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Author Topic: Arctic Ocean salinity, temperature and waves  (Read 91538 times)

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #600 on: June 10, 2020, 09:33:17 PM »
my interpretation is eddies forced by the Atl. current accelerating down St. Anna...
Though there was already low concentration ice there, I think yesterday's event is more likely due to rain. Jayw posted a good rammb showing it.
The concentric circles look like artifacts. Should wait till tomorrow before thinking about them.
« Last Edit: June 10, 2020, 09:41:36 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #601 on: June 10, 2020, 11:59:08 PM »
Curious what might be causing incoming atlantic water to be upwelling. Initial impression is that the saltier water is going down when it has the opportunity.
To clarify, I consider Atlantic water incoming until it begins the return journey to the Fram. Furthest reach is the ESS, west north of Wrangel Island. A quick search found this. I hope you find it helpful.

https://www.ocean-sci.net/14/293/2018/os-14-293-2018.pdf
Quote
Upwelling in the Arctic
In their seminal 2003 paper mentioned above, Carmack and Chapman applied a numerical model to study shelf–basin exchange on the Beaufort Sea shelf and argued that decreased ice concentrations will enhance upwelling in the area.
The argument goes like this: when a thick ice cover lies like a lid on the ocean, it absorbs most of the wind stress instead of transferring it to the underlying ocean. When the ice edge recedes far  enough  north  that  the  shelf  break  is  exposed,  however, the winds can move around the surface waters more easily. Sustained easterlies, for example, will lead to a northward Ekman transport, and where the shelf is shallow enough that it affects surface currents (see Figs. 2 and 3), deeper waters are drawn up to balance the off-shelf transport. This argument was reinforced by a number of studies conducted in the Pacific Arctic (Williams et al., 2006; Schulze and  Pickart,  2012;  Spall  et  al.,  2014;  Arrigo  et  al.,  2014;Lin et al., 2016), which directly extended earlier direct observations  of  shelf  break  upwelling  dating  back  to  at  least the 1980s (e.g. Aagaard et al., 1981). A detailed study (Spallet al., 2014) on the dynamic response during one particularly impressive example of shelf break upwelling in the Chukchi Sea (Arrigo et al., 2014) demonstrated potentially large contributions to primary productivity in that area. The  idea  has  since  caught  on  to  explain  or  project  marine productivity also in other regions of the Arctic Ocean, for example at the Barents Sea shelf break. There it has appeared  both  in  numerous  personal  communications  among the community working with the physical and ecological environment of the Barents Sea and a number of published articles (see e.g. Falk-Petersen et al., 2014; Tetzlaff et al., 2014;Wassmann et al., 2015; Hunt et al., 2016; Våge et al., 2016;Haug et al., 2017). Thus it might appear as if shelf break up-welling is currently being cemented as a universal paradigm to conceptualize the “new” Arctic Ocean where global climate  change  is  taking  us.  We  will  argue  that  some  of  the regional differences cannot be ignored when discussing what governs productivity in the various shelf regions.
« Last Edit: June 11, 2020, 11:34:14 PM by uniquorn »

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Re: Arctic Ocean salinity, temperature and waves
« Reply #602 on: June 11, 2020, 01:04:40 AM »
This is very interesting stuff uniquorn. Thanks for sharing.

I note the paper's emphasis that there is significant regional difference in upwelling potential and that they specify the shelf under the Beaufort off CA and AK to be the region where this is most likely to be significant.

I'm taking a break from the cryosphere. Thanks for your contribution to the discussion and my understanding of the topic.


Bruce Steele

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Re: Arctic Ocean salinity, temperature and waves
« Reply #603 on: June 11, 2020, 01:15:35 AM »
https://www.researchgate.net/publication/339766641_Wind-Driven_Coastal_Upwelling_Near_Large_River_Deltas_in_the_Laptev_and_East-Siberian_Seas

“The Lena, Kolyma, and Indigirka rivers are among the largest rivers that inflow to the Arctic Ocean. Their discharges form a freshened surface water mass over a wide area in the Laptev and East-Siberian seas and govern many local physical, geochemical, and biological processes. In this study we report coastal upwelling events that are regularly manifested on satellite imagery by increased sea surface turbidity and decreased sea surface temperature at certain areas adjacent to the Lena Delta in the Laptev Sea and the Kolyma and Indigirka deltas in the East-Siberian Sea. These events are formed under strong easterly and southeasterly wind forcing and are estimated to occur during up to 10%–30% of ice-free periods at the study region. Coastal upwelling events induce intense mixing of the Lena, Kolyma, and Indigirka plumes with subjacent saline sea. These plumes are significantly transformed and diluted while spreading over the upwelling areas; therefore, their salinity and depths abruptly increase, while stratification abruptly decreases in the vicinity of their sources. This feature strongly affects the structure of the freshened surface layer during ice-free periods and, therefore, influences circulation, ice formation, and many other processes at the Laptev and East-Siberian seas.”



uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #604 on: June 11, 2020, 11:30:19 PM »
https://www.mdpi.com/2072-4292/8/1/4/htm
Sea-Ice Wintertime Lead Frequencies and Regional Characteristics in the Arctic, 2003–2015
by Sascha Willmes and Günther Heinemann
Quote
3.4. Spatial and Temporal Lead Dynamics
If the lead aggregation is performed for the entire period of investigation from 2003 to 2015, we obtain valuable insight in the general pattern of lead occurrences in the entire Arctic (Figure 5). As in the annual maps, the MIZ as well as the characteristic polynya regions are well represented by high lead frequencies, whereas the opposite is again found for fast-ice regions. The position of the fast-ice edge in the East Siberian Sea is characterized by higher variability than e.g., in the Laptev Sea. Again, the Beaufort Sea is revealed as an area of major lead activity within the pack ice zone (A). Major shear zones and the associated higher frequency of leads are generally found in the proximity of islands and continental coasts. In addition, smaller characteristic features are highlighted in the presented map, e.g., Hanna Shoal, in the Northern Chukchi Sea (B, [23,37]), is clearly revealed as a significant hot spot of high lead frequencies in the presented map. A band of slightly enhanced lead activity that reaches from the central Beaufort Sea to the new Siberian Islands is visible (C) and in the East Siberian Sea, some less known features exhibiting high lead frequencies are indicated north of the Kolyma Gulf (D). They seem to stem from the presence of several small shoals in this region. An enhanced lead activity is also found in the outflow of the Vilkitzky canyon in the western Laptev Sea (E) and in the shear zone east of Severnaya Zemlya (F). In the northwest of Franz-Josef Land, an elongated region of high lead frequencies (G) is also revealed. As the features shown in E and G are probably not connected shear zones, we speculate that they might be promoted by bathymetric effects (see discussion). The region North of Greenland, at the western edge of the Transpolar Drift stream (H) is also characterized by a higher frequency of leads as compared to the surrounding region.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #605 on: June 15, 2020, 05:30:44 PM »
For future reference.
The 12z models and 00z EURO the 12z euro isn't out yet have backed off considerably with the dipole in the long range.

Instead of setting up a full or 3/4 dipole the models slide the Eurasian vortex over the pole/Atlantic side and merge it with the GIS vortex which won't budge.

This keeps the torching over the Pacific half.

It's not a good pattern by any means but it definitely is much better than the entire CAB getting the roast.

This kind of thing is what will keep 2020 from passing 2012 in the end.

We'll see

Yep, we've seen this time and again in the last 8-9 years. It's a pattern and I think part of the reason for this strong +PV tendency has been due to a marked increase in low-level baroclinicity and eddy kinetic energy as the mid-high lats warm faster in summer than the basin proper. It is providing a transient negative feedback by preferentially favoring storms over the basin during the summer months (on the cold side of the jet). This retards melt and slows down the year-to-year summer progression. Of course, eventually the warming signal will overwhelm this, but it may take another 20 years to do so (the occasional year like 2016 nonwithstanding). Eventually, increasing warming over land will cause the warm conveyor belts on these storms to start doing enough damage to offset the shielding effect and destroy ice cover anyways. We may end up seeing a fairly long period of not much change -- followed by a quick transient period to sea-ice free, followed by decoupling of the troposphere from the stratosphere in the autumn and subsequent large hits to winter ice volume recoveries. Nakamura et. al's BoE experiments suggested as such a few years back.

And I suspect 2007 and whatever future year(s) this happens will be seen as the turning points.

