One must know one's limits

BRT did a post back in 2014 titled The 1st Law, depicting, IMHO, the most important law in science (The 1st law of Thermodynamics - conservation of energy) stating that energy can neither be created or destroyed, only transformed, a law that supports a new study regarding the limits of earth's resources and what it means to man's survival as we move further into the 21st century. 

Chemical energy is stored in plants, or biomass, which is used for food and fuel, but which is also destroyed to make room for agriculture and expanding cities.

Scientists estimate that the Earth contained approximately 1,000 billion tons 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 percent 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.

Working with James H. Brown from the University of New Mexico, Schramski and UGA's David Gattie, an associate professor in the College of Engineering, show that the vast majority of losses come from deforestation, hastened by the advent of large-scale mechanized farming and the need to feed a rapidly growing population. As more biomass is destroyed, the planet has less stored energy, which it needs to maintain Earth's complex food webs and biogeochemical balances.

"As the planet becomes less hospitable and more people depend on fewer available energy options, their standard of living and very survival will become increasingly vulnerable to fluctuations, such as droughts, disease epidemics and social unrest," Schramski said.

If human beings do not go extinct, and biomass drops below sustainable thresholds, the population will decline drastically, and people will be forced to return to life as hunter-gatherers or simple horticulturalists, according to the paper.

"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."

Overshoot awaits, if we let it.

Today humanity uses the equivalent of 1.5 planets to provide the resources we use and absorb our waste. This means it now takes the Earth one year and six months to regenerate what we use in a year.

Moderate UN scenarios suggest that if current population and consumption trends continue, by the 2030s, we will need the equivalent of two Earths to support us. And of course, we only have one.

"One must know one's limits" - Dirty Harry