Human Technology on Earth Weighs a Massive 30 Trillion Tons

The technosphere includes all the materials and structures that humans create. Education Images/UIG via Getty Images

We're knee-deep in the holidays, which means that a lot of well-intentioned folks are getting on the scale to make sure that gelt candy and those sugar cookies aren't hitting their waistbands too hard. It's bad enough for us eggnog lovers, but Earth has it even worse — the planet has put on roughly 30 trillion tons thanks to humanity.

According to new research by an international team of scientists, the systems and matter that make up the "technosphere," a term coined by paper co-author Peter Haff, have just as much impact on Earth as the atmosphere and biosphere. Geologists and engineers accounted for the gigantic mass of materials — transportation systems, housing, shoes, waste — that humans created and use to stay alive and thrive in the world. But don't mistake the technosphere's contents for just "stuff"; it also encompasses human organizations and the environments that keep society functioning, like farmlands, seafloor excavations, domesticated animals and reservoirs.

This vast sprawl of systems, materials and structures has a mass of about 30 trillion tons, which would mean 10 pounds per square foot (50 kilograms per square meter) if spread evenly over Earth's surface. That's about five times greater than the human biomass it supports, according to the researchers. The authors of the paper also point out that unlike the biosphere, the technosphere isn't doing a great job of recycling its residue layer, which includes waste like landfills and methane in the atmosphere — a problem that has been vexing environmentalists for years.

But there is an upside: The technosphere provides a lot of "technofossils" (think computers, books and smartphones) that can mark eras just as well as biological fossil markers.

"The technosphere may be geologically young," lead author Jan Zalasiewicz says in a press release, "but it is evolving with furious speed, and it has already left a deep imprint on our planet."