What it is ain't exactly clear.
Time Magazine got around to a cover story with a picture of a polar bear on a melting ice field this week. They have the words "be worried - be very worried" to add to the urgency.
The article is nothing new, assuming you have been paying attention - we have been doing a lot of things to mother earth without knowing what the ultimate effects will be, not unlike our current faith and a prayer approach to genetic or bio engineering or other tweaking of complex systems without adequate predictive models. We can't really test everything, our models may be more or less accurate, but in the name of progress we plod on.
Ilya Prigogine who was awarded the 1977 Nobel Prize for his work on the thermodynamics of nonequilibrium systems talks about a bifurcation point. effects may be slow until a certain tipping point and then a drastic change starts to occur very rapidly.
It might help to think about heating water in understanding a bifurcation point - not much happens as you raise the temperature to 100 C but then all of sudden voila it starts to boil. The average temperature of the earth has risen about a degree in a hundred years - we tend to think no problem it's only one degree - unless we are near some bifurcation point in this complex planet we live on. Another tenth of a degree might kill off the toads, or the polar bears, some flowers, some species of fish or maybe there is some complex system interaction that will end up killing us....nobody knows. At some point people may want to pay attention to the proverbial canary in the coal mine.
Besides not knowing what bifurcation points we may be closing in on, the non-linearity is where we are starting to run into a problem with good old mother earth. We've been putting carbon dioxide into the atmosphere at an unprecedented rate as our affluent society uses internal combustion engines and coal/gas/oil fired power plants to maintain our standard of living. Carbon dioxide has the effect of trapping heat in our atmosphere, what we call the "greenhouse effect". This isn't completely a bad thing since earth would be a cold and inhospitable place without the heat trapping effect of carbon dioxide.
Things have been going pretty good. We saw a little climate change but nothing to get overly concerned about, at least not to the point of signing up to the Kyoto treaty or anything drastic like cutting consumption of fuel by raising federal minimums for gas mileage.
The problems start to occur when we get just a little too much carbon dioxide in the atmosphere and things go exponential as they say. How much is "a little too much much" you ask?
No one knows but we are running a very risky experiment with the planet to figure it out.
Here's the main points of what's happening in case you haven't been paying attention -
Cars, trucks, power plants and industry have been pouring carbon into the atmosphere causing the greenhouse effect to make the earth a little too much of a greenhouse.
Slight rises in global temperature have caused the polar icecaps, and various glaciers to begin melting. We thought this would be a slow process...turns out we were wrong. Once the glacier ice starts to melt it happens much quicker than we thought.
Ice is a much better reflector of heat from the sun than the ocean. As the ice disappears we have a secondary effect of even more warming as the oceans absorb heat from the sun and warm up.
The disturbance in the ocean temperature impacts our climate. The sinking of colder ocean currents form a heat pump that modulates the weather - warming the earth as the water approaches the poles and cooling it as the currents sink and return to the equatorial regions. Net result - unknown - but it looks like Europe is in for some very cold winters, some places will have unprecedented droughts; not to mention typhoons, hurricanes and other unpleasant weather.
Trees convert carbon dioxide to oxygen...unfortunately for us we have been cutting down the forests like there's no tomorrow.
There are secondary effects due to the decreasing salinity of the oceans, melting of the permafrost which releases methane (another greenhouse gas), tilling land formerly covered by trees (again releasing methane) and the surface warming that occurs as cooling forests are cut down.
The main point is that no one really knows how this all works. The solutions will be complex and not easy. It may mean addressing the afflueza we suffer from in the U.S. and end up downsizing in a big way - from our houses, to our commuting distances, to our gas guzzling cars and eventually population migrations from our air conditioned desert oases ala Las Vegas to more hospital climes. Be nice to Canadians.
Economics will play a major role. The system is somewhat self correcting as we see rising costs of energy.
We have to act globally.
Carbon emissions trading is probably the best bet. These exchanges have been put into place in the E.U. and various regions of the U.S.
It would be relatively simple for the government to implement an individual or household based carbon emissions exchange. We start the program by giving each person an allocation to emit a certain amount of carbon into the atmosphere. If you plant a tree you might have one credit. If I drive my old fuel inefficient pickup I might want to buy your credit. We can negotiate on the price.
The same thing can be done with corporations, although the allocations would be more complex - certainly doable as evidenced in the E.U. exchange.
Carbon emissions trading could be a highly lucrative market, and that my friend may be just the incentive we need.
TIME.com - What You Can Do
Global Warming - Wikipedia
Post-script - System Dynamics needs to be a required course of study for all school children, if for no other reason than it will make them better consumers of what passes for "knowledge" in our society.
Here's an example of how SD could help -
Assume you were a school kid in the 1970's who had studied system dynamics and understood something about complex system dynamics. Then assume an expert said there was no evidence that people contributed to global warning. A little bell would go off in your head and you'd think - hey no one could know that for sure. We don't have accurate models of the earth's atmosphere, ecosystem, climate, oceans...so you can't possibly know that. Then you'd say since we don't know - let's exercise caution...fools rush in where angels fear to tread as they say.
If you think about it you might be able to find some correlations between the global warming discussions in the last century where experts were sure humans had nothing to do with global warming, or that global warming was not occuring and the experts today who tell you bio engineering or genetic engineering could not possibly cause unintended advese effects. Even experts can be wrong sometimes. We have been both incredibly egotistical in our belief that we understand things we really don't, and incredibly sheep-like in the thought that the "experts" would look out for us.
One of the tenets of whole systems engineering is that we could do with fewer "experts" and more "system" engineers that can utilize knowledge from the sciences - chemistry, biology, physics, as well as ethics, psychology, sociology, history etc. to come up with solutions that are best for the interconnected system we live in.
