be interesting to see how reliable this new cci feature turns out to be.

127

Greenland and Arctic Circle / Re: Kangerdluqssuaq Gletscher / Kangerdluqssuaq / East Greenland

« on: April 08, 2015, 01:21:58 PM »

I recall seeing similar numbers (8,1k a year) from a 2014 paper linked in the Jakobshavn thread. Maybe its the same measurements, but 35-40 m/day at this time of the year still seems very fast. About a doubling in annual average speed I would presume.

128

Arctic sea ice / Re: The Plateau Hypothesis

« on: April 08, 2015, 12:02:43 AM »

I think I  have my posts fixed, unfortunately any post  that  has copied them I  can't fix.  It  was a google+ setup thing.

Thanks, it easier to see what you mean now.

129

Arctic sea ice / Re: The 2015 melting season

« on: April 02, 2015, 11:10:04 PM »

Attached below is the average sea ice concentration of the 11 previous SIA maximums (2012 not included because it is only available in SSMIS) together with a comparison to this years early maximum.

One can see that the pacific side stands out as way below average, while there is lots of positive anomaly on the Atlantic side of the Arctic, Labrador/St Lawrence in particular. Notice that in Okhotsk there was at maximum more ice than usual close to the northern coast, which should give a clear indication that the record low SIA in this region is at least partly due to a lack of offshore winds.

Caveat; false ice along the coast has not been removed from any of the pictures.

Click on the picture for full resolution

130

Antarctica / Re: Will Antarctica sea ice set a new record in 2014?

« on: April 01, 2015, 02:21:51 AM »

The two attachments posted below display the average sea ice concentration at maximum for the period of 2002-2013 and furthermore how the record breaking maximum in 2014 compared to this average. Notice amongst other things how abnormally large the coastal polynyas were in 2014.

131

Arctic sea ice / Re: 2015 sea ice area and extent data

« on: March 16, 2015, 03:45:50 PM »

After a recent dip, the negative anomaly in the sea of Okhotsk is now below 0,5 million square km which means that the previous all time record anomaly in this region has been pulverized. It also appears that the winter max there is going to be lowest ever with a margin of more that 100 000 km^2.

132

Greenland and Arctic Circle / Re: Jakobshavn Isbræ / Sermeq Kujalleq / Ilulissat Icefjord

« on: March 07, 2015, 10:42:02 PM »

What is to be made of the very large overdeepening to the south east of JI running in almost opposite direction of the other channels in the JI paleo drainage system? It seems a bit misplaced.

133

Antarctica / Re: Will Antarctica sea ice set a new record in 2014?

« on: March 04, 2015, 03:09:54 AM »

Thank you Jim. A regional breakdown of Antarctic SIA/SIE is something I have been missing.

134

Greenland and Arctic Circle / Re: The Nares Strait thread

« on: February 09, 2015, 12:51:13 AM »

but it may loosen up the Kane bottleneck, which is the topic of discussion here.

I would assume the primary reason why hot weather should affect Nares is that such weather will likely be accompanied by strong winds, and right now, really strong winds would be the only thing that could possibly make Nares move again. However, I don't see that coming in the forecast.

Just let it go dog. It's over .

"I fear, Baldrick, that you will soon be eating those badly chosen words." Edmund Blackadder

I can assure you that right now all possible measures are being taken to eat those words .

135

Greenland and Arctic Circle / Re: The Nares Strait thread

« on: February 05, 2015, 01:20:04 AM »

but it may loosen up the Kane bottleneck, which is the topic of discussion here.

I would assume the primary reason why hot weather should affect Nares is that such weather will likely be accompanied by strong winds, and right now, really strong winds would be the only thing that could possibly make Nares move again. However, I don't see that coming in the forecast.

Just let it go dog. It's over .

136

Greenland and Arctic Circle / Re: The Nares Strait thread

« on: January 04, 2015, 03:07:45 AM »

There you go SH. Hidden away in the "Home brew extent" thread was this most interesting link to Dr. Munchow's blog, which should answer your question.

http://icyseas.org/2012/06/19/nares-strait-ice-bridge-and-arctic-ice-thickness-change/

To sum it up with the same quote that TerryM chose back then.

