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Evgenii Salganik

@salganik.bsky.social
74 followers 79 following 69 posts

ice researcher and architecture photographer Alfred Wegener Institute @awi.de

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Evgenii Salganik @salganik.bsky.social · 24/08/2026
Sea-ice density varies seasonally, but is still often treated as constant or ice-age dependent. Using hydrostatically weighed Arctic sea-ice cores, we develop a year-round parameterization based on temperature and thickness, plus snow/freeboard variants for remote sensing. doi.org/10.22541/ess...
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Evgenii Salganik @salganik.bsky.social · 30/04/2026
During MOSAiC, one spring biological sample was named “Ridgey McRidgeFace” — and it made it into the final paper (doi.org/10.1038/s43247-026-03364-8). RMRF was a young ridge of thin first-year ice sampled in late March. The real challenge? Explaining what RMRF actually stands for.
Snow freeboard maps from 10 May 2020 showing the Ridgey McRidgeFace (RMRF) ridge. From the larger Central Observatory (CO) area near RV Polarstern (left) to a detailed view of the ridge (right), including coring sites sampled in late April and early May.
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Evgenii Salganik @salganik.bsky.social · 13/04/2026
Our graphic shows Arctic sea-ice ridges aren’t just rubble—they’re biomass hotspots. In summer, they can hold up to ~80–100% of ice-algal biomass despite covering much less area. Their complex structure creates diverse microhabitats for microbial life. doi.org/10.1038/s432... 🎨 Frida Cnossen
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Evgenii Salganik @salganik.bsky.social · 09/04/2026
There are many colorblind-friendly, perceptually uniform colormaps (e.g., cmocean, @fabiocrameri.ch), yet many papers at @agu.org still use rainbow variants. Not just aesthetics — they can create artificial structures (see plot). Better options exist.
Two contour plots of continuous temperature measurements in sea ice, snow, air, and seawater (Hammer et al., 2026; doi:10.1029/2025JC022738), shown using a rainbow-style colormap.
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Evgenii Salganik @salganik.bsky.social · 04/03/2026
Some papers follow me into my nightmares. This study about the shape of pressure ridges claims that most of them are cusped (like an arrow tip). Not only is this counterintuitive, but when I checked the dataset used in the study, most ridges appeared to be either trapezoidal or irregular.
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Evgenii Salganik @salganik.bsky.social · 29/12/2025
Can a portable device measure the full thickness of sea-ice pressure ridges? New preprint led by Polona Itkin @oceanseaicenpi.bsky.social tests ground-based electromagnetic induction (GEM) across all seasons. doi.org/10.5194/egus...
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Evgenii Salganik @salganik.bsky.social · 04/12/2025
A blog post from Megan Lenss about our new paper on Antarctic sea-ice algae: ic3.uit.no/news/hidden-...
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Evgenii Salganik @salganik.bsky.social · 19/11/2025
New nice preprint led by Dmitry Divine (@oceanseaicenpi.bsky.social) on #Arctic sea ice ridge volume in the Fram Strait, derived from moored sonar observations from 2012–2019: doi.org/10.5194/egus...
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Evgenii Salganik @salganik.bsky.social · 29/09/2025
A new thesis about the inclusion of air bubbles into the mushy layer model of sea ice by Joseph Fishlock from the University of Oxford @ox.ac.uk: ora.ox.ac.uk/objects/uuid...
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Evgenii Salganik @salganik.bsky.social · 12/09/2025
Back from the CONTRASTS expedition (July–Sept)! We studied 3 types of Arctic sea ice, revisiting each site 4 times. I wrote a short overview here: en.wikipedia.org/wiki/CONTRAS...
en.wikipedia.org
CONTRASTS Expedition - Wikipedia
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Reposted by Evgenii Salganik
Alfred Wegener Institute @awi.de · 08/09/2025
Unique concept for observing Arctic sea ice successfully implemented: AWI scientists were able to study different types of sea ice in parallel during the Polarstern expedition “CONTRASTS.” 🧊 www.awi.de/en/about-us/... Photo: Evgenii Salganik
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Evgenii Salganik @salganik.bsky.social · 28/06/2025
Great to see a data paper from the Nansen Legacy cruises (2018–2022), led by Dmitry Divine (@oceanseaicenpi.bsky.social), including sea ice density measurements that clearly show strong seasonality: doi.org/10.1002/gdj3.70001
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Evgenii Salganik @salganik.bsky.social · 06/06/2025
Our new data paper about under-ice observations from a remotely operated vehicle (ROV) during MOSAiC led by Philipp Anhaus from @awi.de: www.nature.com/articles/s41...
