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Arctic Sea Ice Discussion 2016-2017: The Refreeze.

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4 hours ago, Gray-Wolf said:

I guess they used to say that about Barrentsz back in the 1930's when it blocked access to the basin with its mountainous paleocryistic ice ( as reported from the Norwegian expeditions there over the late 30's). We should be mindful that the Atlantic bottom waters, just below the surface layer, holds enough heat to keep the Arctic ice free year round ( as we saw in the PETM?). The more we see open water the more we see Low pressure systems mix out more and more of the thermocline ( ?)  meaning that , over time, that heat and salinity will make its presence known at the surface ( maybe the edge, across Fram, will edge ever poleward leaving Svalbard ice free year round?).

We know , from the PETM flaura/fauna that Arctic night temps did not dip below 10c on Ellesmere Island even with 24hr darkness??? It must have been a foggy old basin back then!!!

I believe the IPCC (correct me if wrong) are not predicting ice free (which is not really ice free) until the end of the century, and that is just for summer months. No real prospect, even on the more alarming sides, of winter ice vanishing.

From November 10th, it really won't matter so much what the weather is doing in the arctic. That sea ice total will just keep on rising and at or extremely close to the pace in other low years.

 

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3 hours ago, jvenge said:

I believe the IPCC (correct me if wrong) are not predicting ice free (which is not really ice free) until the end of the century, and that is just for summer months. No real prospect, even on the more alarming sides, of winter ice vanishing.

I think it's closer to mid century now, and that's using a 5 year mean of less than 1 million km2. However, most sea ice models have hugely underestimated ice loss so most experts think the first ice free September will arrive considerably sooner than that. We'd need warming of 10s of degrees C to get rid of winter sea ice, so not a likely prospect within our lifetimes. Doesn't negate the problems associated with diminishing sea ice cover in general though.

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12 hours ago, BornFromTheVoid said:

I think it's closer to mid century now, and that's using a 5 year mean of less than 1 million km2. However, most sea ice models have hugely underestimated ice loss so most experts think the first ice free September will arrive considerably sooner than that. We'd need warming of 10s of degrees C to get rid of winter sea ice, so not a likely prospect within our lifetimes. Doesn't negate the problems associated with diminishing sea ice cover in general though.

You are right, found it buried away in the AR5. I thought it was end of the century, probably from the report prior. 

What do you think will be the problems associated with sea ice cover though? Do you believe it will change the weather of Europe? USA? Obviously the ice by itself being there or not before there doesn't make a difference to anyone if you just consider the ice. Even the polar bears don't care much about it in summer and they sleep winter, so for them it is spring.

Edited by jvenge

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3 hours ago, jvenge said:

You are right, found it buried away in the AR5. I thought it was end of the century, probably from the report prior. 

What do you think will be the problems associated with sea ice cover though? Do you believe it will change the weather of Europe? USA? Obviously the ice by itself being there or not before there doesn't make a difference to anyone if you just consider the ice. Even the polar bears don't care much about it in summer and they sleep winter, so for them it is spring.

Starting from a local scale, reduced sea ice cover has several large impacts.

Much of the Arctic coastline is highly vulnerable to erosion, with some areas losing over 20m/year over the last few decades. A lot of the coast is comprised of permafrost soils, rather than bedrock, so they are extra vulnerable to erosion (and contain large amounts of carbon). Traditionally the sea ice would act as a buffer to waves and swells, and prevent the ocean surface from warming much. It also used to be that most Arctic coastlines, for example, the Beaufort coastline, would be exposed to open water for maybe 2-3 months of the year, which limited erosion rates. The Beaufort sea coast has been open since the end of April this year...
Anyway, all this means is that the reduced sea ice is resulting in bigger waves, bigger swells, storm surges and much warmer water, which is eating into the coasts at accelerating rates. You can just imagine what impact this is having, from infrastructure to wildlife and also the transfer of additional carbon to the air and water (some of the permafrost is like frozen bogland).

Looking slightly further afield, a warming Arctic means a warmer Greenland. This means increased melting, glacier calving and mass loss in general. This then leads to accelerated sea level rise and potential disruption of the thermohaline circulation.