"I processed and archived maps of Nares Strait satellite images to guide 2003-2012 analyses of how air, water, and ice change from day to day. Ice arches formed as expected during the 2003/04, 2004/05, and 2005/06 winters lasting for about 180-230 days each year. In 2006/07 no ice arch formed, ice streamed freely southward all year, and this certainly contributed to the 2007 record low ice cover. In 2007/08 the arch was in place for only 65 days. In 2009/10, 2010/11, and now 2011/12 ice cover appear normal as the arches formed in December and lasted until July."

137

Greenland and Arctic Circle / Re: The Nares Strait thread

« on: January 04, 2015, 02:23:39 AM »

Has there ever been a freeze season where the Nares transport simply did not shut own?

I recall that this is a topic which has previously been up for discussion in this thread, or at least somewhere on the forum, with the conclusion being that there has been a couple of winters in which proper arches have failed to establish. Can't remember the exact years, but I'm sure that others do.

138

The rest / Re: How do you get here? - from there???

« on: January 03, 2015, 02:36:49 AM »

Brilliant post JimD. Thank you.

If birth control were as convenient to obtain as Viagra, and women had independence and control over their own bodies, the world's population could stabilize normally.

I will have to object to such a notion. You can't really fool evolution or human nature that way in the long run. To quote JimD:

Population levels are driven by available per capita energy supplies

If you want to permanently stabilize the world population you would either have to impose direct birth control (Chinese style), or deny people access to more energy (i.e. starve them).

139

Arctic sea ice / Re: Arctic Refreeze Discussion: 2014/2015

« on: November 13, 2014, 02:02:44 AM »

Delta maps for the 10th of November reveals that the refreeze in eastern ESS appears rather slow this year, the same also seems to be the case in Baffin. Though, as one might expect, Barents/Kara is still quite a bit ahead of most years (I'm amazed by how much 2012 refreeze was postponed in this region, didn't remember it was that bad).

The forth year of comparison this week is 2008 (in addition to 2007, 2012 and 2013 respectively). A year which in general saw abnormally much SIA and SIE around this date.

140

Consequences / Re: Global Surface Air Temperatures

« on: November 08, 2014, 11:55:47 PM »

I don't think you should read to much into those la-nina recovery number Michael. The difference between a moderate, or rather strong nino (like 2002 and 2010 respectively), and a ninoish year like 2012 (a year which actually begun as a weak nina), can be quite significant and quite easily account for 0,15C I think. Then, for some of the events in the 80s and 90s you also have volcanic interference.

Don't know how many of you is following daily amsu temps on a regular basis anymore.
http://ghrc.nsstc.nasa.gov/amsutemps/
I still find it rather amusing, even though ch5 ultimately collapsed in 2013, but how reliable are these numbers in general (and then ch6 in particular)?

141

Arctic sea ice / Re: Arctic Refreeze Discussion: 2014/2015

« on: November 08, 2014, 11:53:14 AM »

The euro is also quite harsh, it seens that an initial wave of warm air from the masive bering storm eventually will result in a cutoff system over Alaska, (120-144h range), then in the 168h+ range this cutoff high meanders deep into the arctic, basically pushing all the cold down Canada and Siberia. The Pacific refreeze will certainly be delayed quite a bit, and if the forecast go all the way (which is of course a bit unlikely), some seriously high 80N temps should be expected.

142

Consequences / Re: 2014 El Nino?

« on: November 06, 2014, 11:53:23 PM »

According to the link provided by BigB, -85.72 (31th May 1997) seems to be the lowest one-day SOI value since 1991, so it is perhaps a little bit early to pop the champagne just yet. On the other end of the scale you find +74.55 (1st April 2011).

