Samuel Brenner
@sdbrenner.bsky.social
4.8K followers 1.3K following 20 posts
Postdoc at @caltech.edu studying sea ice-ocean interactions. PhD in physical oceanography from the University of Washington. 🇨🇦(he/him) https://sdbrenner.github.io/
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sdbrenner.bsky.social
Caltech has recommended that international scholars on H-1B visas (like myself) not leave the US.
Screenshot of an email from Caltech's international student services reading:

"On September 19, 2025, the Presidential Proclamation Restriction on Entry of Certain Nonimmigrant Workers was issued.  The proclamation requires H-1B employees who are seeking to enter the United States on or after September 21, 2025 to either have their employer pay a $100,000 supplemental fee or to receive a determination from the Department of Homeland Security that their entry is in the national interest and does not pose a threat to the security or welfare of the United States.  Until further details are published about the national interest determination, we urge H-1B employees not to leave the United States.  Similarly, any H-1B employees who are abroad, should attempt to return to the United States before midnight on September 20, 2025."
sdbrenner.bsky.social
I'm very grateful to @earthsciencewomen.bsky.social and the volunteers that moderate the list, and the community members that contribute. Thanks to all of you!
sdbrenner.bsky.social
I haven't looked into whether there are differences based on location, subject area, etc. (and I'm not currently planning to)
sdbrenner.bsky.social
That said, I think this figure is instructive. It might be too early to say whether the 2025-2026 job cycle is going to be "normal" or not, but so far it seems to be within the general range of other cycles. But, to me, it is clear that the 2024-2025 job cycle was not normal.
sdbrenner.bsky.social
Since everything is crowd-sourced, year-to-year variability reflects not just the job market, but also people's interaction with the list, visibility of postings, moderation choices (e.g., when to rollover to a new year-cycle, etc.), and other factors—so I wouldn't read much into direct comparisons.
sdbrenner.bsky.social
Here, I'm just plotting the dates jobs were added to the "Tenure Track/Permanent jobs" for each of the job-search cycles going back to 2019-2020.
sdbrenner.bsky.social
The list is a really excellent community resource of crowd-sourced Tenure Track/Permanent jobs, Non-Tenure Track Faculty, and Postdoc positions hosted by @earthsciencewomen.bsky.social. It contains postings worldwide, but is mostly US-centric.
sdbrenner.bsky.social
As a postdoc on the job market, I've been worried about the impact of ongoing funding/policy uncertainties on faculty positions. So I decided to compare the progression of faculty jobs this cycle to previous years based on positions posted to eswnonline.org/online/earth...
Line chart showing the cumulative number of Earth and Environmental Science faculty job postings by date added to the ESWN Jobs List for each hiring cycle from 2019–2020 through 2025–2026. The x-axis shows dates from April to August of the following year, and the y-axis shows the number of jobs (0–450). Each hiring cycle is represented by a line: earlier years (2019–2020 through 2024–2025) appear in progressively darker shades of blue, and 2025–2026 in red. Most years show rapid growth in postings from September to December, with totals levelling off by spring. The line for 2024–2025 shows a decreased growth after mid-November
sdbrenner.bsky.social
Does anyone have good suggestions for where to find these foreign research jobs? The job search email listservs I am already on tend to be somewhat (though not entirely) US-centric, so I wonder if there are others I should subscribe to to cast a wider net?
sdbrenner.bsky.social
Saw this article on my feed today, and had to come back and find your post so I could share:
www.scientificamerican.com/article/the-...

The article claims that it's not about harder hits (fitting with your point re moment of inertia), it's about better aim.
Reposted by Samuel Brenner
salganik.bsky.social
If you are into Arctic sea ice thermodynamics, here is our new dataset of 82 CRREL ice mass balance buoys deployed in 1997–2024 with estimates of snow and ice thickness and their interface evolution: doi.org/10.5281/zenodo.15096485
Two panels show the temporal evolution of snow (top) and sea ice (bottom) thickness from various ice mass balance buoys listed in the legend (right).
Reposted by Samuel Brenner
katharinehayhoe.com
Casual final sentence here, way to bury the lede CBC!

"Carney is expected to call an election by the end of the week, to take place in late Apr or early May."

