Grabsteine#Felldorf (#Starzach, #Tübingen) (Friedhof) mit 164 erfassten Personen auf 125 fotografierten Grabsteinen https://grabsteine.genealogy.net/namelist.php?cem=10319
Yann Büchau 
The article about quantifying natural #CO2 emissions from mofettes at the #Starzach site in Germany with a low-cost sensor network is published now at @plosclimate:
https://doi.org/10.1371/journal.pclm.0000741
#Python #Arduino #PlatformIO #GaussianPuff #divergenceTeorem #globalWarming
Quantification of natural CO2 emissions from mofettes using a low-cost sensor network at the Starzach site in South-West Germany
We present a top-down method to derive CO2 emissions from mofettes, using only point measurement time series at irregular locations. Notably, no wind vector information is needed, as gas transport is derived from cross-correlations between sensor stations and subsequently integrated using Gauss’ divergence theorem. The method is applied to an existing low-cost sensor network at the Starzach site near the Black Forest in Germany, for which no comprehensive estimate of the total emissions exists yet. For validation, we use previous bottom-up measurements of individual mofette degassing and a Gaussian puff approach. Over a period of one and a half months around August 2022, we determine an average CO2 emission rate of 3266 kg d−1±42% over a 400 m2 area. This result is larger than expected and suggests that diffuse degassing plays a more important role at site than previously assumed. The method could also be applied for real-time monitoring of leaky CCS sites, for which the Starzach site is a natural analog.
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 with CO2 gas🎈
- or a small car (3m³) filled with liquid CO2 🚗
- or two #Minecraft blocks (2m³) of dry ice (solid CO2) 🧊🧊
😮 And this study only looks at a couple of mofettes, there are more abandoned wells in the area...
🧵
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 near #Tübingen in south-western Germany. This site is known for its natural CO2 emissions from mofettes - holes in the ground where CO2 is emitted, sometimes as little geysers when water is involved.
More on the site in my previous publications²³.
¹https://doi.org/10.31223/X51J07
²https://doi.org/10.1127/metz/2022/1125
³https://doi.org/10.1007/s10661-023-12114-8
🧵
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! 🤯)
Reading through the existing #PLOSClimate papers, mine seems a little too mathematical, but I guess it's fine? Typically one would submit this to AMT or JTECH but PLOS is a nonprofit, which I want to support.
Niels Ott Ton/Licht/BildGemeinderatssitzung in Starzach, wie üblich live auf YouTube zu verfolgen und dort auch noch für eine kleine Weile für interessierte Bürgerinnen und Bürger abrufbar.
Eine Komplettdienstleistung von Niels Ott Ton/Licht/Bild.
#livestream #hybridevent #tontechnik #veranstaltungstechnik #kamera #videoswitcher #atemminipro #blackmagic #gemeinderat #gemeinderatssitzung #teilhabe #demokratie #digitalisierung #demokratie #lokalpolitik #kommunalpolitik #dienstleister #youtube #starzach #lufs #lufsi #loudness #broadcast #broadcastaudio
Eine Komplettdienstleistung von Niels Ott Ton/Licht/Bild.
#livestream #hybridevent #tontechnik #veranstaltungstechnik #kamera #videoswitcher #atemminipro #blackmagic #gemeinderat #gemeinderatssitzung #teilhabe #demokratie #digitalisierung #demokratie #lokalpolitik #kommunalpolitik #dienstleister #youtube #starzach #lufs #lufsi #loudness #broadcast #broadcastaudio
My article @umphy Büchau et. al (2024) „A portable low-cost device to quantify advective gas fluxes from mofettes into the lower atmosphere: First application to Starzach mofettes (Germany)” is now available as #openAccess
https://doi.org/10.1007/s10661-023-12114-8
We built a partly #3dPrinted gas-channeling chimney with sensors (p, T, v̇, RH, #CO2), performed a thorough validation of all components and measured the CO2 degassing of a #mofette at the #Starzach site in southern #Germany.
A portable low-cost device to quantify advective gas fluxes from mofettes into the lower atmosphere: First application to Starzach mofettes (Germany) - Environmental Monitoring and Assessment
In this study, we introduce a portable low-cost device for in situ gas emission measurement from focused point sources of CO2, such as mofettes. We assess the individual sensors’ precision with calibration experiments and perform an independent verification of the system’s ability to measure gas flow rates in the range of liters per second. The results from one week of continuous CO2 flow observation from a wet mofette at the Starzach site is presented and correlated with the ambient meteorological dynamics. In the observed period, the gas flow rate of the examined mofette exhibits a dominant cycle of around four seconds that is linked to the gas rising upwards through a water column. We find the examined mofette to have a daily emission of 465 kg ±16 %. Furthermore, two events were observed that increased the flow rate abruptly by around 25 % within only a few minutes and a decaying period of 24 hours. These types of events were previously observed by others at the same site but dismissed as measurement errors. We discuss these events as a hydrogeological phenomenon similar to cold-water geyser eruptions. For meteorological events like the passages of high pressure fronts with steep changes in atmospheric pressure, we do not see a significant correlation between atmospheric parameters and the rate of gas exhalation in our one-week time frame, suggesting that on short timescales the atmospheric pumping effect plays a minor role for wet mofettes at the Starzach site.
🛩AG Umweltphysik Uni TübingenOur article Büchau et. al (2024) „A portable low-cost device to quantify advective gas fluxes from mofettes into the lower atmosphere: First application to Starzach mofettes (Germany)” is now available as #openAccess
https://doi.org/10.1007/s10661-023-12114-8
For this article, @nobodyinperson built a partly #3dPrinted hood with sensors (p, T, v̇, RH, #CO2), performed a thorough validation of all components and measured the degassing of a #mofette at the #Starzach site in southern #Germany.
A portable low-cost device to quantify advective gas fluxes from mofettes into the lower atmosphere: First application to Starzach mofettes (Germany) - Environmental Monitoring and Assessment
In this study, we introduce a portable low-cost device for in situ gas emission measurement from focused point sources of CO2, such as mofettes. We assess the individual sensors’ precision with calibration experiments and perform an independent verification of the system’s ability to measure gas flow rates in the range of liters per second. The results from one week of continuous CO2 flow observation from a wet mofette at the Starzach site is presented and correlated with the ambient meteorological dynamics. In the observed period, the gas flow rate of the examined mofette exhibits a dominant cycle of around four seconds that is linked to the gas rising upwards through a water column. We find the examined mofette to have a daily emission of 465 kg ±16 %. Furthermore, two events were observed that increased the flow rate abruptly by around 25 % within only a few minutes and a decaying period of 24 hours. These types of events were previously observed by others at the same site but dismissed as measurement errors. We discuss these events as a hydrogeological phenomenon similar to cold-water geyser eruptions. For meteorological events like the passages of high pressure fronts with steep changes in atmospheric pressure, we do not see a significant correlation between atmospheric parameters and the rate of gas exhalation in our one-week time frame, suggesting that on short timescales the atmospheric pumping effect plays a minor role for wet mofettes at the Starzach site.
Elias ProbstI published a preprint of our manuscript about our low-cost device to measure advective gas fluxes from mofettes to @eartharxiv:
https://doi.org/10.31223/X5ZX0D
Our design involves #3dprinting, #ESP8266 and #FOSS. 🙂
The mofette we examined emits nearly 500kg of natural (magmatic, non-volcanic) CO₂ per day!
@umphy #preprint #EarthArXiv #preprint #CO2 #co2sensors #Tübingen #Starzach #mofette