143

Greenland and Arctic Circle / Re: Jakobshavn Isbræ / Sermeq Kujalleq / Ilulissat Icefjord

« on: November 03, 2014, 01:15:52 AM »

Interesting: the south branch advanced quite a lot while the north branch did not advance at all during this period

The northern branch, especially its eastern part, is virtually stuck on land, so it should not come as a big surprise that it advances very slowly even though it is noteworthy. I would love to see some physical depth measurements taken from the edge of the north branch, but I suspect that anyone taking on such a task might run into some serious problems (such as health and safety requirements).

It is also noteworthy that the "third branch" appears to be advancing fairly rapidly, although the crevasses and apparently low lying ice edge makes it a little difficult to establish exactly how much ice is exiting there.

144

Arctic sea ice / Re: The Slow Transition

« on: October 30, 2014, 09:59:50 PM »

Thank you very much for correcting crandles, I didn't realise that all the data was wrong (even though captain hindsigth says we should have noticed ).

145

Arctic sea ice / Re: The Slow Transition

« on: October 30, 2014, 12:49:12 PM »

512 Km^3 divided by area 936000 km^2 per wikipedia which might well be different to the area being used seems to suggest a little over 50cm average thickness rather than 5 metres?

But hold on a second. This was the minimum, right? According to CT the ESS SIA around minimum was somewhat below 100000^2, and if I'm not completely mistaken 936000 km^2 would be the SIA during winter max. It is otherwise a great piece of information that looks to be perfectly correct, but if you are talking about the same ESS as I am (from CT), then I'm pretty sure the 2014 min volume is a mistake that should be corrected.

EDIT: I did perhaps not make it clear enough in my first post that I was only talking about the 2014 min volume.

146

Arctic sea ice / Re: The Slow Transition

« on: October 29, 2014, 07:46:51 PM »

Jdallen, are your numbers suggesting that average thickness at minimum was over 5 metres? That I do not believe, nor that ESS volume at min was 5 times higher than 2013.

147

Arctic sea ice / Re: Arctic Refreeze Discussion: 2014/2015

« on: October 28, 2014, 05:27:11 PM »

The amount of ice in Kara is really standing out at the moment, continuing this seasons trend of above normal amounts of "Atlantic ice". On the other end of the scale, the ESS is now lagging behind three out of the four years and there is still an apparent lack of export through farm. Refreeze has also begun in Baffin where the amounts of ice seems on pair with those of recent years.

In addition to 2007, 2012 and 2013, I've this week added a comparison with 2010.

148

Arctic sea ice / Re: Five Year Cycle Thread

« on: October 25, 2014, 01:51:45 PM »

What causes the whole system to leave an all–time low YAE in 2006 to go to a new low in 2007 and then higher than 2006 in 2008 and 2009 before ending up roughly equal to 2006 in 2010, would be fun to hear thoughts about.

This effect is most certainly caused by the low winter extent in 2006 and 2007. Why 2006 in particular had such a low extent throughout the entire winter is not easy to answer, and it might perhaps be random. Extent in Bering can be PDO related, which may explain some of the recent rebound in winter extent, but this rebound is also partly caused by Baffin/Newfoundland. It might be a little bit far fetched to relate that region's winter extent to increased freshwater runoff from glaciers (both CAA and Greenland), I don't know how much difference it could really make.

149

Consequences / Re: 2014 El Nino?

« on: October 23, 2014, 02:58:21 PM »

52 months have now passed since last El niño expired. That is the longest such period since the recording began in 1950 (previously, 50 months was the longest niño free period).

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml

150

Arctic sea ice / Re: Arctic Refreeze Discussion: 2014/2015

« on: October 22, 2014, 04:09:31 PM »

Since the snow cover extent has been soaring lately, I made a snow cover comparison similar to those I made earlier this spring. Though, I'm not sure how informative they are since I personally find them a little bit messy and chaotic this time.

The pics are 2014, 2013 and 2012 respectively, I believe the date is October 19th, but since CT labels the maps in its compare tool with different dates than those in its archive, it is hard to be sure (the CT archive appears in general quite flimsy, as random dates and entire section are missing everywhere). Reds are decrease, blues are increase.