Hawai'i takes pride in its environment as an element of its cultural heritage. It's central to our attraction as a visitor destination and a big part of why many of us find living here worth the high costs.

So the state Legislature deserves credit for bringing us to the threshhold of a key policy decision: Hawai'i is joining the front ranks of states committed to curbing greenhouse gas emissions.

A House-Senate conference committee will submit its final version of HB 226 for a vote on Thursday.

The measure essentially establishes that Hawai'i will place a limit on its collective production of greenhouse gas emissions, a key component in the acceleration of global warming, and will meet that limit by 2020.

This bill should become law.

Lawmakers have patterned the bill after legislation pioneered by California, which last year adopted the goal of reducing emissions to 1990 levels — the ceiling set by the international Kyoto Protocols in 1997.

It appears that it will take the prodding of states to push our leaders toward such a commitment. The U.S. opted out of signing the protocols.

And more recently, we saw another demonstration of that head-in-the-sand posturing: At this week's Intergovernmental Panel on Climate Change meeting in Thailand, the U.S. and China delegates cast doubt on researchers' claims that immediate actions to stabilize emissions could affect global warming.

So it looks as if the federal government, barely willing to acknowledge the problem, won't be part of the solution until it's forced to do so through the leadership of the states.

The approach proposed in HB 226 is a measured one that's feasible. A task force will recommend specific ways Hawai'i can reduce emissions, in a plan due by the end of 2009. The Health Department then will establish limits to be attained by sources of emissions — including the biggest source, electricity production, and automobile emissions. Rules and penalties will take effect in 2012, giving the state eight years to attain the reduction goals — about 15 percent less than current levels.

Toward that deadline, the state must encourage incentives for energy conservation and alternative energy sources to reduce our reliance on fossil fuels. Hawai'i must be in the forefront of this campaign.