Scientists to Earth: Prepare to Abandon Planet
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Earth First! Now we’ll trash the other planets. There are other planets, right? (Photo by Gideon Wright/Flickr)
Two major scientific studies out this week agree that it may well be time to include other planets in your future relocation plans. Because we have just about finished trashing this one. One study says that of nine “planetary boundaries,” which is to say boundaries between inhabitable and uninhabitable, human activity has already wrecked four. The other finds an implacable rise in the number of mass dyings of animals, of such magnitude that they “can reshape the ecological and evolutionary trajectories of life on Earth.” And, need we specify, not in a good way. Let’s see what these studies say, and then consider what we should make of what they say.
Five years ago, a group of scientists laid out a series of benchmarks for assessing the damage we’ve done to the web of life. They established nine “boundaries” that define a “safe operating space” for humanity — theoretical limits to destruction that we exceed at our peril. They were: the rate at which species are becoming extinct; the rate of deforestation; the level of carbon dioxide in the atmosphere; the flow of nutrients from fertilizer into the oceans; ozone depletion; freshwater use; ocean acidification; atmospheric aerosol pollution; and the introduction of exotic chemicals and modified organisms.
The purpose of the current paper was to refine the boundaries concept and to see how we are doing. It concluded that we have already trampled the first four boundaries and are endangering the remainder. “Human activities are destabilizing the global environment,” said the paper’s lead author, Will Steffen of the Australian National University. When exactly the system will become destabilized, putting the entire human population in dire peril, cannot be estimated with certainty but Steffen sees it happening, on the current course, in a time frame of “decades out to a century.”
Take that as the good news: the bad news is that MMEs — mass mortality events — are on the rise around the world. They key word here is mass: we’re talking about events in which at least a billion animals die, more than 90% of an existing population, leaving 700 million tons of corpses. Believe it or not, there have been 727 such events recorded since 1940. And a survey of those events finds that they are increasing in frequency for birds, marine invertebrates and fish, while remaining constant for mammals and decreasing for reptiles and amphibians.
What are we to make of such science? Most of our brethren and, um, cistern will ignore it, as they do any science not headlined “miracle weight loss without effort.” Some of us, a decided but growing minority, will take it as further evidence of a coming collapse of the industrial age. And of that minority, a minority (Guy McPherson being a prominent example) believes that what is coming is an extinction of the human race.
I will not go that far. Not because I think I have superior scientific knowledge (than Dr. McPherson? Get out!) or can prove one case or another, but for two reasons that satisfy me.
- It is not useful to me to believe that all humans are going to die, or the planet is going to fry, or the sun is going to explode. So I refuse to believe it. Now, that may be as maddening in its way as the refusal of right wingers to believe in climate change despite all evidence to the contrary, simply because they don’t want to. But there is a difference. I don’t deny the possibility that Dr. McPherson et al may be right; I just prefer to act and plan and think while focussed on the possibility they may be wrong.
- It would be well to keep in mind, it seems to me, how wrong the scientists have been about the effects of climate change. They have consistently underestimated the speed and severity of its onset. It seems reasonable to expect them to be wrong in the future, as they try to quantify a staggering array of variables, and it does not seem reasonable to expect them to be wrong only on one side of the ledger. The two things humans have consistently underestimated is the amount of harm they are doing to natural systems, and the power of those systems to recover if we just quit doing the harm.
But all of this — the power to harm, the power to recover, the power to understand — has to bow down at present before the awesome power of stupidity in a culture that, having been told clearly and repeatedly that it is destroying the foundations of its existence, continues to do so.
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