If you're out of the country and you want to vote, here's what you need to do as soon as the election is announced ⬇️
Reposted by Samuel Brenner
saragoeking.bsky.social
Sharing as a member of AGU's pubs committee:
AGU is joining a lawsuit in support of federal workers. They need stories/examples of how loss of federal jobs is affecting society. Please share this request with your colleagues & communities. Deadline is this week.💧🧪🌲
forms.monday.com/forms/f553b2...
AGU joins suit supporting fired federal employees
The case brought by federal employee unions and nonprofit organizations asserts that OPM’s directive to fire probationary employees at the National Science Foundation and other agencies was illegal.
news.agu.org
sdbrenner.bsky.social
If you haven't already done so, sign the House of Commons petition urging the Government of Canada to move off of Twitter/X:
www.ourcommons.ca/petitions/en...
(Canadian citizens or residents only)
Petition e-5359 - Petitions
www.ourcommons.ca
Reposted by Samuel Brenner
seaice.de
Sea ice paper alert, congratulations to my colleagues!

Krumpen, T., von Albedyll, L., Bünger, H.J. et al. Smoother sea ice with fewer pressure ridges in a more dynamic Arctic. Nat. Clim. Chang. (2025). doi.org/10.1038/s415...

#Arctic #climate 🌊 🥼❄️
rdcu.be/d5rtv
Smoother sea ice with fewer pressure ridges in a more dynamic Arctic
Nature Climate Change - Pressure ridges, a characteristic feature of Arctic sea ice, play an important role in the ecosystem but pose challenges to shipping. Here the authors use aircraft...
rdcu.be
Reposted by Samuel Brenner
jgroceans.bsky.social
Hello from the JGR:Oceans team 🌊🌊🌊

We're very happy to be the first AGU journal on Bluesky!
I guess that also makes us the best AGU journal on Bluesky 😆

Our Editors will be posting here about our latest news & views, message/tag us if you'd like us to highlight your science 👍
Reposted by Samuel Brenner
andrewdessler.com
Welcome @agu.org! It’s great to have the American Geophysical Union here!
Reposted by Samuel Brenner
biolumijeffence.bsky.social
Hi all! I've seen an uptick in follows from fellow Federal #Canadian #scientists over the last while, so I figured I'd create a starter pack!

Check here to follow federal Canadian science & scientists!🧪

Reply here if you want to be added; DM me if you want to be removed.

go.bsky.app/Cjr4wAD
Reposted by Samuel Brenner
katharinehayhoe.com
Please welcome the @ametsoc.bsky.social to Bluesky!

AMS advances the atmospheric & related sciences (including of course climate), applications, and services for the benefit of society.

I've added them to this starter pack of scientific organizations that do climate-related work ⬇️
sdbrenner.bsky.social
That somewhat recalls the one-sentence introduction section from a Walter Munk paper
The image shows the title and introduction of a lecture paper, reading:

Once Again—Tidal Friction
Walter Munk
(Harold Jeffreys Lecture delivered at Burlington House, 29 March 1968)

1. Introduction
In 1920 it appeared that Jeffreys had solved the problem of tidal dissipation. We have gone backwards ever since.
Reposted by Samuel Brenner
georgeimatsumoto.bsky.social
🧪📍 🌊 🦑 Applications are now being accepted from undergraduate students, graduate students, post-docs, and early-career scientists to participate in an NSF-funded research cruise aboard the R/V Marcus G. Langseth mailchi.mp/ldeo/langset...
Call for Participation: R/V Langseth Research Cruise
mailchi.mp
sdbrenner.bsky.social
I finally got around to adding a Bluesky profile link to my personal research website.
The image is a screenshot of a website featuring a navigation menu on the left side with sections: "home," "about me," "research," "publications," "curriculum vitae," and "'ocean robots' posters." Below these, icons link to email, GitHub, Bluesky, Instagram, and LinkedIn.

On the right, there's a profile photo of me wearing a bright orange Mustang survival suit during Arctic research. Below my name, "samuel d. brenner," I'm identified as a "post-doctoral research associate at Caltech." A section titled "research" follows, describing my work on studying processes in the Arctic.