Now, I have a lot to say in response to that argument (It’s basically another way to abdicate responsibility. It’s on the same level as saying “God will end the world soon and I’ll go to heaven, so really we should put more effort into prayer”), but that’s not what I want to talk about here.
For this post, I want to go into what it will take to colonize space.
(apologies for the archaic gender roles)
First, we need to think about food and water. Even if we assume that we can somehow get large amounts of water off the planet, there are limits to how much can be brought, and it’s simply not possible to generate more water out of nothing. Water, or the resources needed to make it, might be extracted from the destination planet or from planets/asteroids encountered en route for longer trips, but even so, we’ll need to be able to use water as efficiently as possible, so we’ll have to perfect the art of reconstituting human waste into potable water, and for longer trips, we’ll probably want to be able to collect the water from deceased human bodies as well.
We will also need to be able to grow our own food since, as with water, we can’t bring everything we’d need. Growing food takes water, and so once again, we’ll need to perfect the art of growing as much food as possible with as little water as possible. Since we’ll be doing it indoors (even if we DO figure out how to terraform, it’ll take ages to do, and until then, we’ll have to be inside), we’ll need to perfect the process of growing food indoors, without reliable sunlight or weather.
You can probably see where I’m going with this. In adapting to climate change, we’re going to need to be able to do more with less water as droughts become less common and as, in the interim, fossil fuel companies continue to poison rivers, lakes, and aquifers. We’re also not going to be able to rely on seasonal weather patterns anymore, so we’re going to have to move a significant portion of our agriculture indoors, which means we’ll have to be able to produce at least as much food indoors as we did in the days of midwestern mega-farms.
Energy will also be a concern. Fuel is heavy, so the best way to do it, if we can, is figure out how to use solar power to do most of the heavy lifting, and maybe use methane generation as part of the food/waste reconstitution process. We’ll also have to do everything that requires power as efficiently as possible so that power can be spared for essential processes and stored in case of emergencies.
We’ll also have to learn how to build advanced machinery that’s easy to repair, and ideally that can be repaired with readily available materials, like bioplastic made from plants that are grown on board.
In summary, in order to “leave this doomed planet”, we’ll need renewable energy, water efficiency, energy efficiency, sustainable, indoor farming, and technology that’s redundant and repairable enough to keep functioning through unexpected disasters. So, to all you would-be space colonists, welcome to the fight!