Anthropocene: human-made materials now weigh as much as all living biomass, say scientists


The science-fiction scenario of an engineered planet is already here.

Our deficiencies have always driven us, even among our distant ancestors, back in the last Ice Age. Having neither the speed and strength to hunt large prey, nor sharp teeth and claws to tear flesh, we improvised spears, flint knives, scrapers. Lacking a thick pelt, we took the fur of other animals. As the ice receded, we devised more means of survival and comfort – stone dwellings, ploughs, wheeled vehicles. All these inventions allowed small oases of civilisation to be wrested from a natural wilderness that seemed endless.

The idea of a natural world that dwarfed humanity and its creations long persisted, even into modern times – only to run, lately, into concerns that climate was changing, and species were dying through our actions. How could that be, with us so small, and nature so large?

Now a new study in Nature by a team of scientists from the Weizmann Institute in Israel upends that perspective. Our constructions have now – indeed, spookily, just this year – attained the same mass as that of all living organisms on Earth. The human enterprise is growing fast, too, while nature keeps shrinking. The science-fiction scenario of an engineered planet is already here.

It seems a simple comparison, and yet is fiendishly difficult in practice. But this team has practice in dealing with such impossible challenges. A couple of years ago they worked out the first part of the equation, the mass of all life on Earth – including that of all the fish in the sea, microbes in the soil, trees on land, birds in the air and much more besides. Earth’s biosphere now weighs a little less than 1.2 trillion tonnes (of dry mass, not counting water), trees on land making up most of it. It was something like double that before humans started clearing forests – and it is still diminishing.

Now, the team has delved into the statistics of industrial production and mass flows of all kinds, and reconstructed the growth, from the beginning of the 20th century, of what they call “anthropogenic mass”. This is all the things we build – houses, cars, roads, aeroplanes and myriad other things. The pattern they found was strikingly different. The stuff we build totted up to something like 35 billion tonnes in the year 1900, rising to be roughly double that by the middle of the 20th century. Then, that burst of prosperity after the second world war, termed the Great Acceleration, and our stuff increased several-fold to a little over half a trillion tonnes by the end of the century. In the past 20 years it has doubled again, to be equivalent to, this year, the mass of all living things. In coming years, the living world will be far outweighed – threefold by 2040, they say, if current trends hold.[…]

Continue reading: Anthropocene: human-made materials now weigh as much as all living biomass, say scientists

More: https://www.sciencemag.org/news/2020/12/human-stuff-now-outweighs-all-life-earth?

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About agogo22

Director of Manchester School of Samba at http://www.sambaman.org.uk
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