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Powerful Cyclone to Blow Hole in Thinning Arctic Sea Ice

Back in 2012, a powerful Arctic cyclone smashed the sea ice with days of wind and waves. This year, a storm that’s nearly as strong threatens to make a similar mark on late-season melt. With a very unstable Arctic weather pattern in play, there’s an outlier possibility the dynamic is setting up for something even more dramatic by late August.

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Earlier today, a strong gale roared up out of the Laptev Sea north of central Siberia. Feeding on the abnormally warm, moist air over the Barents Sea and the hot air over northwestern Siberia, the storm collided with comparatively cold air over the central Arctic. The differences between hot/cold and damp/dry air can really bomb out a storm system.

Arctic Cyclone

(Storms, heat and moisture feed up through a high-amplitude wave in the Jet Stream over northern Europe and Siberia and into a developing Arctic cyclone over the Laptev Sea during the early hours of August 15, 2016. Image source: LANCE MODIS.)

Central pressures in the storm fell to 969 millibars and the winds whipping out over the Laptev, East Siberian, and central Arctic waters gusted at 45 to 55 miles per hour. Waves of 6 to 10 feet or higher roared through the newly-opened waters filled with increasingly dispersed ice floes.

The Great Arctic Cyclone of 2016?

This powerful storm is pulling these strong winds over some of the weakest and thinnest sections of Arctic sea ice. During July and August a huge section of ice running along the 80° North Latitude line and stretching from the Laptev, through the East Siberian Sea, and into the Beaufort Sea grew ever more thin and eventually dispersed. Now 25 to 60 percent ice concentrations in this region abound — a tongue of thinning which stretches nearly to the North Pole itself.

Powerful Arctic Cyclone

(A powerful storm running out of the Laptev Sea and into the central Arctic is threatening sea ice with strong winds, large waves, and the motion of abnormally warm surface waters. Image source: Earth Nullschool.)

The storm is generating waves, mixing warmer-than-normal surface waters with even higher temperature waters just below. These sea surfaces are between 1 and 2 degrees Celsius above average over much of the area, with pockets of 3 or even 4 C above normal surface water temperatures interspersed. The storm’s Coriolis Effect will spin chunks of ice out from the pack to float lonely in these warmer-than-normal waters as they are churned by the raging swells.

Storm Raging Over Warm Waters, Thin Ice

Currently, the storm’s strongest winds and waves are running through a big melt wedge that extends from the Laptev and East Siberian Seas toward the 85th parallel. The motion and force produced by the storm’s winds and waves will eject the ice currently located over the northern East Siberian and Chukchi Seas even as waves eat into it. Upwelling of warm water in the seas beneath the center of the storm will open and disperse the ice, generating holes and polynya as it tracks north of the 85th parallel and toward the Pole.

Thin Arctic Sea Ice

(Very low concentrations of ice, like those seen in this Uni Bremen image, are vulnerable to disruption and melting by storms during August and early September. Current ice thinning and dispersal are among the worst seen for any year. With a powerful storm now raging over the ice, impacts to end-season totals could be significant. Image source: Universität Bremen.)

Compared to the Great Arctic Cyclone (GAC) of 2012 — an event that helped to tip that year into the strongest late-season melt on record — this storm is a bit weaker. The GAC bottomed out at 963 mb and carried on for about four days. The current storm, by comparison, is expected to remain in place for quite some time even as it slowly weakens over the coming days.

Arctic sea-ice extent values are now tracking at around third lowest on record, or just above the 2007 line. Such a strong storm certainly has the potential to knock a big hole in the ice, possibly propelling 2016 closer to 2007 ranges or even beyond them. Surface waters in the Laptev, East Siberian, Chukchi, and Beaufort Seas aren’t quite as warm as they were in 2012, but there’s still a lot of potential here for storm-associated melt. Meanwhile, the very warm waters over the Kara and Barents Seas remain a disturbing feature.

Arctic in hot water

(Above-average sea-surface temperatures during late summer have more potential to rapidly melt sea ice when they are churned up and put into motion by powerful storms. Image source: NOAA NCEP.)

Models predict that lows will continue to feed in from the Atlantic and northeastern Siberia along various high-amplitude waves in the Jet Stream to combine in a triangular bite between the East Siberian Sea, the Laptev Sea and the Pole. Such continued reinvigoration will tend to enforce a generally stormy and unstable atmosphere. And there’s some risk (small, but worth considering) that the current storm could refire into something more powerful on the fuel provided by one of these lows.

Troubling Atmospheric Instability Loads the Dice for Future Bombification

Already, a few of the long-range models are popping with amazing predictions of storm-center intensity in the range of 950 to 960 mb. Both the GFS model and CMC models separately produced these results for the nine to 12 day timeframe. GFS had backed off its own high-intensity forecast when this odd CMC run popped up (see below).

