Daan Reijnders

According to this plot and associated thread, satellites already in orbit, providing invaluable views of our ocean and earth will be turned off. Future missions almost uniformly cancelled. It’s almost too destructively insane to believe true. 🌊

Alright, seems like that NOAA thing was very very poor timing, so taking down my worried post - BUT still worried about NOAA’s fate with the doge hounds around.

Important statement by the American Association of University Professors warning against "anticipatory obedience".
www.aaup.org/report/again...

Doge staffers enter Noaa headquarters and incite reports of cuts and threats Members reportedly sought access to IT systems at agency that Project 2025 has called ‘harmful to US prosperity’

Self-proclaimed defenders of free speech are busy suppressing information that they consider to be at odds with their ideology of concentrating power and wealth among the few. Censorship, propaganda and disinformation are the tools to keep the public docile.
www.theguardian.com/us-news/2025...

We can also look at global daily absolute temperatures (rather than anomalies), which show just how much global temperatures have shifted over time:

Symposium on the science-industry interface of marine Carbon Dioxide Removal On January 21st, a second symposium will be held on marine Carbon Dioxide Removal. This time, the focus will be on the science-industry interface.

The Sustainable Ocean Community (@utrechtuniversity.bsky.social & @niozsearesearch.bsky.social) is organizing the second installment of their #mCDR symposium series, this time on the science-industry interface. 21 jan in Utrecht. Full program TBA.
www.uu.nl/en/events/sy...

Progression of ocean interior acidification over the industrial era The rapid downward progression of anthropogenic carbon accelerates ocean interior acidification and threatens marine biota.

Ocean Acidification is reshaping life and biogeochemical cycles.
In our latest study, Niki Gruber and I reconstructed its progression in the global ocean interior over the industrial era, based on our previous estimates of anthropogenic carbon accumulation.
doi.org/10.1126/scia...

A 🧵about the 🌊...

The Earth's Carbon Cycle YouTube video by Robert Rohde

I really love this animation of the C cycle, and how we’re affecting it through burning fossil fuels, by @rarohde.bsky.social

I use it in my teaching every year!
youtu.be/dwVsD9CiokY

Wave of new Wikipedia articles by oceanography students The English Wikipedia now has a large number of articles on oceanography after 40 students of Dynamic Oceanography each wrote an article for the platform.

Reminds me of the wiki articles that students at Utrecht University wrote for an oceanography course, instead of a typical paper assignment: www.uu.nl/en/news/wave...
So much nicer than laboring for hours for something never to be revisited (except, hopefully, by your own memory)

Thanks a lot to my co-authors: Michael Denes, Siren Rühs, Øyvind Breivik, Tor Nordam and Erik Van Sebille!

We explore all of this in the manuscript. We provide technical explanations for the cause of this bias but also do some more practical experiments in the Atlantic using typical mesoscale set-ups, and find the bias is significant at timescales of less than 180d 😬 Previous research could be affected!

We find that this is due to a reversal of stability to numerical errors in divergent and convergent regions as time is reversed. But not just RK4 (used in software like Parcels) is affected; also the analytical scheme (TRACMASS and ARIANE) can suffer from biases near the surface due to the B.C.s!

This fig shows which bins in the ACC channel are over- (red) and underrepresented (blue) in particle counts after forward and backward integration. Esp Runge-Kutta 4 (with dt = 10 mins, which is on the shorter end of typical sims) shows significant biases with stationary and time-evolving flows.

In one experiment, we initialized particles uniformly in an ACC channel model (mesoscale) and tracked particles forward and then backward for 180 days. With perfect numerics, particles should then just end up at their original locations, but numerical errors shake things up a lot! (2/n)

Do you use Lagrangian (back)tracking? 🕙🔄 My last thesis chapter identifies how divergence can amplify numerical errors in Lagrangian tracking, and how especially for backtracking this can lead to substantial biases in source inference.

Find the pre-print here: essopenarchive.org/users/560859...

(2/2) We track DIC changes over a year and split these into biogeochemical and mixing contributions. For 4 pathways, we compute magnitudes and timescales at which BGC and mixing alter DIC. Mixing during subduction changes DIC in a parcels the most, but most parcels persist in NASTMW over the year.

Disentangling Carbon Concentration Changes Along Pathways of North Atlantic Subtropical Mode Water Carbon transformations along pathways of North Atlantic Subtropical Mode Water are split into mixing and biogeochemical contributions Along paths into, within, and out of this mode water, mixing ...

Have to start using bsky and a paper alert is a classic 📝
Our paper (w/ Dorothee Bakker and Erik van Sebille) on carbon transformations in North Atlantic Subtropical Mode Water is out in JGRO. We disentangle DIC changes in Lagrangian parcels (1/2)
agupubs.onlinelibrary.wiley.com/doi/10.1029/...

I made it over!!! 😮‍💨 Time to rebuild my bubble