The 2024 melting season

[Freegrass]

I think the latest forecast is quite serious. HP all over the Arctic for a very long time + from day 3-5 lots of warm air over the ESS. Already on Worldview you can see nice leads and the sun will hit those...and after that warmth and Sun over the ESS. I know that some people say that it's too cold but all that solar energy will go somewhere: yes, much of it will be reflected by ice back into space but some will be absorbed. So, all in all, I think it might amount to a strong start.

You're right. There's already a lot of open water in the ESS.

But never mind the ice. Look at the temperatures on land.
12°C is going to melt a lot of snow.

And if you look closely, you'll see positive temperatures (0.5°C) deep on the ice.

[Phil.]

Nenana gone:




April 27 5:18AM

[Paul]

I think the latest forecast is quite serious. HP all over the Arctic for a very long time + from day 3-5 lots of warm air over the ESS. Already on Worldview you can see nice leads and the sun will hit those...and after that warmth and Sun over the ESS. I know that some people say that it's too cold but all that solar energy will go somewhere: yes, much of it will be reflected by ice back into space but some will be absorbed. So, all in all, I think it might amount to a strong start.

You're right. There's already a lot of open water in the ESS.

But never mind the ice. Look at the temperatures on land.
12°C is going to melt a lot of snow.

And if you look closely, you'll see positive temperatures (0.5°C) deep on the ice.

I think that's more of the concern really with the PV being weakened as it is, just how early will snow melt be on the Siberian landmasses?

In terms of suns strength and high pressure then as for the ice, it will probably have little effect the ice will no doubt have proper melting weather later on. I also argue high pressure is not always as bad as it gets played out on here, sometimes it's better for the ice to get compacted as it may make the ice pack more resilient although high SSTS could eventually overpower that.

At least the Beaufort is looking colder though and wind direction should mean we shouldn't see openings like we did in 2016/19 although I suspect it's just delaying the inevitable.

[binntho]

But the whole point in this discussion, i.e. that insolation + advection of moist air is a main cause of early melt onset, "moist" in this context most likely means "containing water vapour" - simply because clouds/fog reflect insolation and are thus a negative feedback, while water vapour is opaque to insolation

Rather than "opaque" I think you meant "transparent."

Water is absorbent of IR, whether liquid, gas, or solid.  It approximates a black body in IR, but not at other wavelengths.  Thus, it also radiates IR well.  Thus, overcast days are often even warmer than sunny days.  I suspect overcast days in the arctic promote melt ponds more than sunny days, despite reduced surface insolation.

Thanks for the correction - unfortunately I am unable to edit my original post.

You are of course prefectly right about the effect of certain types of clouds, which are mostly transparent to incoming sunlight but reflect outgoing IR radiation. And of course, cloudiness during winter (when there is no insolation) will have a warming effect, regardless of cloud type.

[binntho]

And I doubt very much that much of any of the water vapour coming up the Bering or from the bogs of Siberia, is going to suddenly precipitate when entering the Arctic. In fact, I suspect that most all of the water vapour stays as it is. If you have evidence to the contrary, please let me know!

Ok, here it is.
...

Thanks. I was mostly thinking about air that has already significantly cooled down before entering the Arctic Ocean, as would frequently be the case at this time of year while there still is snow and ice outside of the Ocean proper. Other than that, normal physics applies of course, with cooling air losing excess vapour as precipitiation.

To clarify: The discussion is about melt onset, and a paper that states that sunny skies and advection of moist air from Bering and Chuckhi seas into the Arctic Ocean seems to be the trigger at this time of year. Somebody claimed that all the moisture would turn to snow, then most of the moisture. To my mind, that seems unlikely as the air will already be cold before entering the Arctic Ocean and thus most likely to keep all moisture in place.

Specific conditions at a specific time, not general physics.

[binntho]

Uniquorn, thanks for your post, I won't clutter up the forum by reposting the lot and it should definitely be read in its totality!

The Bering Strait is indeed full of surprises, and the changes observed over the last decades are very interesting. And of course, you are the specialist when it comes to these things, my interest is purely that of an amateur. My only quibble was with the use of the word "surge" to describe a slow, constant, but possibly fluctuating ocean current.

I took two frames from your original video, two days apart, showing a pulse of salinity entering the Arctic. The front of the pulse moved 50 km in two days, which is 0.3 m/s (a tad over 1 km/hr).

This is surprisingly close to my original estimate: The strait approximately 3 million m² in cross section, which means that 1Sv would pass through at a speed of 1/3 m/s.

NB click to animate!

