With so much attention devoted to the need to reduce carbon dioxide emissions, scant attention has been paid to another greenhouse gas that is contributing to global warming – methane. That would change under an international initiative that aims to capture methane emissions from coal mines, gas fields and landfills in developing countries. While this is a worthwhile initiative, it does not take away from the need to regulate and reduce emissions of carbon dioxide, by far the top gas linked to climate change.

Although methane is less abundant than carbon dioxide, it is more than 20 times more effective at trapping heat. However, methane accounts for only about 10 percent of greenhouse emissions worldwide while carbon dioxide accounts for more than 80 percent, based on both gases’ heat trapping capacities. Further, the largest single contributor to global methane emissions is agriculture, not coal mines and landfills.

So, while lowering methane emissions is a good idea, doing the same with carbon dioxide is critical. Yet, the administration, which is now touting the methane plan, has yet to regulate carbon dioxide as a pollutant. Many other countries have pledged to lower their carbon dioxide emissions – and many are already doing so. The United States, which is responsible for a quarter of global carbon dioxide emissions, has refused.

In the absence of federal action, many states, including Maine, are working to cut emissions locally. In 2001, the New England Governors and Eastern Canadian Premiers pledged to reduce greenhouse gas emissions to 1990 levels by 2010 and to 10 percent below 1990 levels by 2020. Maine was the first state to enact these goals into statute. Already state government has reduced its greenhouse gas emissions by 4 percent by reducing energy consumption and increasing its use of renewable energy, including biodiesel to heat building and fuel vehicles.

Again, it is nice that states like Maine are taking action, but without federal regulations, the biggest sources of the gas – vehicles and factories – will remain largely unaffected.

More positively, the United States has reduced its methane emissions by 5 percent since 1990. This has been done by capturing methane from coal mines and landfills and turning it into electricity. Aside from emissions reductions, this process also has the benefit of producing energy from “waste” gas rather than burning additional natural gas or coal or oil, all of which emit carbon dioxide and other greenhouse gases.

Now the Environmental Protection Agency is proposing to spend $53 million to help companies that have developed methane capture technologies export them to developing countries. The theory is that enabling developing countries to quickly put such technologies to use will help improve the environment and save money. It will also make a lot of money for companies in the seven countries that have engineered the deal.

The cost-benefit study on the project three or four years from now should make for interesting reading.