re: Your occasional reminder that global warming is real,

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Earlier this week someone else made a similar assertion regarding a MedMal discussion. Lo and behold, when he linked the thread, it wasn't quite what he claimed.

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You're right, I checked and it's not what I claimed. I used "snarky emojis" when it should've been singular. You lasted two replies and then dropped one snarky emoji. Mea culpa! LINK

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In what sense do you think oceanic outgassing is relevant when both the atmosphere and the ocean are seeing increased levels of CO2?

In what sense are the Vostok ice cores relevant when glacial-interglacial cycles max out at ~320ppm and we're already at ~400ppm (a natural analogue for which requries you go past the glaciation cycle entirely to the pre-Ice Age Pliocene)

Put another way, if temperature and not CO2 is the driver in the current climate change, and the ice cores show a temperature change of ~10° leading a feedback of ~100ppm CO2 by several centuries, why now, after barely 1° of temperature change in little more than one century, has the CO2 level already risen ~120ppm?

EDIT: I forgot to add a spiel about the isotopic ratio of C-13 but that can wait until later.

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As temperature increases, and if CO2 is the sole responsible culprit for that increase, oceanic outgassing should not only be relevant, it should be potentially catastrophic.

The relevance is in both the sense of a cycle itself, and in its cause.

Are you trying to ask if man is contributing to increased CO2? If so, the answer is definitively 'yes'.

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Why? This exercise shows that even under very friendly assumptions (e.g., exchange down to 3800m) a 1° rise in temperature results in a 10ppm increase due to outgassing. Which is dwarfed by the direct increase required to drive 1° in the first place (~100ppm).

This is to be expected because while the temp->CO2 feedbacks (and other feedbacks such as water vapor and ice-albedo) are positive (>0), they are not runaway (>1) since we don't live on Venus.

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That exercise seems designed to demonstrate error in the premise that 400ppm CO2 is largely d/t increased temperature, rather than anthropogenic output.

Unless I'm missing something, the exercise does not seem to address hazard of outgassing with a coincident assumption of CO2 as sole cause of the presumed 1°C temperature rise.

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That's what it was designed to do, but it also works to prove my point here. Since if anything a coincident increase in atmospheric CO2 would reduce, not increase, the outgassing feedback of a 1° temp increase.

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Wut?

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I will assume your confusion was genuine and elaborate on the last point: Henry's law assumes that a system is at equilibrium. If the temperature is raised and all else stays equal, then we would see considerable outgassing. But currently, the system is not at equilibrium, because the temperature is rising AND we're continuing to add more CO2 to the atmosphere. (It's actually NEVER strictly at equilibrium because of biological cycles and ocean stratification which drastically limit the application of basic high school chemistry like Henry's Law, but nobody reads multi-paragraph posts.)