Hi Easeltine. Neither of us is an expert in the science of climate change or mitigation policies, so all we can do is read what experts in the field say. I’ve done a lot of research, downloaded some books, and am slowly getting an education.
One of my sources is Andrew Dessler, a climate scientist with a PhD from Harvard. He’s an acknowledged expert both in the science and politics of climate change. He wrote The Science and Politics of Global Climate Change: A Guide to the Debate (Cambridge University Press, copyright 2006) based on his experience as Senior Policy Analyst in the White House Office of Science and Technology; and a college textbook aimed at non-science majors called Introduction to Modern Climate Change (Cambridge University Press, copyright 2012). I bought the last one and have read most of it.
Dr. Dessler’s strategy in this book is to “just explain the science and then lay out the possible solutions and trade-offs among them,” and wrote that “I firmly believe that an unbiased assessment of the facts will bring the majority of people to see things the way I do: that climate change poses a serious risk and that we should therefore be heading off that risk by reducing our emissions of greenhouse gases.” He says that there is “wide agreement that mitigation must be part of our solution to the problem of climate change.”
Dr. Dessler mentions energy efficiency (how the economy uses energy) and the reduction of carbon intensity. This means switching from conventional combustion of fossil fuels to energy sources that do not release greenhouse gases (carbon-free sources). These include nuclear energy, carbon capture and sequestration, and energy sources known as renewable energy (hydroelectric, solar, wind, and biomass energy).
The author goes on to discuss two ways to generate energy from sunlight (solar photovoltaic and solar thermal methods), then about modern advances in wind as an energy source (wind turbines); and explains that these sources are more expensive than electricity from fossil fuels, and that the intermittency problem hasn’t yet been solved. We’re not yet on the verge of a wholesale transition of our energy supply to these renewable sources.
He goes into biomass energy as another renewable (energy through burning crops), and tells us that because the carbon dioxide was absorbed from the atmosphere during the growth of the plant, there is no net increase in carbon dioxide in the atmosphere. However, a lot of land would be needed to make the work; which would include having to clear forest areas, which would release carbon dioxide into the atmosphere in addition to a host of other local environmental impacts (loss of native biodiversity and ecosystem degradation). Not to mention the production of fertilizer that would be needed, which requires large inputs of energy.
Then there is hydroelectric energy, which currently supplies sixteen percent of the world’s energy; but it isn’t likely to increase because the world’s big rivers are already damned, and new dams often cause local environmental problems.
Nuclear energy currently generates about sixteen percent of the world’s electricity; and there is centuries worth of uranium in the ground. Reactor safety is an issue, especially after Japan’s experience following the tsunami (and Chernobyl). Then there is the fact that nuclear reactors are very attractive targets for terrorists. All in all, it’s a risky source of energy; and disposal of nuclear waste is a major problem, having to be isolated for many thousands of years.
One final option to generate energy without emitting carbon dioxide is carbon capture and storage, also known by its initials CCS or carbon sequestration. This refers to a process by which fossil fuel is burned in such a way that the carbon dioxide generated is not vented to the atmosphere. Rather, the carbon dioxide is captured and placed in long-term storage. This is not a renewable energy source, and is almost always used in combination with coal combustion.
Once captured, the carbon dioxide must be stored. The most likely place to put the carbon dioxide is to inject it deep underground into porous sedimentary rocks, which are distributed widely around the world (oil and gas fields, unminable coal beds, or deep saline formations). This process is technically feasible and would use many of the same technologies that have been developed by the oil and gas industry. The capacity of these rocks is large enough that they could conceivably hold all of the carbon emitted by human activities.
There’s a lot of coal in the world that’s likely to be burned, and CCS may be the best way to simultaneously burn this coal while avoiding climate change. Thus far, no large-scale CCS power plant has ever been built.
Then there is the question of how to encourage the world to switch away from fossil fuels to carbon-free energy sources (wind, solar, nuclear, and CCS).
Dr. Dessler follows this by addressing the question of why we need regulations to reduce greenhouse gas emissions. Do you think the free market is going to take consumers’ interests into account and reduce greenhouse gas emissions without government intervention? The answer is no.
Introduction to Modern Climate Change is an excellent source for anyone interested in the science behind “global warming,” and the technologies/policies that can mitigate greenhouse gas emissions in the future.