CMC Arctic Megacyclone

(CMC 10-day forecast model run showing an extremely powerful 955-mb low just north of Svalbard on August 25th. Such a storm is low-probability at this time, but its formation would likely result in serious impacts to sea ice. Image source: Tropical Tidbits.)

Though these are long-range outliers, there is quite a lot of fuel for strong storms in the region this year due to conditions related to human-caused climate change. In particular, ocean surfaces in the Barents and Kara Seas are in record-hot ranges. And the heat and moisture coming off those waters is fuel for some serious atmospheric instability as the Polar region attempts to cool. Any significant cooling in the 80-90° North Latitude region would help to generate a strong dipole between this zone and the Kara-Barents. Such a dipole would create strong instability for storm generation.

A low bombing out at 953 to 955 mb in ten days, as the CMC model currently indicates, would represent an Arctic megacyclone with serious potential to wreck sea ice. The location predicted would generate a strong push of warm water from the Barents and Laptev and on toward the ice-clogged polar waters. The resulting Ekman pumping and powerful swell generation would have the potential to generate severe ice losses in the late August timeframe.

Probabilities for such a storm this far out are low, but given the underlying conditions, it’s worth putting a marker out. This is, therefore, a situation to watch. We’ve already got one strong storm blowing away at the ice. A one-two punch would hurt even more. In other words, the situation in the Arctic just got really interesting. Let’s just hope it doesn’t tilt into scary…

Links:

Big Cyclone

LANCE MODIS

Earth Nullschool

Universität Bremen

Ice vs. Storm

NOAA NCEP

Tropical Tidbits

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Smokey Arctic Cyclone Sets Sights on Central Arctic; PIOMAS Shows Sea Ice Volume 4th Lowest on Record

Smokey Arctic Cyclone on August 6, 2013

Smokey Arctic Cyclone on August 6, 2013

(Image source: NASA/Lance-Modis)

A strong, 980 mb cyclone formed over the Laptev Sea today, pulling in a dense coil of smoke from Siberian wildfires raging to the south and setting its sights along a path that will bring it through waters filled with a slurry of broken ice, passing over the North Pole, and then heading on toward the Fram Strait.

Unlike the Sudden Arctic Cyclone of late July, the new Smokey Arctic Cyclone is strengthening over a region of open water in the Laptev Sea before it begins its passage over a broken ice pack. This will allow the storm to develop more fetch and wave action before it encounters the sea ice. Though not as strong as the Great Arctic Cyclone of 2012, this Smokey storm is likely to pack 25-40 mph winds over large expanses of water and ice, applying wave action to a greatly diffuse and weakened film of thin ice. Though Ekman pumping and mixing of cold surface layers with deeper, warmer layers will likely have some impact on ice — thinning and dispersing it further — it remains to be seen if this storm will be strong enough to have a decisive influence on final melt for the 2013 season.

The storm is, however, moving through an area of very weakened ice even as it pulls a flood of warmer, rougher water along with it. And it remains to be seen what, if any impact, soot pulled in from the Siberian wildfires will have on the ice. Solar insolation is steadily falling as we move on into August. That said, the angle of the sun is still high enough to have some added impact should soot-laden precipitation fall.

The ice state, which has seemed weak and diffuse all summer appears especially vulnerable now.

Smokey Cyclone Broken Ice

(Image source: NASA/Lance-Modis)

Cracks and large sections of open water riddle the thin ice in a wide stretch from the Chukchi Sea, running through a portion of the Beaufort and then turning on toward the open water in the Laptev. So it will be interesting to see how much this storm affects this section of ice. As the storm is predicted to move on through the Central Arctic and then spend a day or two churning near the Fram Strait, it may also give the thick ice a bit of a late-season nudge.

Party like it’s 2009?

Overall, the storm would have to be a very extreme event to drive the current melt rate to near 2012 levels. Both sea ice extent and area are currently tracking near 2008 and 2009 while sea ice volume, as of mid-July, was just a hair above the third lowest year — 2010. Though it is still possible, given the sea ice’s very fragile state, that 2013 could still hit record lows this year, the likelihood, with each passing day, grows more remote.

PIOMAS Mid-July 2013

PIOMAS Mid-July 2013

(Image source: PIOMAS)

So, at this point, it is worth considering that 2013 may be a counter-trend year. Most of the record heat and warmth associated with human caused warming has been confined to a region of the high Arctic land masses between 55 and 70 degrees north. In this zone, we’ve seen an ominously large number of heatwaves, where temperatures exceeded 90 degrees, along with wildfires spreading above the 60 degrees north latitude line. And though large areas of warmer than normal surface water temperatures invaded the sea ice, air temperatures have been at or slightly lower than average. This is a result of persistent cloudy conditions dominating during periods when solar insolation would have done its greatest damage to the ice sheet. Storms, which at times seemed to drive more rapid melt had the added effect of spreading out the ice, likely contributing to cooler air temperatures. These storms were not powerful enough to provide the energy needed to push 2013 into record melt territory. It is also possible that fresh water melt from the Greenland ice sheets — representing a large pulse of about 700 cubic kilometers last year — and from record or near-record snow melts on the continents surrounding the Arctic added some resiliency to the greatly thinned ice in the Beaufort.

