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Thibault Guinaldo

@tguinaldo.bsky.social

4.9K followers 1.2K following 450 posts

Ocean/climate. Research scientist #CNRM @meteofrance working on observations from #satellites (marine heatwaves, ocean color). Cyclist enthusiastic from the Pyrénées, climate refugee in Brittany back in Toulouse

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Thibault Guinaldo @tguinaldo.bsky.social · Apr 16

🌊 The N.Atlantic has been experiencing extreme T°C in 2023. This situation raises a number of questions: Have we missed something? Do climate models allow us to understand such an event, or have we entered a new climate regime?
We attempted to answer these questions in this study:
rdcu.be/eh0e8
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Internal variability effect doped by climate change drove the 2023 marine heat extreme in the North Atlantic

Communications Earth & Environment - The 2023 North Atlantic marine heatwave was driven by an extreme phase of internal atmospheric variability but would have been impossible without the doping...

rdcu.be

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Thibault Guinaldo @tguinaldo.bsky.social · 6h

Nouvelle étude utilisant des ensembles confirmant notre étude. La MHW subit par l'Atl.N en 2023 est un événement décennal soit rare mais pas inattendu en climat actuel.
Bien sûr, le principal moteur de ces extrêmes est le CC anthropique avec un modulation par la var.interne

tinyurl.com/2rtrbvne

Recent European marine heatwaves are unprecedented but not unexpected - Communications Earth & Environment

The unprecedented June 2023 marine heatwave in north-western Europe had a 10% annual likelihood, with climate change accelerating the risk of similar events, according to ensemble climate model simulations.

tinyurl.com

Reposted by Thibault Guinaldo

Francois Jobard @francoisjobard.bsky.social · 1d

🌀Je crois que c'est la première fois que je vois ça : l'agence météorologique espagnole nomme non pas un minimum dépressionnaire en Pmer, mais baptise de façon explicite une goutte froide d'altitude (ou dana, ou cutt-off low) en raison de probables futures intempéries pluvieuses : "la dana" #Alice.

carte anotée d'anomalie de géopotentiel à 500 hPa, issue du site d'Alicia Bentley, https://www.atmos.albany.edu/student/abentley/realtime/anom.php?domain=europe&variable=500g_anom

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Reposted by Thibault Guinaldo

Florence Habets @florencehabets.bsky.social · 4d

Lien alimentation-santé- environnement:
L'étude "Eat-Lancet » établit que les systèmes alimentaires sont un facteur majeur de dégradation de l’environnement et de hausse des maladies chroniques et des inégalités. Elle suggère à la fois un régime moins carné et un meilleur partage de la valeur"⤵️

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Reposted by Thibault Guinaldo

Florence Habets @florencehabets.bsky.social · 6d

Chaque année, 1500 km2 de nature et de terres agricoles disparaissent sous les constructions humaines en Europe
"On pourrait croire que l’artificialisation est d’abord tirée par la croissance démographique. Mais, en Europe le principal moteur est la richesse"
Merci @raphaelleaubert.bsky.social

Près de 50 m² de nature détruits chaque seconde : visualisez le bétonnage à grande échelle de l’Europe

Hangars, usines géantes, villas… Pixel après pixel, l’analyse inédite d’images aériennes de notre enquête « Green to Grey » dévoile les causes et l’ampleur de l’artificialisation qui transforme le con...

www.lemonde.fr

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Reposted by Thibault Guinaldo

Nikola Besic @nikobesic.bsky.social · 11d

Multiple models, one forest: a Bayesian perspective.

Led by Nicolas Picard, we combined climate-sensitive forest models to see where they agree - and where they don’t.

A better way to predict European beech’s future in a changing climate.

Read more 👉 authors.elsevier.com/c/1lrB815DJ-...

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Reposted by Thibault Guinaldo

Aurélien Bigo @aurelienbigo.bsky.social · 18d

L'asso Expertises Climat vise à faire du lien entre chercheurs et médias pour améliorer le traitement des enjeux environnementaux.

Elle lance une campagne de crowdfunding pour raconter des solutions / initiatives dans les médias.

Pr en savoir + et/ou participer ⬇
www.helloasso.com/associations...

