Scientists warn that unless humans slow the destruction of Earth’s plant life, civilisation as we know it may become completely unsustainable.
“You can think of the Earth like a battery that has been charged very slowly over billions of years,” said a new study’s lead author, John Schramski, an associate professor in University of Georgia’s College of Engineering.
“The sun’s energy is stored in plants and fossil fuels, but humans are draining energy much faster than it can be replenished.”
Scientists estimate that the Earth contained approximately 1,000 billion tonnes of carbon in living biomass 2,000 years ago. Since that time, humans have reduced that amount by almost half. It is estimated that just over 10% of that biomass was destroyed in just the last century.
“If we don’t reverse this trend, we’ll eventually reach a point where the biomass battery discharges to a level at which Earth can no longer sustain us,” Schramski said.
The paper was published in the Proceedings of the National Academy of Sciences. Its calculations are grounded in the fundamental principles of thermodynamics, a branch of physics concerned with the relationship between heat and mechanical energy.
“I’m not an ardent environmentalist; my training and my scientific work are rooted in thermodynamics,” Schramski said.
“These laws are absolute and incontrovertible; we have a limited amount of biomass energy available on the planet, and once it’s exhausted, there is absolutely nothing to replace it.”