A study done by a team of scientists from the Weizmann Institute in Israel have found that the totality of human-made materials is now equivalent to the entire biomass of the Earth which stood at nearly 1.2 trillion tonnes — a number which was also calculated by the same team of scientists two years ago. The study was published in a journal called Nature.
The calculation of Earth’s biomass included only dry mass (no water). All fish in the sea, all trees on land, all birds in the air, microbes in the soil, and much more, figured into the calculation.
Trees on land made up the bulk of Earth’s biomass. The biomass of the Earth was also nearly double the current figure before humans started clearing forests. With human expansion growing it is likely to shrink even further.
For the human-made materials part of the equation, the research team made a deep dive into statistics of industrial productions and mass flows to reconstruct the growth from the 20th century onwards. The calculation included all the things we build like airplanes, cars, roads, houses, etc.
By the end of the 20th century, human-made materials amounted to over half a trillion tonnes while it was just 35 billion tonnes at the start of the century thanks in part to what is termed as the Great Acceleration. That figure then doubled in the last couple of decades, reaching where we are now.
Viewing in terms of ingredients for human-made materials, concrete made up about four-fifths of the materials contributing to the mass, followed by bricks, asphalt, and metal. Plastics weren’t a major contributor but their mass was still greater than all animals on Earth.
If current trends keep up, the research team also estimated that human-made material will be three times the Earth’s biomass by 2040.