“Time Enough for Love”

The earth climate machine is highly complex, like a rain forest or coral reef ecosystem. There are many feedback loops and intricate, nested processes with all sorts of interconnections. Systems like this are capable of absorbing enormous perturbations but they eventually come back to an equilibrium. They may deviate wildly until back-pressures force them to relax back to a stable state, or at least some form of dynamic equilibrium, like a periodic oscillation around some mean. But they eventually come back to some stable condition.

There is some evidence that suggests this is so. The earth climate has changed enormously over Deep Time as we have learned by studying the geologic and fossil records, but it has remained capable of supporting life in pretty much the same conditions that exist today. Sure there have been swings and changes, some quite severe, but there have been no runaway events that have made the planet uninhabitable. Even major changes like ice ages have not led to catastrophe on a global scale. The Earth abides.

We also know the climate system has survived enormous external stresses like continental drift, volcanic episodes, and even major meteoric impacts that have led to mass extinctions, but the overall system soon recovered, albeit at some new equilibrium state. Since we developed an oxygen atmosphere, the planet has been continuously habitable. In fact, life has succeeded in quickly recovering abd populating new environments.

Now this does not mean that human civilization will easily absorb these changes. Climate change, as we experience it now, may alter agricultural patterns, land use, weather change, flooding, droughts, etc. The human response may include famine, mass migration, war, civil unrest and political and social chaos. There may be severe sea level rise, changes in major weather patterns like the monsoon, melting of the icecaps, and vast upheavals in currently stable ecosystems. But the earth will survive, and it will thrive. However, human civilization may not. We know much of North America and Eurasia had very productive ecosystems; tundra, taiga, boreal and deciduous forests and temperate savannas (steppes) until fairly recently, and yet they were under a mile of ice only a few thousand years ago. The planet and life, and even human communities, can absorb an enormous amount of stress and bounce back.

Even Stone Age Man can inflict great changes on the landscape with his fire, megafauna predation and even primitive agriculture. Much of what we consider as ‘wilderness’ is actually the result of tribal land use practices. When the Romans got to Britain, they did not find a vast forest with a few scattered settlements of Druids. They found a population of millions, and more land under cultivation than existed until Victorian times.

The planet’s taken a lot of punishment, and it has not runaway into full-blown chaos. But we also know our civilization depends on corn and soybeans being grown in the Midwest, rice in SE Asia and wheat in the Ukraine. Even a minor and temporary climatic deviation could generate enormous industrial consequences. Not only are we making the world unstable, we are not too resistant to instability ourselves.

But in the worst cases, the researchers found that Earth’s climate leads to chaos. True, mathematical chaos. In a chaotic system, there is no equilibrium and no repeatable patterns. A chaotic climate would have seasons that change wildly from decade to decade (or even year to year). Some years would experience sudden flashes of extreme weather, while others would be completely quiet. Even the average Earth temperature may fluctuate wildly, swinging from cooler to hotter periods in relatively short periods of time. It would become utterly impossible to determine in what direction Earth’s climate is headed.

https://www.livescience.com/humanity-turns-earth-chaotic-climate-system