Weep Not for Earth

Heaven lasts long, and Earth abides.

-Lao Tzu

I occasionally hear statements of this sort: "We're trashing the planet", "We're ruining the environment", and "The Earth would be better off without us". Others have pointed out flaws with these positions, but I find it useful to remind myself just how much catastrophe the Earth has borne in it's 4.5 billion year lifetime. Here are just a few highlights:

• The Great Dying occurred 251.4 million years ago. New research suggests an unprecedented series of volcanic eruptions massively altered the environment. The climate changed severely, the oceans acidified, ash blocked out the sun. Magma contacted huge coal deposits in Siberia. What happened next may be similar to the disaster that befell Centralia, Pennsylvania; but on an astronomical scale. Coal, burning underground, may have put as much as 3 trillion tons of carbon into the atmosphere. To put that into perspective, in 2008 all the fuel burned worldwide released under 30 billion tons of carbon (source). 96% of all marine species went extinct, plus 70% of all land species.
• 65.5 million years ago the Cretaceous-Tertiary extinction event happened. The scientific consensus is that an asteroid at least 6 miles across impacted in what is now the Gulf of Mexico. Large parts of the planet were roasted by the 100,000,000 megaton equivalent energy release. Later, the Earth was shrouded in ash and dust, cooling and then starving what few organisms survived the impact. 75% of all species went extinct.
• More recently and on a smaller scale, a swarm of cometary debris may have impacted present day North America about 13,000 years ago. If there were people living in North America when this occurred, they would have witnessed the closest thing to nuclear holocaust ever seen by human eyes. Thousands of explosions, each comparable to a hydrogen bomb, would have occurred as the ice and rock fragments either impacted the ground or vaporized in the atmosphere. Ejecta from this disaster absorbed or reflected the sun's radiation and prolonged the last ice age.

It takes a lot to actually hurt our planet. Short of astronomical phenomena or advanced technology, Earth itself is quite safe. We, on the other hand, are not. It's our job to remember that distinction, so we know what it is we are fighting for.