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rolandseferian.bsky.social
Roland Séférian
@rolandseferian.bsky.social
3.4K followers 160 following 14 posts
climate scientist at #CNRM @meteofrance
| focus on #CarbonCycle & its iterations with climate | @IPCC_CH SR15 & AR7 | @esm2025.bsky.social
Posts Replies Media Videos
rolandseferian.bsky.social
Sad and happy at the same time !
Sad to see this adventure coming to an end.
Happy to see how much we achieved and how influential this project has been.
To the team, colleagues, and friends: thank you so much for these 4.5 years!
esm2025.bsky.social ESM2025 @esm2025.bsky.social · 1d
Today, ESM2025 officially comes to an end!

Since 2021, our European consortium has been building a new generation of Earth System Models to support mitigation & adaptation strategies aligned with the Paris Agreement. Watch these clips of our final video to see how far we've come!
🧵👇

#ESM2025isOver
November 30, 2025 at 6:42 PM
rolandseferian.bsky.social
Timely research highlight on land-based carbon dioxide removal approches developped by a great team !
esm2025.bsky.social ESM2025 @esm2025.bsky.social · 10d
Check out our latest highlight on how we worked on the assessment of climate impacts of land-based CDR across three angles:
🔄Carbon cycle changes
🌳Impacts on local climate, agriculture and hydrology
📉The Socio-economic dimension: uncertainty and risks
👉bit.ly/4qMYPEy

#ESM2025research
November 21, 2025 at 5:15 PM
Reposted by Roland Séférian
docaharper.bsky.social
Excellent summary of the work I contributed to in @esm2025.bsky.social, an EU-funded project that ends this year. Here are my key take-aways in a 🧵 , but I recommend reading this Research Highlight if you want to know more!
Several papers are in preparation from this work, so stay tuned.
esm2025.bsky.social ESM2025 @esm2025.bsky.social · 13d
Can we really count on land to deliver climate mitigation?

Our new highlight unpacks what AR/BECCS can do — and where uncertainties bite (carbon stocks, permanence, local climate effects).

Full story → bit.ly/4qMYPEy

#CDR #ESM2025research
@euclimateaction.bsky.social
November 19, 2025 at 2:52 PM
Reposted by Roland Séférian
soniaseneviratne.bsky.social
New starter pack with @ipcc.bsky.social #AR7 scientists (bureau, authors, REs)! Full list: apps.ipcc.ch/report/autho...
For SR cities scientists see separate starter pack!
@dianaurge.bsky.social @sherilee.bsky.social @siir-kilkis.bsky.social @janfuglestvedt.bsky.social
go.bsky.app/2FuXb3Y
September 6, 2025 at 2:37 PM
Reposted by Roland Séférian
philippequirion.bsky.social
www.hautconseilclimat.fr/actualites/o...
Objectif climatique européen 2040 et COP 30 : une proposition de la France menace l’Accord de Paris — Haut Conseil pour le Climat
Paris, le 5 septembre 2025 – Au moment des négociations européennes sur les objectifs climatiques de l’Union européenne pour la […]
www.hautconseilclimat.fr
September 5, 2025 at 5:21 PM
Reposted by Roland Séférian
lemonde.fr
Valérie Masson-Delmotte : « La situation climatique va encore empirer, mais le danger vient aussi d’un déni collectif »
Valérie Masson-Delmotte : « La situation climatique va encore empirer, mais le danger vient aussi d’un déni collectif »
Après un été marqué les incendies et la canicule, la climatologue, membre du Haut Conseil pour le climat, redoute un oubli rapide par la population, et regrette le manque de responsabilité du personnel politique.
www.lemonde.fr
August 25, 2025 at 11:33 AM
Reposted by Roland Séférian
ipcc.bsky.social
The #IPCC has announced the authors selected for its Seventh Assessment Report.

664 experts from 111 countries have been invited to participate as Coordinating Lead Authors, Lead Authors, & Review Editors.

🌍 51% from developing countries
🚺 46% women

🔗 bit.ly/AR7AuthorsPR
August 18, 2025 at 1:09 PM
Reposted by Roland Séférian
cassouman40.bsky.social
Un jour historique!

