A planet's worth of human-made things has been weighed

A new reporthas calculated the total mass of all the technology humans have produced, everything from buildingsto cars and computers, and found it is an astounding 30 trillion tons. That is more than the total amount of living matter on Earth. It shows the sheer magnitude of the human impact on our planet, which is still growing.

An international team led by the University of Leicester in England added up the mass of all our houses, factories, skyscrapers, right down to smartphones and ballpoint pens, as well as waste material in landfills, to come up with the staggering number that represents a mass of more than 50 kilograms for every square metre of Earth's surface.

By contrast, the total amount of living matter, including people, plants, animals, insects and bacteria is estimated to be around 4 trillion tons of carbon. Our technology and everything that comes with it is literally larger than life.

This huge conglomeration of human artifacts is called the technosphere because it is now so large, it compares with other large systems on the planet, such as the biosphere, atmosphere and hydrosphere (water). And like those other spheres, it is dynamic, consumes energy and resources, produces waste, and is growing with time. Our technology is a super-organism that competes with the biosphere for resources, and is winning that competition by taking over the surface of the planet.

Living organisms are very good at recycling. When a tree falls in the forest, other creatures in the soil take advantage of a new food source and decompose it, returning it to the soil, while new trees grow in its place. The web of life is in a constant state of renewal and finds a balance in an ecosystem where no one species can become overpopulated for too long. If it does, all the resources are consumed and that species suffers a mass die-off.

The technosphere is not so good at recycling. Our disposable society and desire to have the latest, newest products has created enormous landfills stuffed with billions of tons of old computers, building materials, household goods, as well as refuse we have dumped in the oceans and even junk in space. Meanwhile, our technosphere continues to gobble up new resources to keep up with a growing human population and a growing demand for anything new.

The biosphere is also adaptable to changes in the environment caused by volcanic eruptions, meteor impacts, or climate change, which can wreak havoc on some species, but new species take over the new conditions the way mammals dominated after the dinosaurs went extinct. Earth has been through several major extinctions in its history, where up to 95 per centof life on land and in the seas has been wiped out. But life always comes back. However, that new life is different from the life that was there before, and the old life ends up as a dark line in layers of rock.

Our growing pile of technological refuse has the authors wondering how our remains will be preserved in the distant future. The geological record is filled with fossilized bones, feathers and teeth of creatures from the past who no longer exist. Those past eras of life on Earth have been compressed over time into thin layers of rock that paleontologists and archaeologists can pick through to reconstruct the past.

What kind of layer will the technosphere leave behind?

Imagine archaeologists, or perhaps visitors from another world, millions of years from now, digging down to find a layer in the Earth that is unlike all the others. This layer will be filled with millions of bits of plastic, glass, coins, jewelry, radioactive materials, patterns of roads, and billions of other "techofossils" that outnumber the biological fossils found in the layers below. And scattered among the debris will be countless bones of creatures that stood on two legs and occupied every part of the planet's surface.

This new view of ourselves as a super-organism that is eating up and burning up everything in sight, while leaving behind a trail of trash is a wake-up call. How long can it grow before it runs out of resources and suffers a mass die-off?

One thing the technosphere has that other natural mega-systems do notis human knowledge. We have the insight to see ourselves and avert disaster by careful management of our resources and impact on the rest of the world. In other words, we have foresight.

The question is, will we use it?