[Jim Hunt]

Hopefully the moderators will agree that this shock news is worthy of a place in the melting season thread rather than its genesis in the Far Right Great White Con:

https://GreatWhiteCon.info/2024/04/reuters-fact-checks-daily-septic-arctic-sea-ice-nonsense/

To the apparent astonishment of the Septic’s alleged “Environment Editor”, Chris Morrison, Reuters Fact Check has now followed in “Snow White’s” dainty footsteps through the as yet unmelted Arctic snow cover...

A headline touting a small increase in Arctic sea ice on a single date after a decades-long decline is being shared online to suggest that climate-change warnings are a hoax.

But the data show that average sea ice cover in the Arctic is still dropping over the long term and scientists say that minor variations on individual days don’t negate that overall downward trend or the contribution of global warming…

Experts say while the quoted figures 20 years apart are accurate, “cherry-picking” individual dates does not provide a meaningful picture of what is happening in the Arctic.

It is more accurate to look at the data over the long term, which shows  that the extent of Arctic ice has been declining since satellites began continuously recording in 1979.

See also: https://twitter.com/GreatWhiteCon/status/1784549576541700279

Any and all "Likes" and/or "ReXweets" would be much appreciated.

[jdallen]

But the whole point in this discussion, i.e. that insolation + advection of moist air is a main cause of early melt onset, "moist" in this context most likely means "containing water vapour" - simply because clouds/fog reflect insolation and are thus a negative feedback, while water vapour is opaque to insolation

Rather than "opaque" I think you meant "transparent."

Water is absorbent of IR, whether liquid, gas, or solid.  It approximates a black body in IR, but not at other wavelengths.  Thus, it also radiates IR well.  Thus, overcast days are often even warmer than sunny days.  I suspect overcast days in the arctic promote melt ponds more than sunny days, despite reduced surface insolation.

Overcast days are warmer in winter, as the clouds prevent heat loss; the water absorbs IR emanating from the surface, and re-radiates it in all directions (about half back to the surface).  In the summer, clouds absorb incoming solar and radiation, and re-radiates it.  This time of year probably resembles winter more than summer, due to the ice and snow cover.  It will only promote melt ponds if it keeps temps above freezing.  That is not the case yet.

Just so, Walrus.

In summary, melt pond formation is governed by net heat exchange at the surface of the ice, not cloud cover or the lack thereof.

When we have full insolation, that net energy received massively exceeds heat loss out of the atmosphere, permitting significant melt at 2m SSTs as low as -10c.

Cloud cover will reduce the exchange out of the atmosphere, but replaces direct insolation with what is primarily down-welling IR, which doesn’t come close to what is applied to the surface directly.  It can be warmer, but unless heat is available, you won’t get melt.

There are additional factors of course; IF the atmosphere is carrying large quantities of moisture - and by extension latent heat - which can be transported and released via precipitation, specifically rain, you can have very high rates of melt and melt pond formation. 

But following thermodynamics (“TANSTAAFL” - There Ain’t No Such Thing As A Free Lunch) there has to be a significant source of heat to drive phase change.  From late April to late August, direct Insolation wins that contest over cloud cover.
   

[SteveMDFP]

In summary, melt pond formation is governed by net heat exchange at the surface of the ice, not cloud cover or the lack thereof.

When we have full insolation, that net energy received massively exceeds heat loss out of the atmosphere, permitting significant melt at 2m SSTs as low as -10c.

Cloud cover will reduce the exchange out of the atmosphere, but replaces direct insolation with what is primarily down-welling IR, which doesn’t come close to what is applied to the surface directly.  It can be warmer, but unless heat is available, you won’t get melt.

There are additional factors of course; IF the atmosphere is carrying large quantities of moisture - and by extension latent heat - which can be transported and released via precipitation, specifically rain, you can have very high rates of melt and melt pond formation. 

But following thermodynamics (“TANSTAAFL” - There Ain’t No Such Thing As A Free Lunch) there has to be a significant source of heat to drive phase change.  From late April to late August, direct Insolation wins that contest over cloud cover.
 

All this is entirely true, but I was getting at something different about the dynamics of melt pond formation.  Several times in previous melt seasons, we've had periods of arctic overcast,  When the overcast clears, we see a surprising extent of melt pond formation.  I think there's a physical explanation for this pattern.

On overcast days, a higher proportion of radiation that strikes the snow/ice/water surface shifts towards infrared, and away from visible light.  IR and visible light behave very differently at this interface.  The surface heavily reflects or transmits visible light, but being nearly a black body to IR, the IR radiation is readily absorbed, minimally reflected, and transmits remarkably short distances only.  The large bulk of this IR radiation thus goes into the surface only.  Visible light doesn't act this way at the interface.