If you're looking for ocean-driven signals as well, simply look at the trend of shoaling along the Atlantic-inflow stream and heat content storage coming from the Chukchi. They're pointing to the 2040s as well. Incidentally, this is around the same time aragonite undersaturation in the Arctic begins to show up, too (aragonite undersaturation starts in the 2030s around Antarctica). Full-on ecosystem disruption seems pretty ripe around that time.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #606 on: June 17, 2020, 02:06:19 AM »
A one week look at the Bering Strait and Chukchi using band I4 shortwave.  The clouds and daily jump are a bit distracting, but one can see the warm Chukchi waters reading into the pack, as well as Bering inflows.
I reversed the colors to make it easier on the eyes.
Click to run.
« Last Edit: June 17, 2020, 10:48:11 AM by JayW »
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uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #607 on: June 22, 2020, 11:31:10 AM »
uni-hamburg amsr2-uhh, chukchi, may10-jun21.
forum still resizing gifs wider than 580px
« Last Edit: June 22, 2020, 11:36:31 AM by uniquorn »

Bruce Steele

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Re: Arctic Ocean salinity, temperature and waves
« Reply #608 on: June 22, 2020, 05:47:24 PM »
Here is a PowerPoint ( large file ) on melt ponds, white ice , albedo , light scatter . Lots of pictures that we are missing this year . A nice primer on light and ice that helps make sense of the ITP WHOI data..

http://www.cgd.ucar.edu/events/20180409/files/h/Perovich_Wednesday.pdf


uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #609 on: June 28, 2020, 03:43:05 PM »
Nice.
mosaic pbuoy movement over the yermak plateau. Large, to keep buoy separation, so maybe temporary.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #610 on: June 30, 2020, 11:26:53 PM »
It occurred to me that sea ice age would highlight ice movement, particularly in the beaufort.
NSIDC, EASE-Grid Sea Ice Age, jan2000-jun2020, 7.3MB. Probably best viewed at half speed.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #611 on: July 02, 2020, 12:41:33 PM »
A quick look at the latest simb386840 data in the beaufort appears to confirm recent air temps over 15C though that doesn't agree with the chart data from the website which may be surface temp. Assuming this is string data the ice looks in a cooler state than that in the mosaic area.
basic chart, few labels
1593644013 converts to Wednesday July 01, 2020 23:53:33 (pm) in time zone Europe/London (BST)


« Last Edit: July 02, 2020, 07:54:21 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #612 on: July 02, 2020, 08:11:13 PM »
A bit of coding and we have more recent data from 386840. Just need  to convert the timestamp(EST) to readable date. Does anyone understand this format?
I take it back about the state of the ice. The temperature gradients look pretty much the same.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #613 on: July 02, 2020, 08:56:01 PM »
Some recent data from simb 387850 (mosaic#3) while it is set up.
That looks a lot like a melt pond or cavity warming and cooling towards the end.
« Last Edit: July 02, 2020, 09:02:35 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #614 on: July 03, 2020, 10:59:47 PM »
Update on whoi itp buoys 104, 113, 114, 117 and 118 in the Beaufort with data at 6m depth.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #615 on: July 04, 2020, 10:42:20 PM »
Had a look at whoi itp114 first, 7-250m depth, sep2019-jul2020

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Re: Arctic Ocean salinity, temperature and waves
« Reply #616 on: July 05, 2020, 02:07:34 AM »
The temperature spike on ITP 114 microcat data looks like it almost hit zero at 6 meters although it has settled back to -1.24. The other buoy microcat or SamiCO2 stations on 104, 113, 114, 117, 118 temperature readings are from about -1.39 to -1.30 at 5-6 meters. Bottom melt everywhere in the Beaufort.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #617 on: July 06, 2020, 11:29:59 PM »
closer to -0.9C

Bruce Steele

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Re: Arctic Ocean salinity, temperature and waves
« Reply #618 on: July 06, 2020, 11:50:54 PM »
Uniquorn, The ITP buoys all show a similar spike then a drop. I have a theory as to why. Melt ponds form as insolation  peaks. Cracks form which allows surface fresh water to drain, decreasing salinity and reducing temperatures of surface waters below the ice.
Light penetration is reduced as white ice is the result of the surface water draining.
On the Sami data on ITP 118 the pCO2 sensor showed a rapid drop in pCO2. This may be due to
a phytoplankton bloom absorbing Dissolved CO2 from surface waters.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #619 on: July 07, 2020, 12:08:04 AM »
You may be right about itp118 Bruce Steele, but there was a lot less cloud over itp114 during the days with the high peak. click to run