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Evgenii Salganik @salganik.bsky.social · 08/05/2025
A new study led by Niels Fuchs uses hydrological models to predict the locations of melt ponds: doi.org/10.1029/2025GL115033
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Reposted by Evgenii Salganik
Marylou Athanase @marylouathanase.bsky.social · 31/03/2025
Our new study is out: The Arctic Beaufort Gyre is projected to weaken or vanish in most CMIP6 models under future climate change. The gyre would thus stop storing freshwater in its centre, with possibly large impacts on the Arctic and beyond. Read: agupubs.onlinelibrary.wiley.com/doi/full/10....
agupubs.onlinelibrary.wiley.com
The Arctic Beaufort Gyre in CMIP6 Models: Present and Future
CMIP6 models generally simulate a too strong, large, and northward-extending Beaufort Gyre (BG) during the historical period Among the least unrealistic models, most simulations project a decline...
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Evgenii Salganik @salganik.bsky.social · 29/03/2025
Ice Mass Balance (IMB) buoys are unique in their ability to distinguish between ice surface and bottom melt, which relates to the way solar energy is distributed. Models still do a poor job of capturing this. You can find the updated Wiki article here: en.wikipedia.org/wiki/Ice_mass_balance_buoy
Temporal evolution of temperature from Ice Mass Balance Buoy with identified interfaces of air, melt pond, first-year ice, seawater, and meltwater layer.
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Evgenii Salganik @salganik.bsky.social · 28/03/2025
If you are into Arctic sea ice thermodynamics, here is our new dataset of 82 CRREL ice mass balance buoys deployed in 1997–2024 with estimates of snow and ice thickness and their interface evolution: doi.org/10.5281/zenodo.15096485
Two panels show the temporal evolution of snow (top) and sea ice (bottom) thickness from various ice mass balance buoys listed in the legend (right).
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Evgenii Salganik @salganik.bsky.social · 21/03/2025
If you are into modeling of sea ice physical properties (salinity, brine volume, or density), we combined coring datasets to have a seasonal evolution for first- and second-year level ice: doi.org/10.5281/zeno... The coring datasets have many more parameters, including isotopes and nutrients.
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Evgenii Salganik @salganik.bsky.social · 18/03/2025
In summer we typically track sea ice melt, assuming its height above the waterline decreases. In our new study, we show that sea ice freeboard may increase during the advanced melt in June and July due to the rapid decrease of ice density. Read more: doi.org/10.5194/tc-19-1259-2025
Upper panel shows temporal decrease of ice density in June and July estmated using (1 ) ice weighing, (2) thickness coring, and (3) co-located freeboard and draft measurements from underwater sonar and airborne laser scanner.

Lower panel shows spatiotemporal variability of first-year ice density during the melt season.
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Evgenii Salganik @salganik.bsky.social · 28/02/2025
Last day at the Norwegian Polar Institute. Thanks for the good memories.
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Evgenii Salganik @salganik.bsky.social · 28/02/2025
Yesterday, you showed Zack's beautiful work to your colleague; today, he no longer works at NOAA. Huge support. We all live in an evolving dystopia.
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Evgenii Salganik @salganik.bsky.social · 19/02/2025
Shocking. It is hard to overestimate the importance of all the wonderful research and observations from NOAA @climate.noaa.gov and other US-based agencies. Huge support to Zack and others who are affected.
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Reposted by Evgenii Salganik
Oceans & Sea Ice NPI @oceanseaicenpi.bsky.social · 14/02/2025
Fate of #Arctic sea ice melt | In a new study led by @madm-ice.bsky.social, we followed the #MOSAiC ice floe and calculated the budget of freshwater sources and sinks from snow and ice melt in summer 2020. Read more: doi.org/10.5194/tc-19-619-2025
A researcher (Madison Smith) walking on sea ice covered by melt ponds. Photo by Evgenii Salganik.