These various conditions may be consistent with a combination of natural variability and a potentially emerging negative feedback from melting snow and ice. If 2013 does emerge as a counter trend year, though, it is no indication, as yet, that Arctic melt, overall, has slowed. 2012 was a powerful record melt year and one that occurred under far less than ideal conditions. It is just as likely that natural variability and human forcings will swing back in the other direction come 2014, 2015 or later as happened through the period of 2008 through 2012.

All that said, it is still a bit premature to call the 2013 melt season. We have a storm laden with smoke from the immense Siberia fires on the way and large regions of sea ice remain very fragile. As ever, the Arctic is reluctant to give up her secrets, especially under the assaults of human warming.

Smokey Storm 980 MB

Smokey 980 mb Cyclone churns through the Laptev

(Image source: DMI)

Links:

The Arctic Ice Blog

NSIDC

First Named Arctic Cyclone to Deliver Powerful Blow to Sea Ice?

The weather models are all in agreement, an Arctic Cyclone is predicted to form over the Beaufort and Chukchi Seas tonight and tomorrow, then strengthen to around 980 millibars as it churns through a section of thin and broken sea ice. The storm is predicted to last at least until Saturday and is expected to deliver gale force winds over a broad swath of thinning sea ice throughout much of its duration.

Arctic.wind.60.cc23

Gale force winds predicted for Beaufort, Chukchi and East Siberia Seas.

(Image source: Arctic Weather Maps)

The fact that this particular storm is forming in late summer is some cause for concern. The sea ice has been subjected to above freezing temperatures for some time. Melt ponds have increasingly formed over much of the Arctic and, since late June, most of the precipitation falling on the Arctic has been in the form of rain. The central ice pack is in complete chaos, with extensive thinning and fracturing surrounding a wide arc near the North Pole and a broad melt triangle full of broken ice and patches of open water extending far into the Laptev Sea. Further, the long duration of sunlight falling on the ice surface and penetrating into the ocean layer just beneath has likely warmed waters below the cold, fresh layer near the ice.

As the storm passes, its strong winds and cyclonic circulation have the potential to dredge up this warmer water and bring it in contact with the ice bottom. Such action can rapidly enhance melt, as we saw during the Great Arctic Cyclone of 2012. Since the brine channels are all mostly activated (with much ice in the region now above -5 degrees Celsius) Cyclonic pumping during storm events like this one can transport sea water directly through the ice to increase the size of melt ponds, to break, or to even disintegrate ice flows.

It is important to add the caveat that this particular storm in not predicted to be quite as long or as strong as the Great Arctic Cyclone of 2012 which, in its first week, coincided with a loss of 800,000 square kilometers of ice. But Arctic weather is nothing if not unpredictable and this particular event could just as easily fizzle as turn into an unprecedented monster.

That said, a number of concerning conditions have emerged just prior to this storm that may result in an enhanced effect on the ice. The first condition is that large sections of the Beaufort, East Siberian and Chukchi Seas are covered in thin, diffuse and mobile sea ice. These conditions are clearly visible in the surface shots provided by NASA/Lance-Modis:

Ice and Open Water North of Wrangel Island

In this section, as in other broad stretches of the Beaufort, the ice is reduced to a kind of slurry in which, as Neven over at the Arctic Ice Blog notes, the individual flows are completely degraded and difficult to make out. This slushy region is in direct contact with a region of mostly open water. Such areas of de-differentiated ice are likely to show greater mobility and enhanced wave action during storms, which puts them at risk of more rapid melt.

Another somewhat ominous note in advance of this storm is a rise in Arctic Ocean temperature anomalies over the past couple of days. NOAA’s surface temperature measure indicates a spreading pool of warmer than normal surface ocean conditions throughout the Arctic. In the region this storm is predicted to most greatly affect, the storm will have the potential to bring such warmer than normal surface waters into more consistent contact with the ice through the mechanical action of waves and by activating the brine channels in the ice. Further, a large pool of much warmer than normal surface water in the Chukchi Sea is likely to be driven deeper into the ice pack where it also may enhance melt.

sst.daily.anomCyclone

(Image source: NOAA)

In general, there’s quite a bit of atmospheric and ocean heat energy for this storm to tap and fling about. Not only is the surface ocean warmer than 1971-2000 base temperatures, but most continental land masses surrounding the Arctic are showing highs between the mid 60s to upper 80s and lows between the 40s and upper 60s.

ECMWF model forecasts show the storm tapping some of this energy in advance of intensification, with a tongue of warm Alaskan and Canadian air being drawn into the storm at the 5,000 foot level late Monday and early Tuesday. Directly opposite, Siberia and Eastern Europe have hosted very warm air masses with daytime surface temperatures above the Arctic Circle reaching the upper 80s consistently over the past week. This warmth also encroaches just prior to storm intensification.

