In my previous post , I addressed the issue of how many people the Earth could support, just as animals. It's a lot of people, double our current population- but we don't want to live like animals. Can the earth support the lifestyle we would prefer? That's a question of resources. Again, I'll use America as a microcosm of the Earth. So what's the first resource environmental activists warn us we're running out of? Clean water is the biggie; all others pale next to that. The common numbers quoted is that the US consumes some 408 billion gallons a day. That's a big, scary number... surely that couldn't be sustained, could it? No, it couldn't- if it were true.
We don't consume 408 billion gallons, we merely use it. What do I mean? Look at your daily life... it takes a lot of water just to wash- yourself, your clothes, your dishes. But you didn't consume that water; you just borrowed it for a few minutes, then opened the drain and put it right back into the environment. (hopefully after being treated first) Water is endlessly recyclable. Yesterday's bath water is returned to the environment and comes back as tomorrow's bath water- that 408 billion gallons isn't a consumption rate, it's the flow rate of a cycle.
But surely we keep some of it, even if only temporarily, right? Sequestered away from the environment? Certainly. In your life, you've ingested thousands of gallons of water in food and drink- depending upon your age, perhaps a hundred thousand pounds of water... how much have you kept? Your body mass, of course. At an average of 150 lbs., that's some 18 gallons. That's all- the rest was returned to the environment, as water vapor in your breath and sweat, and flushed down the toilet. That, plus what you keep in your pipes and water heater (assuming you don't have a flow-through heater), is all you're keeping out of the environment.
And even that ratio is high compared to manufacturing, because the human body is actually composed of water plus some trace elements. All told, it took hundreds of thousand of pounds of water to manufacture your car- virtually all of which was used and returned to the environment, again hopefully after treatment. (We spend tens of millions of dollars enforcing compliance with the Clean Water Act- didn't it ever occur to the government that there's an easier way to ensure compliance? Simply require that their intake pipes be downstream of the output- they'd make damn sure the output was clean then, wouldn't they? But I digress.) But after all that water usage manufacturing that car, how much was kept? The ten pounds or so in the radiator. That's all. We don't dam up the flow of rain on the plains which mainly runs to rivers which runs to oceans who evaporate and rain on the plains... we just divert a small portion of it in a different direction along the way.
So how big is that flow? The Mississippi river discharges an average 12,740 metric tons of fresh water into the ocean per second. The St Lawrence only slightly less. And there are a lot of rivers. Plus underground rivers. Plus billions of tons as clouds and atmospheric water vapor. Many times what we're currently using. I've been speaking so far of just North America; how much water is available for world use? What is easily useable is groundwater and fresh surface water- lakes and rivers. According to Wikipedia , there is 13,000,000 km³ of groundwater and 250,000 km³ of freshwater; a cubic kilometer is one billion metric tons of water.
What's that you say? Despite all my claims, there are genuine shortages out west, aquifer levels dropping, cities and states suing each other over water rights- what do I have to say about that? It's all true- but it doesn't mean the needed water doesn't exist; it merely means that it's not where they need it. You know, the Romans faced that problem a couple millennia ago, and they came up with this bizarre, counterintuitive solution: move the water from where it is to where you want it. We've proven we can do it with the vast oil pipelines around the world. The only reason they don't do it out west is economics; at this moment, it's cheaper to just dig the wells deeper and sue your neighbor over the surface water within arm's reach.
So to make a long story short, (I know, too late!), how many people do I think can the Earth sustain, at our level of civilization? To start with, the land area of the earth is 148,940,000 square kilometers; let's say only a third of that is comfortably usable. As to how to live on that land, I look to Europe- they've been civilized a long time; I'll presume they're doing things in a more or less sustainable way. The have a nice energy mix; France, for example, gets 80% of their electricity from non-polluting nuclear plants. Belgium, despite being sustainable, (as I noted in The Myth of Overpopulation Part 2 , they're a net food exporter) has an excessive population density. France, being the flattest European country, is perhaps not representative of the diverse geography of the world. So let's look at Germany- they have mountains and forests with wild animals, ocean front beaches, and farms in-between. Germany has a population density of 230/km; multiplied by a third of the land area mentioned above, that's 11.4 billion people. That's without altering our lifestyle, other than actually enforcing anti-pollution laws and using existing green energy techniques. If we went vegetarian, or nearly so, did more public transportation, all the obvious things, we could double that and still have a comfortable lifestyle.
What's your estimate?
Showing posts with label sustainability. Show all posts
Showing posts with label sustainability. Show all posts
Thursday, May 14, 2009
Sustainability
This is an offshoot of the discussion on overpopulationThe Myth of Overpopulation Part 2 The topic of sustainability was raised- this is a big concern of environmentalists. The problem is that experts with doctorates differ wildly about what population level is sustainable; some say as few as 2 billion, others upwards of 50 billion. How's a poor layman to know what is right when the experts disagree?
