Think globally, act locally, as the saying goes. All over the country, one thing is becoming clear: Local governments — cities and counties — are emerging as the leaders in the struggle to reduce our carbon footprint and fight global climate change.

King County has helped lead the creation of a national coalition of cities and counties called Climate Communities, aimed at fighting global warming at the local level and seeking a strong federal partnership to support such local actions.

But King County and Climate Communities need national legislation to ensure that global warming issues can be effectively addressed by leaders at all levels —especially local.

Local governments are asking the Senate to quickly pass S. 2191, the Lieberman-Warner Climate Security Act. This landmark legislation calls for a 65 percent reduction in U.S. carbon emissions by 2050. The bill creates a carbon “cap-and-trade” system to set limits on the pollution that is causing our climate to warm, and to allow early reducers to trade credits to others still struggling to reduce their own carbon footprint.

Climate Communities is working with key Senate leaders to make sure that this legislation provides incentives and resources to help more cities and counties become early adopters of global warming solutions.

As a national leader in the fight against climate change, King County can share expertise with other Climate Communities members.

Our own King County Metro Transit is purchasing 500 new hybrid buses. We worked with manufacturers to develop these vehicles, and our large order is creating the kind of market needed to expand the availability of hybrid buses to other buyers.

Other counties have done similar work. Nassau County, N.Y., has launched an energy savings program for homeowners. Sacramento County, Calif., has established an ambitious blueprint to guide sustainable growth and development that will reduce vehicle use.

In 2006, King County joined the Chicago Climate Exchange, a program that reduces greenhouse gas emissions in North America through binding goals and the trading of “carbon credits” granted for a variety of activities such as reforestation efforts, forest protection, and management of landfill emissions. Last year, King County joined several other large urban counties nationwide for the Cool Counties Climate Stabilization Initiative, an effort aimed at achieving an 80 percent reduction in carbon emissions by 2050.

King County also has taken action to increase transit service through passage of Transit Now and formation of the King County Ferry District. We’ve passed a green fleet initiative and are currently reviewing green building legislation. At our landfill and wastewater treatment plants, we are implementing waste-to-energy technology.

These local efforts are examples of the impact that community-based programs can have. The next step is for local governments to band together in programs such as Climate Communities to advocate for using these local programs on a national level.

Buildings, for example, are responsible for a third of U.S. greenhouse gas emissions. Local governments can adopt green building codes and incentives that produce more efficient structures, thus helping reduce one of the top causes of global warming. Localities can use and promote renewable energy options such as solar and wind power.

Transportation is responsible for another third of climate changing gases in the U.S. — and more than 50 percent of our greenhouse gas emissions in the Central Puget Sound region. City and county governments can modernize their vehicle fleets by switching to fuel-efficient and hybrid cars, trucks, and buses. We can establish new public transit options or improve our existing service, and make it easier to walk and bike.

Local governments will be the “first responders” as impacts of global warming are felt. When drought caused by global warming shrinks drinking water reservoirs and threatens communities with wildfires, it is local government that forms the front line to prevent harm to citizens. Supercharged storms ravaging a coastline, rising sea levels turning aquifers brackish, or record heat waves causing health emergencies are all crises that local government will have to address.

Climate change may well be the greatest challenge to face not just this generation, but any. Our national campaign to meet this challenge should include effective local-federal partnerships as a key component, because local governments are where the action is.

Now is the time.

Dow Constantine, Larry Phillips, and Jane Hague are members of the Metropolitan King County Council.