With increased deposition of radiation at the surface, the IR-heavy overcast days (but not stormy) thus promote melt ponds.  Once formed, melt ponds promote further melting, by lowering albedo for visible light energy.  Melt ponds are an important aspect of the melt season.

[Jim Hunt]

Any and all "Likes" and/or "ReXweets" would be much appreciated.

Gotcha: https://twitter.com/GreatWhiteCon/status/1784835283659235464

[Jim Hunt]

In other Shock News! Gero is currently #1 in the admittedly rather short Daily Septic historical record:

[Jim Hunt]

Gero is currently #1 in the admittedly rather short Daily Septic historical record:

In even more shocking news, Gero and Snow are now invisible in the much shorter Daily Septic historical record.

When viewed from Snow's winter quarters in soggy West Devon at least.

P.S. Snow has now been restored to her former glory. In addition Gero has been duplicated, thanks to an earlier experiment by yours truly.

Tony Heller's loving embrace of Snow White is currently #1, and Gero is down to #2.

[The Walrus]

In summary, melt pond formation is governed by net heat exchange at the surface of the ice, not cloud cover or the lack thereof.

When we have full insolation, that net energy received massively exceeds heat loss out of the atmosphere, permitting significant melt at 2m SSTs as low as -10c.

Cloud cover will reduce the exchange out of the atmosphere, but replaces direct insolation with what is primarily down-welling IR, which doesn’t come close to what is applied to the surface directly.  It can be warmer, but unless heat is available, you won’t get melt.

There are additional factors of course; IF the atmosphere is carrying large quantities of moisture - and by extension latent heat - which can be transported and released via precipitation, specifically rain, you can have very high rates of melt and melt pond formation. 

But following thermodynamics (“TANSTAAFL” - There Ain’t No Such Thing As A Free Lunch) there has to be a significant source of heat to drive phase change.  From late April to late August, direct Insolation wins that contest over cloud cover.
 

All this is entirely true, but I was getting at something different about the dynamics of melt pond formation.  Several times in previous melt seasons, we've had periods of arctic overcast,  When the overcast clears, we see a surprising extent of melt pond formation.  I think there's a physical explanation for this pattern.

On overcast days, a higher proportion of radiation that strikes the snow/ice/water surface shifts towards infrared, and away from visible light.  IR and visible light behave very differently at this interface.  The surface heavily reflects or transmits visible light, but being nearly a black body to IR, the IR radiation is readily absorbed, minimally reflected, and transmits remarkably short distances only.  The large bulk of this IR radiation thus goes into the surface only.  Visible light doesn't act this way at the interface.

With increased deposition of radiation at the surface, the IR-heavy overcast days (but not stormy) thus promote melt ponds.  Once formed, melt ponds promote further melting, by lowering albedo for visible light energy.  Melt ponds are an important aspect of the melt season.

Yes, the melt ponds have a lower albedo than snow or ice.  However, clouds have a higher albedo than melt ponds, but lower than snow or ice.  Hence, once melt ponds have formed, cloudy days have a higher albedo, resulting in less deposition of radiation at the surface.

"As the surface changes during the melt period from snow-covered sea ice to partially snow- melt pond-covered sea ice to totally open water, the albedo of this heterogenous surface will decrease. Because the cloud albedo lies between the albedo of snow and the albedo of dark open water, an increase in cloud cover due to loss of sea ice coverage is expected to partly compensate for the associated albedo decrease and tend to restore the TOA albedo during the sea ice melt period to the pre-melt value. The planetary albedo is determined by reflection from both the surface and the atmosphere."

https://www.nature.com/articles/s41598-019-44155-w#:~:text=As%20the%20sea%20ice%20melts%20and%20ponds%20form%2C,absorbed%20energy%20will%20enhance%20the%20sea%20ice%20melt.

[uniquorn]

some surges maybe more acceptable than others

That ice export from the Barents sea to the Fram strait in 2003 coincided with the beginning of a surge of Atlantic water into the Barents sea and European side of the Arctic ocean. The surge of warm salty Atlantic water was a key to the decline in Arctic ice later in that decade.

Yes, the winds and weather that exported ice also imported Atlantic water into the Barents sea.

And suddenly everybody can claim surges of water going here and there without so much a shred of evidence!

I have on previous occasions pointed out that the Arctic ocean is a watery body of extreme turpitude. Hardly anything moves in there, the few currents are either miniscule or move so slowly as to be easily overtaken by an arthritic tortoise. Only an extremely small fraction of the waters of the Arctic ocean are in movement at any one time. This is not to say that there is no movement - there is, and can have effects in some very localized places, as determined primarily by bathymetry.
<snip>

FOoW was perhaps referring to the pulse of warm Atlantic Water anomalies advected from the North Atlantic towards the Arctic Ocean. So maybe another 6 months before the next one reaches Fram and Barents.