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Evgenii Salganik @salganik.bsky.social · 04/02/2025
Impressive airborne measurements of ice ridge spacing led by Thomas Krumpen:
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Evgenii Salganik @salganik.bsky.social · 24/01/2025
Academic journals may need stricter guidelines for introductions. Broad overviews with ambiguous claims and irrelevant references are way too common. Worse, unjustified citations of colleagues and co-authors further devalue citations, as if they can get less valuable than now.
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Evgenii Salganik @salganik.bsky.social · 20/01/2025
If only they could have asked the author. The sea-ice density part is not much better. Half-based on a 1978 study published in Russian and not publicly available.
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Evgenii Salganik @salganik.bsky.social · 17/01/2025
The only problem with Fabio's color maps is that they are so beautiful it is hard to choose one.
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Evgenii Salganik @salganik.bsky.social · 13/01/2025
Our sea ice and ocean sections of Norwegian Polar Institute on Bluesky:
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Evgenii Salganik @salganik.bsky.social · 13/01/2025
Quote from WMO sea ice nomenclature: "Ice ridge concentration: Concentration (aerial coverage) of hummocked ice of all kinds in an ice area in tenths." Should it be areal instead of aerial? @wmo-global.bsky.social, we can do better.
Photo of a sea ice ridge with its keel draft measured by sonar and its sail freeboard measured by airborne laser scanner during the MOSAiC expedition.
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Evgenii Salganik @salganik.bsky.social · 07/01/2025
A great new study led by Thomas Krumpen about the decrease of ridge density based on airborne observations since the 1990s:
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Evgenii Salganik @salganik.bsky.social · 16/12/2024
Presenting our work on sea-ice ridge thermodynamics during winter and summer at @agu.org was a pleasure. You can check out our #AGU24 talk here: www.youtube.com/watch?v=gUFi...
youtube.com
Seasonal evolution of sea ice ridges presented at AGU24
YouTube video by Evgenii Salganik
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Evgenii Salganik @salganik.bsky.social · 10/09/2024
Our work with Odile Crabeck and Jack Landy about the rapid decrease of sea-ice density in summer leading to non-decreasing ice freeboard during 0.6 m ice thickness loss: doi.org/10.5194/egus...
On the left panel, we show a counterplot of sea-ice density evolution in summer decreasing from 912 to 880 kg/m³. On the ridge side, we show the temporal evolution of bulk sea-ice density measured in situ and estimated from ice freeboard and draft from coring, from airborne laser scanner, and underwater sonar.
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Evgenii Salganik @salganik.bsky.social · 22/08/2024
The ecosystem work overview of the MOSAiC expedition led by Allison Fong is published at Elementa: Science of the Anthropocene: doi.org/10.1525/elem...
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Evgenii Salganik @salganik.bsky.social · 26/02/2024
Great start of the MOSAiC conference in Potsdam with the team ocean work overview by @clnhz.bsky.social
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Evgenii Salganik @salganik.bsky.social · 01/02/2024
Sea ice cores from the MOSAiC expedition were finally CT-scanned at the European Synchrotron in Grenoble at their natural temperatures when they were collected during the 2019–20 season: www.esrf.fr/home/news/ge...
Research vessel Polarstern in sea ice during MOSAiC expedition
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Evgenii Salganik @salganik.bsky.social · 21/01/2024
First morning at European Synchrotron before scanning some MOSAiC sea ice with Sönke Maus from NTNU and Martin Schneebeli from @slfdavos.bsky.social
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Evgenii Salganik @salganik.bsky.social · 15/12/2023
Norwegian universities announced their tuition fees for non-EU students. The NTNU annual fee is €43,000 for medicine and €22,500 for technology. It is too high and not supported by educational quality or rankings. Which would mean there will be no non-EU students in Norway.
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Evgenii Salganik @salganik.bsky.social · 13/12/2023
If thicker ice melts faster, does it apply to pressure ridges? Ridge flanks also show a good 60% correlation between melt and draft. But for the ridge bottom part, the correlation is much weaker (only 20%), as its melt also depends on ridge width and slope.
