No Vesuvius? If we are talking about historic records or getting into culture that should be one of the top ones. And if we are talking about climate effects on mankind, even if no written records, Toba could had unmade history 70k years ago.
> In the months and years after the eruption, average summer temperatures fell 0.6 degrees Celsius (1.1 degrees Fahrenheit) in the non-tropical regions of the Northern Hemisphere.
We could surely use that now... We could skip the tsunami though
I am guessing the ash cloud is blocking the heat from the sun to reduce the temperatures. But if the heat is generated from underneath the cloud, an ash cloud will not help.
Global climate change is from trapping more sunlight energy (greenhouse effect), not industrial heating.
But more importantly: between tsunamis and deaths due to lung duress, counterproductive.
Well it would also hurt crop yields which still isn't great.