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Re: Arctic Ocean salinity, temperature and waves
« Reply #620 on: July 07, 2020, 03:24:43 AM »
Uniquorn, The ITP buoys all show a similar spike then a drop. I have a theory as to why. Melt ponds form as insolation  peaks. Cracks form which allows surface fresh water to drain, decreasing salinity and reducing temperatures of surface waters below the ice.
Light penetration is reduced as white ice is the result of the surface water draining.
On the Sami data on ITP 118 the pCO2 sensor showed a rapid drop in pCO2. This may be due to
a phytoplankton bloom absorbing Dissolved CO2 from surface waters.
Shouldn't this be decreasing salinity and increasing temperatures of surface waters below the ice? The fresh water is near 0C while the water below is supposed to be at -1.8C.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #621 on: July 07, 2020, 05:03:09 AM »
Oren, I was thinking the creation of white ice as surface ponds drained and the reduction of visible and UVR resulted in less heat to surface water below the ice via a reduction in insolation. Here is an excerpt from an article I posted month ago.

Stage I Prior to Melt Pond Onset on 15 June

Only 0.02 ± 0.01 of incoming PAR was transmitted through the snow-covered ice and spatial variability of light transmission did not change noticeably.

Stage II From 15 to 22 June

Once melt water became visible in large stretches at the ice surface, T¯(PAR)
increased by an order of magnitude to 0.31 on 22 June, while under-ice irradiance became increasingly variable.

Stage III From 23 June to 2 July

A short snowfall event followed by an enhanced surface melt resulted in discrete areas of white ice and melt pond, defining stage III. PAR transmittance and its spatial variability did not increase further during this stage. In fact, T¯(PAR)
 measured along the ND transect decreased from 0.23 to 0.16.

The observed large drop in T¯(PAR)
 measured along the ND transect on 28 June was attributed to the snowfall event. Unfortunately, surface albedo was not measured that day. Repeated measurements along this transects also showed more pronounced transmittance peaks beneath melt ponds while PAR transmittance below white ice became less variable over time (Supplementary Figure S3). These high transmittance values of discrete surface ponds became pronounced as outliers in the boxplots after the surface flooding in stage III. The larger areas of white ice transmitting less PAR compared to ponded ice also resulted in a skewed distribution and the median to be less than the calculated mean for most of the days within stage III. On the last sampling day, the variability in measured under-ice PAR levels decreased while T¯(PAR)
 remained unchanged at 0.20. As shown in the aerial drone image of the sampling area on 2 July (Figure 4E), more white ice had emerged at the surface due to ongoing drainage of melt ponds, leading to a drop in the melt pond coverage and a more uniform sea ice surface. It should be noted that the proposed stages of changes in T¯(PAR)
 are different from the stages of melt pond evolution described elsewhere (Eicken et al., 2002).

For the comparison of measured mean PAR transmittance and length-weighted average transmittance, T¯LW(PAR)
 was calculated for all D transects. To do so, T(PAR) values of 0.16 to 0.24 beneath white ice and 0.25 to 0.40 beneath ponded ice, measured along four destructive transects, were used. As shown in Figure 5B, T¯(PAR)
 and T¯LW(PAR)
 were not significantly different (t(12) = 0.005, p = 0.996) over the sampling period.

The increase in the transmission of one wavelength (305 nm) in the UVB spectrum and three wavelengths (325, 340, and 379 nm) in the UVA spectrum at 2 m is shown for all transects over the sampling period (Figure 5C). Beneath snow-covered sea ice in stage I, T¯(UVA)
, ranged from 0.01 to 0.02, while UVB radiation was not detectable. It is noted that surface and transmitted irradiance were integrated over the UVA wavelength spectrum (320–400 nm) prior to estimating T¯(UVA)
. With melt pond onset, T¯(UVA)
increased to 0.26 by the end of stage II on 22 June. Also, UVB radiation was detectable beneath the ice cover with a T¯(305nm)
 of 0.01. In stage III, transmission of UVA radiation did not increase further, displaying a mean of 0.21 ± 0.05 for D and ND transects. However, T¯(305nm)
 was on average greater during stage III than stage II, reaching a mean value of 0.07 ± 0.06. During stage III, UVR transmittance remained relatively consistent, while the variability in measured under-ice UVR levels decreased. Furthermore, UVR transmission through melt ponds was twice as high than through white ice. TWI(305nm) and TMP(305nm) ranged from 0.03 to 0.08 and 0.11 to 0.14, respectively

https://www.frontiersin.org/articles/10.3389/fmars.2020.00183/full
« Last Edit: July 07, 2020, 05:09:40 AM by Bruce Steele »