The first image shows the frequancy of the measured by underwater sonar ice melt vs. its initial draft, with a 45% correlation between melt and draft. The second image shows an aerial image of the surveyed sea ice. The third image shows the spatial distribution of ice melt over the area of the sonar surveys.
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Evgenii Salganik @salganik.bsky.social · 11/12/2023
How often have you heard that thinner ice melts faster? Our measurements of ice melt from the Alfred Wegener Institute ROV underwater sonar show that it is quite the opposite, with a 45% correlation between first-year ice melt and its initial draft:
The first image shows the frequancy of the measured by underwater sonar ice melt vs. its initial draft, with a 45% correlation between melt and draft. The second image shows an aerial image of the surveyed sea ice. The third image shows the spatial distribution of ice melt over the area of the sonar surveys.
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Evgenii Salganik @salganik.bsky.social · 08/12/2023
One of my guilty pleasures is updating Wikipedia about my favorite topics. I like imperfect Wiki for being neutral by design, written by hundreds of authors with diverse worldviews, and looking like scientific papers, as everything should be referenced. This is from the page about false bottoms:
Scheme of false bottom formed under sea ice
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Evgenii Salganik @salganik.bsky.social · 24/11/2023
When sea ice melts, even after snow is gone, it looks like snow because of the meltwater drainage. In the new study by @madm-ice.bsky.social et al., they describe the albedo of this "surface scattering layer", how fast it can form from bare ice, and how it affects ice melt: doi.org/10.1029/2022...
Two scientists are walking on the Arctic sea ice covered by melt ponds during a scientific expedition.
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Evgenii Salganik @salganik.bsky.social · 23/11/2023
Arctic sea ice drifts around twice as fast during the summer (Olason and Notz, 2014). Its drift speed correlates with ice thickness at high ice concentrations. But during the summer, ice also loses its roughness as thicker ice melts faster (color map is from @fabiocrameri.ch):
Two images show sea-ice drafts on 24 June and 21 July, after one month of ice melt. Sea-ice became thinner and less rough as thicker ice (with a larger draft) melts faster than thinner ice.
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Evgenii Salganik @salganik.bsky.social · 22/11/2023
A single number is not enough to understand ridge melt enhancement. Some of our ridge cross-sections melted by only 0.2 m, while others by 2.6 m. So we also showed key characteristics defining ridge melt. Deeper, narrower, and steeper ridges melt faster. The largest melt occurs at the ridge corners.
The left figure shows the average cross-sectional profile of the ridge before and during its melt on 24 June and 21 July. The right figure shows a map of the spatial distribution of the sea-ice ridge melts. It also shows the locations of four corners of ridge cross-sections, assuming ridges are trapezoidal. Most of the melt occurs around two ridge bottom corners.
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Evgenii Salganik @salganik.bsky.social · 21/11/2023
Our new @eurogeosciences.bsky.social Cryosphere study shows strong differences in melt rates of the main sea-ice types using multibeam sonar surveys during the MOSAiC expedition, with a substantial enhancement of ridge melt: doi.org/10.5194/tc-1...
The left figure shows a map with sea ice draft (or how deep is the ice bottom under the waterline) and selected ice types, including undeformed first-, and second-year ice (FYI and SYI) and two ice ridges.

The right figure shows the evolution in time of average drafts of these four ice types, indicating, that the ridge is melting much faster than undeformed ice (both FYI and SYI).
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Evgenii Salganik @salganik.bsky.social · 03/11/2023
We compared Fram Strait sea-ice ridge shapes from ROV sonar with moored sonar measurements from Ekeberg et al. (2014). On average, we had a two-times wider bottom ridge width, covering 38% of the total width, yet 10% of cross-sections were absolutely not trapezoidal:
Comparison of sea-ice ridge cross-sectional shape
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Evgenii Salganik @salganik.bsky.social · 03/11/2023
Sea-ice ridges are often thought of as lines with trapezoidal cross-sections but in 3D they look quite more complex:
Bottom topography of sea-ice ridge
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