Variability in Atlantic water temperature and transport at the entrance to the Arctic Ocean, 1997–2010
Agnieszka Beszczynska-Mo¨ller, Eberhard Fahrbach, Ursula Schauer, and Edmond Hansen
https://doi.org/10.1093/icesjms/fss056   Published: 18 April 2012

Discussion and conclusions

The main feature observed in the northern Fram Strait from 1997 to 2010 was an increase in the temperature of the AW advected from the North Atlantic towards the Arctic Ocean. These warm anomalies originated from the upstream basins and travelled with a time-lag northwards, being modified along the way by ocean–atmosphere exchanges and lateral mixing with ambient waters. In the North Atlantic and southern Norwegian Sea, a remarkable increase in the AW temperature and salinity has been observed since the 1990s (Turrell et al., 2003). At the Svinøy section in the Norwegian Sea, the first warm event can be recognized between 1997 and 1998 and was followed by the second temperature increase, which started around 2002/2003 (Orvik and Skagseth, 2005; Skagseth et al., 2008). The first warm anomaly arrived at Fram Strait in 1998/1999, and the second one was observed there after 2004. This implies a time-lag of 1–2 years for the advection of anomalous waters from the North Atlantic to the northern Fram Strait, much slower than the mean speed of the slope current (the NwASC and farther north the WSC). The results of Holliday et al. (2008) show that a coherent anomalous temperature and salinity signal can be found all round the northeastern North Atlantic, from the Rockall Trough to the northern Fram Strait.

Anomalies in the core and offshore WSC branches have different signatures owing to their origin from two branches of the NwAC. Mauritzen et al. (2011) show that the volume transport in the eastern slope current (NwASC) has a main temperature mode in the range 8.5–9°C, whereas in the AW originating from the western baroclinic branch of the NwAC, the volume transport is in the main temperature mode of 7.5–8°C. Different advection time-scales for these two branches result in a different cooling rate of the AW before it encounters Polar Water in Fram Strait. There is also a significant lateral eddy exchange between both branches (Rossby et al., 2009; Andersson et al., 2011), which implies that the two branches are not distinct in a Lagrangian sense. A similar situation is found between two branches of the WSC in Fram Strait. The strong lateral exchange is caused by vortices generated by barotropic instability in the WSC core (Teigen et al., 2010) as well by baroclinic instability in the offshore branch (Teigen et al., 2011). The lateral heat exchange through vortices in the WSC can at times be stronger than the heat exchange with the atmosphere.

The warm anomalies passing through Fram Strait can be traced farther in the Arctic Ocean along the boundary of the Eurasian Basin. Polyakov et al. (2005) found a temperature anomaly in the eastern Eurasian Basin in 2004. This anomaly originated in the North Atlantic and took ∼1.5 years to propagate from the Norwegian Sea to the Fram Strait region (the first warm anomaly observed there between 1997 and 1999), and an additional ∼4.5–5 years to reach the Laptev Sea slope. A recent study by Polyakov et al. (2010) shows that the warm pulse of AW that entered the Arctic Ocean in the early 1990s finally reached the Canada Basin during the 2000s. The second warm pulse that entered the Arctic Ocean in the mid-2000s has moved through the Eurasian Basin and is en route downstream. Those authors also claim a possibility of the uptake of anomalous AW heat by overlying layers, with possible implications for an already reduced Arctic ice cover. However, the possible impact of warmer Atlantic water on the shrinking sea-ice cover in the Arctic Ocean is a subject of controversy between different authors, because the Atlantic layer in the Arctic Ocean is shielded from the sea ice by the cold halocline, which suppresses upward heat flux.

Although the potential link between the anomalously warm AW inflow and sea-ice concentration in the Arctic Ocean is not clearly established, the strong influence of the AW temperature on sea-ice conditions around Svalbard is well documented. Cokelet et al. (2008) showed that the region north of Svalbard is characterized by large ocean–atmosphere heat flux, reaching a maximum of 520 W m−2. This region, called Whaler's Bay, is where the main direct interactions between warm Atlantic water and sea ice take place (Rudels, 2010). Rudels (2010) showed that the warmer inflowing Atlantic water implies not only that more heat is released when cooled to freezing temperature, but also that more of the lost heat is going to ice-melt. The effect of a higher AW temperature in the WSC would then be to increase the ice-melt and the area of open water north of Svalbard more than can be anticipated from just the increase in AW temperature alone. Observational support based on summer hydrographic measurements west of Svalbard were also presented by Walczowski and Piechura (2011), who suggested a negative correlation between AW temperature and sea-ice concentration north of Svalbard.
 

my emphasis

[Niall Dollard]

Current status of the sea ice around Svalbard, as assessed by the Norwegian Ice Service.

