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nobodyinperson.fosstodon.org.ap.brid.gy
Yann Büchau :nixos:
@nobodyinperson.fosstodon.org.ap.brid.gy
25 followers 1 following 460 posts
(he/him) Environmental Scientist/Meteorologist @umphy. Built a low-cost CO₂ sensor network to monitor natural CO₂ emissions […]

[bridged from https://fosstodon.org/@nobodyinperson on the fediverse by https://fed.brid.gy/ ]
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nobodyinperson.fosstodon.org.ap.brid.gy
Kann es sein, dass die #ausweisapp bzw. irgendein notwendiger Server nicht tut? Irgendwie gibts immer nen Fehler https://www.autentapp.de kann nicht kontaktiert werden 🤷

Nachwirkungen der #cloudflare Outages? 🤔
Ausweisen Authentisierung fehlgeschlagen https://www.autentapp.de Es konnte keine sichere Verbindung zum Anbieter aufgebaut werden. Uberpriifen Sie die Netzwerkverbindung und probieren Sie es spater erneut. Wenn dies nicht hilft, kontaktieren Sie unseren Support.
November 21, 2025 at 3:00 PM
nobodyinperson.fosstodon.org.ap.brid.gy
My very first programming projects when I started self-teaching around 15 years ago were about accounting. I was unhappy with keeping track of expenses in a physical notebook, and the spreadsheet I made was also very limited. And existing #foss solutions like […]

[Original post on fosstodon.org]
simbuto example screenshot. some CSV on the left specifying recurring monetary transactions with time and amount uncertsinties, and a plot with a monte-carlo simulation of those on the right.
November 21, 2025 at 12:28 PM
nobodyinperson.fosstodon.org.ap.brid.gy
Hey @plosclimate, I receive mails from a weird domain newgen.co, which looks super fishy to me. Is that really you?
Mail from pclm@newgen.co saying to please click link, saying something about LaTeX macros.
November 7, 2025 at 6:27 AM
nobodyinperson.fosstodon.org.ap.brid.gy
Holy shit, it (finally) happened: Someone (I have nothing to do with) cited a paper of mine. 😱

Okay, it's an #mdpi paper¹, but I'll take that.

For nearly 8 years of #phdlife now (look like I'll be done in spring 💪), this feels a bit... underwhelming, I guess […]

[Original post on fosstodon.org]
Thunderbird email screenshot. Email from ResearchGate to Yann Büchau, subject: Yann, a recent article cited your research Yann, we found a recent citation of your research
September 28, 2025 at 12:39 PM
nobodyinperson.fosstodon.org.ap.brid.gy
Once you are done fighting it, documents typeset with LaTeX are pretty damn rad! 🚀

The automations you can put into place to help you focus on the actual writing are really something else:

- different modes for notes, submission, and publishing
- acronym […]

[Original post on fosstodon.org]
September 17, 2025 at 4:41 PM
nobodyinperson.fosstodon.org.ap.brid.gy
Found even more 🚒 fire hydrants in #unterkirnach, ~45 now, these suckers keep popping up everwhere 😅

#mapping #openstreetmap #firefighter
CoMaps screenshot of Unterkirnach as above posts, now ~45 hydrants are marked
September 13, 2025 at 8:25 AM
nobodyinperson.fosstodon.org.ap.brid.gy
The results are that the investigated mofette field in #starzach emits roughly three metric tonnes of CO2 per day (3000kg/d).

To put this into perspective: This 20x20m mofette field fills daily:

- a smaller hot air balloon (CO2 gas)🎈
- or a small car (3m³) […]

[Original post on fosstodon.org]
Fig 9. Average daily CO, emission rates at the Starzach site over 47 days. The blue and orange lines consist of the respective average CO2 emission rates ṁ derived with Eq (5) in the night between 18:00 and 06:00 UTC as motivated by Fig 7. One line shows an average of 517kg/g near a mofette, which matches previous measurments, another line shows the total emissions for the whole investigated region with an average of 3266kg/d, which is similar to the extraction rate of an industrial well used the 1980 in 1km distance.
September 5, 2025 at 10:39 AM
nobodyinperson.fosstodon.org.ap.brid.gy
With Gauss' divergence theorem, we can then use this CO2 transport vector to derive the total CO2 emissions per time [kg/s].

