2011-05-27 10:06:37Economist articles
Andy S

skucea@telus...
66.183.183.187

There are two articles in this week's Economist that are worth reading

Welcome to the Anthropocene

A man-made world

The first two paragraphs of the first article:

THE Earth is a big thing; if you divided it up evenly among its 7 billion inhabitants, they would get almost 1 trillion tonnes each. To think that the workings of so vast an entity could be lastingly changed by a species that has been scampering across its surface for less than 1% of 1% of its history seems, on the face of it, absurd. But it is not. Humans have become a force of nature reshaping the planet on a geological scale—but at a far-faster-than-geological speed.

A single engineering project, the Syncrude mine in the Athabasca tar sands, involves moving 30 billion tonnes of earth—twice the amount of sediment that flows down all the rivers in the world in a year. That sediment flow itself, meanwhile, is shrinking; almost 50,000 large dams have over the past half- century cut the flow by nearly a fifth. That is one reason why the Earth’s deltas, home to hundreds of millions of people, are eroding away faster than they can be replenished.

I was astonished to read that claim about the volume of sediments moved in the iar sands compared to all the world's rivers. It's nice to see that they avoid the term "oil sands", incidentally.

 

2011-06-12 07:25:45
Andy S

skucea@telus...
66.183.188.172

Here's a comment from the Economist about a reader's letter concerning the first paragraph I quoted above

We were also pulled up over our calculation that if you divide the Earth up “evenly among its 7 billion inhabitants, they would get almost 1 trillion tonnes each”. Marek Zreda, a resident of Tucson, believes this is misleading, because “Humans inhabit the surface only. Dividing the land area (149 million square km) by the number of people (7 billion) gives about 2 hectares for each person. Take away wasteland, which amounts to roughly half of the land area, gives approximately 1 hectare per person”. Mr Zreda can easily imagine “trashing my hectare. Give me shoes, I can do it in a decade; give me a shovel, it will take a year. And give me a tractor, I will do it in a day.”