Ice area there has taken a big rollercoaster ride this spring.

April 29th : 49K below the 1991-2020 average. 8th lowest area for this day of the year.

April 3rd : 75K above the 1991-2020 average. 10th highest area for that day of the year.

February 29th : 50K below the 1991-2020 average. 4th lowest area for that day of the year.

I suspect that this is mostly down to the synoptic conditions. Strong northerlies during March advancing the ice around Svalbard. And when the northerlies ease off, the WSC does its business and melts the ice.

[uniquorn]

https://go.nasa.gov/3QrpdUe light contrast

[Jim Hunt]

The Daily Septic bashing continues over at:

https://forum.arctic-sea-ice.net/index.php/topic,578.msg400013.html#msg400013

However this quote from UCL's Prof. Julienne Stroeve seems relevant in here:

There is no correlation between the winter sea ice extent and how much will melt out in the summer, and we have seen this time and time again.

If Neven is watching, I'm taking your name in Arctic vain at the above link. I hope that's OK with you?

[binntho]

Uniquorn, thanks for another informative post. Talking about "pulses" seems much better than "surges" - and the warm pulses that have been entering the Arctic through the Fram strait are indeed very interesting. And slow moving as well, 1.5 years from Norwegian Sea to Fram Strait, a speed of 1000 km/year or about 100 meters per hour.

[binntho]

...
When we have full insolation, that net energy received massively exceeds heat loss out of the atmosphere, permitting significant melt at 2m SSTs as low as -10c.

Cloud cover will reduce the exchange out of the atmosphere, but replaces direct insolation with what is primarily down-welling IR, which doesn’t come close to what is applied to the surface directly.  It can be warmer, but unless heat is available, you won’t get melt.

...

All this is entirely true, but I was getting at something different about the dynamics of melt pond formation.  Several times in previous melt seasons, we've had periods of arctic overcast,  When the overcast clears, we see a surprising extent of melt pond formation.  I think there's a physical explanation for this pattern.

...

Yes, the melt ponds have a lower albedo than snow or ice.  However, clouds have a higher albedo than melt ponds, but lower than snow or ice.  Hence, once melt ponds have formed, cloudy days have a higher albedo, resulting in less deposition of radiation at the surface.

"As the surface changes during the melt period from snow-covered sea ice to partially snow- melt pond-covered sea ice to totally open water, the albedo of this heterogenous surface will decrease. Because the cloud albedo lies between the albedo of snow and the albedo of dark open water, an increase in cloud cover due to loss of sea ice coverage is expected to partly compensate for the associated albedo decrease and tend to restore the TOA albedo during the sea ice melt period to the pre-melt value. The planetary albedo is determined by reflection from both the surface and the atmosphere."

https://www.nature.com/articles/s41598-019-44155-w#:~:text=As%20the%20sea%20ice%20melts%20and%20ponds%20form%2C,absorbed%20energy%20will%20enhance%20the%20sea%20ice%20melt.

@jdallen seems to be talking about early meltpond formation which can happen at surprisingly cold temperatures, while @SteveMDFP is talking about the phenomenon that we have actually witnessed, when cloud cover disperses and seems to leave meltponds in its wake, although I think this has only happened a lot later in the melt season, when surface temperatures have been above freezing.

@The Walrus, the paper you quote is interesting but does not state that "once melt ponds have formed, cloudy days have a higher albedo" - meltponds have a much lower albedo than open waters, and "cloudy days" can mean a lot of different things!

The paper does however point out that, during insolation over open water, TOA anomalies are higher in clear weather than in cloudy weather, while the opposite is true over ice. Or in other words, over open water, direct insolation is the most effective heat transfer, while over ice, some cloud cover strengthens heat transfer. This is not a new conclusion, we have seen similar in other scientific papers in the past.

Ice albedo, and meltpond albedo, varies quite a lot depending on circumstances, as described in Arctic sea ice albedo: Spectral composition, spatial heterogeneity, and temporal evolution observed during the MOSAiC drift - see image below.

Standard sea ice (once snow has melted) has an albedo of 0.6-0.7, and thin ice had a measured albedo of 0.55 (presumably this varies with the thickness of the ice - the thinner the ice, the lower  the albedo, and probably in an accelerating relationship.

