Tom Chalk
@chalkyoceans.bsky.social
Dr Chalk, destined to be a researcher of carbonates. CO2, & ocean-climate links, resident isotope geochemist @exoceanlab.bsky.social,
@cerege.bsky.social, France.
Equalist, technologist, environmentalist. #climatevegan 🌱.
🇬🇧🤝🇲🇫. 🏳️🌈 but always with the 🏳️⚧️.
@cerege.bsky.social, France.
Equalist, technologist, environmentalist. #climatevegan 🌱.
🇬🇧🤝🇲🇫. 🏳️🌈 but always with the 🏳️⚧️.
Reposted by Tom Chalk
#CNRSNews 📰 Scientists have set up standards for marine CO2 removal, which could enable extra oceanic storage of carbon dioxide and its recovery as carbonate or biomass. Yet further research is needed prior to large-scale implementation
Scooping out oceanic CO₂ to make room for more
news.cnrs.fr
January 12, 2026 at 7:37 PM
#CNRSNews 📰 Scientists have set up standards for marine CO2 removal, which could enable extra oceanic storage of carbon dioxide and its recovery as carbonate or biomass. Yet further research is needed prior to large-scale implementation
Reposted by Tom Chalk
#exocean advent calendar day 24!
Today we thought it was a good fit to show an image/talk about “conception”…
One of the thing we (try to) do best at ExoCean is planktonic foraminifera reproduction. Here two immaculate mummies… 😏
We would like to wish you all a beautiful Christmas Eve!
Today we thought it was a good fit to show an image/talk about “conception”…
One of the thing we (try to) do best at ExoCean is planktonic foraminifera reproduction. Here two immaculate mummies… 😏
We would like to wish you all a beautiful Christmas Eve!
December 24, 2025 at 1:34 PM
#exocean advent calendar day 24!
Today we thought it was a good fit to show an image/talk about “conception”…
One of the thing we (try to) do best at ExoCean is planktonic foraminifera reproduction. Here two immaculate mummies… 😏
We would like to wish you all a beautiful Christmas Eve!
Today we thought it was a good fit to show an image/talk about “conception”…
One of the thing we (try to) do best at ExoCean is planktonic foraminifera reproduction. Here two immaculate mummies… 😏
We would like to wish you all a beautiful Christmas Eve!
Reposted by Tom Chalk
#exoCeanadvent Day 23: at exoCean we also look at some old questions: in the late 1800s, during the HMS Challenger expedition, they discovered that you can have a constant rain of shells from above, and still end up with a seafloor that looks like the carbonate budget never existed. Why? Pressure. 🌊
December 23, 2025 at 6:21 PM
#exoCeanadvent Day 23: at exoCean we also look at some old questions: in the late 1800s, during the HMS Challenger expedition, they discovered that you can have a constant rain of shells from above, and still end up with a seafloor that looks like the carbonate budget never existed. Why? Pressure. 🌊
Reposted by Tom Chalk
More politicians, policymakers, and companies should be on Bluesky.
This has always been a Bluesky-first campaign. But as of today, we will no longer be using Twitter. At all.
And I'm calling on other candidates to follow suit.
And I'm calling on other candidates to follow suit.
December 22, 2025 at 6:15 PM
More politicians, policymakers, and companies should be on Bluesky.
Reposted by Tom Chalk
#exoCeanadvent Day 22: Winding down for the holidays often means one thing... more mass spectrometry time is available! With our friends in @cerege.bsky.social's #ENVITOP facility, we're making use! Thanks to their equipment we're working on measuring elemental compositions down to the nano-gramme!
December 22, 2025 at 4:28 PM
#exoCeanadvent Day 22: Winding down for the holidays often means one thing... more mass spectrometry time is available! With our friends in @cerege.bsky.social's #ENVITOP facility, we're making use! Thanks to their equipment we're working on measuring elemental compositions down to the nano-gramme!
Reposted by Tom Chalk
#exocean advent calendar Day 21! The strongest link between all of us is our love for the ocean. Leaving Marseille with a magnificent sunrise reminds us each time we go out how lucky we are to do what we love for a living!
We already have our ship time for the first 6 months of 2026 - exciting!
We already have our ship time for the first 6 months of 2026 - exciting!
December 21, 2025 at 7:13 PM
#exocean advent calendar Day 21! The strongest link between all of us is our love for the ocean. Leaving Marseille with a magnificent sunrise reminds us each time we go out how lucky we are to do what we love for a living!
We already have our ship time for the first 6 months of 2026 - exciting!
We already have our ship time for the first 6 months of 2026 - exciting!
Here's to #2026! Please don't hold us to any of these...
December 20, 2025 at 5:38 PM
Here's to #2026! Please don't hold us to any of these...
Reposted by Tom Chalk
12 scientific papers 💻, 11 months of good weather 🌞, 10⁴ foram babies 🐚, 9 visiting scientists 👩🏼🔬👨🏾🔬, 8 successful boat missions 🛥️, 7 website visits 🙏🏼, 6 new hypotheses 💡...*5 gold rings*...4 defended masters 📜, 3 #ForCry mass spec methods 🔍, 2 #Deep-C reactors 🧿...
