An article in the Washington Post discusses the various uncertainties surrounding the Waxman-Markey climate bill, from what it will look like in its final form to how some provisions will work in practice. The plan has already been substantially compromised as a result of its narrow passage through the House Energy and Commerce Committee. There will be further modification, for better or worse, as the bill passes through the House and (hopefully) the Senate.
The big question is how effective the bill's cap-and-trade system will be.
The United States already has a working cap-and-trade system, used since 1995 to cut back the gases blamed for acid rain. The Environmental Protection Agency says the trading system has reduced the overall cost of cutting acid-rain-causing pollutants to one-third of what was projected.While a declining cap ought to force reductions, how effective a cap-and-trade system will be depends on who has to abide by its limits and how much allowances cost. The system is already being set up for ineffectiveness by giving away most of the permits for free and creating a dubious offset program. Many industries are lobbying heavily for exemptions from emissions rules, and many will no doubt succeed. Others are trying to get dirty or toxic fuel sources classified as "clean energy."
But comparing the two problems is like comparing a horn section and an orchestra.
Acid-rain pollutants can be sucked out of a smokestack by adding "scrubbers." But nothing like that is commercially available for carbon dioxide -- polluters might have to replace the coal they burn with a different fuel, or replace the coal-burning plants with solar "farms" and windmills.
Also, greenhouse gases come from far more sources: power plants, factories, car tailpipes, and both ends of a well-fed dairy cow (though the bill doesn't tackle that one: cows could still burp free of charge).
In this environment, it is hard to see a strong bill getting passed. Whatever emerges from the legislative meatgrinder is likely to have serious flaws and may not meet the timetable for avoiding catastrophic climate change suggested by scientific research. Some reduction is better than no reduction, but some reduction may not be enough.