What's new in the Arctic ?

[Glen Koehler]

The end-game begins through the Nares Strait?

"Ice arches holding Arctic's 'last ice area' in place are at risk, researcher says"
https://phys.org/news/2021-01-ice-arches-arctic-area.html

Excerpts  -------
But recent research at the University of Toronto Mississauga suggests the last ice area may be in more peril than previously thought. In a recent paper published in the journal Nature Communications, Professor Kent Moore and his co-authors describe how this multi-year ice is at risk not just of melting in place, but of floating southward into warmer regions. This, in turn, would create an "ice deficit" and hasten the disappearance of the last ice area.

"The last ice area is losing ice mass at twice the rate of the entire Arctic," Moore says. "We realized this area may not be as stable as people think."

His most recent analysis of satellite data says the problem may be getting even worse. The arches along Nares Strait that historically have held the Last ice Area in place have become less stable, according to the study.

"The ice arches that usually develop at the northern and southern ends of Nares Strait play an important role in modulating the export of Arctic Ocean multi-year sea ice," he and his authors write.

Ice arches only form for part of the year. When they break up in the spring, ice moves more freely down the Nares Strait. And that breakup is happening sooner than in the past.

"Every year, the reduction in duration is about one week," (emphasis added by GK) Moore says. "They used to persist for about 200 days and now they're persisting for about 150 days. There's quite a remarkable reduction.

"We think that it's related to the fact the ice is just thinner and thinner ice is less stable."

More information: G. W. K. Moore et al. Anomalous collapses of Nares Strait ice arches leads to enhanced export of Arctic sea ice, Nature Communications (2021). DOI: 10.1038/s41467-020-20314-w

[Glen Koehler]

From:
Slater, T., Lawrence, I. R., Otosaka, I. N., Shepherd, A., Gourmelen, N., Jakob, L., Tepes, P., Gilbert, L., and Nienow, P.: Review article: Earth's ice imbalance, The Cryosphere, 15, 233–246, https://doi.org/10.5194/tc-15-233-2021, 2021.
https://tc.copernicus.org/articles/15/233/2021/tc-15-233-2021.pdf 

     "While the progressive retreat of Arctic sea ice has been driven by radiative forcing, this has been mediated in part by the increasing presence of open water (Perovich and Richter-Menge, 2009), and broader changes in oceanic conditions are expected to play an increasingly important role (Carmack et al., 2016)"

     But the at the end of the article they say this:  "Attributing Arctic sea ice decline and ice shelf calving to increased radiative forcing,..."
      I understand that they do this as a shortcut in a calculation of what portion of global glacier/ice sheet/sea ice loss is due to atmospheric vs. ocean warming.  But that seems like a pretty crude shortcut.  My understanding is that ocean warming is already a contributing factor to ASI loss, as they alluded to in the statement about open water "mediating" progressive ASI loss.

     RE: the table shown below comparing Gt/year ice loss between periods.  I find it odd that the amount of ASI loss in 2000s is higher than for the 2010s.  Even multiplying the 2010s number by 1.1 since it only accounts for 2010-2018 (missing 2019) gives a much smaller value of ca. 103 vs. the 384 for the 2000s.

    Wipneus' PIOMAS volume graph for Sept. mininum volume shows change from 2000 to 2009 of ca. 11 to 7 M km3, and ca. 7 to 4 for 2010 to 2019.   That is not directly relevant since the study used the winter (October -April) average ASI volume trend not the summer minimum trend for their ice loss measure.  But I don't see how the losses in 2000-2009 could so much exceed the 2010-2018 value.  And even the 1980s and 1990s rates of winter ASI loss are almost 1.5 and almost 3X higher than the extrapolated Gt/year for 2010s. 

    Even though it is measuring a different month of the year, I do not see why the Wipneus Sept minimum chart would show a consistent trend in losses while this study apparently finds a much lower rate of ASI loss in the 2010s. 

