Some brief thoughts on Earth Day (because I have a ton of other stuff to do)
So, today is Earth Day: a day to celebrate our lovely pale blue dot, and in order to mobilise ourselves, a call to action to stop it getting wrecked. As Phil Plait mentions on his blog (go there, there's a fantastic video/animation from orbit), there will inevitably be a slew of articles and blog posts bemoaning the mess we've made, and how we really need to get our act together and sort out greenhouse gas emissions, pollution, and all that sort of thing.
And yes, we have undoubtedly caused a lot of destruction all over the place, from shocking habitat loss to a slow warming of the entire planet; but I too would rather not dwell on the negatives. I am reminded of an article I read the other day in New Scientist (from last June - I'm actually that far behind), which discusses the possible formal classification of our current era as the Anthropocene, i.e. a geological age in which we are the principal instigators of planet-wide change. The point of the article is not, however, to focus on the pain and pollution us pesky primates permeate, but to point out the fact that this kind of large scale change is actually a bit of an achievement. The Anthropocene has been a long time coming, not just the result of recent increased fossil fuel use or land development - we have been clearing flora and decimating the fauna for about as long as we have been human - and in those few hundred thousand years we have made a significant and measurable effect on almost all areas of the planet.
Putting aside the fact that many of the changes are most certainly detrimental (species extinction and the rise of precarious monocultures, and all that), this is a remarkable thing to have done. This planet is huge: we have built over only a small fraction of its surface, excavated a tiny proportion of its interior, and have barely begun to explore the vast depths of the oceans... and yet we are capable of altering it on a large scale, without even trying. With not even a hint of deliberate terraforming, we have made alterations that nature alone would never have done, making large tracts of land more suited to our habitation or exploitation. With inevitable population growth and advances in technology, and the prospect of geo-engineering looming, this will only become more pronounced.
Now of course I'm not saying that our apparent destructiveness is a wondrous thing to be celebrated: but it is rather impressive. The main point of the New Scientist article - with which I am inclined to agree - is that this shows the awesome potential we as a species have, for large scale alterations to an entire planet. We have been changing the environment since we first started hunting mammoths or rotating crops, but we now wield more power than ever before in terms of our ability to shape the future of life on Earth (for better or worse) - which is something which we really need to face in the coming years.
The upside of all of this (other than my usual awe at humanity's grandiose achievements) is that with this power, we have the potential to start doing things properly. Maybe not yet, but soon, we will likely have both the technology and the motivation to use our innovative and progressive nature for the good of the planet, limiting the damage we do, as well as making it a safer and more stable place to live (nature doesn't exactly have a good track record at not killing us).
Or if all else fails, our experience of making drastic and permanent changes to the operation of an entire world will be useful when we finally go beyond our Earthly cradle and start colonising and terraforming other planets.