Light melt ponds have an albedo of 0.25-0.32 while the open ocean has 0.06. Which means that melt ponds are closer to ice (at least in the beginning), than to "dark open waters".

All in all, the evidence seem to support what @SteveMDFP says, and which we believe we have observed, but this probably only applies later in the year and not during early melt onset, where direct insolation is probably the main thing as @jdallen points out.

[Freegrass]

Latest Five Day Forecast + Last 5 Days
Wind + Temp @ Surface
Large GIF!

That HPS is warming up Siberia and the Laptev Sea early.
Melting will also start in the Beaufort Sea early next week.
HYCOM is still down.

[Freegrass]

Last time I saw the ice like this, was in 2020. And we all know what happened then.

The only difference is that the ice in 2020 was a lot thinner.

[uniquorn]

5 new SIMB3 buoys have been deployed north of Lincoln Sea. 2024J,K,L,M and N.

They all feature an elongated hull, an Apogee albedometer, and a one-part embedded digital temperature string on the upper section.

2024L also features an experimental array of 10 nodes located around the buoy measuring snow thickness. 4 are looking healthy, 2024K looks like it is already struggling to provide data.

Albedometers offer the opportunity to test top of buoy temperature versus air temperature as an estimation of insolation.

[Niall Dollard]

Thanks Uniquorn for the update. Look forward to seeing this data.

For anyone who has wondered what it looks like, Mosaic made this video of an SIMB3 deployment a few years ago.

[Jim Hunt]

5 new SIMB3 buoys have been deployed north of Lincoln Sea. 2024J,K,L,M and N.

Thanks. I can't keep up 

Will you be posting temperature profiles in the not too distant future?

[cjp]

+1 or 2 more out today and 1 tomorrow. 3 in total will have our experimental SnowTatos remote node systems. Each of the nodes gives "surface_distance", but no GPS, so they are just for statistical quantification of snowpack variation.

This one was turned on 30 min ago:
https://www.cryosphereinnovation.com/deployment/301434060106870

I'm still working on the documentation but in the meantime, I'm happy to answer any question you might have about these. They were a bit of a pain to build and we've had some failures already (K, M, kinda), but hoping the remaining go out smoothly.

[uniquorn]

Quick analysis on SIMB3 2024J

Looks like 2 4cm snow which was affected by insolation on apr30 allowing whatever filled above the freeboard to be affected by lesser insolation on may2-3 with possible melt late may3. Definitely not melt.
Not sure what makes incident-reflected go negative, moonlight?

https://go.nasa.gov/3Uumcnh

[Jim Hunt]

I'm happy to answer any question you might have about these.

Thanks for the info Cameron, and as it happens I do have a question.

I haven't seen any suspicious dots in and around the Lincoln Sea on Marine Traffic etc.

How were the recent set of buoys deployed?

[uniquorn]

Maybe this? Used in the Beaufort
https://www.cryosphereinnovation.com/deployment/301434060407510

[cjp]

I'm happy to answer any question you might have about these.

Thanks for the info Cameron, and as it happens I do have a question.

I haven't seen any suspicious dots in and around the Lincoln Sea on Marine Traffic etc.

How were the recent set of buoys deployed?

Uniquorn nailed it -- these were all deployed via plane taking off from two very remote outposts in northern Greenland. That photo is from a different deployment in the Beaufort but same idea.

It's cool to see that area of the globe filled in with some dots. Should have one more (the final) buoy going out today, weather pending.

[cjp]

Another question for the group. Are you all interested in historical mass balance buoy data?

I'm thinking of crawing the old IMB website (https://imb-crrel-dartmouth.org/archived-data/) and putting all the data on our platform. This would create webpages, programmatic access, metadata support, everything, for all buoys going back to 2000.

I also have a lat/long filter in beta that will allow deployment filtering by lat/long and date on the globe on our /data page. You can draw a box on the globe and it will show you all deployments that have overlapped that area, as well as how much (%) time the spent there.

It will take some time so curious if you all would find this useful.

[HapHazard]

Looks like things will heat up a bit on the Atlantic/Fram front.

[uniquorn]

Another question for the group. Are you all interested in historical mass balance buoy data?

I'm thinking of crawing the old IMB website (https://imb-crrel-dartmouth.org/archived-data/) and putting all the data on our platform. This would create webpages, programmatic access, metadata support, everything, for all buoys going back to 2000.

I also have a lat/long filter in beta that will allow deployment filtering by lat/long and date on the globe on our /data page. You can draw a box on the globe and it will show you all deployments that have overlapped that area, as well as how much (%) time the spent there.

It will take some time so curious if you all would find this useful.

