We live within an incredibly dynamic and unique planetary structure; it's actually a remarkable dual body that has created the cycles of life on this planet from which life, and ultimately humanity, arose.
Isaac Asimov's "Tragedy of the Moon" is a collection of non-fiction essays on science. The second chapter, The Triumph of the Moon, points out how the earth-moon dual system created the conditions for evolution of life due to the tidal forces it generated. Asimov also describes how made it possible for the development of mathematics and science; it created the conditions for humans to transcend Earth and conquer space.
This dual system has the effect of not only a dynamic of the two bodies, but creates a planetary stability that allows for a regular seasonal variation that influences the evolution of plant life with strong, repeating cycles of warmth and darkness over the course of the year. These stable and repeating cycles are among the drivers of evolution.
For example, on Mars there are indications that the North Pole was actually warm enough in the recent past for water ice to become liquid. The Mars Reconaissance Orbiter, or MRO, used radar pulses to peer beneath the surface of the ice cap. These data reveal that the ice, just over a mile thick, formed in a succession of layers as the climate alternated between warm and cold.
Our planet avoids mood swings like this in part because its spin is stabilized by a massive moon. Mars' spin is not, so it can really wobble, with the pole tilting toward the sun for long periods. New observations by the MRO spacecraft show that these wobbles can lead to dramatic releases of CO2, and warming periods due to an increase in the greenhouse effect.
The earth itself is also a changing structure, with the landmass expanding on tectonic plates over the millennia, moving and shifting in the seas as they balance out over the globe. This is driven by the molten core of the planet as well as the gravitational tides created by the earth/moon dynamic. This progression is animated here. This has transformed the ecosystems with the creation of massive mountain ranges and subduction zones that create startling and unique life forms and feed the ocean's creatures with upwellings of nutrients. The variety of life thus increased in range and structure.
As life evolved out of the seas while the plants terraformed the atmosphere with oxygen and captured CO2, the system developed the anti-entropic qualities that supports all life. Since its creation 4.5 billion years ago, it has evolved into highly complex ecosystems that interact in tremendous diversity to produce an abundance of life. A brief timeline is here.
We've been here for but a relative nanosecond of earth's history, yet have managed to rapidly bring its ecology to the brink of destruction with the reduction of forest cover, the diminishment of the natural processes and the dumping of formerly sequestered carbon back into the atmosphere. Our failure to understand the uniqueness of our planetary system and its harmonic properties is leading us, and the life that has evolved over millennia, to a bleak conclusion.
Carbon emissions have drastically impacted this planet before. National Geographic recently ran a report, “World Without Ice,” on a period 56 million years ago when, relatively suddenly, huge amounts of carbon flooded the oceans and atmosphere -- about the equivalent amount, scientists suggest, to “the total carbon now estimated to be locked up in fossil fuel deposits” on this planet. The Earth heated up drastically, turning life upside down. This interval of global warming that scientists call the Paleocene-Eocene Thermal Maximum lasted 150,000 years before Earth reestablished its equilibrium, with different ecosystems and species in place.
If we can move swiftly to understand these living systems and work within them, perhaps this conclusion isn't inevitable. Otherwise, as the article states, tens of millions of years from now, whatever becomes of humanity, the whole pattern of life on Earth may be radically different from what it would otherwise have been—simply because of the way we powered our lives for a few centuries.