La CIJ: "Pour garantir la jouissance effective des droits de l’homme, les États doivent prendre des mesures pour protéger le syst. climatique & d’autres composantes de l’environnement"

Les pétitionnaires #LoiDuplomb ne demandent rien d'autre!
www.lemonde.fr/planete/arti...
La « violation » des obligations climatiques par un Etat constitue « un fait internationalement illicite engageant sa responsabilité », déclare la CIJ dans un avis historique
La Cour internationale de justice, la plus haute juridiction de l’ONU, rend un avis très attendu sur les obligations légales des Etats concernant le changement climatique.
www.lemonde.fr
July 23, 2025 at 5:11 PM
Reposted by Roland Séférian
bonpote.com
1.8 millions de signatures, et si le rythme reste le même, ce sera 2 millions avant demain soir. C'est historique. En plein été !

Chaque like, chaque partage, chaque signature compte.
Lien vers la pétition : petitions.assemblee-nationale.fr/initiatives/...
July 23, 2025 at 2:16 PM
Reposted by Roland Séférian
smlmrn.bsky.social
#EUBURN is an ambitious research program coordinated by @cyrielledenjean.bsky.social at #CNRM @meteofrance.com @cnrs.fr on #fire properties & atmospheric effects from in-situ aircraft & ground-based measurements, remote sensing & modeling approaches.
1st field campaign underway euburn.aeris-data.fr
July 20, 2025 at 8:44 AM
Reposted by Roland Séférian
bonpote.com
400 000 signatures dont 100 000 en 5h 🤯

Dernière ligne droite. Chaque like, chaque partage, chaque signature compte.

L’objectif des 500 000 signatures est possible d’ici dimanche soir, afin d’obtenir un vrai débat à l’Assemblée nationale sur la loi Duplomb.
July 19, 2025 at 10:02 AM
Reposted by Roland Séférian
wolfgangcramer.net
Ceci est une pétition d'une importance exceptionnelle pour la santé publique, l'environnement et même la démocratie. Je vous invite tous à la signer :

"Non à la Loi Duplomb — Pour la santé, la sécurité, l’intelligence collective"

>118000 dèjà

petitions.assemblee-nationale.fr/initiatives/...
logo du site des petitions
July 17, 2025 at 8:22 PM
Reposted by Roland Séférian
meteofrance.com
#JournéeMondialeDesOcéans |

🌊 Sur l’ensemble des #océans, la fréquence des canicules marines a doublé depuis 1982, et leur intensité augmente.

🌐 Dans le futur, elles seront 20 fois plus fréquentes avec un réchauffement de 2 °C.

www.youtube.com/watch?v=g54i...
Que fait Météo-France pour surveiller les canicules marines ?
YouTube video by METEO FRANCE
www.youtube.com
June 8, 2025 at 7:23 AM
Reposted by Roland Séférian
davidho.bsky.social
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."
May 4, 2025 at 6:21 AM
Reposted by Roland Séférian
davidho.bsky.social
More about threats to NOAA/GFDL.
White House Proposal Could Gut Climate Modeling the World Depends On
Potential funding cuts for NOAA and its research partners threaten irreparable harm not only to climate research but to American safety, competitiveness, and national security.
www.propublica.org
May 2, 2025 at 7:38 AM
Reposted by Roland Séférian
tatianailyina.bsky.social
On this sunny pre- #EGU25 day @chrisd-jones.bsky.social @pfriedling.bsky.social @rolandseferian.bsky.social and me, with colleagues will continue the effort to assess the Transient Climate Response to cumulative carbon Emissions (TCRE):
www.wcrp-climate.org/slc-events-o...
@wcrpclimate.bsky.social
Assessing the Transient Climate Response to Emissions (TCRE) and Zero Emissions Commitment (ZEC) Workshop 2025
Assessing the Transient Climate Response to Emissions (TCRE) and Zero Emissions Commitment (ZEC) Workshop 2025
www.wcrp-climate.org
April 27, 2025 at 6:52 AM
Reposted by Roland Séférian
magalireghezza.bsky.social
L'extrême-droite n’est pas climatosceptique et dit vouloir agir pour le climat.

L’extrême droite et ses alliés déposent un amendement pour supprimer le Haut Conseil pour le Climat.

