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It's the Carbon, Stupid!

In my previous blog posts, I hinted at the potential hopelessness of trying to roll back global warming. While it is true that economic growth, with existing energy policies, leaves us in a serious predicament, alternative policies can significantly slow the trend in global warming. Consider this Scientific American article on carbon capture and storage:

But carbon capture and storage will play a key role as coal continues to supply a significant portion of world energy supply and, unfortunately, it has yet to be demonstrated on any power plant anywhere. The U.S. Department of Energy (DOE) has at least 20 pilot projects to investigate it, according to Stephen Eule, DOE's director of the climate change technology program, but none have applied it on a commercial scale. A variety of techniques, including passing the remnants of coal combustion through an ammonium carbonate solution or separating purified CO2 from gasified coal, are possible -- at a cost. "There is no plant that integrates gasification with capture and sequestration," says physicist Ernest Moniz of the Massachusetts Institute of Technology, who co-chaired a report on the future of coal. But "gasification looks today to be the lowest cost option with carbon capture."

What this means is that our energy plants could produce the energy they are producing today but with substantially fewer CO2 emissions than before. Like nuclear waste, the captured CO2 needs to be contained and stored someplace. One potential answer is to pump it into the cavities from which we extract oil and natural gas. There's more good news:

There are other technologies available, such as using algae to capture the waste greenhouse gases from power plants and turning it into diesel or other fuels. "The amount of CO2 that you capture [with algae] is very high and the amount of biofuel created per acre is incredibly greater than you can do with corn or even sugarcane," Tufts's Moomaw says. "The problem is it only works in the daytime." Alternative forms of power production, such as wind or solar, remain a small -- albeit fast-growingÑportion of world electricity supply. Even nuclear power is unlikely to play a major role in fighting climate change. "By 2030, we might be seeing something around 18 percent of power being generated by nuclear rather than the 16 percent we see today," Moomaw adds. "There are so many issues around nuclear power, we don't see it as being the answer to global warming and the electricity sector."

So, use the CO2 to feed algae, which in turn create biofuel through photosynthesis, which in turn can be used in increasing amounts to fuel vehicles. This is basically the equivalent of "Reduce, Reuse, Recycle" applied to CO2 generation.

But, as I've said before, it's not sufficient just to cut back on the rate of CO2 emissions, we need to reduce net CO2 emissions on a global scale to a level we were only producing decades ago. The good news is that there are two ways to actively absorb atmospheric CO2 (not just to reduce our emissions of it) that you and I can actively engage in.

The first is reforestation. Each tree planted is estimated to consume one ton of CO2 in its lifetime putting O2 back into the atmosphere. Plant a tree in your back yard, or donate to someone who will: Plant a Tree Today American Forests.

The second is to shift your consumption towards organic products. Traditional farming practices have a net CO2 generation effect, but organic farming (i.e. no-till, residue mulching, cover cropping, grass-fed free-range meat, and crop rotation) have a neutral effect on atmospheric CO2.

Another method to reduce atmospheric CO2 is to encourage oceans to act as more effective CO2 sinks (such as the Southern Ocean which in recent news was shown to be losing its ability to absorb carbon dioxide). When oceans can't absorb CO2, it discourages plankton growth and starts to undermine the ecosystem of the ocean. Doing so means adding iron oxide or iron sulfate to the water to stimulate plankton growth, but this is a drastic measure that we hopefully won't have to resort to.

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