    Finally, they note that the energy used to melt ice only accounts for 3.2% of the net Earth energy imbalance.  While some has gone into the atmosphere and plants, 93% (other source) goes into ocean warming.  That hides the "damage" from us in the sense that heat buried in the ocean is not immediately apparent.  But the bad news is that the ocean has huge thermal inertia.
Once energy is stored there, it stays there for a very long time, essentially forever from a human perspective, and will continue to exert changes on ocean currents, atmosphere (and the weather), marine life, and the remaining ice.

[kassy]

Well the winter ice was thicker over all so there was more to melt out then.

[Glen Koehler]

   Yes, but there was also a lot more summer ice in the earlier decades, yet the PIOMAS volume (e.g. Wipneus chart) shows a steady rate of decline.  So why would winter (Oct-Apr) losses show a 2/3 reduction in loss rate for the most recent decade compared to prior decades, while September minimum losses continued to follow a consistent trend?

[kassy]

They are not so much winter losses as snapshots of the overall loss only taken in winter.

For more details we should take it to the When thread.

[vox_mundi]

Paleo Arctic Ocean Was Covered By Shelf Ice and Filled With Freshwater
https://phys.org/news/2021-02-arctic-ocean-shelf-ice-freshwater.html



The Arctic Ocean was covered by up to 900-meter-thick shelf ice and was filled entirely with freshwater at least twice in the last 150,000 years. This surprising finding, reported in the latest issue of the journal Nature, is the result of long-term research by scientists from the Alfred Wegener Institute and the MARUM. With a detailed analysis of the composition of marine deposits, the scientists could demonstrate that the Arctic Ocean as well as the Nordic Seas did not contain sea-salt in at least two glacial periods. Instead, these oceans were filled with large amounts of freshwater under a thick ice shield. This water could then be released into the North Atlantic in very short periods of time. Such sudden freshwater inputs could explain rapid climate oscillations for which no satisfying explanation had been previously found.

According to their study, the floating parts of the northern ice sheets covered large parts of the Arctic Ocean in the past 150,000 years. Once about 70,000-60,000 years ago and also about 150,000-130,000 years ago. In both periods, freshwater accumulated under the ice, creating a completely fresh water Arctic Ocean for thousands of years.

Their finding is based on geological analyses of ten sediment cores from different parts of the Arctic Ocean, Fram Strait and the Nordic Seas. The stacked deposits mirror the climate history of the past glacials. When investigating and comparing the sediment records, the geoscientists found that an important indicator was missing, always in the same two intervals. "In saline sea water, the decay of naturally occurring uranium always results in the production of the isotope thorium-230. This substance accumulates at the sea floor, where it remains detectable for a very long time due to its half-life of 75,000 years," Walter Geibert explains.

Thorium is absent in the sediments, so saline water must have been absent



How can a large ocean basin, connected by several straits with the North Atlantic and the Pacific Ocean, turn entirely fresh? "Such a scenario is perceivable if we realize that in glacial periods, global sea levels were up to 130 m lower than today, and ice masses in the Arctic may have restricted ocean circulation even further," states co-author Professor Ruediger Stein, geologist at the AWI and the MARUM.

Shallow connections like Bering Strait or the sounds of the Canadian Archipelago were above sea level at the time, cutting off the connection with the Pacific Ocean entirely. In the Nordic Seas, large icebergs or ice sheets extending onto the sea floor restricted the exchange of water masses. The flow of glaciers, ice melt in summer, and rivers draining into the Arctic Ocean kept delivering large amounts of fresh water to the system, at least 1200 cubic kilometers per year. A part of this amount would have been forced via the Nordic Seas through the sparse narrow deeper connections in the Greenland-Scotland Ridge into the North Atlantic, hindering saline water from penetrating further north. This resulted in the freshening of the Arctic Ocean.

... Freshwater release from the Arctic Ocean might also serve as an explanation for some abrupt climate change events during the last glacial period. During such events, temperatures in Greenland could rise by 8-10 degree centigrade within a few years, only returning to the original cold glacial temperatures over the course of hundreds or thousands of years. "We see an example here of a past Arctic climate tipping point of the Earth system.