As for altering our weather (other than through the changes to the THC), it certainly seems possible. From a basic standpoint, changing the ice cover and heating the Arctic will affect the interaction between the ocean surface and atmosphere, altering the weather patterns. Less cold air over the Arctic means less cold air to spill south, and more modifacation of the cold air as it passes over open water rather than sea ice.
At a more fundamental level, the temperature difference between the Arctic and lower latitude regions is one of the fundamental drivers of the weather we experience. If you begin to change that temperature gradient you will inevitably change the weather in some way. The exact mechanisms involved and how quickly they will become apparent is debatable (many already think the effects are clear, others disagree), but it's next to impossible to alter that temperature gradient without altering the weather patterns too.

Recent Arctic amplification and extreme mid-latitude weather

The Melting Arctic and Midlatitude Weather Patterns: Are They Connected?

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52 minutes ago, BornFromTheVoid said:

Anyway, all this means is that the reduced sea ice is resulting in bigger waves, bigger swells, storm surges and much warmer water, which is eating into the coasts at accelerating rates. You can just imagine what impact this is having, from infrastructure to wildlife and also the transfer of additional carbon to the air and water (some of the permafrost is like frozen bogland).

Any papers on this as observed? Sea ice in the arctic has declined for some 37 years, so I imagine there is something based on observations, rather than what could happen. Your linked one doesn't load. But please just studies and papers that explain how it is happening and happened, rather than what could happen. 

Also, warmer water isn't result of the ice melting, as when there is less ice more heat is radiated to space from the north pole. Quite interesting how it works, actually. So, the issue is what makes the water warmer to then melt the ice, rather than the ice melting making the water warmer, if that makes sense?

1 hour ago, BornFromTheVoid said:

Looking slightly further afield, a warming Arctic means a warmer Greenland. This means increased melting, glacier calving and mass loss in general. This then leads to accelerated sea level rise and potential disruption of the thermohaline circulation.

Wholeheartedly agree, but even as of 2016, models haven't been able to predict Greenland surface temperature from 1861 to present. It's quite unique in a way, as with a lot of tinkering the global one has seen some correlation, but Greenland remains stubborn in conforming. That said, considering what we know today wasn't able to predict the past, how can we have any confident it can reflect the future? However, I do agree that a sudden melting of the ice sheet there would cause issues. 

Re circulation and a possible shut down of the gulf stream, data from ADCP buoys indicate no observed slow down, so this slow down is actually only happening in models and in scientists hypotheses, rather than in observable evidence. 

1 hour ago, BornFromTheVoid said:

As for altering our weather (other than through the changes to the THC), it certainly seems possible. From a basic standpoint, changing the ice cover and heating the Arctic will affect the interaction between the ocean surface and atmosphere, altering the weather patterns. Less cold air over the Arctic means less cold air to spill south, and more modifacation of the cold air as it passes over open water rather than sea ice.
At a more fundamental level, the temperature difference between the Arctic and lower latitude regions is one of the fundamental drivers of the weather we experience. If you begin to change that temperature gradient you will inevitably change the weather in some way. The exact mechanisms involved and how quickly they will become apparent is debatable (many already think the effects are clear, others disagree), but it's next to impossible to alter that temperature gradient without altering the weather patterns too.

Quite agree, this would be the biggest area of concern, I think and the most, at the moment anyway (until firm evidence of the other consequences are provided), that should be taken the most seriously. 

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1 minute ago, jvenge said:

Any papers on this as observed? Sea ice in the arctic has declined for some 37 years, so I imagine there is something based on observations, rather than what could happen. Your linked one doesn't load. But please just studies and papers that explain how it is happening and happened, rather than what could happen. 

Also, warmer water isn't result of the ice melting, as when there is less ice more heat is radiated to space from the north pole. Quite interesting how it works, actually. So, the issue is what makes the water warmer to then melt the ice, rather than the ice melting making the water warmer, if that makes sense?

Sorry. I'm posting this stuff from university, so the papers automatically appear for me and I'm unsure which are freely available.

Here's the link to a few observational studies (there are free versions available around, you just have to look!). However, I can assure you that the accelerated melt of permafrost cliffs is occurring - it's what I'm studying!