🧵
Gauss' divergence theorem: the total CO2 emission mass rate [kg/s] ṁ equals the integral of the CO2 transport vector over a chosen boundary and also equals the volume-integral of its divergence
September 5, 2025 at 10:17 AM
nobodyinperson.fosstodon.org.ap.brid.gy
These high CO2 concentrations then cause strong signals in CO2 sensors placed near the surface. Often, a distinct time shift between time series of two stations can be made out. We quantify this by finding the best cross-correlation between them.

🧵
Fig 4. Zoomed view of A positive shift in the lowest panel means that the time series of of station s6 needs to be moved forward in time (into the future) to match the time series of station s26. The top panel shows that the two CO2 stations 6 and 26 have quite similar CO2 timeseries, but one can see they are time-shifted against each other. This estimated time shift is shown in the lowest panel and is around 10 seconds. How good this time shift can be estimated is shown in the middle plot, which is the highest cross-correlation that was found between the stations in a 10 minute window.
September 5, 2025 at 9:36 AM
nobodyinperson.fosstodon.org.ap.brid.gy
With these CO2 emissions, near-surface CO2 concentrations at the Starzach site are untypically high, here it goes up to 40000ppm (4%vol), which is roughly the concentration of CO2 a human exhales.

🧵
Fig 2. Typical 24 hour time series of a near-surface CO2 station 6 at the Starzach site’s main mofette area with global average CO2 concentration reference of 415 ppm (top), and peak duration and time between peaks (bottom). The top graph shows that at night, CO2 concentrations are in the five digits up to 40000ppm (4%vol) and during the day it's lower but still a lot (10x) larger than the typical ~415ppm.
September 5, 2025 at 9:30 AM
nobodyinperson.fosstodon.org.ap.brid.gy
In this¹ paper, I present a method to derive #co2 movements and total emissions from cross-correlations between a bunch of CO2 stations (black arrows) at the Starzach site in south-western Germany. This site is known for its natural CO2 emissions from […]

[Original post on fosstodon.org]
map of the 20x20m main mofette area at the Starzach site in south-western Germany, where natural CO2 is emitted. Elevent points labeled S<number> are scattered across the site, these are CO2 measurement stations, and three purple stars, indicating visibly active mofettes. Black arrows show the CO2 movement derived from cross-correlations between CO2 timeseries. The wind speed is very low (<0.2m/s) and in a white rectangle near a big mofette the average is 2g/m²/s for the CO2 transport and 22.5cm/s for the movement speed. A shade of red shows CO2 concentrations between 100 and 10000 ppm.
September 5, 2025 at 9:27 AM
nobodyinperson.fosstodon.org.ap.brid.gy
Has anyone here published with @plosclimate?

My manuscript is slowly approaching submission state. It is a very technical paper about the essence of my #phd: quantifying natural #co2 emissions at the #starzach site (Turns out, it's a few tonnes per day! 🤯) […]

[Original post on fosstodon.org]
A map of a 20 by 20 meter meadow, several white scattered dots labeled s and a number. Arrows depicting co2 movement speed are pointing smoothly to the upper left-hand corner across the map. A red transparent blob in the center indicates a high co2 concentration, maybe 10000ppm. It's the 20.07.2025, 21:35.
August 16, 2025 at 7:47 AM
nobodyinperson.fosstodon.org.ap.brid.gy
K1 ist jetzt so weit, dass man mit Schablonen Spaß haben kann 😀

#parentingbingo #3dprinting #3ddruck #papasein #Fedieltern
Drei weiße rechteckige 3D-gedruckte Schablonen: Katzen, ein Kalb, Hundekopfsilouhette
August 6, 2025 at 6:38 AM
nobodyinperson.fosstodon.org.ap.brid.gy
Man kennt sie, die 3-Paus-Gase...

