are we moving towards global warming
December 28, 2006 6:35am CST
28 Dec 06
It may not be necessary to make large efforts to avoid global warming. First of all, it may not happen, and, secondly, it may not be harmful if it does. The warming observed to date, which may or may not be partly due to human activity, seems to have been beneficial in lengthening growing seasons in temperate and northern climates. Since serious efforts to reduce CO2 emissions or to increase CO2 sinks are likely to be extremely expensive, for the present it is best to wait. . However here are some things which can be done Replace coal, oil and natural gas plants for generating electricity by nuclear plants. Replacing coal burning plants should get the highest priority, because they generate the most CO2 per unit of energy generated, and because their emissions cause substantial lung damage. (It is interesting that some the proposers of "carbon taxes", both in America and Europe, want to include nuclear energy as a target of the "carbon tax". There is clearly more on the agenda than global warming.) Solar energy in various forms would also work, but it seems to be very costly in spite of the best efforts of its advocates. Unfortunately, generating electricity without putting CO2 into the atmosphere probably wouldn't be enough if the global warming problem is serious. The next step is to use nuclear produced electricity for space heating and other direct uses of heat. The most difficult step is to use electricity for automotive transportation. In spite of very vigorous research, batteries capable of giving electric cars reasonable range have not been developed, although there seems to be no law of nature making them impossible. Here's a scheme that would ameliorate the problem even if lead-acid batteries had to be used. Another approach is to use hydrogen generated by splitting water with (say) nuclear electricity. Cars powered by liquid hydrogen have the potential of matching the performance of gasoline powered vehicles. The hydrogen tanks will need three times the internal volume of gasoline tanks and still greater external size because of the insulation required. BMW has demonstrated a liquid hydrogen powered internal combustion engine car. Schemes for using hydrogen in other forms than liquid are unlikely to have the required range. See the page on hydrogen for more details. Some people seem to believe that using hydrogen gets more energy. It only provides a way of using nuclear or solar energy. Apart from its possible use to reduce global warming, hydrogen it likely to be the solution for personal transportation when petroleum runs short. Rather than putting all the effort into reducing carbon emissions, it may be more cost-effective to put some effort into removing more CO2 from the atmosphere. Plants remove CO2, but only while they are growing. A climax forest may be in equilibrium; apparently the exact facts are not yet known. What will surely work is to cut down forests, not burn the wood and replant the forests with fast growing trees. When these trees reach a size at which their growth slows, they would be cut again. Back in the carboniferous era, trees fell into swamps which evidently provided a reducing environment. The oxygen and hydrogen in the wood were re-emitted into the atmosphere, and the carbon became coal. This process will work for us too (to reduce CO2 (it takes too long to make coal) if it proves necessary. Canada and Siberia have large forest areas not being used for other purposes.