December 20, 2025 at 5:35 PM
Reposted by Tom Chalk
#exoCeanadvent Day 19: Friday edition: today’s post is about the peacocks at CEREGE, because it’s Friday and our brains are in weekend mode. They wander around like they own the campus, scream for no reason, and block paths with absolute confidence. Honestly, goals. 🦚
December 19, 2025 at 6:00 PM
#exoCeanadvent Day 19: Friday edition: today’s post is about the peacocks at CEREGE, because it’s Friday and our brains are in weekend mode. They wander around like they own the campus, scream for no reason, and block paths with absolute confidence. Honestly, goals. 🦚
Essential reading for those interested in going carbon negative 👀. See what @sulpis.bsky.social does for a living and how it connects to @exoceanlab.bsky.social here!
Read the European Marine Board report here: 📘👀
www.marineboard.eu/publications...
www.marineboard.eu/publications...
Monitoring, Reporting and Verification for marine Carbon Dioxide Removal
Marine Carbon Dioxide Removal (mCDR) methods are being proposed and piloted in Europe. Monitoring, Reporting and Verification (MRV) is a structured process to collect, disclose and independently verif...
www.marineboard.eu
December 18, 2025 at 1:52 PM
Essential reading for those interested in going carbon negative 👀. See what @sulpis.bsky.social does for a living and how it connects to @exoceanlab.bsky.social here!
Reposted by Tom Chalk
Read the European Marine Board report here: 📘👀
www.marineboard.eu/publications...
www.marineboard.eu/publications...
Monitoring, Reporting and Verification for marine Carbon Dioxide Removal
Marine Carbon Dioxide Removal (mCDR) methods are being proposed and piloted in Europe. Monitoring, Reporting and Verification (MRV) is a structured process to collect, disclose and independently verif...
www.marineboard.eu
December 18, 2025 at 12:08 PM
Read the European Marine Board report here: 📘👀
www.marineboard.eu/publications...
www.marineboard.eu/publications...
Net accident you say? Ooops, this net came back looking like it had been mauled by a shark, and I think... Maybe it had. A good, but expensive(!) sample. Sorry @tdegaridel.bsky.social!
December 17, 2025 at 7:51 PM
Net accident you say? Ooops, this net came back looking like it had been mauled by a shark, and I think... Maybe it had. A good, but expensive(!) sample. Sorry @tdegaridel.bsky.social!
Reposted by Tom Chalk
#exoCeanadvent Day 16: We're getting closer to the holidays, but we don't stop yet. @erc.europa.eu postdoc @jysuarezibarra.bsky.social was out today presenting his work @maxplanck.de in Mainz. @soniachaabane.bsky.social is also visiting to chat with colleagues.
December 16, 2025 at 5:22 PM
#exoCeanadvent Day 16: We're getting closer to the holidays, but we don't stop yet. @erc.europa.eu postdoc @jysuarezibarra.bsky.social was out today presenting his work @maxplanck.de in Mainz. @soniachaabane.bsky.social is also visiting to chat with colleagues.
Reposted by Tom Chalk
#exoCeanadvent Day 15: Some plankton are tiny [citation needed?], and for those we need ways to measure tiny (this is a theme you'll hear us talking about a lot). Sometimes just holding samples in place can be hard.... enter the #Cryostage! ❄️
December 15, 2025 at 6:11 PM
#exoCeanadvent Day 15: Some plankton are tiny [citation needed?], and for those we need ways to measure tiny (this is a theme you'll hear us talking about a lot). Sometimes just holding samples in place can be hard.... enter the #Cryostage! ❄️
Reposted by Tom Chalk
#exoCeanadvent Day 14 Footprint reduction: we do lab-based ocean science because we genuinely love it, but also because lab experiments can replace lots of field trips. More control, more insight, and in part, fewer emissions. Bonus: dissolving old sediment cores neutralizes a bit of CO2. 😇
December 14, 2025 at 6:05 PM
#exoCeanadvent Day 14 Footprint reduction: we do lab-based ocean science because we genuinely love it, but also because lab experiments can replace lots of field trips. More control, more insight, and in part, fewer emissions. Bonus: dissolving old sediment cores neutralizes a bit of CO2. 😇
Reposted by Tom Chalk
#exoCeanadvent Day 13: Time Machine. Travel back in time with us 6 million years. Part of the reason for our work @exoceanlab.bsky.social is to better understand the past through observing the modern, but sometimes you just need some ancient mud..@chalkyoceans.bsky.social recently went to get some!
December 13, 2025 at 4:53 PM
#exoCeanadvent Day 13: Time Machine. Travel back in time with us 6 million years. Part of the reason for our work @exoceanlab.bsky.social is to better understand the past through observing the modern, but sometimes you just need some ancient mud..@chalkyoceans.bsky.social recently went to get some!