Modern Erosion Rates and Loss of Coastal Features and Sites, Beaufort Sea Coastline, Alaska

Annual erosion rates from 1955 to 2002 averaged 5.6 m a-1. However, mean erosion rates increased from 5.0 m a-1 in 1955–79 to 6.2 m a-1 in 1979 –2002

Increase in the rate and uniformity of coastline erosion in Arctic Alaska

Analysis of a 60 km segment of the Alaskan Beaufort Sea coast using a time-series of aerial photography revealed that mean annual erosion rates increased from 6.8 m a-1 (1955 to 1979), to 8.7 m a-1 (1979 to 2002), to 13.6 m a-1 (2002 to 2007).

Erosion and Flooding—Threats to Coastal Infrastructure in the Arctic: A Case Study from Herschel Island, Yukon Territory, Canada

Mean coastal retreat decreased from −0.6 m·a−1 to −0.5 m·a−1, for 1952–1970 and 1970–2000, respectively, and increased to −1.3 m·a−1 in the period 2000–2011.

Warmer water in summer is the result of reduced ice cover. 24 hour daylight is a great mechanism for warming the ocean surface when there's not ice and snow to reflect it. While much of that heat will get released in the Autumn, mixing will send some of it down deeper while release to the atmosphere will also cause increased surface air warming in Autumn and early winter, as we're seeing this year.

3g6vaB6.png

 

Quote

 

Wholeheartedly agree, but even as of 2016, models haven't been able to predict Greenland surface temperature from 1861 to present. It's quite unique in a way, as with a lot of tinkering the global one has seen some correlation, but Greenland remains stubborn in conforming. That said, considering what we know today wasn't able to predict the past, how can we have any confident it can reflect the future? However, I do agree that a sudden melting of the ice sheet there would cause issues. 

Re circulation and a possible shut down of the gulf stream, data from ADCP buoys indicate no observed slow down, so this slow down is actually only happening in models and in scientists hypotheses, rather than in observable evidence. 

 

When it comes to Greenland, all observational data, while variable, do show an increase in mass loss and air temperatures in recent decades. On the one hand, over the Greenland interior an increase in air temperature means the air can hold more moisture, resulting in increased snowfall. On the other hand warmer air and sea temperatures on the eats away at the ice, increases glacier flow rates and surface melting closer to the coast. I'm not too familiar with modelling attempts from 1861 to present, so if you have a few links I'd appreciate it.

Wrt the THC, the link I posted discusses the Rossby et al paper you linked to and it's limitations. The Atlantic Meridional Overturning Circulation and the Gulf Stream are not synonymous, so one aspect you have to be aware of the the positioning of the profilers/buoys and the length of their measurement times, as well as the data from other studies and locations before determining the ocean circulation changes.

 

Anywho, I must go get some work done! I'll check back later

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I'll have a good read of what you linked to and I'll dig out the info re Greenland modeling.

Re your comment about circulation changes, it is high time people started investing more in measurements and less in models, I think. Then there wouldn't be anything to doubt.  Amazingly, investment in these areas is so low when compared to the overall climate change budgets. More money is spent on flying experts to give powerpoint presentations than on measurements.

Re the one I linked, it was done over a 20 year period, which although is short, is the longest we have right now. Indeed, although not a significantly relevant time in terms of climate, you would expect to see some indicator, at least and the last several years of the measurements showed a very slight increase, rather than an expected decline.

 

 

 

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A quick update, with the single day NSIDC extent, we're now lowest on record by over 400k.
The previous latest date to hit the 7 million mark was Oct 24th in 2007 - we still haven't hit 7 million km2 this year.

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ADS extent now lowest on record by over 400k, and a remarkable 1.66 million below this time in 2014.
Also, the previous latest date the breach the 7 million km2 mark was Oct 24th in 2011 and 2012. We are still well below the 7 million mark as of the 28th.

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1 hour ago, BornFromTheVoid said:

ADS extent now lowest on record by over 400k, and a remarkable 1.66 million below this time in 2014.
Also, the previous latest date the breach the 7 million km2 mark was Oct 24th in 2011 and 2012. We are still well below the 7 million mark as of the 28th.

Those persistent +ve temp anomalies are a site to see and the +ve sea temps wont drop off anytime soon

GFS-025deg_NH-SAT1_T2_anom.png

GFS-025deg_NH-SAT2_SST.png

meanT_2016.png

GFS-025deg_NH-SAT2_SST_anom.png

Edited by stewfox
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1 hour ago, stewfox said:

Those persistent +ve temp anomalies are a site to see and the +ve sea temps wont drop off anytime soon

 

GFS-025deg_NH-SAT1_T2_anom.png

GFS-025deg_NH-SAT2_SST.png

 

Not sure about that, look how cold Siberia is and over a huge area.