ECMWF warm air advance

(Image source: ECMWF)

Added heat energy injected at the surface and at the upper levels will ensure that the vast majority of precipitation during this event emerges as rainfall.

Broader effects of this storm could be quite significant. The US Navy’s CICE models are showing a greatly enhanced ice motion throughout the duration of this storm as its counter-clockwise circulation is predicted to dramatically increase the movement of the Arctic’s remaining thick ice toward the Fram Strait. The Navy’s thickness monitor also shows a jump in ice thinning and dispersal throughout the ice pack over the duration of this event. In particular, the back end of remaining thick ice north of the Canadian Arctic Archipelago is mashed like a tube of tooth paste in the model run, pushing a broad head of ice toward the Fram. At the same time, a large section of Central ice, earlier thinned by PAC 2013, is projected to rapidly expand and further thin under the influence of this storm.

Note the rapidly expanding melt wave from the North Pole to the Laptev that appears in the final frames of the run below:

 

Arctic Cyclone Daly

(Image source: US Navy)

So it appears we have a short duration but relatively high intensity Warm Storm event predicted to have broad-ranging effects from the Beaufort to the Central Arctic. An event that could have impacts similar to those of the Great Arctic Cyclone of 2012. Should such circumstances arise, it begs the question — is the Beaufort a region that is more likely to spawn these kinds of storms come late July through early to mid August? The region is now surrounded by increasingly warm continents. The observed weakening of the polar Jet Stream by 14% has resulted in a much greater transport of heat to the high continental boundary, as evidenced by a broad swath of heat-waves ringing the Arctic above the 60 degree North Latitude line. The increasingly thin Beaufort ice jutting out into this crescent of continental heat may well be the ignition point for major atmospheric instability, powerful storms and related heat transfer. Something to consider should these kinds of late season ice melters recur on a more frequent basis.

To this point, a new naming convention has been proposed over at the Arctic Sea Ice blog for summer storms that greatly impact the ice. Preliminary standards have been set for storms with a central pressure lower than 985 mb (at peak intensity) and a duration longer than 4 days. Suggestions for storm titles include traditional Inupiat names from this region or even the use of the names of prominent climate change deniers (My opinion is that both calling attention to major Arctic melt events and how climate change deniers have attempted to cover such events up would be an excellent use of such a convention, but I may be out-voted).

You can take part in the naming convention discussion on the Arctic Ice Blog by following this link here.

In conclusion, the potential arises for the first named Arctic Cyclone to result in dramatic melt and weakening of sea ice throughout the upcoming week. This potential heightens the risk for 2013 to be another record melt year and so we will continue monitoring the storm’s development closely for you.

 

 

 

410,000 Square Kilometers of Sea Ice Lost in Two Days: Persistent Arctic Cyclone Weakens Heart of Ice, Rapid Edge Melt Devours Fringe

According to Cryosphere Today, Saturday’s Arctic sea ice area measured 10.22 million square kilometers. By Monday, that number had dramatically fallen to 9.81 million square kilometers. This loss of 410,000 square kilometers over the course of two days is extraordinarily rapid, even for a time of year when melt has tended to accelerate. On sea ice area graphs, it makes the last few days look like area numbers fell off the edge of a cliff. (Note that Cryosphere Today area numbers usually lag by a few days. So what we’re actually seeing is area measurements through Friday, June 7th).

Up until recently, sea ice area melt had been relatively moderate. But now, after a week of consistent 100,000+ square kilometer daily losses, and two days of 200,000+ losses, sea ice area is only a smidge above that of record melt year 2012 on the same day in June. In total, more than 800,000 square kilometers were lost over the course of the past week. This melt rate, if sustained, would render the Arctic ice-free by late August. If we look at past records, it is not likely that these rates of loss will continue. But past records may not prove a good guide in the current age of fragile Arctic ice. It is quite possible, given the ice’s fractured, frail, and mobile state, that such enormous melt rates, in the worst case, could be sustained or even exceeded. In this event, we would witness a total collapse of Arctic sea ice by the end of this year. So should current dramatic melt rates be sustained or worsen, we may be upping our forecast chances for near total melt by end 2013 (still at 10%).

In any case, warnings that we were not out of the woods after a slower than expected melt during May, seem to have born out in spades.

Persistent Arctic Cyclone + Rapid Edge Melt = Brutal Combination

The twin forces driving this sea ice loss are the Persistent Arctic Cyclone of 2013 (PAC 2013 — I’ve decided to keep this name. Neven has sanctioned it, even as he playfully recommended calling it Rocky Balboa, which would be entirely appropriate for this dogged storm.), which we began warning about on May 30th in The Big Thin Begins, and a rapid edge melt that also began in early June.

