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@micheltsamados.bsky.social

300 followers 350 following 99 posts

Physicist, Associate Professor at CPOM, @ES_UCL. Study climate of polar regions. Also dynamics of complex systems. Main current interest : sea ice. https://www.ucl.ac.uk/earth-sciences/people/academic/dr-michel-tsamados

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Environmental science 35%

Geology 32%

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micheltsamados.bsky.social @micheltsamados.bsky.social · Dec 5

Check the short video of our project put together by the amazing #CINUK team and explaining the project here youtu.be/JKyvfs06T-4 @es-ucl.bsky.social

Sikuttiaq: Sea ice travel safety, Inuit Qaujimajatuqangit, sea ice monitoring | CINUK

YouTube video by British Antarctic Survey

youtu.be

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micheltsamados.bsky.social @micheltsamados.bsky.social · 1d

😂

micheltsamados.bsky.social @micheltsamados.bsky.social · 5d

I wrote a post (with ChatGPT's help) on my stepdad's mathematical theories. Interested to hear your thoughts... www.linkedin.com/posts/michel...

Here’s a provocative take I’d love your reactions to 👇 What if the “laws of physics” aren’t out there in nature at all—but are programs our brains run, written by evolution to keep organisms… | Mich...

www.linkedin.com

micheltsamados.bsky.social @micheltsamados.bsky.social · 7d

Conflict of interest disclaimer: JL Krivine happens to be my step-dad ❤️

micheltsamados.bsky.social @micheltsamados.bsky.social · 7d

Very thought provoking talk from a famous maths professor Jean-Louis Krivine with a possible explanation of the paradoxes of physics, the Curry–Howard correspondence, the brain and much more...Physicist friends and colleagues buckle up! English subtitles available

www.youtube.com/watch?app=de...

P&M, Jean-Louis Krivine - La correspondance preuves-programmes : une découverte capitale et ignorée

YouTube video by Archive Trust for Research

www.youtube.com

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Reposted by Doerthe Tetzlaff, Mattias Hallquist, Christoph Scherber , and 2 more Doerthe Tetzlaff, Mattias Hallquist, Christoph Scherber, Juan Cole, Michel Tsamados

Prof. Stefan Rahmstorf @rahmstorf.bsky.social · Aug 30

Wow. Check this out.
Politicians actually trying to solve problems can achieve a lot!
www.washingtonpost.com/climate-solu...

Paris said au revoir to cars. Air pollution maps reveal a dramatic change.

Air pollution fell substantially as the city restricted car traffic and made way for parks and bike lanes.

www.washingtonpost.com

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Reposted by S. J. Holmes, Michel Tsamados

David Ho @davidho.bsky.social · Aug 29

Let me rewatch The Day After Tomorrow to see what to expect.

Collapse of critical Atlantic current is no longer low-likelihood, study finds

Scientists say ‘shocking’ discovery shows rapid cuts in carbon emissions are needed to avoid catastrophic fallout

www.theguardian.com

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micheltsamados.bsky.social @micheltsamados.bsky.social · Aug 26

Hi Alex you are onto something and couplings between ice-shelves and sea ice and ocean are important areas of research. I am afraid I can't tell you anything in more detail.

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micheltsamados.bsky.social @micheltsamados.bsky.social · Aug 26

To sum up, I wouldn't call this a good news story as the recent slow down of sea ice extent is only one part of a complex Arctic landscape (ice volume, ecology, temperature). I also don't think that we can draw any confident projections that the current slow down will persist in the coming years.

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micheltsamados.bsky.social @micheltsamados.bsky.social · Aug 26

7/n In my experience (e.g. Gregory et al. 2020) sea ice is too thick in climate models and there are also issues with the feedback processes in both summer and winter in the models.

tc.copernicus.org/articles/16/...

