With just a few exceptions, scientists agree that global warming is real and one of the thorniest problems our world will face in the near future. Despite the years of awareness and study after study proving a rise in the Earth’s temperature, in 2010, “global emissions increased by the largest amounts on record.” What can be done to reduce human-based causes of global warming? Technologically? Politically? Economically?
The Earth is a finite resource. Even if you subscribe to the abiotic theory of oil in the ground, the Earth's population is ever-increasing, and will eventually be too large to sustain any supposed new oil production. The obvious solution is alternative energy, but from everything I've read, solar and wind power is simply not at the efficiency standard yet to replace fossil fuels. The less obvious solution is to draw on the much-maligned nuclear power plant, but develop them with the element Thorium instead of uranium or plutonium. Thorium fission reactors are far safer and cannot melt down; the existing nuclear waste from old nuclear reactors can be used up in kickstarting the thorium reactors -- no more waste dumps! This is the future of energy production; Norway is experimenting with long-term thorium reactors already. Thorium will eliminate dependence on foreign oil and lessen environmental impact, and the human impact on global temperatures will lower.
As litteacher says, planting trees is a great idea, especially in parking lots and around shopping centers and super markets. In general though, this is a difficult issue. There is a point at which a momentum overtakes an effect and the results amplify and cascade into greater and unforeseen events. For example, when projecting the rate of "calving" (breaking off) of ice shelves in the Antarctic, scientists considered sun, wind and rain; I'll call them top-down effects (though I'm sure glacial scientists do not call them that!). They were therefore unhappily surprised that the calving rate was far greater than anticipated. They had not foreseen that melting surface ice would run down crevices and deepen them and ultimately add a bottom-up melting effect by forming pools of running water beneath the ice shelf increasing the rate of breaking off by an alarming degree.
My point is that we don't know whether wea re at the point or approaching it or past it. It seems wise to assume the worst and think we are past it. Thus anything we do, has to be done expediently. It seems one of the most impactful things that might be done in America is (1) to speed up the release of non-polluting automobiles or (2) to increase incentives to convert automobiles to non-polluting alternative fuels (I'm thinking at the moment of those who have converted to cooking oil fuel). Another impactful step is to regulate much more stringently what is disposed of in our oceans and how it is disposed. Our oceans are critical to our planetary health and they are degrading rapidly with increasingly large Dead Zones and increasing newly appearing Dead Zones.
There is obviously a need to continue to research and develop non-fossil fuel energy sources, in addition to new fossil fuel energy sources (shale, etc.). With that said, I don't think anything dramatic is going to happen in the non-fossil fuel area until we really see the end of the supply staring us in the face. We are still complacent and we still don't really believe that there will come a day when there is no gas left to put in our vehicles.
I think that the major things that can and should be done center around education. With education will come the desire to be more "green." When kids learn about the possible impacts of climate change, they tend to want to do things like using less energy. As they come to want this, they will also demand more in the way of green technology. If the demand for green technology comes from the grass roots (rather than being imposed from above) it will be much more politically palatable to more people and will be more likely to succeed.