My personal concern is not whether or not global warming is actually happening or not, nor whether or not we are affecting it.
My concern is this: what if it IS happening, and what if humankind's actions are the main (or even strongly contributing) reason behind it?
I see much less risk from trying to minimize the effects on climate compared to wishing for the best by believing that nothing is wrong and that even if global climate change is going on we couldn't do anything about it.
The risks of tryign to minimize the climate change are economical expenses from trying, and possibly failing at it. Benefits would be continued status quo, or possibly taking the sharpest edge off from an inevitable change, giving us more time to adapt to the changed climate. After all, barring Venusian style climate change, the change itself is not the problem but it's rate is.
On the other hand, we keep going on as we are, and it turns out the climate does change, rapidly, and for the worse, and we have a cluster**** of unseen proportions falling over the humanity, resulting in a lot of human suffering, economic breakdown, loss of infrastructure and lives. This is the worst case scenario and in my opinion, the risks of this far outweigh the risks of actually trying to affect thigns a bit.
People equipped with rational thought know this, and combined with the fact that an economy that requires perpetual growth cannot work forever with limited resources, it would be better for long term to just put limiters of some sort in place for stuff like rate of consuming fossile fuels, no matter whether the climate is changing or not.
Of course, there's a logical conundrum there; by this logic, anyone could postulate all kinds of horrible things and say that it is better to prepare for them than not to prepare for them, but then such is the case of all risk analysis. Building a meteor shield for your home is by all statistical analysis a loss of resources in all practical sense. Building a Geofront against the invasion of powerful alien species would be folly considering we don't even know of any viable way for interstellar travel. The thing is, though, that the hypothesis of global climate change to warmer environment has some rather compelling evidence to make it plausible.
First and most important is that Earth is currently in an ice age. There are polar ice caps, and this is very unusual in geological timeframes. Most of the time Earth has existed, there have been no ice caps and climate has been a lot warmer than in the pleistocene era. On the other hand, it's equally possible that we are in a period between more powerful glaciations and that there would be another ice age behind the corner. This possibility should never be denied when talking about climate changes. Also, it is good to keep in mind that the climate is essentially a very chaotic system with too many variables for anyone to predict things with absolute certainty. At best, our long term projections are more of educated guesses than absolute authorities. The only things we know for sure is the average energy received from the Sun, and that is bound to only increase as time goes on, but that's in really long term; in the space of tens of thousands of years, the activity of the Sun remains largely unpredictable beyond the 11-year cycle of sun spots.
Nevertheless - in the long term, the prediction is that there will be no ice caps. For most of the time. Antarctic ice will melt at some point and the water bound there will be released into the water cycle, partially into atmopspheric water vapour and partially into oceans. The question is, what happens before it, whether human activity affects it, and how fast will the changes happen.
Another thing to consider is that a lot of the carbon that was in the carbon cycle in the prehistoric warm eras - I'm talking about triassic, jurassic and cretacean here - is currently bound in fossil fuel reserves which we are rapidly cycling through. Both the carbon dioxide and oxygen levels were higher if I recall correctly, which made very large insects and very flush vegetation possible. Now I don't personally really think that there's much risk of Earth turning into another Venus, but obviously some connection might be here. During the ages of dinosaurs, a lot of carbon was in the carbon cycle, and it was warm. A lot of the carbon was bound into fossil fuel as remnants of the plants fossilized and were covered in sediment layers, and then climate got a lot cooler.
Of course, correlation does not imply causation; there could be a thousand other reasons why the climate got cooler; redistribution of continents changing ocean currents and dominant winds is a good one, but the fact is we ARE pumping a lot of carbon dioxide into the atmosphere while also affecting the amount of vegetation that cycles the carbon around in the biosphere. All these things combined, and the possibility of human activity affecting climate is not exactly that far-fetched to me.
The thing is, though, that we only really have hard data from a very short time period and all who know any statistics should be aware that making projections from such a short range of measurements is unreliable at best and guessing at worst. The thing is, though, that there are other negative effects caused by the same things that allegedly drive the climate warming, and I can easily see why some people would want to politicize these things by banding them under the umbrella threat of climate warming and add some scientific credibility to the opposition. It's unscientific and ultimately harmful for any sort of cause for more sustainable, economic way of doing things, but I can see where these people would be coming from.
In other words, it's easier to get people to maybe care a little bit if you say their actions threaten the way of their life, rather than just say that cutting down the mightiest trees in the woods with an overfished herring population while burning a lot of coal and oil might be unwise in and on itself.
Of course, while some people say one thing, others say that the spice must flow, and economy must grow to appease the beast, and that everything will be good and well as long as profit is made (after all you're only in this world for seventy odd years or so, what's going to change during that time).
Fear, uncertainty and doubt are powerful propaganda tools for any cause, and I can see why using them is so tempting.
