We’re filling the atmosphere with CO2 like a bathtub with water. Most of it stays for millennia. That is why the cumulative emissions (the total amount, as pictured here) and not yearly emissions determine the amount of #globalwarming.
@oliverknabe Does the bathtub metaphor extend to the bathtub •overflowing•, i.e. crossing some threshold where the water can’t absorb more CO2, the atmospheric CO2 suddenly starts increasing at a much faster pace?
@inthehands I am not the scientist here and cannot answer the question, but the overflowing bathtub as a new metaphor reminds me of the tipping points like the possible collapse of the Atlantic current AMOC: fediscience.org/@rahmstorf/115…
@inthehands @oliverknabe we just don’t get it, I remember volcano lake in Azores, no water flowing out, all stays in the lake, efforts to keep it clean, no boats, jet skis, but pesticides from nearby agricultures running off into the lake causing trouble, we seem just too blind to ever see the whole picture 🤷🏽♀️its like we are horses with blinkers
@inthehands @oliverknabe Also not a climate scientist, but Paul your metaphor might be more appropriate for the ocean’s ability to absorb CO2. There’s presumably only so much carbonate that the ocean can hold before it becomes less efficient at converting dissolved atmospheric CO2 to more carbonate. This paper argues that this is already happening:
A new factor, γCO2, can effectively measure ocean absorption capacity for carbon dioxide and acidification as ocean acidification intensifies, according to calculations using global temperature and salinity data.
If you mean the #oceans with "water", then: not really. As there are multiple processes responsible for #CO2 uptake there is not a single #TippingPoint but a degradation: "Warmer sea-surface temperatures reduce CO2 solubility, and increased thermal stratification attenuates ocean carbon uptake through suppression of nutrient upwelling and export of anthropogenic carbon to deep water." (4.2) From long read: annualreviews.org/content/jour… (via x.com/jikorsbakken/status/1857…)
Paul Cantrell
in reply to Prof. Stefan Rahmstorf • • •Does the bathtub metaphor extend to the bathtub •overflowing•, i.e. crossing some threshold where the water can’t absorb more CO2, the atmospheric CO2 suddenly starts increasing at a much faster pace?
Oliver Knabe
in reply to Paul Cantrell • • •@inthehands I am not the scientist here and cannot answer the question, but the overflowing bathtub as a new metaphor reminds me of the tipping points like the possible collapse of the Atlantic current AMOC: fediscience.org/@rahmstorf/115…
Prof. Stefan Rahmstorf
2025-08-28 19:07:53
Katja
in reply to Paul Cantrell • • •Curtis Nordgaard
in reply to Paul Cantrell • • •@inthehands @oliverknabe Also not a climate scientist, but Paul your metaphor might be more appropriate for the ocean’s ability to absorb CO2. There’s presumably only so much carbonate that the ocean can hold before it becomes less efficient at converting dissolved atmospheric CO2 to more carbonate. This paper argues that this is already happening:
nature.com/articles/s43247-025…
A new indicator can assess absorption capacity for carbon dioxide and ocean acidification - Communications Earth & Environment
NaturePaul Cantrell
in reply to Curtis Nordgaard • • •Yes, sorry: my post was incoherently written, and what you said is what I was attempting (and failing) to talk about!
Curtis Nordgaard
in reply to Paul Cantrell • • •Sepia Fan
in reply to Paul Cantrell • • •"Warmer sea-surface temperatures reduce CO2 solubility, and increased thermal stratification attenuates ocean carbon uptake through suppression of nutrient upwelling and export of anthropogenic carbon to deep water." (4.2)
From long read:
annualreviews.org/content/jour…
(via x.com/jikorsbakken/status/1857…)