PAC 2013 has, for more than two weeks, been invoking a number of forces detrimental to sea ice in the Central Arctic. It has pulled warmer water up in a column beneath it, melting the bottom ice. It has, through cyclonic action, dispersed the ice away from its center of circulation. And, via energetic storm winds, it has churned and disturbed the surface waters just beneath the ice or at the surface, creating a mixing action that also erodes the ice.

Together, these forces have dramatically reduced the Central Arctic Sea ice. Sea ice thickness, according to the US Navy, after already thinning somewhat, looked like this on May 30th:

CICE2013

Today’s most recent measure shows the central ice pack suffering substantial reduction since that time:

arcticictnnowcastJune9

Note the major thinning in a region of the thickest ice even as thinner regions closer to Siberia ablated further over the past ten days.

Cracks visible in the Lance-Modis satellite shots confirm an increased breaking of the sea ice even just north of the Canadian Arctic Archipelago, where the ice is thickest. Through a combination of bottom melt and sea ice dispersal, it appears that a broad region of this ‘most resilient’ ice lost between .5 and 1 meter worth of sea ice over the past ten days. By June 6th, these losses began to show up in the, less sensitive, Cryopshere Today concentration graphic. By June 8th, a large swath where sea ice concentration had dropped to between 60 and 70 percent was indicated in the region most affected by PAC 2013:

CTconcentrationJun8

(Image source: Cryosphere Today)

Note the large swatch of red running directly through the Central Arctic. That’s a broad region of ice thinned by our Persistent Arctic Cyclone showing up in the Cryosphere Today measure.

Today, the cyclone has shifted toward the Laptev Sea and is dramatically churning the thinner ice there, shifting its special brand of havoc closer to the Siberian coastline. We’ll discuss more about this new development in an upcoming PAC 2013 forecast.

As PAC 2013 churned through the Central Arctic, melt accelerated at the ice periphery. In the Canadian Archipelago, large regions of ice turned a characteristic shade of blue as melt lakes developed and insolation began to do its work there. Both Hudson Bay and Baffin Bay also saw dramatically increased rates of melt. This larger region of the Canadian Arctic saw a powerful influx of higher temperatures. A pulse of warmth that likely pushed melt faster. Temperatures of 10-20 degrees Celsius became a common event near Hudson Bay and southern portions of the Canadian Archipelago. Above freezing temperatures stretched far northward, driving deep into the Beaufort Sea.

Across the Arctic Ocean, the Laptev Sea began to melt at a faster pace even as a region of the Chukchi Sea displayed a dramatic and rapid disintegration of sea ice. You can see this rapid melt by comparing the Lance-Modis image from June 2nd to today’s Lance-Modis shot of the region:

Bering Melt Start

This is what Chukchi Sea ice looked like on the 2nd of June (Image source Lance-Modis).

Bering Melt End

And here is what it looks like today (Image source: Lance-Modis)

Note the clearing of most ice from the Bering Straight even as the ice edge retreated northward toward an increasingly fractured and thinned polar ice cap. As warmer air is expected to enter the Chukchi over coming days, it appears that conditions will continue to favor rapid edge melt there.

Weather model forecasts also show warm air flooding into many regions at the ice edge, growing especially prominent in the Beaufort, Chukchi, and East Siberian Seas. Meanwhile, PAC 2013 is expected to continue to churn through the Central Arctic. These conditions are now projected to persist until at least June 20th, at which point our Persistent Arctic Cyclone will have lasted nearly a month.

As noted above, this combination of conditions: warm air invasion at the ice edge, historically thin, fragile, and mobile sea ice, and a Persistent Arctic Cyclone (PAC 2013) are likely to continue to promote rapid to very rapid melt in the Arctic as June continues to advance. Though 200,000 kilometer per day sea ice area loss is extraordinarily rapid and dramatic, the potential exists for single day losses to exceed even this highly radical number. A sea ice cliff for June 2013, thus, appears to be a distinct potential.

Links:

US Navy

Cryosphere Today

The Arctic Ice Blog

Lance-Modis

 

Storm Thins Sea Ice: Most Sea Ice Monitors Now Show 2013’s Persistent Arctic Storm’s Dramatic Impact

Over the past two weeks a storm has raged through the Arctic, churning and thinning the region’s thickest, most resilient sea ice. Now, almost all major measures show a dramatic thinning of the central ice even as warmer air has been funneling into the region. Models still show storm conditions continuing until June 17th. So the ongoing thinning and churning this storm has produced is likely to continue even as the region steadily warms.

Name Change to Persistent Arctic Storm 2013

The storm that has now plagued the Arctic for two weeks has recently involved numerous low pressure areas. For this reason, it is appropriate to change its name, since multiple low pressure systems, rather than a single consistent cyclone, are involved. So, going forward, we will be calling this event: Persistent Arctic Storm 2013 (PAS 2013).

