I have shown how cold CO2 from energy efficient thermal motors moderates airborne fertile alpha emitter transmutation and fission, reducing the Biothermic collapse from e.g. volcanic NORMs and depleted uranium. The same process works partly with SO2 from volcanic eruptions. SO2 can transmutate somehow fertile alpha emitters from volcanic NORMs in tephra, hence reducing Biothermic collapse as there are less fertile alpha emitters falling down on the flora, hence reducing the loss of endothermic photosynthesis. More photosynthesis when there is more SO2, hence observation of a “cooling” ; this “cooling” isn’t even visible with the Mt St Helens 1980 eruption which emitted very little SO2.

Here’s why this observed phenomenon, which varies hence independently of VEI, is necessarily temporary :

3 years + as maximum is quite limited and this demonstrates how volcanic “cooling” is a temporary phenomenon whereas volcanic NORMs in particular are able to stay airborne longer because of fission heat and of lift by hot CO2, as confirmed by the AI CLP-FPL (from a few months for fine tephras, it becomes 5,7 years in average in a VEI 6 eruption). Fission airborne keeps the fertile alpha emitters airborne longer and delays the warming, that happens when they downfall on the vegetation, through Biothermic collapse. This is of course particularly the case with SO2-rich eruptions… as opposed to the St Helens 1980 and the Hunga Tonga 2022 eruptions.

So the 1980 St Helens eruption is said to have “not cooled down significantly the climate”, this is related to its low SO2 emission and high NORMs emission.

Let’s generalize with recent data…

So as I said short-term cooling is powered by the SO2 fostering transmutation and fission of volcanic tephra NORMs.

What’s observed is the following : with too hot CO2, the transmutation level becomes weaker (as shown in the link at the beginning of the article) but in spite of the lower fission level (because of that), the tephras remain airborne simply because of the CO2 heat, which is why there is a kind of logarithmic link as concerns residency time of volcanic tephras and CO2 heat, as confirmed by the AI CLP-FPL. As concerns SO2, the link is the same but it is more tied to the VEI level (which fosters warmer SO2), as confirmed by the AI CLP-FPL.

This means the following : high VEI eruptions that emit lot of SO2 cool down temporarily the climate because of the reduction of NORM fallout, only. There is no such thing as “albedo variation”, it’s only related to the reduction of the Biothermic collapse, together with a fertilization effect from the volcanic ashes on the soil which fosters even more endothermic photosynthesis (hence the cooling as opposed to stall of temperatures). (There’s also a temporary reduction of solar radiation shurikenization of the flora by fertile alpha emitters because of the blurring of the sky by volcanic tephras, which is compensated by the reduction of the solar entry on vegetation (reduced photosynthesis), which is another proof that albedo doesn’t matter for climate change !)

The effect observed is always temporary because NORMs fall down later and start causing Biothermic collapse. Volcanic tephras have trapped human-emitted heat all along during the period where they were airborne, keeping them in turn aloft longer (as seen above), this is sometimes weaker than the combination of SO2-powered transmutation and soil fertilization by volcanic ashes (hence the short-term cooling), but the effect is demultiplicated when SO2 dissipates, turning the pseudo-cooling into a tangible, much bolder warm-up. And we’re not at the end of the Hunga Tonga warm-up (that conjugated with lots of emissions of warm CO2 from refinery strikes this year).

Here’s also more proof that the cooling effect is unsignificant, from a poster called Bob Weber, on Watts Up With That :

Indeed as I wrote at the beginning, SO2 is not as good for transmutation (CO2 does it 3 times better than SO2). This is why cold CO2 from energy efficient thermal motors (efficiency above 50%) is what matters really to fight climate change, not “cold SO2”.

All of the above is confirmed by the AI CLP-FPL.