Glacial episodes of a freshwater Arctic Ocean covered by a thick ice shelf, Nature (2021).
https://www.nature.com/articles/s41586-021-03186-y

[glennbuck]

It is the first time that a commercial vessel sails across the Northern Sea Route in February. The voyage of the Christophe de Margerie from Jiangsu in China to the remote Arctic terminal of Sabetta was made in the Arctic winter dark and through thick sea-ice.

https://thebarentsobserver.com/en/2021/02/arctic-shipper-shows-historical-icebreaking-voyage

[kassy]

thick sea-ice.

Propaganda...that is not thick sea ice. 

[gerontocrat]

thick sea-ice.

Propaganda...that is not thick sea ice. 

Not thick sea ice in February. A hint for the melting season?

[kassy]

Possibly.

Some quotes from:
A changing Bering Sea is influencing weather far to the south, scientists say

...

Hundreds of miles inland from the Bering Sea, at the University of Alaska Fairbanks, physical oceanographer Seth Danielson is monitoring the moving pieces of the climate ecosystem. One standout factor, he said, is the loss of ice in the Bering Sea.

“The waters start warmer in the fall, so we are making less ice. The air temperature is warmer so we are having less ice in the winter,” he said. “At some point, you have to assume that what you think is normal has changed.”

...

The Bering-Chukchi connection
The Bering Sea holds a pivotal role, Danielson said, because of its location at a critical point on the massive marine conveyor belt that regulates the world’s oceans. The Pacific Ocean rests at a higher elevation than the Atlantic Ocean, so water from the Pacific runs downhill through the Bering Strait into the Chukchi Sea, he said.

That means the heat that the Bering collects from the south pours through that narrow strait separating Alaska from Russia. That heat is building as increasingly open and dark-surfaced Bering Sea absorbs more of the sun’s rays rather than reflecting the energy with white ice.

...

Danielson and his colleagues in the UAF oceanography group and other institutions have been able to track the movement of heat from the Bering into the Chukchi with instruments on fixed moorings at strategic spots in the marine system.

That heat flow accelerated in just a few years. In the 2014-to-2018 period, the amount of heat going through the Bering Strait into the Chukchi was about 43 percent higher than the amount prior to 2014, according to the most recent calculations, which Danielson presented at this year’s Alaska Marine Science Symposium, held online in January.

Effects intensify as heat moves north.

Though the Bering Sea is undergoing a well-recognized transformation, with record-low and near-record-low winter ice amounts in recent years, the Chukchi Sea is in some ways changing more dramatically, he said.

Danielson and his colleagues quantified temperature differences in a study published in May of 2020. In the Bering Strait, temperatures increased at a rate of 0.27 degrees Celsius per decade from 1991 to 2015, mooring measurements showed. But in the Chukchi, temperatures increased by 0.43 degrees per decade since 1990, the measurements showed.

Every 1 degree Celsius of warming in the Chukchi delays freeze-up by about three weeks, Danielson said. Such delays are documented in the satellite record, which shows that type of ice extent that used to be normal in October is appearing much later — not until December in recent years.

That delay in freezing means the ocean and atmosphere absorb more heat over longer periods, Danielson said. With the extra heat now cast off by the Chukchi in the fall, “You would heat the whole Arctic by something like a degree (Celsius),” he said, referring to not just all the seas but also all the land above the Arctic Circle. “The Chukchi is a clear center of action for delivering heat to the Arctic,” he said.

....

And there is more about the teleconnections but i found the Arctic stuff more interesting.

https://www.arctictoday.com/a-changing-bering-sea-is-influencing-weather-far-to-the-south-scientists-say/

[glennbuck]

thick sea-ice.

Propaganda...that is not thick sea ice. 

Ye, the music it is like pioneering exploration, where i felt sadness, shock and alarmed!

[binntho]

thick sea-ice.

Propaganda...that is not thick sea ice. 

The video is perhaps not entirely reliable, but the article is interesting. And towards the end of the video, the ice could easily be well over 1 meter thick.

The ice breaker is "50 Let Pobedy" which is designed to break through up to 5 m thick ice.

This expedition says nothing about the state of the ice, but quite a lot about the advances of Russian technologies for dealing with the extremes of hte Arctic.