Pressure Levels Rise Somewhat

Today, we can see a double barrel low pressure system still hovering over the central Arctic:

PAS2013pressureJune7

(Image source: DMI)

Pressure levels are up somewhat, now showing about 995 mb in two low pressure centers flanking the North Pole. Forecast models show the storm remaining in the 985-995 strength range all the way out to June 17. These models have tended to show the storm hovering closer to Svalbard, the Kara and Laptev seas over this period as warmer air filters in and builds over the region of the Beaufort Sea and East Siberian Arctic Shelf. These models can be subject to quite a bit of change, so we’ll have to keep a close eye for any alterations.

Tomorrow’s forecast is for the double-barrel low to recombine over the North Pole and drop to 985 millibars. It’s important to note that 985-995 is still a moderately strong storm. By comparison, Tropical Cyclone Andrea bottomed out at 997 millibars before dumping 10 inches of rain and sending 2-5 foot storm surges over portions of coastal Florida. So this particular storm, with a strength ranging from 975 to 995 millibars over much of its life contains a substantial amount of energy. It is also worth noting that quite a bit of warm air is lurking around the storm’s periphery. This air could boost the storm if conditions favor an influx of warm, moist air.

Dramatic, Widespread Thinning Now Visible in Most Sea Ice Monitors

It’s becoming more and more clear that this storm’s energy has gone to work in significantly eroding the Arctic’s central ice. Now, almost all sea ice monitors are showing dramatic impacts on sea ice in and around the Central Arctic Basin.

arcticictnnowcastPAS

(Image source: US Navy)

The US Navy’s CICE/HYCOM thickness model now shows substantial thinning and divergence in two regions of the central, thick ice. The region closer to the Russian side of the Arctic has persisted for about a week now and is confirmed in the other measures below. The second region, closer to the Canadian Arctic Archipelago is newer. So we’ll have to look for persistence there. Overall, the remaining thick ice is in a much worse state in this monitor than it was last week.

UNIBREMENPAS

(Image source: Uni-Bremen)

Uni-Bremen has also shown persistent and growing thinning in its surface ice concentration monitor. Now, many regions where the storm passed are showing surface concentrations of 75% or less. These features have continued to grow more prominent as ice in the Central Arctic thinned over the past week. In contrast to the US Navy’s CICE/HYCOM thickness model, this Uni-Bremen model measures surface concentration while CICE models thickness.

Loss of surface concentration is the final result of thinning. But thinning tends to occur before losses in surface concentration are visible.

Arctic_r04c04.2013158.terra.1kmPAS

(Image source: Lance Modis)

A few breaks in the clouds have also opened up over the Central Arctic. These gaps confirm what both Uni-Bremen and CICE are showing. In the most recent Lance-Modis shot, we have visual of a dramatic Central Arctic thinning. In the upper left hand corner, note the large region of thinned and broken ice. This visual shot shows that the thinning and loss of concentration seen in the other measures bears out in reality. (So yes, Neven, it increasingly appears that this is quite real.)

Together, these measures provide growing evidence that the central Arctic sea ice has taken a substantial blow.

More rapid decline in sea ice area and extent during storm

As the central ice thinned and dispersed during this month’s Persistent Arctic Storm, sea ice area and extent also rapidly dropped off. Both Cryosphere Today and JAXA showed area and extent falling at rapid rates over the past week. Weekly extent declines for JAXA is in the range of 400,000 square kilometers, dropping back to 2012’s lower levels. Cryosphere Today sea ice area losses were also rapid — in the range of 500,000 square kilometers. But sea ice area, according to Cryosphere Today, remained above 2012 levels.

Sea_Ice_ExtentPAS

(Image source: JAXA)

Some had asserted that this storm would result in ice formation, not loss. But visual, concentration, and thickness monitors show that just the opposite occurred. Furthermore, increasing (not slowing) pace of sea ice loss in both area and extent measures confirm the likelihood that this Arctic storm hastened sea ice erosion, melt, and volume loss during early June.

This Storm’s Story Isn’t Over Yet

Needless to say, this storm’s story isn’t finished yet.

Associated with its circulation was the influx of above-freezing temperatures into the Central Arctic. You can see this area  in the DMI temperature measurement below:

temp_latestPAS.big

(Image source: DMI)

Note the swath above freezing temperatures hovering near the region of East Siberia. This area is a remnant of warm air pulled up from the Scandinavian heatwave earlier this week. It has now transitioned to its new location where models expect above-freezing temperatures to amplify over the coming days.

By Wednesday of next week, model runs show a large influx of above freezing average temperatures expanding over this half of the Arctic Basin, while a still respectable 990 millibar Persistent Arctic Storm continues to chew away the sea ice on the Svalbard side of the North Pole. Storm rotation is also shown to pull in 5+ degree Celsius temperatures into the region of the Kara and Laptev seas. By June 17, the model looks like this:

Arctic Forecast Persistent Storm Impacts

(Image source: ECMWF)

Our storm still persists, centering now over Svalbard and the Kara Sea, while warm air is shown to engulf and invade the Arctic .

