It's also interesting that Mount Krakatoa caused a case of global cooling! Which is it? Do carbon emissions cause warming by trapping warmth on the surface or do they cause cooling by blocking sunlight from reaching the ground? I've never heard a reasonable explanation from anyone about how the same gases can be the cause of global warming and global cooling. I think the answer to that depends on your political leanings.
I think you got something confused. It's both carbon causing 'global warming' (if you believe in it) and the cooling after the eruption of great volcanoes.
But the first is carbon dioxide, and the second is made up of larger particles you'd refer to as ashes. These ashes build huge clouds, preventing sunlight from reaching the ground. And without sunlight, it gets darn cold down here.
Since we already mentioned volcanoes, we should talk about the so-called super volcanoes as well.
There are several known super volcanoes around the world. One of them,
Lake Toba in Indonesia, erupted about 75,000 years ago, spewing forth about 2,800 cubic kilometers of ashes (Compare: Krakatoa: 25 km³; Mount St. Helens (last eruption): ~1.2 km³) and causing the so-called Millenial Ice Age.
Here is a list of other supervolcanoes and information on their eruptions:
Lake Taupo, New Zealand, erupted 26,500 years ago; ejecta volume: 1,170 km³
Yellowstone Caldera, Wyoming, erupted
- 2.2 million years ago; ejecta volume: ~2,500 km³
- 1.3 million years ago; ejecta volume: ???
- 640,000 years ago; ejecta volume: 1,000 km³
Valles Caldera, New Mexico, erupted
- 1.6 million years ago
- 1.2 million years ago; ejecta volume: >2400 km³ (each? together? Couldn't make sense of my source)
Long Valley, California, erupted 760,000 years ago; ejecca volume: 2,400 - 3,600 km³
La Garita Caldera, Colorado, erupted 27.8 million years ago; ejecta volume: ~5,000 km³
Oh, and some of them, namely the Yellowstone Caldera, Lake Taupo and Long Valley are still *very* active. Plus
Aira, Japan which doesn't have a claim to such a 'mega-colossal' eruption - yet.
Apart from that, I have to agree with Paul: We can do nothing to preserve our environment and find out it would have been necessary, or we can do something and find out it wouldn't have been necessary. Personally, I prefer the latter.
Another thought: People interested in this topic should read Michael Crichton's
'State of Fear'. Really interesting, if a bit one-sided.