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Re: Arctic Ocean salinity, temperature and waves
« Reply #622 on: July 07, 2020, 05:20:35 AM »
Good point, drainage increases albedo and reduces energy available below the ice. I was thinking of the direct temperature of the draining water.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #623 on: July 07, 2020, 05:54:20 AM »
Oren, I have no idea if there has been a recent draining of melt ponds. I just remembered that draining melt ponds reduces light/ UVA in surface water. When I saw the 6 Meter temperature spikes at the ITP buoys it just seemed similar to the paper, timing seems similar also.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #624 on: July 07, 2020, 09:41:34 PM »
beaufort temperatures at 6m depth, day 180-186
'quickly' thrown together
« Last Edit: July 08, 2020, 10:52:30 AM by uniquorn »

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Re: Arctic Ocean salinity, temperature and waves
« Reply #625 on: July 07, 2020, 10:51:35 PM »
Drift charts for those buoys to show locations of these well above melting point temperatures under the ice.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #626 on: July 07, 2020, 11:05:27 PM »
Seems good support for Hycoms prediction of rapid export of thickest ice from CAB along Beaufort and Chukchi Alaskan coast to soon be cut off by rapid meltout starting from centre out to coast of these seas.
Do we have any active sensor buoys in centre of these seas Uniquorn? [Edit: oops, answer is yes, missed 114 on your chart]
Click to play animation:
« Last Edit: July 07, 2020, 11:13:55 PM by OffTheGrid »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #627 on: July 08, 2020, 10:51:58 AM »
To clarify, post #624 shows temperatures at 6m depth. Temperatures just beneath the ice are not measured by these buoys.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #628 on: July 11, 2020, 10:09:58 PM »
Rough check of Beaufort buoy drift timing with worldview, apr1-jul10 4.6MB

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #629 on: July 11, 2020, 11:22:04 PM »
whoi itp buoy drift speed, iabp data, mar30-jul11

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Re: Arctic Ocean salinity, temperature and waves
« Reply #630 on: July 12, 2020, 08:34:52 AM »
Imagine that valuable data lost in 116. I'm so sad right now.  :(
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Re: Arctic Ocean salinity, temperature and waves
« Reply #631 on: July 12, 2020, 05:50:37 PM »
Rough check of Beaufort buoy drift timing with worldview, apr1-jul10 4.6MB
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uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #632 on: July 12, 2020, 11:34:35 PM »
Rough check of Beaufort buoy drift timing with worldview, apr1-jul10 4.6MB
rough check of Pagophilus doing a rough check

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #633 on: July 14, 2020, 10:29:24 PM »
If macid is around I'd really like to see an update of this

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #634 on: July 14, 2020, 11:12:58 PM »
Timmermans 2018: Fate of the Halocline Heat and arctic ocean stratification

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Re: Arctic Ocean salinity, temperature and waves
« Reply #635 on: July 17, 2020, 12:51:46 AM »
Comparison of bands I2 and I4. Attempting to highlight the highest ssts in relation to the ice.

First attachment, Nares entrance in lower right.

Second is part of the chukchi, note the ssts are cooler than the ice in the upper left.  The warm plume is attacking the ice edge in the center.

Both need a click.  Contrast boosted.
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Re: Arctic Ocean salinity, temperature and waves
« Reply #636 on: July 17, 2020, 04:54:56 AM »
Interesting eddies along 75°N in the northern ESS.  What are the chances the shelf break is there?
Click it.
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Re: Arctic Ocean salinity, temperature and waves
« Reply #637 on: July 17, 2020, 10:34:43 AM »
Interesting you chose Lincoln sea. I've been wondering if the open water north of CAA Greenland is evidence of coastal upwelling. The ice doesn't lift off north of PGAS.

High contrast noaa bathy map to highlight shallow water depth.