Reposted by Tom Chalk
#exoCeanadvent Day 12: End-of-year celebration - raclette edition. On the agenda for this team meeting: cheese, cheese, cheese, goals for next year: even more cheese. We’ve officially reached our melting point. 🧀
December 12, 2025 at 2:25 PM
#exoCeanadvent Day 12: End-of-year celebration - raclette edition. On the agenda for this team meeting: cheese, cheese, cheese, goals for next year: even more cheese. We’ve officially reached our melting point. 🧀
Reposted by Tom Chalk
#exoCeanadvent Day 11: Science makes you do strange things. Meet @astridhylen.bsky.social, a postdoc working with carbonate dissolution in coastal sediments. She recently found herself in the middle of a salt marsh, stirring one of the ponds with a (clean) toilet brush taped to a curtain rod.
December 11, 2025 at 6:27 PM
#exoCeanadvent Day 11: Science makes you do strange things. Meet @astridhylen.bsky.social, a postdoc working with carbonate dissolution in coastal sediments. She recently found herself in the middle of a salt marsh, stirring one of the ponds with a (clean) toilet brush taped to a curtain rod.
There's still much more to come from our trip to Bermuda with @juliemeilland.bsky.social, @thefosterlab.bsky.social and @case4climate.bsky.social. Whilst there, we were all tortured with video interviews... Here's a taster!
December 10, 2025 at 6:14 PM
There's still much more to come from our trip to Bermuda with @juliemeilland.bsky.social, @thefosterlab.bsky.social and @case4climate.bsky.social. Whilst there, we were all tortured with video interviews... Here's a taster!
100% recommend for fieldwork. See @maxime-felix.bsky.social for details on availability.
The results did not reveal significant trend among the treatments, suggesting that under the tested conditions, the addition of olivine did not appear to affect foraminifera biology. Good news!
Also, if anyone needs water filtration in the field with no electricity, Maxime is your guy.
Also, if anyone needs water filtration in the field with no electricity, Maxime is your guy.
December 9, 2025 at 4:57 PM
100% recommend for fieldwork. See @maxime-felix.bsky.social for details on availability.
Reposted by Tom Chalk
#exoCeanadvent Day 9: Meet Maxime (again). At @exoceanlab.bsky.social and @climatecerege.bsky.social Maxime has been conducting several experiments focusing on the culture of marine organisms. One project involved culturing foraminifera in the presence of olivine (Mg,Fe)2SiO4, an igneous mineral.
December 9, 2025 at 4:25 PM
#exoCeanadvent Day 9: Meet Maxime (again). At @exoceanlab.bsky.social and @climatecerege.bsky.social Maxime has been conducting several experiments focusing on the culture of marine organisms. One project involved culturing foraminifera in the presence of olivine (Mg,Fe)2SiO4, an igneous mineral.
One of many super cool projects started or starting in @exoceanlab.bsky.social. Keep it up Katoo!
#exoCeanadvent Day 8: Meet Katoo Declerk's Erasmus+ work. During her internship Katoo is investigating recently dead foraminifera (handily available in our lab!) Forams typically sink to the ocean floor soon after death, but partial or total dissolution can occur before getting there.
December 8, 2025 at 3:25 PM
One of many super cool projects started or starting in @exoceanlab.bsky.social. Keep it up Katoo!
Reposted by Tom Chalk
#exoCeanadvent Day 6: To study the deepest ocean trenches, we’re building reactors that make our lab behave like the deep ocean. Funded by @erc.europa.eu #Deep-C, they will hold cold seawater at ~1000 bar (10km water) so we* watch pressure shape chemistry and biology 🔬🌊
*mostly @sulpis.bsky.social
*mostly @sulpis.bsky.social
December 6, 2025 at 3:23 PM
#exoCeanadvent Day 6: To study the deepest ocean trenches, we’re building reactors that make our lab behave like the deep ocean. Funded by @erc.europa.eu #Deep-C, they will hold cold seawater at ~1000 bar (10km water) so we* watch pressure shape chemistry and biology 🔬🌊
*mostly @sulpis.bsky.social
*mostly @sulpis.bsky.social
Reposted by Tom Chalk
#exoCeanadvent Day 4: Why did we set up this lab? Part I. What is going to happen to climate as CO2 levels go up? @chalkyoceans.bsky.social and @erc.europa.eu project #ForCry look at CO2 in the past to better understand climate sensitivity. Part of this is making better past CO2 reconstructions.
December 5, 2025 at 6:10 PM
#exoCeanadvent Day 4: Why did we set up this lab? Part I. What is going to happen to climate as CO2 levels go up? @chalkyoceans.bsky.social and @erc.europa.eu project #ForCry look at CO2 in the past to better understand climate sensitivity. Part of this is making better past CO2 reconstructions.
Find this data, and more - in the fantastic paper by Elwyn de la Vega. Boron isotope CO2 reconstructions in the Pleistocene have come a long way... but we still have more to come. Watch this space with @mudwaterclimate.bsky.social and many others!
cp.copernicus.org/articles/19/...
cp.copernicus.org/articles/19/...
December 5, 2025 at 6:17 PM
Find this data, and more - in the fantastic paper by Elwyn de la Vega. Boron isotope CO2 reconstructions in the Pleistocene have come a long way... but we still have more to come. Watch this space with @mudwaterclimate.bsky.social and many others!
cp.copernicus.org/articles/19/...
cp.copernicus.org/articles/19/...