The first step is to realize that experts are people, too, and so can become attached to pet theories, fail to consider alternatives. Their specializations sometimes induce tunnel vision- this phenomenon is so well known that it spawned an aphorism: "an expert has mastered his discipline from B to Z and forgotten A". This is where common sense and a pocket calculator come in. If you remember your college algebra, I can show you a syllogism that proves 2 = 1; but you don't need a doctorate in math to know that's wrong, you only need your common sense. As Bob Dylan said, you don't have to be a weatherman to know which way the wind blows.
Ok, the first thing to remember is that this is a closed system; other than a couple tons of metal we left on the Moon, what happens on Earth, stays on Earth. The second thing to remember is that we do not exist apart from the environment; we are part of it. The third thing to remember is that life is persistent, it expands to fill the niches. If we, as animals, did not exist, that would not mean fewer total animals on Earth, it would mean other animals would be born to eat what we're not eating- so the actual question is, how much animal life is sustainable on Earth?
An equally hard question. Let's look just at North America, a good microcosm of the whole. A few centuries ago, it was in a natural state, in that the people living here were, speaking only environmentally, living as animals- their art, music, and complex culture was not polluting or depleting the environment. How much animal life was being naturally sustained then? Still too complex; let's take another microcosm, an animal we know something about: the North American Bison, or buffalo.
Experts say there were between 30 and 60 million buffalo; split the difference and call it 45 million. Buffalos run upwards of 2,200 lbs. each; round that down to an even ton. That gives us some 90 billion pounds of animals- what's that in human terms? The average human runs 150 lbs.; that gives us 600 million people! Yeah, yeah, that's overly simplistic, it's not a pound for pound ratio, yada yada. But it's not a meaningless number, either- it really was 90 billion pounds of hot, pulsing mammal flesh, and that was only a single species, ignoring deer and moose and elk and beaver and a couple hundred million squirrels and a couple billion birds and a few trillion insects, all sustained without digging a single well or plowing a single furrow!
Of course, directly replacing the buffalo would mean living like a buffalo- there's a visual for you, 600 million naked vegetarians! People won't live like that- I want my MTV! We have a civilization to maintain, and that takes a lot of resources- resources that we're running out of. Or are we?
Next: Resources.
The first step is to realize that experts are people, too, and so can become attached to pet theories, fail to consider alternatives. Their specializations sometimes induce tunnel vision- this phenomenon is so well known that it spawned an aphorism: "an expert has mastered his discipline from B to Z and forgotten A". This is where common sense and a pocket calculator come in. If you remember your college algebra, I can show you a syllogism that proves 2 = 1; but you don't need a doctorate in math to know that's wrong, you only need your common sense. As Bob Dylan said, you don't have to be a weatherman to know which way the wind blows.
Ok, the first thing to remember is that this is a closed system; other than a couple tons of metal we left on the Moon, what happens on Earth, stays on Earth. The second thing to remember is that we do not exist apart from the environment; we are part of it. The third thing to remember is that life is persistent, it expands to fill the niches. If we, as animals, did not exist, that would not mean fewer total animals on Earth, it would mean other animals would be born to eat what we're not eating- so the actual question is, how much animal life is sustainable on Earth?
An equally hard question. Let's look just at North America, a good microcosm of the whole. A few centuries ago, it was in a natural state, in that the people living here were, speaking only environmentally, living as animals- their art, music, and complex culture was not polluting or depleting the environment. How much animal life was being naturally sustained then? Still too complex; let's take another microcosm, an animal we know something about: the North American Bison, or buffalo.
Experts say there were between 30 and 60 million buffalo; split the difference and call it 45 million. Buffalos run upwards of 2,200 lbs. each; round that down to an even ton. That gives us some 90 billion pounds of animals- what's that in human terms? The average human runs 150 lbs.; that gives us 600 million people! Yeah, yeah, that's overly simplistic, it's not a pound for pound ratio, yada yada. But it's not a meaningless number, either- it really was 90 billion pounds of hot, pulsing mammal flesh, and that was only a single species, ignoring deer and moose and elk and beaver and a couple hundred million squirrels and a couple billion birds and a few trillion insects, all sustained without digging a single well or plowing a single furrow!
Of course, directly replacing the buffalo would mean living like a buffalo- there's a visual for you, 600 million naked vegetarians! People won't live like that- I want my MTV! We have a civilization to maintain, and that takes a lot of resources- resources that we're running out of. Or are we?
Next: Resources.
Subscribe to:
Posts (Atom)