Racontons ce qui se construit. Pas seulement ce qui s’effondre

Financement participatif organisé par Expertises climat - Jusqu'au 8 octobre inclus, 1% for the Planet double vos dons

www.helloasso.com

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Thibault Guinaldo @tguinaldo.bsky.social · 13d

La Journée mondiale de la mer est aujourd'hui.
Pour l'occasion, un article grand public sur l'importance des océans dans le système climatique :

- une augmentation de l'acidité
- des extrêmes chauds + intenses et + chauds
- un niveau qui ↗️

Avec des conséquences désastreuses
👇
tinyurl.com/bdcmx2hb

L’océan face au changement climatique | Météo-France

En absorbant la chaleur, l'océan a un important effet modérateur sur le climat et ses changements. Il est aussi particulièrement vulnérable au réchauffement climatique global et à l'augmentation du co...

tinyurl.com

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Reposted by Thibault Guinaldo

OCEAN ICE @oceaniceeu.bsky.social · 14d

❓Have you registered for the #ClimateCoffee on Ocean Heat Content (OHC), which is a key indicator of climate change?

✅No worries if you haven't, Register here:
www.eventbrite.dk/e/...

@MAIAresilience

👥See you on 22 May 2025 | 10:00 - 10:45 CEST

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Thibault Guinaldo @tguinaldo.bsky.social · 16d

Attendu ce matin : "avec les T°C de la Méditerranée, nous nous attendions à des événements de ce type jusqu'à la fin de l'année".
Oui les SSTs amplifient les evts pluvieux en Med, en ce moment +2/+3°C MAIS c'est bien l'instabilité atmosphérique qui pilote. Prévision impossible à long terme.

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Thibault Guinaldo @tguinaldo.bsky.social · 16d

However, I agree with you, we do not know (yet?) why this event lasted so long and what the probability is over the total duration.
By the way, I’m not downplaying the role of aerosols (sulphur, dust, …), I'm just surprised at how this narrative has been imposed, hidding other main factors

Thibault Guinaldo @tguinaldo.bsky.social · 16d

Thanks for your detailed and interesting/informative thread.
I’ll simply answer that we looked at this event compared to the 19th century and found this is a 1-in-10 year event or 1-in-100 event dependent on the region. This is a rare but plausible/excepted event at current global warming level

Reposted by Thibault Guinaldo

Peter Gleick @petergleick.bsky.social · 16d

The concept of trying to implement geoengineering solutions to #climate change is like trying to design a complicated, expensive, unreliable helmet while you're still hitting yourself in the head with a 2x4.

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Thibault Guinaldo @tguinaldo.bsky.social · 17d

You avoid most of comment… stratification driven by anthropogenic emissions is not short-lived…
On the other hand I gave you papers attributing extreme SSTs to IV+CC (and showing negligible IMO2020 effect), did you have one attributing them to IMO2020?

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Thibault Guinaldo @tguinaldo.bsky.social · 17d

My point is that communicator or geo-engineering enthusiast are not doing science but using strawman argument. As scientist we have to be rigourous. Knowing the time response of IMO2020, the real game changer is stratif which has a large scale and profound impact on heat content and ocean response.

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Thibault Guinaldo @tguinaldo.bsky.social · 17d

Yes IMO2020 has a negligible impact, Matt’s paper is clear on that plus this one : agupubs.onlinelibrary.wiley.com/doi/10.1029/...

Everyone should be careful in pointing out processes that are part of a climate response rather than a climate forcings.

agupubs.onlinelibrary.wiley.com

Thibault Guinaldo @tguinaldo.bsky.social · 17d

There is definitely a need for studying imbalance but coïncidence is not science.
5 articles were published in 2025 on SST in the N. Atlantic or globally, and all showed that this was driven by IV + CC. For me, stratification is a game changer and not a coincidence.

Thibault Guinaldo @tguinaldo.bsky.social · 17d

I’m sure you already the paper from Matt which has the same conclusions. This story is a defeat of science against communicators…

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Thibault Guinaldo @tguinaldo.bsky.social · 17d

Simulate a decennial event with couples models (with aérosols reductions taken into account in SSPs) are more solid evidence than a correlation between two maps

Thibault Guinaldo @tguinaldo.bsky.social · 17d

For N.Atlantic, IMO2020 cannot explain this rise, it is a combination of internal variability, long term warming and stratification :

www.nature.com/articles/s43...