So it appears that from all sides warmer air continues to encroach and get wrapped into this storm. Such conditions are likely to further enhance rapid melt and thinning of the sea ice. Should these conditions, as projected in the ECMWF models, bear out, it is likely we will continue to see a melt acceleration over the next ten days. The higher temperatures, the action of the persistent storm in the central Arctic, and the already observed thinning of sea ice there are indications that melt may well already be on its way to a rapid ramp up.

Conditions remain very dynamic and unstable with the likelihood of dramatic melt increasing as time moves forward.

Links:

The Arctic Ice Blog

DMI

US Navy

Uni-Bremen

JAXA

Cryosphere Today

Lance Modis

ECMWF

Models Show 975 Mb Low Forming in Arctic by April 13. Could This Potential Cyclone Enhance Early Season Melt?

April13ECMF

(Image source: ECMWF)

It’s a long way out, but current weather model forecasts show a strong storm forming over central Russia and moving north into the Arctic Ocean by mid-April. Models show a major storm tearing up through Russia, gaining strength as it comes to the sea ice edge on April 13th.

The storm drops down to around 975 mb by this time, a pressure comparable to a weak to moderate strength hurricane. However, the effects of such a system would be spread over a broader area, so peak wind speeds probably wouldn’t approach that of a comparable tropical system.

Nonethelss, such a storm has the potential to drive strong winds into the region, possibly disrupting an area of historically thin sea ice. The back side of the storm also digs deep into the mid-latitudes, pulling up warmer air from the south. Such processes could enhance early season sea ice melt and breakage, especially given the demonstrated fragility of sea ice during both the summer of 2012 and the winter of 2013.

There isn’t too much precedent for strong storms disrupting spring ice so early in the year. But the Great Arctic Cyclone of the summer of 2012 and brisk winds offshore setting off a major sea ice cracking event from February to March of 2013 provide evidence of the severely fragile state of Arctic sea ice. So it can’t be entirely ruled out that a strong storm system such as the one predicted could have a major impact.

The date, April 13, is still a long way off. But if the storm emerges as predicted, we may see yet one more major Arctic ice event in the coming weeks. One with the potential to accelerate early season melt and break-up. Definitely something to keep a watchful eye on.

140,000 Square Kilometers of Sea Ice Lost in One Day; With One Month of Melt Remaining, Arctic Very Close to New Record Low

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According to reports from the Polar Research Group at the University of Illinois, sea ice area diminished by 140,000 square kilometers since the last reading taken yesterday. This very large single day drop has punctuated the end of an already strong melt since August 2nd. Over that time, 580,000 square kilometers of Arctic sea ice has melted. This equals a rate of more than 80,000 square kilometers each day (latest values are for August 9th).

Currently, 3,203,000 square miles remain of Arctic Sea Ice. This is within close striking distance of the record low set for 2007 at slightly more than 2,900,000 square kilometers. At the current average rate of melt, this record will be breached within 4 days.

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A strong Arctic cyclone, whose remnants can be seen in the above graphic, churned through the region over this past week. The low is slowly degrading, but may still be providing energy, wave action, and moist air that could be enhancing sea ice melt. Most researchers have noted that the storm probably increased the rate of ice melt. And we have seen increased melt in the regions the storm impacted.

A satellite image of the storm taken earlier this week has been provided by NASA:

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If you look closely, you should be able to pick out the swirl of white clouds over the ice sheet.

So far, early August sea ice melt has been very rapid. Already, current values place sea ice area between the fourth and fifth lowest levels ever recorded. As noted above, if melt continues at the current rate, we are just days away from reaching the record lows set for 2007. But given the weather event that is now fading, it is possible that rates of melt will be a bit milder in coming days. Needless to say, we are still very close to a new record with more than a month of melt left.

UPDATE:

NSIDC is now showing that a large area of sea ice has now separated from the main flow. Detachment of this kind is another sign that sea ice have become vulnerable to the affects of storms and strong winds in the Arctic. In this case, this sea ice was stranded and separated from the main sheet by strong storm winds associated with the recent Arctic Cyclone. You can see the detached section in the image provided by NSIDC:

Now all the major sea ice monitoring sites are showing this detachment.

NSIDC is also showing a very large drop in sea ice extent. This roughly tracks with the large drop in sea ice area observed by the Polar Research Group. Here is the most recent sea ice extent graph from NSIDC:

Note the drop in extent after the recent Arctic cyclone.

Please help support our continuing efforts.

Please help support our continuing efforts.

Links:

http://nsidc.org/arcticseaicenews/

http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=78808

http://arctic.atmos.uiuc.edu/cryosphere/

http://ocean.dmi.dk/arctic/weather/arcticweather.uk.php

http://www.ijis.iarc.uaf.edu/cgi-bin/seaice-monitor.cgi

Arctic Cyclone Slowly Fading, Leaves Greatly Reduced Sea Ice in Its Wake

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A powerful Arctic cyclone that played havoc with sea ice is now slowly fading.

