Scientists clearly understand the relationship between global warming and carbon dioxide emissions coming from the millions of vehicles crowding American streets and highways. Nationally, 30 percent of all greenhouse gas emissions come from tailpipes. In Maryland, the figure is slightly higher.
Unfortunately, the head of the Environmental Protection Agency doesn't share the understanding of the vast majority of scientists - even those in his own agency. He has blocked Maryland and other states from voluntarily tightening emissions standards for vehicles. It's a decision that must be reversed.
Donald Boesch of the University of Maryland Center for Environmental Studies made clear at a Senate hearing in September that Maryland also is especially vulnerable to the effects of sea-level rise, which accompanies global warming. According to Mr. Boesch, computer simulations project a rise in the Chesapeake Bay of about one meter by 2100, inundating much of our current shorelines. Given this alarming projection, some insurance companies have stopped writing new homeowner's policies in the state.
We are already feeling the effects of global warming. The Blackwater National Wildlife Refuge on the Eastern Shore has lost thousands of acres of wetlands, in part because of rising tides. Eel grass, one of the most important underwater plants in the bay, is dying as water temperatures warm. The bay's infamous "dead zones" expand as the water becomes less oxygenated because of higher water temperatures.
While the Bush administration continues to be in denial about global warming, state governments are taking bold, necessary actions.
Modeled after efforts by California, Maryland has joined 18 states in applying to the EPA for what has become known as the "California waiver." This would allow Maryland to set tighter emissions standards for vehicles than is allowed under federal regulations.
Maryland wants to reduce carbon dioxide emissions by 30 percent for all cars and trucks sold in our state by 2016. On Feb. 29, after a two-year delay, the EPA officially denied the states' request to set new emissions standards. It has since become public that EPA Administrator Stephen L. Johnson ignored the advice of the agency's scientists and legal counsel in denying this waiver. It is the first time in 50 applications for air-pollution-related waivers (covering a broad range of emissions sources) that the agency has denied such a waiver.
Denying this waiver damages the EPA's credibility. Although the courts may eventually reverse the decision, we must not rely on that possibility.
It is time for Congress to act. I have joined with Sen. Barbara Boxer of California, Sen. Barbara A. Mikulski of Maryland and others in co-sponsoring the Reducing Global Warming Pollution for Vehicles Act, which would reverse Mr. Johnson's decision and allow tighter state auto emission standards to go into effect.
If we are going to reduce dangerous greenhouse gas emissions, we need to act now. According to the National Climatic Data Center, global annual temperatures are now about one degree Fahrenheit warmer than at the start of the 20th century. The National Capital Regional Transportation Planning Board has projected that carbon dioxide emissions will increase by 50 percent between 2002 and 2030.
In denying this waiver, the EPA has shirked the responsibility embedded in its name: protecting the environment. Marylanders - and all Americans - have the right to clean air; it's time to force the EPA to live up to its duty.
U.S. Sen. Benjamin L. Cardin is a member of the Environment and Public Works Committee. His e-mail is cardin.senate.gov.