« Last Edit: July 17, 2020, 11:10:24 AM by uniquorn »

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Re: Arctic Ocean salinity, temperature and waves
« Reply #638 on: July 17, 2020, 11:12:51 AM »
I think the ice is bouncing and sliding off PGAS because of the general direction of movement of the pack and because of the "inner elbow" where the ice must make a right turn. If this movement keeps up, there will be a lift off from PGAS as well.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #639 on: July 17, 2020, 11:22:04 AM »
I was hoping for another cloud free day in the Lincoln to have two days, but isn't happening.  Just happy to have the full suite of RAMMB imagery updating.
 Here's Lincoln see with heavy contrast.  I see two possible areas of upwelling.  Normally, I'm used to cooler water being upwelled, as that's what happens outside of the arctic.  One is in the upper left, the other is near the mouth of the first fjord up from the Nares entrance.  I also see a slight daily rhythm in the opening, I'm attributing to the sun. 
Needs a click
"To defy the laws of tradition, is a crusade only of the brave" - Les Claypool

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #640 on: July 17, 2020, 01:26:51 PM »
I think this area might tell us something

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #641 on: July 17, 2020, 05:30:27 PM »
Not really bouncing. Two points of interest here, the large lift off and the smaller floe (marked) drifting in a different direction

added large rammb, jul13-17
« Last Edit: July 17, 2020, 09:21:21 PM by uniquorn »

oren

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Re: Arctic Ocean salinity, temperature and waves
« Reply #642 on: July 18, 2020, 10:59:21 AM »
Thanks, very interesting.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #643 on: July 18, 2020, 03:47:37 PM »
IF there's any merit in the idea that the lift off is caused by internal waves reflected back from Laptev then as they move towards Greenland/Ellesmere they, at an atomic level, should acquire rotational energy as they move away from the pole/axis, thus where the coastline opens up that energy should penetrate deep into, for instance, the PGAS before emerging as turbulence/melt or simply added inertia through the channels. I'm thinking the rotation is acw/ccw and when it hits the coast the energy accelerates into the point of contact, and here cross hatching occurs and it's these raised features which move the ice from the coast, coupled with enhanced 'ice shelf' erosion. The initial wave motion may be spent in the upwelling but the rotational fraction will continue to build as the front moves south towards Banks Is.. I wonder too if the wave seperates as indicated by the bathymetry, and whether the movement of the fast ice, and the previously grounded 'foot' of the Splaltegletscher, north of 79N are a consequence? if so then Atl. penetration is going to ramp up change rather quickly.

oren

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Re: Arctic Ocean salinity, temperature and waves
« Reply #644 on: July 18, 2020, 04:51:56 PM »
John, why assume internal waves as the reason, if the sustained anti-cyclone wind provides a good enough and quite obvious explanation?

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #645 on: July 18, 2020, 08:52:10 PM »
If the explanation is obvious, why no lift off from pgas? And no bounce, which probably wasn't obvious. edit: maybe ossifrage has an explanation.

Posting a rough amsr2 overlaid onto mercator (model) 34m salinity while I attempt to work through some suggested presentation improvements. jun1-jul17
scales are probably meaningless with the overlay. red salinity>yellow>green>blue

Laptev modelled diluting or mixing the salty atlantic finger.
« Last Edit: July 18, 2020, 09:23:26 PM by uniquorn »

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Re: Arctic Ocean salinity, temperature and waves
« Reply #646 on: July 18, 2020, 09:28:40 PM »
Toggling between the last available frame from I4 and I2 bands. Trying to show, what I suspect is, Lena discharge extending into the Laptev.
Needs click
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oren

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Re: Arctic Ocean salinity, temperature and waves
« Reply #647 on: July 18, 2020, 09:55:11 PM »
If the explanation is obvious, why no lift off from pgas? And no bounce, which probably wasn't obvious. edit: maybe ossifrage has an explanation.

Posting a rough amsr2 overlaid onto mercator (model) 34m salinity while I attempt to work through some suggested presentation improvements. jun1-jul17
scales are probably eaningless with the overlay. red salinity>yellow>green>blue

Laptev modelled diluting or mixing the salty atlantic finger.
Uniquorn, I don't mean the explanation is "obvious obvious", just that the lift off in general was due to the anti-cyclonic winds according to my understanding. Why no lift-off from PGAS I do not know, but internal waves reflected from Laptev (as John proposed) sounds like a rather far-fetched explanation to my layman ears. Admittedly my knowledge is severely limited, so I'll try to keep an open mind and learn from my betters here.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #648 on: July 18, 2020, 11:11:15 PM »
Admittedly my knowledge is severely limited, so I'll try to keep an open mind and learn from my betters here.
Me too

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Re: Arctic Ocean salinity, temperature and waves
« Reply #649 on: July 18, 2020, 11:14:51 PM »
Toggling between the last available frame from I4 and I2 bands. Trying to show, what I suspect is, Lena discharge extending into the Laptev.
Needs click
To verify that I think you need to go back further and show the flow. Otherwise I think it is probably insolation on open water. Separated stills might be enough.