Definitely for me, an easy quick comparison with older SIMB's would occasionally be useful, but there might not be much interest generally for it to be worth your time.

[Jim Hunt]

Are you all interested in historical mass balance buoy data?

I don't know about anybody else but I am certainly interested, not least because some of my own data has gone AWOL.

If that project goes ahead perhaps you could start with 2006C?

[Freegrass]

Latest Five Day Forecast + Last 5 Days
Wind + Temp @ Surface
Large GiFs!

A new hot air bubble is splitting off from the Jetstream in the coming days. But from the Atlantic side this time, pushing temperatures up above freezing.

Melting will start in 3 places now. The Beaufort, the Siberian coastline, and the Atlantic side.

[uniquorn]

Quick analysis on SIMB3 2024J

Looks like 2 4cm snow which was affected by insolation on apr30 allowing whatever filled above the freeboard to be affected by lesser insolation on may2-3 with possible melt late may3. Definitely not melt.
Not sure what makes incident-reflected go negative, moonlight?

https://go.nasa.gov/3Uumcnh

Obviously that analysis was too quick. Should be 33cm snow, is perhaps an unusual floe, fantastic detail below.
I wonder what the co-located instrument is?

https://www.cryosphereinnovation.com/data

SIMB3 2024J
Ice Thickness 176cm
Snow Depth 33cm
Ice Type FYI/MYI Conglomerate Floe
First Year, saline ice on the surface at the exact deployment location, but there is a clearly multiyear hummock 20 ft away, so this is at least in some way MYI. Deep snow prevents really determining the nature of the floe more broadly. Seems likely we deployed in a melted thru pond or in a FYI component of a conglomerate ice floe. Quickly drilling other places on the floe, aside from the obvious hummock, yields similar ice thickness, so if MY, the floe appears to have barely survived summer

SIMB3 2024K
Ice Thickness 280cm
Snow Depth 35cm
Ice Type Level MYI, likely 2nd Year
Large pan level ice. No evidence of hummocks but top of ice appears definitely to be composed of fresh ice (MY) for about 75 cm. Likely second year ice that experienced little surface melting last summer. Smooth enough that we landed directly on the deployment floe rather than adjacent on a refrozen lead as is more typical. This instrument is experiencing transmission lapses and is currently being updated with position data from a collocated instrument.

SIMB3 2024L
Ice Thickness 196cm
Snow Depth 36cm
Ice Type MYI


SIMB3 2024M
Ice Thickness 245cm
Ice Type MYI
Snow Depth 23cm
Undeformed MYI pan. Deployed on the side slope of a hummock about 15 feet from the top to (hopefully) avoid placing in a melt pond. This instrument is experiencing transmission lapses and is currently being updated with position data from a collocated instrument.

SIMB3 2024N
Ice Thickness 189cm
Snow Depth 41cm
Ice Type MYI, but part of a FYI-MYI conglomerate.

SIMB3 2024O
Ice Thickness 172cm
Snow Depth 51cm
Ice Type MYI

SIMB3 2024P
Ice Thickness 216cm
Ice Type MYI
Snow Depth 19cm
Hummocky MY with large thickness variability floe. 300m diameter in pretty ridged area. Had to look around a while. Not a big a floe as we would like, but constrained by fuel and flying under low ceiling. Lots of new ridging in area. Floe too thick in some places to drill. Found ~4 m several places before settling on a thinner area for deployment. May pond, but not for sure. Seemed the topography causing the thickness difference was more on the bottom of the ice than reflected on the surface. Equipped with SNOTATOES

SIMB3 2024Q
Ice Thickness 251cm
Snow Depth 46cm
Ice Type MYI
1 km size level multi year floe. Deep snow. Ice seems relatively uniform thickness with limited hummock formation. Drilled also ~2.5 m thick in couple places next to plane.

SIMB3 2024R
Ice Thickness 240cm
Snow Depth 26cm
Ice Type MYI
On a hummocky multiyear floe. Has thicker appearance than other floes we’ve been on during ARCSIX deployments due to substantially hummocked surface, expecting this floe to be thicker and older, but it but drills about the same - 2.5 m. Maybe deformation is the basis of the higher hummocks, or maybe this ice is just older and several years of surface melt have deepened its topography but not thickened it. Equipped with SNOTATOES.

[KenB]

... Equipped with SNOTATOES.

OK, can anyone shed some light on this amusing bit of buoy description?  Google doesn't seem to have a clue. TIA!

[uniquorn]

<>
www.cryosphereinnovation.com/data
2024L also features an experimental array of 10 nodes located around the buoy measuring snow thickness.

