If one thinks about it, much of life as we know it depends upon the white poles. The temperature of Earth depends upon said polar regions. The poles, as long as they are covered with snow, reflect much light into space. That’s why the poles are white: because they are reflectors. Remove the poles’ whiteness, and Earth will absorb much more sunlight, her average temperature will shoot up. This is already happening, the effect is self-feeding, and, thus, nonlinear. This exponential effect is already apparent in two ways:
- the temperatures in the Arctic have climbed at a rate up to five or even ten times faster than anywhere else (as local whiteness, albedo, disappear).
- at some point, one expects the global temperature to do the same, and exit the linear regime. This is exactly what one has observed in the last couple of years. Also the main warming system of the biosphere, El Nino, seems to be running for the second year in a row (it used to run only every seven years, or so).
So we are leaving the linear rise in the greenhouse effects, to enter a faster, nonlinear phase.
This should not surprise anybody. Look at the CO2 graph, superimposed on a picture of Earth’s atmosphere (contemplate how thin it is!) The CO2 concentration is already massively nonlinear, and it is the main driver of climate, thus climate’s behavior can only be so.
Reality is even worse, as the graph above does not take into account other gases which have an even stronger greenhouse effect, individually than CO2, sometimes by a factor of thousands of times, per unit of mass, and which are all man-made. Nor CH4, methane, related to cattle bowels and decaying permafrost or warmed-up, exploding methane clathrates, in the preceding graph, although its greenhouse effect is huge.
CO2 concentrations are the highest since Homo Sapiens evolved. Also the change of greenhouse gas concentrations is the most brutal ever since at least 17 million years ago (when the Columbia LIP, Large Igneous Province, occurred, and, presumably, vast amounts of CO2 were injected in the atmosphere).
During the last high CO2 concentration, 110,000 years ago, although said concentrations were much less than now, average temperature got a bit higher than now (one Celsius) Sea level was at least seven meters higher.
The nonlinear collapse of whiteness on Earth (“Earth albedo) is apparent in the sudden collapse of the ice-covered regions in both the Arctic and the Antarctic, this last season 2016–2017. Clearly, linear graphs can’t be extended anymore, as far as spaceship Earth is concerned. Tickling the dragon by the tail works for a while, until one gets scorched!