Critics don't understand this market or it's mechanics. Of course, new markets are opaque and fraught with cheating, corruption and growing pains. That said, carbon emissions worldwide are coming down as a direct response to the Kyoto Protocol and the Cap and Trade model for Carbon emissions. Multi-billions of dollars are currently being traded by major corporations in the compliance markets in countries who have signed the Kyoto Protocol.
Here in the US, states are mandating electricity companies to generate a % of their power through renewable sources or to purchase Renewable Energy Credits (RECs) from developers who are doing environmentally friendly projects such as solar installations, etc.
In short, the capital markets approach to addressing the Greenhouse Gas, Carbon emissions problem is the only solution to resolve Global Warming. Remember Acid Rain? Lew Ranieri developed the Cap and Trade system for SO2 and NOx and largely solved the problem. You haven't heard about acid rain much recently, have you?
Big backers are getting involved in the trade of Carbon offsets/Carbon credits in the US. Ever hear of Paul Tudor Jones, NYMEX, Evolution Markets? They have formed the NYMEX Green Exchange to trade carbon offsets. This train is leaving the station and Carbon will be next big market to trade. Maybe the biggest in the world.
Do Greenhouse Gases (GHG) cause Global Warming? Honestly, nobody really knows. What we do know is that there is little downside to reducing carbon emissions and cleaning up the environment even if Global Warming turns out to be merely a normal weather cycle. However, the downside of not acting to stem greenhouse gas emissions, now, while we have the chance to reverse and slow the process should it turn out that global warming is real and caused by man-made emissions, is simply to great a risk to accept.
Each individual must do their part to reduce, reuse and offset their own emissions. The i'm too small to matter attitude does not fly and we all bear responsibility for future generations.