As leaders, members of Congress may wonder why their view of global warming consists mostly of the backs of companies, states and other nations well ahead of them in the kinds of sensible changes in energy policies that climate change demands. The next example Washington will see comes from the Northeast, including Maine, where a system that is proving popular elsewhere is expected to be unveiled here next month.

The Regional Greenhouse Gas Initiative, which also includes New Hampshire, Vermont, Rhode Island, Massachusetts, Connecticut, New York, New Jersey and Delaware, is preparing to release a cap-and-trade system for greenhouse gases that rewards efficient use of fossil fuels and provides incentives for innovation. A cap-and-trade system works by governments setting a cap, or limit, below the current emission level from a specific source – say, power plants. The emissions amount is divided into credits, which companies can trade, buying or selling based on their levels of efficiency and demand.

The Northeast’s greenhouse-gas reduction plan complements California’s, where Gov. Arnold Schwarzenegger issued an executive order that would cut these emissions by 80 percent below 1990 levels by 2050. Other states also have proposals and companies such as General Electric, Duke Energy, Cinergy and Exelon aren’t waiting for a dawdling Congress and have taken steps to restrict carbon dioxide emissions.

But the most encouraging advances come from Europe, which began trading carbon-dioxide permits in January and found a market for carbon-dioxide credits much hotter than anticipated. The market covers factories and power plants, which have been more active because, according to news stories, high gasoline prices there have pushed the plants into relying more heavily on coal – and having to pay the price for the added pollution. That, naturally, affects consumers but it also supplies motivation for newer technologies that use cleaner fuel.

As scientists learn more about the contribution by humans to the planet’s rising temperature, they are increasingly able to point to the health and safety risks the changes present as well as the economic consequences of climate change. Ignoring this global issue, as the latest energy bill passed by Congress does, is thoroughly irresponsible. Actively opposing mandatory limits on emissions that worsen the problem, as the Bush administration does, is unacceptable.

Even some conservative members of Congress seem to have realized this. National Journal recently reported that Sen. Pete Domenici of New Mexico, chairman of the Senate Energy and Natural Resources Committee and the person most responsible for getting the energy bill passed, now accepts the dangers of climate change and is working to develop a proposal to combat it.

It’s too late for Congress to lead on this issue, but it isn’t too late for it to act. As states such as Maine and its neighbors curb greenhouse gases Congress should figure out how these systems could be applied nationwide and support their passage.