Let’s study this event first (like it was done for he Blob) before pointing out IMO2020 solely with correlation between maps

Internal variability effect doped by climate change drove the 2023 marine heat extreme in the North Atlantic - Communications Earth & Environment

The 2023 North Atlantic marine heatwave was driven by an extreme phase of internal atmospheric variability but would have been impossible without the doping effect of anthropogenic warming, according ...

www.nature.com

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Reposted by Thibault Guinaldo

Zack Labe @zacklabe.com · 26d

The massive extreme marine heatwave continues to stretch across the entire northern Pacific Ocean. In fact, the magnitude of the sea surface temperature anomalies even grew in August 2025 compared to earlier in the summer. Yikes... 🫠

Data from OISSTv2.1 (psl.noaa.gov/data/gridded...). 🌊

Global map showing sea surface temperature anomalies in August 2025 relative to 1982 to 2010. Most areas are warmer than average. Red is shown for warmer sea surface temperatures, and blue is shown for colder sea surface temperatures. Data is from NOAA OISSTv2.1.

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Reposted by Thibault Guinaldo

Aida Alvera-Azcárate @aida-alvera.bsky.social · 28d

It's about time we start organizing the Liege Colloquium for 2026! Submesocale Processes in the ocean will be the topic, a revisit of the Colloquium of 2016. 10 years of advances!

I'll try to document here the journey towards organizing such an event, maybe there's interest? #LiegeOcean26 🌊🧪

Satellite image showing the ocean in shades of blue and green, with swirls and filaments. The land is in green. The image is located in the southeast coast of Norway, measured by Sentinel 2 on 19 May 2025

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Reposted by Thibault Guinaldo

Prof. Sonia I Seneviratne @soniaseneviratne.bsky.social · 28d

Hot off the press: We can provide for the first time a systematic attribution of recent #heatwaves to the emissions of #carbon_majors. Essential new #Nature article coordinated by @yannquilcaille.bsky.social at @ethz.ch, with numerous contributors @usyseth.bsky.social:
www.nature.com/articles/s41...

www.nature.com

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Audrey Garric @audreygarric.bsky.social · 29d

Rideaux géants dans l'océan, forage des calottes... Les projets de géoingénierie dans l’Arctique et l’Antarctique pour réduire l’impact du réchauffement climatique sont irréalisables et dangereux, préviennent 40 scientifiques dans une vaste revue de littérature
www.lemonde.fr/planete/arti...

Rideau géant dans l’océan, forage des calottes : des scientifiques dénoncent la dangerosité des projets de géoingénierie polaire

Plus de 40 scientifiques spécialistes des pôles publient, mardi, une évaluation critique de cinq procédés visant à manipuler l’Arctique et l’Antarctique afin d’atténuer les impacts du réchauffement cl...

www.lemonde.fr

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Reposted by Thibault Guinaldo

Andrew Dessler @andrewdessler.com · 27d

I've been getting requests from reporters about the disbanding of the DOE Climate Working Group. Here are some comments. More to come on my Substack (www.theclimatebrink.com).

The DOE Climate Working Group report was an absolute disaster from the beginning. It was created in secret with a hand-picked group of contrarians who do not represent any legitimate scientific position. The report ignored 99% of the scientific literature while employing selective data presentation, misrepresentation of scientific studies, misinterpretation of established science, speculative reasoning, and unsupported assumptions. Additionally, the group was clearly unprepared to meaningfully address the substantive critiques raised during the comment period.

This disastrous episode should put to rest proposals for adversarial "red team-blue team" exercises in climate science. The field already undergoes extraordinary scrutiny and replication, making it among the most thoroughly validated scientific disciplines. While uncertainties exist in climate science, they are well-characterized and constrained—and these remaining uncertainties do not undermine the core findings that climate

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Reposted by Thibault Guinaldo

Météo-France Ouest @meteofrance-o.bsky.social · Sep 1

🌊 Le saviez-vous ? Le Centre Marine & Offshore de Brest propose un stage à propos de la météo marine.

S'adressant à un public large, cette formation vise à rendre plus autonome sur l'analyse des conditions en mer.

ℹ️ + d'informations : services.meteofrance.com/formations-et-stages/navistages

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