PQ> This is what I almost half-remembered...

   Not exactly a Siberian volcano? 8-)

   Meteorites/asteroids and volcanoes sure have a severe impact on our climate,
but that never lasts more than a human lifetime.

   What we have now is a continuous abuse of our atmosphere that so far has
been going on for more than a century -- and there seems to be no end to it,
it's even escalating exponentially. :(

   Such a catastrophic, long lasting destruction is absolutely unprecedented in
Earth's history of life.



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