#haraldlesch #treibhausgas #co2
Harald Lesch Video, Untertitel: „Denn wir schießen nach wie vor 3-Paus-Gas”
July 31, 2025 at 3:11 PM
nobodyinperson.fosstodon.org.ap.brid.gy
Wife and I improvised a wardrobe from scrap stuff we had laying around. 0€ spent, #3dprinting holds everything together.
A "wardrobe" with a white plate below which there is a wooden bar to hang jackets etc. 3D printed brackets hole everything together. A "wardrobe" in the space between an IKEA PAX and a wall, built from two of these compressed wood planks and a wooden bar to hang jackets from. On top there are two boxes with shoes and stuff and a curtain can be used to hide everything.
July 29, 2025 at 8:51 AM
nobodyinperson.fosstodon.org.ap.brid.gy
Mein Fahrradhändler (sehr kulant und hilfreich!) hat mir jetzt Kootu Metall-Klapppedalen geschenkt. Die machen einen wesentlich besseren Eindruck. Pedalen hinten mit Inbus, An der Achse keine Mini-Mutter, sondern genietet oder so, mal sehen. 👍
Jetzt miz Kootu Metall-Klapppedalen
July 26, 2025 at 8:40 AM
nobodyinperson.fosstodon.org.ap.brid.gy
Ha, now they have landed in @CoMaps as well! 🤗
Same screenshot, but in a fresh CoMaps install, all hydrants visible
July 25, 2025 at 2:49 PM
nobodyinperson.fosstodon.org.ap.brid.gy
Sneak peak für meinen talk „Das Leben in Git” beim #tdf in #Tübingen am 26.07.2025, 19:00 in der Westspitze.

https://cfp.cttue.de/tdf4/talk/EECDBS/

#git #gitannex #forgejo #forgejoaneksajo
Vince McMahon getting increasingly more excited meme. panels: 1 (mildly excited): files (we all got 'em) 2 (more excited): git (tracking files) 3 (bigger eyes): git-annex (BIG files) 4 (lean back, o mouth): forgejo (git server) 5 (laser eyes): forgejo-aneksajo (+annex support)
July 23, 2025 at 1:26 PM
nobodyinperson.fosstodon.org.ap.brid.gy
@dcz You're right, why didn't I do this before! 🤯
xfce4-terminal with vim open (some Python code) and Noto Sans Regular (not monospace!) as font. It looks terrible, the characters don't really follow a grid, inter-character spacing is all over the place
July 23, 2025 at 11:29 AM
nobodyinperson.fosstodon.org.ap.brid.gy
Can you guess what this is? 😉
A blue/white plastic thing with a curved form bulging upwards, maybe 7cm diameter back side, reveals a hole into a cavity at the top and another throughhole at the bottom
July 18, 2025 at 6:28 AM
nobodyinperson.fosstodon.org.ap.brid.gy
Holy cow 😅 Iterating on :nixos: #nixos SD card images surely adds up...
nix store gc output showing ~237GB being freed by deleting unused stuff
July 16, 2025 at 7:15 PM
nobodyinperson.fosstodon.org.ap.brid.gy
Da haben wir den #Designfehler: eine *winzige* Mutter, die die ganze Pedale fixiert. Klar, das hält bestimmt! 🤦

#designfail #fahrrad
KlappPedale, Kappe an der Achse fehlt, drunter sieht man eine Mini-Mutter, die ein Kugellager fixiert
July 14, 2025 at 7:47 AM
nobodyinperson.fosstodon.org.ap.brid.gy
Nice, #python 3.9 is very soon EOL [1], so it is finally fine to use Structural Pattern Matching [2] (i.e. the `match` statement, a `switch` on steroids) everywhere! 🥳

1] [https://devguide.python.org/versions/
2] [https://peps.python.org/pep-0636/
Screenshot of linked website, gantt chart of Python version lifetimes, cascading. Python 3.9 obly has a little bit of bar left.
July 13, 2025 at 5:27 PM
nobodyinperson.fosstodon.org.ap.brid.gy
Es ist so krass, wie unterdimensioniert #ebike's sind. Bezahlst Dich dumm und dämlich, denkst, Du kriegst was Dauerhaftes mal, ohne Platten und Reparaturen ständig, Pustekuchen: fliegt die Pedale ab. 🙄 Nachdem es einen "unplattbaren" Mantel zerstochen hat […]

[Original post on fosstodon.org]
Klappbare Fahrradpedale ist vom Schaft ab, Kugellager ist hin
July 12, 2025 at 6:20 PM
nobodyinperson.fosstodon.org.ap.brid.gy
I am sitting here in #Tübingen while my colleagues @umphy are in the mountains in #austria (#Inntal) and fly our #multicopter​s with PARASITE payload (running :nixos: #nixos) to do wind and other meteorological measurements. I can fix issues in the software […]

[Original post on fosstodon.org]
A dji Matrice M300 multicopter on asphalt with 3d printed parts attached all over, two "chimineys" at either side for particle measurements and a black "belly" underneath, with temperature, humidity and gas sensors.
July 11, 2025 at 9:32 AM