Dear EarthTalk: What's the latest in regard to putting limits on greenhouse gas emissions in the U.S.? Is there any hope that Obama can get something done?--Bradley Johnson, Helena, MT
Our best hope to date was 2009's American Clean Energy and Security Act (ACES), a bill that called for the implementation of a "cap-and-trade" system to limit carbon dioxide emissions by capping overall emissions and allowing polluters to buy or sell greenhouse gas pollution credits--similar to what the European Union has been doing since 2005 to successfully reduce its own emissions--depending upon whether they were exceeding established limits or had succeeded in coming in below them.
According to the bill, U.S. businesses needing to pollute more could buy emissions credits on the open market; those able to reduce emissions could sell their pollution credits on the same trading floor. Thus there is a built-in incentive to reduce emissions: If you exceed pollution limits you have to keep buying costly credits; and if you can get below limits you can profit from the sale of credits for the difference.
Among the bill's key provisions was a 17 percent reduction in greenhouse gas emissions below 2005 levels by 2020, with a mid-century goal of an 80 percent reduction. Also, billions of dollars would have gone to initiatives bolstering green transportation, energy efficiency and related research and development. The bill was approved by the House in June 2009 by a narrow 219-212 vote. But Senate Democrats decided they didn't have enough votes to get a version of the bill passed, and tabled the discussion.
While ACES may not have made it into the law books, its passage by the House was significant as it represented the first time the legislative branch called for sweeping climate legislation. Also, the bill's provisions served as a guideline for U.S. negotiators heading to Denmark later in...