Since August 5th, the storm has raged over the Arctic, enhancing melt and stranding a large ice flow in the East Siberian Sea. Taking a look at Japanese Space Agency images of the ice sheet, it is easy to see the storm’s impacts from these before and after shots:

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The above image was taken by JAXA on August 4th. In the image, you can see an area of thin ice in the Arctic Ocean between Alaska and Siberia. In the next image, taken today, much of that sea ice is gone:

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In addition, it appears that a rift has opened between the main ice flow surrounding the North Pole and a rapidly diminishing flow closer to Siberia and Alaska. In general, both the storm and other strong summer melt conditions have pushed the ice pack into record melt territory for sea ice area and extent for this time of year.

Since we began making daily observations on Arctic sea ice decline on August 2nd, sea ice area has fallen by about 440,000 square kilometers or more than 70,000 square kilometers per day. Current total area measurements from the Cryosphere Today website show 3,340,000 square kilometers, about 400,000 square kilometers above the record low set for 2007. Needless to say, if ice melt rates continue apace, it would take less than six days to break the 2007 record low for sea ice area.

Sea ice extent also continued to show declines with both NSIDC and JAXA widening the gap between current measurements and the 2007 record low set for this date.

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If weather conditions continue to remain favorable for Arctic melting, it appears likely that new records may be reached for both extent and area. And, as mentioned in the previous post, sea ice is also tracking for a new record low volume in 2012 as well.

As the NSIDC noted in its report yesterday — this has been an interesting summer. And it appears likely to get more interesting before it’s over.

Please help support our continuing efforts.

Please help support our continuing efforts.

Links:

http://www.ijis.iarc.uaf.edu/cgi-bin/seaice-monitor.cgi

http://nsidc.org/arcticseaicenews/

http://arctic.atmos.uiuc.edu/cryosphere/

http://ocean.dmi.dk/arctic/weather/arcticweather.uk.php

https://robertscribbler.wordpress.com/2012/08/08/arctic-cyclone-hangs-on-record-2012-sea-ice-loss-continues-large-areas-of-sea-ice-detacted-from-main-ice-flow/

Arctic Cyclone Hangs On, Record 2012 Sea Ice Loss Continues, Large Areas of Sea Ice Detached From Main Ice Flow

(Weather Report Credit: DMI)

An immense cyclone that has ravaged the Arctic continues its powerful blow today.

The cyclone, which formed over East Siberian and then ripped through the Arctic has left a wave of chaos in its wake. First, it pushed 10-12 foot seas through a region that rarely sees powerful storms of this type. Then, it enhanced sea ice melt in the regions it impacted. Now, it hangs on as a 970 millibar storm system — a pressure level usually seen in tropical cyclones.

It is difficult to emphasize how rare this event is. Though summer cyclones do occur, most tend to be weak and have little effect. Usually, the strongest events occur during winter time. The last powerful summer Arctic cyclone was observed in 2006, but this 2012 event is much more powerful. If these strong summer storm events become more common-place, they are likely to represent another threat to Arctic sea ice.

As the storm continued, so has rapid melt. Since August 3rd, more than 360,000 square kilometers of sea ice has been lost — an average rate of more than 70,000 square kilometers each day. Currently, Cryosphere Today is showing a total sea ice area of 3,425,000 square kilometers, a mere 450,000 square kilometers above the record low set in 2007, with more than one month of melt left in this season. For this date, Cryosphere Today is showing sea ice area levels more than 430,000 square kilometers below the previous record low set just last year.

Furthermore, something entirely unprecedented is happening to the ice sheet. Driven by storm winds, it appears that a large section of sea ice has detached from the main flow and is now stranded in the East Siberian Sea. This is an event that is without precedent in the satellite record.

Detachment

For years, Arctic researchers have speculated that weakened Arctic sea ice would be vulnerable to detachment from major storm or wind events. Now that speculation is reality. A large area of ice is now detached from the main flow and, due to that detachment, remains vulnerable to enhanced melting around its edges and at its center. In particular, this detachment shows that Arctic sea ice has become even more vulnerable to rapid melt due to another powerful feedback mechanism acting on it.

It is difficult to emphasize how important an event this is. In short, it is another powerful and glaring sign that Arctic Sea ice may be in terminal decline.

Sea ice extent measurements also continue to show rapid melt with both the Japanese Space Agency (JAXA) and the NSIDC showing current day melt below the record lows set for this date:

Please help support our continuing efforts.

Please help support our continuing efforts.

 

Links:

http://arctic.atmos.uiuc.edu/cryosphere/

http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

http://nsidc.org/arcticseaicenews/

http://neven1.typepad.com/blog/2012/08/arctic-storm-part-3-detachment.html#more

https://robertscribbler.wordpress.com/2012/08/07/powerful-arctic-cyclone-driving-record-sea-ice-melt/

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