[Glen Koehler]

      Cloud-Making Aerosol Could Devastate Polar Sea Ice
https://www.quantamagazine.org/cloud-making-aerosol-could-devastate-polar-sea-ice-20210223/
1st paragraph:
     "To climate scientists, clouds are powerful, pillowy paradoxes: They can simultaneously reflect away the sun’s heat but also trap it in the atmosphere; they can be products of warming temperatures but can also amplify their effects. Now, while studying the atmospheric chemistry that produces clouds, researchers have uncovered an unexpectedly potent natural process that seeds their growth. They further suggest that, as the Earth continues to warm from rising levels of greenhouse gases, this process could be a major new mechanism for accelerating the loss of sea ice at the poles — one that no global climate model currently incorporates."   

[kassy]

The CERN scientists found that aerosol particles made of iodic acid could form very quickly — even more quickly than the rates of sulfuric acid mixed with ammonia. In fact, the iodine was such an effective nucleator that the researchers had a difficult time scrubbing it away from the sides of the chamber for subsequent experiments, which required a completely clean environment.

The findings are important for understanding the fundamental chemistry in the atmosphere that underlies cloud processes, Kirkby said, but also as a warning sign: Global iodine emissions have tripled over the past 70 years, and scientists predict that emissions will continue to accelerate as sea ice melts and surface ozone increases. Based on these results, an increase of molecular iodine could lead to more particles for water vapor to condense onto and spiral into a positive feedback loop. “The more the ice melts, the more sea surface is exposed, the more iodine is emitted, the more particles are made, the more clouds form, the faster it all goes,” Kirkby said.

Alpine ice evidence of a three-fold increase in atmospheric iodine deposition since 1950 in Europe due to increasing oceanic emissions

Significance
Our measurements show a tripling of iodine in Alpine ice between 1950 and 1990. A 20th century increase in global iodine emissions has been previously found from model simulations, based on laboratory studies, but, up to now, long-term iodine records exist only in polar regions. These polar records are influenced by sea ice processes, which may obscure global iodine trends. Our results suggest that the increased iodine deposition over the Alps is consistent with increased oceanic iodine emissions coupled with a change in the iodine speciation, both driven by increasing anthropogenic NOx emissions. In turn, the recent increase of iodine emissions implies that iodine-related ozone loss in the troposphere is more active now than in the preindustrial period.

Abstract
Iodine is an important nutrient and a significant sink of tropospheric ozone, a climate-forcing gas and air pollutant. Ozone interacts with seawater iodide, leading to volatile inorganic iodine release that likely represents the largest source of atmospheric iodine. Increasing ozone concentrations since the preindustrial period imply that iodine chemistry and its associated ozone destruction is now substantially more active. However, the lack of historical observations of ozone and iodine means that such estimates rely primarily on model calculations. Here we use seasonally resolved records from an Alpine ice core to investigate 20th century changes in atmospheric iodine. After carefully considering possible postdepositional changes in the ice core record, we conclude that iodine deposition over the Alps increased by at least a factor of 3 from 1950 to the 1990s in the summer months, with smaller increases during the winter months. We reproduce these general trends using a chemical transport model and show that they are due to increased oceanic iodine emissions, coupled to a change in iodine speciation over Europe from enhanced nitrogen oxide emissions. The model underestimates the increase in iodine deposition by a factor of 2, however, which may be due to an underestimate in the 20th century ozone increase. Our results suggest that iodine’s impact on the Northern Hemisphere atmosphere accelerated over the 20th century and show a coupling between anthropogenic pollution and the availability of iodine as an essential nutrient to the terrestrial biosphere.

https://www.pnas.org/content/115/48/12136

Bit more on the aerosols.

[kassy]

New treaty to ban fishing in fishless Central Arctic

...

Pending final ratification, an international accord that also bans fishing in the Central Arctic Ocean will likely take effect later this year. A decade since negotiations began, the treaty – the Central Arctic Ocean Fishing Agreement – may give scientists breathing space to study the rapidly-evolving conditions in the world’s least-trafficked ocean. Fisheries experts hope that if fishing is eventually permitted, it will be managed rationally and sustainably. A disastrous frenzy of unregulated fishing in the 1980s that ruined an adjacent productive fishery, in the Bering Sea, gave ammunition to the agreement’s supporters. The new treaty is a rare international action to “‘prevent the fire’ rather than to ‘extinguish the fire,'” in the words of a recent paper in Marine Policy.

https://yaleclimateconnections.org/2021/02/new-treaty-to-ban-fishing-in-fishless-central-arctic/

[Glen Koehler]

Unless there is some rebound (or an additional crash), we will change over to a melting season thread on March 1st.