Une de ces deux affirmations est fausse.

bonpote.com/lextreme-dro...
L'extrême droite dépose un amendement pour supprimer le Haut Conseil pour le Climat
Le Haut conseil pour le climat (HCC) est un organisme indépendant chargé d’évaluer l’action publique en matière de climat, et sa
bonpote.com
April 9, 2025 at 3:01 PM
Reposted by Roland Séférian
valmasdel.bsky.social
"many marine-climate interventions are currently being tested and deployed in an under-regulated pseudo-scientific bubble"

www.nature.com/articles/s41...
Novel marine-climate interventions hampered by low consensus and governance preparedness - Nature Climate Change
Oceans are on the front line of new planned climate actions, but understanding of novel marine-climate intervention development and deployment remains low. Here a survey among intervention practitione...
www.nature.com
April 5, 2025 at 7:03 AM
Reposted by Roland Séférian
sherilee.bsky.social
Important IPCC Session!

It will be critical for IPCC AR7 to meaningfully and ethically engage with Indigenous Knowledges.

Join our session co-hosted by @ipcc.bsky.social, Inuit Circumpolar Council, and Assembly of First Nations.

Registration links in thread below...
March 31, 2025 at 3:49 PM
Reposted by Roland Séférian
tguinaldo.bsky.social
Aujourd'hui est un jour spécial puisqu'à eu lieu la réunion de lancement du projet @agencerecherche.bsky.social Jeune Chercheur SAMOUSSA.
Ce projet basé au CNRM (@meteofrance.com @cnrs.fr) en collaboration avec le LEGOS (@ird-fr.bsky.social) porte sur un meilleur suivi et compréhension des Sargasses
Diaporama de présentation du projet ANR SAMOUSSA présenté le 27/03/2025
March 27, 2025 at 5:11 PM
Reposted by Roland Séférian
goneri76.bsky.social
Il me semble que nous pouvons déjà tirer quelques leçons en 🇨🇵🇪🇺 de ce qu'il se passe aux 🇺🇲 actuellement:
1. Il n'y a aucune raison de croire que des partis qui se sont construits sur la haine de la démocratie, de l'état de droit et de la diversité gouvernent en conservateurs modérés une fois élus.
March 22, 2025 at 7:12 PM
Reposted by Roland Séférian
agu.org
🚨Calling U.S.-based climate experts! The newly formed U.S. Academic Alliance for the @ipcc.bsky.social is now accepting nominations for the Seventh Assessment Report.🌍

Join a global network of scientists shaping the future of climate action.

Apply by April 4: buff.ly/hDrBH1F

#IPCC #AGU
buff.ly
March 20, 2025 at 12:05 PM
Reposted by Roland Séférian
jksteinberger.bsky.social
I really don't think this news has made sufficient shock waves.
Dr Katherine Calvin, NASA Chief Scientist Trump-Musk just fired, is the highest ranking American on the Intergovernmental Panel on Climate Change, the IPCC. She is co-chair of Working Group 3 on mitigation. This is a climate attack.
science.org Science Magazine @science.org · Mar 10
Breaking news: NASA announced today it will eliminate its Office of the Chief Scientist, along with offices advising the agency on technology, strategy, and coordinating its diversity, equity, inclusion, and accessibility efforts. scim.ag/3Ft8Xza
NASA to eliminate chief scientist position
Long-running advisory role cut along with two dozen others in agencywide reduction
scim.ag
March 15, 2025 at 3:11 PM
Reposted by Roland Séférian
pierregentine.bsky.social
www.nytimes.com/2025/03/07/n... - Columbia is being dramatically cut and I hope that the place I have called home for 15 years with many fantastic colleagues will survive this attack - it is clearly not related to antisemitism but Columbia had been defined as the number one target in academia
Trump Administration Cancels $400 Million in Federal Funds to Columbia University
The Trump administration blamed the university’s failure to protect Jewish students from harassment during protests last year over the war in Gaza.
www.nytimes.com
March 8, 2025 at 8:16 AM
Reposted by Roland Séférian
glenpeters.bsky.social
📢Global Carbon Budget 2024📢

Despite some predicting a peak in global fossil CO2 emissions, we estimate growth of 0.8% [-0.3% to 1.9%] in 2024. Maybe a peak next year?

Is it all bad news, or can we find some good news?

essd.copernicus.org/preprints/es...

1/
November 13, 2024 at 7:15 AM