Tipping Points

There's an idea in climate science called a 'tipping point': A threshold where any further change to CO2 levels, no matter how small, will have dramatic effects.

These effects may range from the collapse of entire ecosystems (including ones we are dependant on) to effects which lead to a startling increase in greenhouse gases (which may, in turn, trigger further tipping points).

An example is where climate change reduces rainfall over the Amazon rainforest to a point where massive forest fires occur. The resulting deforestation effects the local climate and reduces the rainfall further, more forest fires result, and the cycle continues. The end result is a devastated ecosystem, lose of an enormous carbon sink (the rainforest absorbs a significant amount of CO2) and the release of vast quantities of greenhouse gases [GHGs] back into the atmosphere. Not good.

There are a number of potential tipping points known to climate science, like the loss of Arctic Sea ice (which currently reflects heat back into space), and loss of permafrost (which would release more GHGs). It's believed there are others we have no idea about yet.

This is why there's so much talk about keeping global warming down to a 2 degree centigrade rise: It's thought that, beyond this level, the risks of hitting one of these tipping points increases greatly.

So, if you feel comfortable with the idea of an almost imperceptible rise in temperature that 'only' effects a bunch of people on the other side of the world, think again. There are tipping points out there, just waiting for us trigger them. That's when things get really messy....