     March 1st is the last day without sunrise at 83.50 North.  (According to Google Earth the northernmost point of land in the Arctic is in Greenland at 83.38 degrees). 
     Sunrise/Sunset at 10:42am / 1:14pm on March 2, with day length increasing by about 1 hour per day.  By April 3 the sun is above the horizon 24 hours a day until Sept. 9.

     Table of sunrise/sunset times at
https://www.esrl.noaa.gov/gmd/grad/solcalc/table.php?lat=83.5&lon=-70&year=2021

[vox_mundi]

Polar Space Hurricane Observed for the First Time
https://phys.org/news/2021-03-space-hurricane.html

The first observations of a space hurricane have been revealed in Earth's upper atmosphere, confirming their existence and shedding new light on the relationship between planets and space.

The unprecedented observations, made by satellites in August 2014, were only uncovered during retrospective analysis by scientists at the University of Reading, as part of a team led by Shandong University in China, that confirmed the hurricane and offered clues about its formation.

This analysis has now allowed a 3-D image to be created of the 1,000km-wide swirling mass of plasma several hundred kilometers above the North Pole, raining electrons instead of water, and in many ways resembling the hurricanes we are familiar with in the Earth's lower atmosphere.

Professor Mike Lockwood, space scientist at the University of Reading, said: "Until now, it was uncertain that space plasma hurricanes even existed, so to prove this with such a striking observation is incredible."

"Tropical storms are associated with huge amounts of energy, and these space hurricanes must be created by unusually large and rapid transfer of solar wind energy and charged particles into the Earth's upper atmosphere.

The fact the hurricane occurred during a period of low geomagnetic activity suggests they could be more relatively common within our solar system and beyond. This highlights the importance of improved monitoring of space weather, which can disrupt GPS systems.


Schematic of the space hurricane and its formation mechanism during an extremely quiet geomagnetic condition with northward IMF and a dominant By component.

Qing-He Zhang et al. A space hurricane over the Earth's polar ionosphere, Nature Communications (2021)
https://www.nature.com/articles/s41467-021-21459-y

-----------------------------------------

... This hurricane shows strong circular horizontal plasma flow with shears, a nearly zero-flow center, and a coincident cyclone-shaped aurora caused by strong electron precipitation associated with intense upward magnetic field-aligned currents. Near the center, precipitating electrons were substantially accelerated to ~10 keV. The hurricane imparted large energy and momentum deposition into the ionosphere despite otherwise extremely quiet conditions.

The observations and simulations reveal that the space hurricane is generated by steady high-latitude lobe magnetic reconnection and current continuity during a several hour period of northward interplanetary magnetic field and very low solar wind density and speed.

[Glen Koehler]

Record-high Arctic freshwater will flow through Canadian waters, affecting marine environment and Atlantic ocean currents
https://www.washington.edu/news/2021/02/24/record-high-arctic-freshwater-will-flow-through-canadian-waters-affecting-marine-environment-and-atlantic-ocean-currents/

"Freshwater is accumulating in the Arctic Ocean. The Beaufort Sea, which is the largest Arctic Ocean freshwater reservoir, has increased its freshwater content by 40% over the past two decades. How and where this water will flow into the Atlantic Ocean is important for local and global ocean conditions.

A study from the University of Washington, Los Alamos National Laboratory and the National Oceanic and Atmospheric Administration shows that this freshwater travels through the Canadian Archipelago to reach the Labrador Sea, rather than through the wider marine passageways that connect to seas in Northern Europe. The open-access study was published Feb. 23 in Nature Communications."

https://www.nature.com/articles/s41467-021-21470-3
https://www.nature.com/articles/s41467-021-21470-3/figures/1