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1 minute ago, 4wd said:

Not sure about that, look how cold Siberia is and over a huge area.

Siberia has large -ve abnormalities but that's all on the land. Nothing over the 'ocean' , happy to be corrected

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The Arctic Ocean as a whole looks like it is record warm for the time of year judging by the 850hPa temperatures.  There are usually widespread pools of sub -20C 850hPa air over the Arctic Ocean as we head into early November and in some years even below -25C.  This year, the sub -20C 850hPa air pools are forecast to be exclusively confined to Siberia (as Stewfox points out, over the land mass):

GFSOPNH12_72_2.png

The main culprit is the big low pressure system over north-eastern Asia which keeps pumping exceptionally warm air up from south of Alaska, right up to the North Pole.  This relented for a time over the past week, which allowed temperatures near the pole to fall very close to the long-term normal, but another lull looks unlikely for quite a while.  Over the last couple of weeks, there has also been a persistent southerly flow over the Barents/Kara Sea area, to the west of the Scandinavian blocking high.  This region will cool down a little over the coming week, but because of the anomalous warmth around the North Pole, it won't cool down anywhere near as much as we would normally expect- maybe in a week's time we'll be seeing anomalies there of around +5-10C rather than +15-20C.  The Arctic stations at Svalbard and Vize Island both look set to have a record warm October, for example see here for Svalbard's capital, Longyearbyen: https://www.yr.no/place/Norway/Svalbard/Longyearbyen/statistics.html

The warmth over the Arctic seems to be confusing the longer-range GFS and ECMWF outputs, which often have the Arctic Ocean cooling to something just slightly above the long-term normal, but always post T+168.

Looking at the model outputs in general, it looks set to be cold enough for sea ice to spread, but rather more slowly than usual, so we'll probably still be a long way below -2 standard deviations going by NSIDC as we head towards mid-November.  Growth may speed up to near normal in the Beaufort and Chukchi Seas in about five days' time due to a southerly flow bringing cold air in from continental north-eastern Canada, but ice growth will most likely remain abnormally slow to the north of Siberia with 850hPa temperatures, in stark contrast to the anomalous cold over Siberia itself, holding up at around -8C.

Edited by Thundery wintry showers
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CwVp4nUXgAQklwv.jpg

And I'll drop this in seeing as tonight is the last of the Beeb's Arctic Live progs

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They're down for maintenance stew! The gains still leave us bottom of the pile and PIOMAS appears to have us bottom of the pile as well, better not mention record low in Antarctica or record low global sea ice values lest the seesaw folk take umbridge......... (LOL) 

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Pretty incredible..

IMG_0944.JPG

Edited by Changing Skies.
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When you look at the warmth remember the humidity it also carries into the basin. That anomalous warmth means both the thickening of the ice is limited and the cold going into the ice is also limited. We saw this last years over winter and we then saw what summer did to that pack even with June/July/Aug throwing in their most ice retentive weather at the basin ( the only months with below average temps??). This Year we have a sizeable portion of all the good ice left in the basin sat over Fram / edge of the ice in Barentsz. This ice will not survive the winter so , even over winter, we lose important ice?

I was fearing 2017 melt season for a good long time, fearing it would bring us the return of the 'Perfect melt storm synoptic' but know I see that I took my eye off the ball and all those years, as autumn became warmer and winter suffered more warm intrusions, the ice was either washed out into the Atlantic or failed to grow thick and strong due to the Feb/march 'Crackopalypse' events,

Now a half decent melt season would give us an 'ice free' basin in Sept, a return of the Perfect melt storm and a pack like this summer past and we are ice free near all of Aug!!!

 

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4 hours ago, Gray-Wolf said:

When you look at the warmth remember the humidity it also carries into the basin. That anomalous warmth means both the thickening of the ice is limited and the cold going into the ice is also limited. We saw this last years over winter and we then saw what summer did to that pack even with June/July/Aug throwing in their most ice retentive weather at the basin ( the only months with below average temps??). This Year we have a sizeable portion of all the good ice left in the basin sat over Fram / edge of the ice in Barentsz. This ice will not survive the winter so , even over winter, we lose important ice?

