How to reduce environmental destruction?

How does the threat of anthropogenic global warming compare with natural threats, such as supervolcanoes and asteroids?

• As background for this question, I had an argument with a friend which we cannot resolve without reference to science. My point was that (a) anthropogenic global warming is caused by our process of technological development, and while the two might become independent in the near future, there is some extent to which we have to compromise technological development if we want to radically minimize global warming, (b) when the sun dies, biodiversity will drop to zero (at least in this region of the universe), and the only way life can persist is with a species that has the technology to live without the sun, (c) therefore some short-term environmental destruction can be justified to help us cope with long-term environmental destruction. My friend's point was that if we go slower, we can be more efficient in terms of the technological deveopment to environmental destruction ratio, and since the sun's death is far off, we have no incentive to compromise efficiency for speed (we both agree that a diverse environment can help us in the long-run, e,g. through biomimetic engineering). My response was that the sun's death is a deadline, and that other large-scale catastrophes can hit us before the deadline comes; the slower we progress, the greater the risk that we'll be unprepared when a catastrophe does hit. It's thus a question of how much we should be willing to compromise efficiency for speed, and there's no way to resolve this question without knowing about the other threats we face and how they compare to the threat created by unrestrained technological growth. We both agree that there can be too many or too few restraints, but to optimize our intuitions about what the best balance is, we need more information about the threats and how they compare. Hence my quesiton.

• Answer:

  If the climate change is anthropogenic, then the best thing we can do is stop burning things to produce energy. That means accelerating the progress of technology, not slowing it down.