The footprint of humanity: man-made things weigh more than all life on Earth; weight of living biomass reduced by half, says study

For the first time in history, man-made materials are likely to outnumber all life on Earth, scientists said Wednesday in an investigation detailing the “crossover point” at which humanity’s footprint is heavier than that of the natural world.

The weight of roads, buildings and other materials constructed or manufactured doubles roughly every 20 years, and the authors of the research said it currently weighed 1.1 teratonin (1.1 trillion tons).

As humanity has increased its insatiable consumption of natural resources, the weight of living biomass (trees, plants and animals) has been cut in half since the agricultural revolution to only 1 teraton today, according to the study .

Estimating changes in global biomass and artificial mass since 1900, the research showed that the mass of man-made objects accounted for only three percent of the weight of biomass at the beginning of the 20th century.

But since the post-WWII global production boom, manufacturing has increased to the point where humans now produce the equivalent of the weight of every person on Earth each week on average.

2020 likely marked the time when the artificial mass tilted more than biomass, according to the study published in Nature.

“This study provides a kind of ‘big picture’ snapshot of the planet in 2020,” said co-author Ron Milo from the Department of Plant and Environmental Sciences at Israel’s Weizmann Institute of Science.

“We hope that once we have these somewhat shocking numbers before our eyes, we can as a species take responsibility.”

Based on a large amount of industrial and ecological data, the study estimated that human production represents approximately 30 gigatons per year.

At the current growth rate, artificial material is likely to weigh up to three teratonins by 2040.

At the same time, the overall biomass is declining, mainly due to deforestation and changes in land use that give way to intensive agriculture.

Buildings and roads account for most of the man-made mass, and various construction trends, including the shift from brick to concrete in construction in the mid-1950s, contributed to the accelerating accumulation of weight.

Lead author Emily Elhacham told AFP that the study provides an indication of humanity’s enormous impact on the natural world.

“We can no longer deny our central role in the natural world,” he said. “We are already an important player and that carries a shared responsibility.”

Source