I suppose they look a bit like potatoes. I don't know if they are all deployed at the same height.

[KenB]

I suppose they look a bit like potatoes. I don't know if they are all deployed at the same height.

Thanks.  Further poking around suggests that a 'snow pinger' is a sonar device on a mast pointed downward.  These Snotatoes (elsewhere "snow-tatos") appear to be networks of such pingers.  I haven't found any pictures or engineering credits yet.  Clever naming, though.   

[SteveMDFP]

I suppose they look a bit like potatoes. I don't know if they are all deployed at the same height.

Thanks.  Further poking around suggests that a 'snow pinger' is a sonar device on a mast pointed downward.  These Snotatoes (elsewhere "snow-tatos") appear to be networks of such pingers.  I haven't found any pictures or engineering credits yet.  Clever naming, though.

Images of "snow pingers" -- land-based, not sea-based, no resemblance to potatoes, slides 3 and 4:
https://slideplayer.com/slide/14588493/

[uniquorn]

SIMB3 2024L snowtato in situ, albedometer, flight path and aerial shot.

Many more deployment images of all the 2024 buoys available from https://www.cryosphereinnovation.com/data

Not sure what makes incident-reflected go negative, moonlight?

Buoy shadow in low sun?

[cjp]

Yup. As you all mostly figured out, SnowTatos are little nodes mounted on stakes with rangefinders on them pointing down at the snow. They connect to the SIMB3 via radio.

They do not have any position data. It their current form they are strictly for getting a statistical understanding of snowpack heterogeneity. These are very new and have never been deployed before until now!

[Jim Hunt]

They connect to the SIMB3 via radio.

You're drifting into my "professional" area of alleged "expertise" Cameron.

Can you be more specific about the type of "radio" employed?

[Freegrass]

Latest Five Day Forecast + Last 5 Days
Wind @ Surface + Total Precipitable Water
Large GiFs!

You could also call this the heat import map, and there's a lot of heat coming in.

[nadir]

The ECMWF hints some warming from the North America side in about a week over the Beaufort.
Zero snow cover reaches anomalously high latitudes for Canada and Alaska, like last year.

Rutgers NH April 2024 snow cover is a new record low.

Edit: the recent big openings in Beaufort sea seem to stay open already. The whole Beaufort sea is quite fractured by now!

[HapHazard]

The ice seems to be very mobile over the last few weeks. Just an eye test, mind you.

[Freegrass]

Latest Five Day Forecast + Last 48h
Wind + Temp @ Surface
Large GiF!

A massive LPS is going to launch the melting season in earnest next week. These lows have a tendency to shift, so let's wait and see what's actually going to happen. Just a minor shift south can keep it behind the mountains of Alaska. But it's been on the charts for a while now, without much change. So it looks like we're in for a mighty start of the melting season, with lots of wind and heat blowing over the ice.

The Siberian coastline is getting "restored" by favorable wind and freezing temperatures.

[Freegrass]

The ice seems to be very mobile over the last few weeks. Just an eye test, mind you.

Where the ice hasn't been very mobile is down the Fram strait. Winds have been very favorably for little to no export in the last few weeks.

[SteveMDFP]

The ice seems to be very mobile over the last few weeks. Just an eye test, mind you.

Where the ice hasn't been very mobile is down the Fram strait. Winds have been very favorably for little to no export in the last few weeks.

Fram export tends to be highly variable, and also cyclic.  It tends to reach a peak during the winter months, and falls dramatically during the summer.  For the arctic ice overall, the amount lost through the winter peak is probably much more important than the amount lost during the summer doldrums.

[Freegrass]

Fram export tends to be highly variable, and also cyclic.  It tends to reach a peak during the winter months, and falls dramatically during the summer.  For the arctic ice overall, the amount lost through the winter peak is probably much more important than the amount lost during the summer doldrums.

I don't disagree often with you, if ever, but I think you've got this one wrong.

During winter export, the increased mobility of the ice creates leads. Leads that freeze up quickly again in winter, restoring volume. And during that time, the Fram acts like a kind of pressure valve, where excess ice gets exported, sometimes helped by favorable winds.

But when you lose the ice right now, in the "pre-season" so to say, that ice doesn't get replaced anymore, because it's too warm already for the leads to freeze back up again. And so export comes to a halt in summer.

So whatever we lose right now, is more harmful than what we lose in winter in my humble opinion.

[kassy]

For the overall situation the most important things is probably the amount of volume transported.

You can slightly change Freegrass argument. The lack of export recently is better then if it had continued.

But now we sort of need a graph of export over the seasons, or just the memory of those watching it more closely but doesn´t it usually slow down during this time  of the year?