I was fearing 2017 melt season for a good long time, fearing it would bring us the return of the 'Perfect melt storm synoptic' but know I see that I took my eye off the ball and all those years, as autumn became warmer and winter suffered more warm intrusions, the ice was either washed out into the Atlantic or failed to grow thick and strong due to the Feb/march 'Crackopalypse' events,

Now a half decent melt season would give us an 'ice free' basin in Sept, a return of the Perfect melt storm and a pack like this summer past and we are ice free near all of Aug!!!

 

Think your looking a bit too far ahead of yourself there GW but I do worry about next years melting season if these persistent warmth anamoly's continue. Supposely a negative AO helps to retain the ice in the basin but it also has some major downsides, one being temperature and secondly at least so far this freezing season, ice extent. It goes to show, ice will grow once there is some cold air and favorable winds around but if we are going to get continious winds from the south in certain parts of the basin like Barants/Kara, the ice will never grow in a million years. I do worry with these strong southerly winds coming up just how far the ice edge will towards the pole, we could be seeing another 2012 type winter here.

Do think this could be the first winter ever where Barants/Kara will remain ice free, suppose the latter has more chance if winds comes in from a very cold landmass but even so, it will not bode well for next years melt season thats for sure.

On the other hand, if we get a positive AO, then yes, the Arctic will be colder but that sort of set up tends to lead thicker ice leaving the Arctic and potentially damaging storms so are we getting to the point where unless things are calm, then no such thing as a good set up in the Arctic anymore?

 

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The Barents/Kara area was ridiculously warm in 2012 with annual temperature anomalies as high as 8C (Vize Island had a mean temperature of -6C, compared with a long-term normal of -14C) but the area cooled and iced over in late December 2012, followed by near-average temperatures during January-March 2013, so a recovery is possible. 

However, the big difference this year is that positive anomalies of 10-15C are widespread across the entire Arctic Ocean, whereas in 2012 they were largely confined to the Barents and Kara seas.  This means that a gentle influx of colder air from near the North Pole is unlikely to have as strong an effect this year, unless the pole cools down considerably over the coming month (which doesn't look likely out to at least 10 days' time).

http://ocean.dmi.dk/arctic/meant80n.uk.php

You can see from the graphs on here that temperatures in the central Arctic were generally much above normal in 2012, boosted somewhat by that exceptional Barents/Kara warm anomaly, but 2012 had alternating spells of exceptional warmth and near-average temperatures.  In contrast, 2016 has consistently been exceptionally warm, and the graph for the past 10 days shows that "10-15C anomalies across the entire Arctic Ocean" is not hyperbole.  I think there's a high chance of Svalbard remaining free of sea ice this year, and it is not implausible even into the Russian Arctic surrounding Franz Josef and Vize islands, though it's still too early in the season to be confident of the latter not freezing over.

Edited by Thundery wintry showers
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On 12/11/2016 at 23:45, Thundery wintry showers said:

You can see from the graphs on here that temperatures in the central Arctic were generally much above normal in 2012, boosted somewhat by that exceptional Barents/Kara warm anomaly, but 2012 had alternating spells of exceptional warmth and near-average temperatures.  In contrast, 2016 has consistently been exceptionally warm, and the graph for the past 10 days shows that "10-15C anomalies across the entire Arctic Ocean" is not hyperbole.  I think there's a high chance of Svalbard remaining free of sea ice this year, and it is not implausible even into the Russian Arctic surrounding Franz Josef and Vize islands, though it's still too early in the season to be confident of the latter not freezing over.

Even more warming

See 2016 cf 1980

meanT_2016.png

meanT_1980.png

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Seems quite alarming those temps charts but not surprising given the set up we have at the moment, I just wonder how far North that ice edge on the Atlantic side will head upto as Southerly winds set to dominate. As it happens, Kara sea could see some cold air as it flirts with that massive cold PV in Russia however the ice situation is going to remain very low and poor for the foreseeable future.

At least the Pacific side of the Arctic has responded with the colder conditions here and the ice is looking a little bit more like previous years now here but I suspect ice extent will remain quite low because of the lack of ice on the Atlantic side and the delay we will see in Hudson Bay getting ice covered.

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