In various scientific areas of investigation researchers have long known that sometimes a chemical or even a mechanical interaction will accelerate rapidly of its own accord. Most often, this is the result of some element of the process becoming energized by an action or interaction within the process itself. Hence the term, 'feedback'. For instance, let's say a machine has a problem with harmonic vibration. This can happen in high-intensity engines with many parts moving at furious speeds in relationship to each other. So, a very high rpm shaft develops a vibration that has a harmonic aspect to it, and it sets up vibrations at other levels in addition to the simple one that is the source of the problem. And, as this process develops the secondary and tertiary vibrations begin to cause a break-down in the tolerances of the bearings and pretty soon the machine is vibrating so badly that it will likely tear itself apart if it isn't shut-down. It's the old, 'one thing leads to another.....and another' thing at work.
With regard to climate change and the phenomenon of global warming--still regarded as a myth and conspiracy by the likes of Michele Bachmann and Ric Perry--scientists have discovered a number or elements in the overall process that have feedback potential. A good example is that of changes brought about by the shrinking of the polar ice in the arctic. Instead of a white sheet of ice--which reflects the heat of the sun very well, thereby preserving the cold temps of the ocean beneath it--as the ice retreats, it is replaced by dark green sea water and that accepts and absorbs the energy from the sun much more readily......so the warming of that region speeds up accordingly. Voila! A feedback cycle.
Another example--a more powerful one which is much less predictable--is that of methyl hydrates, frozen methane gas. It exists in vast deposits, both on the ocean floor, and in the tundra regions of the arctic north. As the ocean continues to get warmer, and as the perma-frost in the tundra melts, incalculable amounts of methane are being released. But, despite not being able to clearly monitor or calculate how much is becoming gaseous methane and escaping into the earth's atmosphere, scientists do know--beyond any doubt--that the amount is very great, and that methane is a 'hot-house' gas with even more ability to warm the atmosphere than carbon-dioxide. This has the potential to become a runaway feedback cycle and completely invalidate all the scientific calculations about the speed with which global warming is happening. It's not magic, but the results could seem magical in terms of how surprisingly fast the entire process could become. (Click on the title of this piece to read an article on this phenomenon.)
There are other feedback cycles in this process. Years ago it came to my attention that the vast majority of photosynthesis is performed NOT by the plants of our planet, but by blue-green algae in the oceans. The forests and jungles perform only about 25% of what is required for the maintenance of life on Earth. So, if the blue-green algae in our oceans stop producing oxygen...and up-taking carbon-dioxide....to put it scientifically....we are SO screwed. If the oceans continue to get warmer, some scientists think this is exactly what might happen. But, not to worry, they're clearly making all this up just so they'll have jobs, in the non-existent future.
I hope that you find all of this not merely 'scary'. That would accomplish NOTHING. What I really am hoping you will do is throw the weight of your opinion and your energy behind the fact that we need to stop lolly-gagging and insist on action across the board to do the only sensible thing intelligent beings should do......CHANGE WHAT WE HAVE BEEN DOING TO CAUSE OUR OWN DEMISE.