Network connectivity between the winter Arctic Oscillation and summer sea ice in CMIP6 models and observations

Abstract. The indirect effect of winter Arctic Oscillation (AO) events on the following summer Arctic sea ice extent suggests an inherent winter-to-summer mechanism for sea ice predictability. On the ...

tc.copernicus.org

micheltsamados.bsky.social @micheltsamados.bsky.social · Aug 26

6/n Another aspect of the study that is lacking some discussion and would be very interesting to investigate more is the so called 'model response uncertainty'. In other words how much of the model trends are due to deficiencies and biases in the models iopscience.iop.org/article/10.1...

Figure 3. Fractional contribution of model structure, emissions scenario, and internal variability to total uncertainty for percent of remaining sea ice cover in July, August and September (JAS) for the Central Arctic, Siberian Marginal Seas (Kara Sea, Laptev Sea, East Siberian Sea), and North American Marginal Seas (Chukchi Sea, Beaufort Sea, Canadian Archipelago). The solid white lines indicate the borders between sources of uncertainty, while the transparent white shading around those lines is the range of this estimate based on different estimates of internal variability in the MMLEA. All panels are for five-year mean projections of percent of remaining Arctic sea-ice cover relative to 1995–2014.

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micheltsamados.bsky.social @micheltsamados.bsky.social · Aug 26

5/n The authors briefly address this by looking at a model results on sea ice thickness but don't dive deeper into how their results hold when looking at the total sea ice volume. Satellite data on sea ice thickness exist (e.g. Landy et al. 2022). www.nature.com/articles/s41...

A year-round satellite sea-ice thickness record from CryoSat-2 - Nature

Deep learning and numerical simulations of CryoSat-2 radar altimeter data are used to generate a pan-Arctic sea-ice thickness dataset for the Arctic melt period.

www.nature.com

micheltsamados.bsky.social @micheltsamados.bsky.social · Aug 26

4/n I think the study is good and sound but might hide some more nuanced aspects of sea ice decline. Sea ice extent is a simplistic metric that encompasses a complex 3D field into a 2D projection. Other metrics, such as sea ice age for example, paint an even more alarming picture.

micheltsamados.bsky.social @micheltsamados.bsky.social · Aug 26

3/n Similar pauses or hiatuses are natural in the climate system and were extensively scrutinised in the past in the context of global climate warming (see 1998-2013 period).

en.wikipedia.org/wiki/Global_...

micheltsamados.bsky.social @micheltsamados.bsky.social · Aug 26

2/n By contrasting model results and satellite observations over the 2005-2024 period this study documents clearly a 'slowdown' or 'pause' in Arctic sea ice extent (the area where sea ice fraction is above 15%).

micheltsamados.bsky.social @micheltsamados.bsky.social · Aug 26

1/n Some thoughts from me on the 'good news' story about slow down of Arctic sea ice decline that came out in the Guardian last week following a paper published in GRL

www.theguardian.com/environment/...

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Reposted by David Johnson, Michel Tsamados

Zack Labe @zacklabe.com · Aug 7

The extraordinary loss of August #Arctic sea ice thickness over the last four decades...

Data available at psc.apl.uw.edu/research/pro.... More info at climatedataguide.ucar.edu/climate-data...

Four polar stereographic maps showing Arctic sea ice thickness during August in 1985-1994, 1995-2004, 2005-2014, and 2015-2024. There is ice thinning in nearly all locations. Ice thickness ranges from 0 to 5 meters.

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Reposted by Michel Tsamados

Alex Lipp @alexlipp.github.io · Jul 31

eartharxiv.org/repository/v...
In our new preprint we describe in detail the software & workflows behind www.SewageMap.co.uk! One for the open environmental data nerds out there :) 💩 🧑‍💻 🏞️

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micheltsamados.bsky.social @micheltsamados.bsky.social · Jul 8

Horrendous decision to replace those lovely line judges that contribute to the spirit of #Wimbledon by a defective and inhuman robot AI system. Why don't we replace the empire and players too and commentators and ball boys and girls. Or just switch off our TV.

David Ho @davidho.bsky.social · May 4

I think a lot about what Carl Sagan said in one of his final interviews.

