Nature: man-made mass surpasses global living biomass

The cumulative mass of artificial materials produced by humans has surpassed the total mass of living creatures on Earth for the first time in history. The analysis proposed that mankind is churning out buildings, roads, and plastic, whose weekly production weighs more than the entire population of the world.

A research finding has been published in the Nature Magazine by Dr. Ron Milo and his team at Weizmann Institute of Science in Israel, suggesting that the human-made mass has exceeded the overall living biomass on Earth for the first time, which approximately equals 1.1 trillion tons.

Dr. Milo and his team made estimates on the global biomass and the total man-made mass from the year 1900 to quantify the impact of human activities on the planet. Biomass was calculated through literature studies, remote satellite monitoring and modeling. Man-made mass was defined as solid inanimate object created by humans. Food or livestock raised by men were considered as biomass while timber was filed under man-made mass.

The findings showed that in 1900, the entire man-made mass on Earth was merely 3% of biomass. But since then, the amount of human-made mass almost has doubled every two decades on the back of a dramatic increase of infrastructure such as buildings, roads, and machines. The cumulative mass of structures and roads built by human this year stood at 1.1 trillion tons, far surpassing the total mass of all trees on the planet, which hovers around 900 billion tons. At around eight billion tons, the mass of plastic was almost twice the amount of all animals on Earth, which weigh four billion tons.

Wastes created by humans, however, were not counted in the analysis. With the amount of trash that were not incinerated or recycled taken into account, the total amount of man-made mass would have already exceeded the global biomass in 2013.

The researchers estimated that should the current trend go on, the human-made mass will reach the mark of 3 trillion tons by 2040. “The quantification of the human enterprise gives a symbolic characterization of the human-induced epoch of the Anthropocene,” said Dr. Milo, hoping that the shocking result should prompt people to act more responsibly.


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