So sure in the short term (years) no eruption is good. But in the long term there will be poorer soil, or a huge amount of energy/chemicals consumed to keep the soil usable.
It's far from clear that it's better for the ecosystem to stop a volcano (or supervolcano). What's next stopping earthquakes? Keep plates from moving? Stopping erosion? Preventing rivers from migrating?
Mucking with nature to prevent the natural cycle of life has gone pretty poorly so far. Floods are getting worse, rivers are moving faster, coastal cities are losing their marshes, cities on rivers are at a higher risk than ever of flooding.
Check out the updates on Mt Saint Helens area in the post eruption documentary. It's quite vibrant and recovered much faster than scientist expected.
1) Tell humans their suffering doesn't matter.
2) A super-volcano eruption is several orders of magnitude worse than St. Helens, a scale that human history has not seen yet. It would affect the whole planet and wreck ecosystems in the whole planet, far beyond North America. We're talking about likely end of civilization. You don't have logic against that.
As for the comparison to climate change, it's flawed on its face. Climate change wasn't exactly planned. There's a difference between that sort of change and a focused, targeted effort to change a particular element of nature (in this case, cooling a supervolcano) and an unintentional consequence of industrialization.
In any case, any effort to roll back the effects of climate change is going to involve some form of climate engineering. That could include anything from artificial carbon sequestration to a massive solar dust shade at L1 blocking a small fraction of solar radiation to give us the time needed to implement those sequestration systems. Or any number of other proposals. Should we just accept higher temperatures instead, even if we manage to slow or even halt the progression? We muck with nature all the time, and we're going to have to continue to do so in order to protect it.
After all there are many potential causes of food shortages and the risks are getting worse with each year because of additional pollution, global warming, and increased population.
I don't want anyone to die, but does seem short sighted to depend on soil enriched by previous eruptions, then to prevent future ones.
Or, maybe, we could prevent it all from happening in the first place.
I don't understand why you're so stuck on not preventing mass death. Did you not think this through before commenting and now your ego won't let you back down? Or are you just trolling?
It would make for a good story premise for a movie/TV show/video game, but not so much fun to actually live through.
Seems far from sure that a world wide cloud of ash might well do more benefit (better soil, cooler temperatures, helping dead zones in the ocean) than harm.... assuming we plan for it.
First, you need to consider that, in the long run, that thing is going to explode and will certainly destroy a lot of ecosystems around the world.
Second, the only ecosystem that depends on the heat are the archea on the geysers and hot vents. But the heat loss along years would be so small that their ecosystem can endure for a lot more centuries.
Third, it is very hard to find a way to generate so much energy without increasing carbon footprint and generating even more ecosystems destruction.