"WE'VE ARRANGED A society based on science and technology, in which nobody understands anything about science technology. And this combustible mixture of ignorance and power, sooner or later, is going to blow up in our faces. Who is running the science and technology in a democracy if the people don't know anything about it?"
"Science is more than a body of knowledge, it's a way of thinking. A way of skeptically interrogating the universe with a fine understanding of human fallibility. If we are not able to ask skeptical questions, to interrogate those who tell us that something is true, to be skeptical of those in authority, then we're up for grabs for the next charlatan, political or religious, who comes ambling along."

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micheltsamados.bsky.social @micheltsamados.bsky.social · Jun 27

Last but not least session for me at #LPS25 with Rosie Willatt from @es-ucl.bsky.social telling us about up future opportunities in polar earth observation and upcoming satellites 🛰

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micheltsamados.bsky.social @micheltsamados.bsky.social · Jun 26

Valentin Ludwig summarising our results from the SIN’XS Sea Ice-thickness product iNter-comparison eXerciSe #lps25 @es-ucl.bsky.social sinxs.noveltis.fr

micheltsamados.bsky.social @micheltsamados.bsky.social · Jun 26

Another amazing presentation on our Inuit led safe travel on sea ice projects by Randy Scharien #smartice #lps25

micheltsamados.bsky.social @micheltsamados.bsky.social · Jun 26

Great talk on our safe travel on sea ice projects in Inuit Nunangat by Neil Brubacher in collaboration with the amazing Inuit social enterprise #smartice #lps25 @neilbrub.bsky.social

micheltsamados.bsky.social @micheltsamados.bsky.social · Jun 26

Next GAIA: A Global, Multimodal, Multiscale Vision-Language Dataset for Remote Sensing Image Analysis Angelos Zavras, Dimitrios Michail, Xiao Xiang Zhu, Beg"um Demir, loannis Papoutsis from Orion lab and national Athens observatory and national technical university of Athens 🇬🇷 #lps25

micheltsamados.bsky.social @micheltsamados.bsky.social · Jun 26

Exciting session this morning on large langage models application to Earth Observations #lps25 with Solene Debuysere and Madleen Bultez first #DIVA #controlnet

micheltsamados.bsky.social @micheltsamados.bsky.social · Jun 26

Add to your list a near total absence of US scientists at international conferences.

Reposted by Michel Tsamados

Zack Labe @zacklabe.com · Jun 25

So far this week:

❌ SSMIS data halted (think sea ice, snow, hurricane, ice sheet monitoring, etc)
❌ climate[dot]gov removed and redirected to...
❌ NOAA Climate homepage, which was modified (e.g., removed Climate Stripes and Climate Ready Nation references)
❌ false bills to ex-probationary employees

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Reposted by Michel Tsamados

Zack Labe @zacklabe.com · Jun 25

The poor "Sea Ice Index" nsidc.org/data/seaice_... 😢

See thread for more on this tragic data loss: bsky.app/profile/zack...

Screenshot for the NSIDC Sea Ice Index, which says "This data set was recently downgraded to a “Basic” Level of Service. Learn more about what this means for users here" and "The Department of Defense (DoD) will stop processing and delivering the Special Sensor Microwave Imager/Sounder (SSMIS) data no later than 30 June 2025. The SSMIS data are used as input for this NSIDC-produced data set, which will therefore stop processing no later than 30 June 2025. Please contact NSIDC User Services if you have questions."

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Reposted by Ed Hawkins, John Fasullo, Michel Tsamados

EUMETSAT OSI SAF @osi-saf.eumetsat.int · Jun 25

🚧Urgent notice to all SSMIS product users 🚧

We've just been informed that #SSMIS from the US #DMSP satellite will stop to be distributed on Monday 30/06/2025.
Consequently, we advise SSMIS only-based #SeaIce products users to urgently change.

More information:
osi-saf.eumetsat.int/community/st...

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micheltsamados.bsky.social @micheltsamados.bsky.social · Jun 25

Great overview presentation by Sarah Kacimi on altimetry for sea ice retrievals and remaining challenges in both Arctic and Antarctic. Note the empty desk as the presentation had to be remote / recorded #lps25