I'll limit my reply so we stop clogging in-boxes with debate.
Paul argues that the situation is already dire, that draconian measures are need immediately, and that biomass fuels and carbon sequestration are "dead-end strategies" that deflect needed resources.
My position is that, although dangerous climate changes may occur within another generation or two if we maintain a business as usual scenario, a less draconian transition, if begun today, will provide important breathing room to allow new technologies to develop and to transition society to a more sustainable pathway without udergoing a collapse of civilization. Biomass energy should be an important component of the transition and is sustainable over the long term.
Paul argues that dangerious climate changes are already occurring with temperature increases of 1 C, or that we will be irreversibly committed to this within 5 years. Most of the climate models suggest that changes of 2 C will produce significant adverse impacts to the environment, although even this would not cause human extinction without invoking some as yet unknown mechanism. The current level of CO2 is approximately 380 ppm, compared to a pre-industrial level of 280 ppm. Levels of 450 to 550 ppm would produce the 2 C temperature change likely to cause adverse impacts. These levels would occur by the end of the century if current trends continue.
Use of energy is a fundamental characteristic of human life, and modern society uses much more of it than a subsistence-level civilization. The question is whether a 1 C change will cause dramatic threats to humanity, in which case Paul is correct, or whether we can tolerate some warming and 2 C is the threshold, in which case we have time for a more gradual transition.
JBK
P.S. The Sierra Club's energy policy is calling for a 2 % per year reduction in CO2, with the goal of achieving approximately 50-70 % reduction by 2050.
>>> "Paul Brown" <pbbrown(a)hsc.wvu.edu> 09/28/06 1:04 PM >>>
Jim,
I love it when you talk technical. Seriously, your feedback is very useful, and my article will benefit from it.
In the original order of presentation, I basically followed a chronological sequence of the development of thinking about the use of biofuels. The earlier sections are less important than the conclusion. I assume you all got the article about Hansen's contention that one degree more warming will cook our gooses. Many other scientists are beginning to agree, at least with the concept, if not with the actual tipping point.
Based on the past 30 years, a one-degree change will take 50 years, but warming is accelerating steeply, not only because of the positive feedback effects of decreased albedo and methane release, but also because carbon combustion is skyrocketing as developing countries increase their consumption (even the developed ones are burning more carbon). Estimates indicate that China alone will need 100% of current oil production by mid-century, and India is projected to have more people than China by then. I believe it's prudent to assume we have only 20 years before we hit the 1-degree mark, in the worst case. Being unprepared for the worst case is imprudent because we can't afford to get this wrong. There’s no second try allowed. The only tools we have are reduced atmospheric CO2 and increased albedo. The longer we wait to take realistic measures, the less likely we are to survive.
If we were to stop burning carbon today, the warming trend would not stop, but it would slow. We would still reach a 1-degree increase, perhaps as late as the end of the century, because of the long persistence of CO2 and continued positive feedback effects of ice melting and methan release. We would still need to remove a lot of existing CO2 from the atmosphere faster than nature can do it for us. It's much easier to stop emitting CO2 than to remove it from the atmosphere, and we can't possibly sequester all the CO2 we produce. Therefore part of the solution must be to stop burning carbon. The planet doesn't care, by the way, if this is economically or politically impossible.
We can't stop burning carbon today. What's the absolute fastest we could do so, if we mobilize as a nation, and then assist the rest of the world to do the same? My guess is five years for the US, 10 years for the rest of the world. It may take longer, but we should shoot for these times because we don't know when is too late. The mobilization of resources and effort will have to be greater than it was for World War 2. It would require returning to a non-consumer society, with gratuitous (non-vital) consumption dropping to pre-electricity levels, and vital consumption (e.g., health care, development of new infrastructure) maintained as well as possible.
This has to be our first priority, because there is simply no choice if we are to survive. If we do less, we die, probably by the end of the century. (Note: these time frames are all my guesses, based on the 1-degree limit and the positive feedbacks already in operation). While economic considerations are important in choosing solutions, and I don't claim to know the detailed economics, the solutions have to include switching from carbon to non-carbon energy as fast as possible, with all the lifestyle changes that may be required.
As for the inefficiency of energy production from biomass and the unavailability of farmland to grow it, I stick to my stance: we need to use all available land for fast-growing (rapidly photosynthesizing) forests and relocation of endangered ecosystems. But the ciritical point is this: biomass and biodiesel are largely carbon. To stop global warming, every atom of biofuel carbon we burn from now on will have to be removed from the atmosphere (except for sequestered CO2, and we can't sequester CO2 from vehicles or heating buildings), which would require burning many more carbon atoms, in an absurd endless regress. Or look at it this way: By growing trees instead of biofuel crops, we not only don’t emit the biofuel CO2, but we absorb vastly greater amounts of CO2 already in the air. In fact, we’d be better off planting the trees and burning an equivalent amount of fossil fuels, because we’d have a net loss of CO2 instead of just breaking even.
As for the economic advantages and disadvantages of solar and wind, we have no choice but to use them. The exact mix is not the issue here. Don't be distracted by that. We have to use whatever non-carbon energy sources we can get up and running fastest, given economic and environmental constraints. During the transition, we have to eliminate non-essential carbon combustion by rationing carbon, eliminating non-essential travel. The best way to handle vehicles is to convert them for hydrogen internal combustion, on a prioritized basis. Most airplanes would be grounded for good. So would our private vehicles, until essential vehicles (e.g., public transportation) have been converted. No more soccer moms because no more SUV soccer trips. We would switch from trucking to railroads and ships, and local production of essentials like food, clothing, and shelter from locally available materials. We wouldn’t be smelting metals, we’d be recycling them.
Jim is right about the implications of abandoning carbon combustion. They are not pleasant. The alternative is far worse, however. Given the urgency of this crisis, we have to stop thinking in terms of business as usual. There will be enormous economic losses, although there will also be some enormous savings. Other concerns, including dependence on foreign oil, terrorism, illegal immigrants, and international economic competition, become supreficial.
With regard to credibility, the programs espoused by the Sierra Club, such as biomass energy, are not credible at all to an informed public. They reflect an understandable denial which we unfortunately can't afford. Their only benefit is they may get people moving in the right direction, but we have very little time to make them move far enough * way beyond schemes like Cool Cities. We also can’t afford to deflect any resources to dead-end strategies like biofuels.
Paul
Paul Brown
Physiology Department
West Virginia University Health Sciences Center
Morgantown, WV 26506
(304) 293 - 1512