BY BILL GEROUX

Times-Dispatch Staff Writer

WILLIAMSBURG -- In the computer-generated image, the rising sea swirled among downtown Norfolk's high-rises and clawed at the edges of historic Fort Monroe.

The blue water engulfed several blocks along Norfolk's downtown waterfront, transforming buildings into islands.

The images, provided by defense contractor Lockheed Martin's modeling and simulation center in Suffolk, depicted Hampton Roads a century from now, when scientists say sea level is expected to rise by at least 2 feet.

With a mouse-click, Lockheed Martin analyst Chris Mang showed the impact of a routine winter nor'easter striking on top of the higher water level. Large parts of the city went underwater, much as they did during Hurricane Isabel in 2003.

"In a hundred years, even your average storm becomes a real problem," Mang said. And a hurricane with Isabel's punch would cause far more damage than Isabel did.

Mang was among the speakers today at the College of William and Mary as the 43-member Governor's Commission on Climate Change held its third of eight scheduled meetings. Gov. Timothy M. Kaine formed the commission to study how global warming could threaten Virginia and to suggest ways to combat it.

Two other speakers, marine scientists, warned that rising sea level and water temperatures would cause a wide range of problems for humans and animals in Virginia, whose coastal region includes almost 2 million people and $130 billion worth of property.

But representatives of the automobile, manufacturing and power industries warned the panel to move cautiously in proposing state limits on the emissions of carbon dioxide. They said the wrong move could harm the state's economy while accomplishing little.

Carbon dioxide and other greenhouse gases hold heat close to the planet and keep it habitable, but scientists say a continuing buildup of those gases from human activity is overheating the Earth. The sea level is rising because glaciers melt and because water expands when it gets warmer.

Virginia is one of 29 states considering its own climate-change initiatives out of impatience with the federal government's inaction on the issue. An energy plan by Kaine's administration calls for reducing Virginia's greenhouse gas emissions 30 percent by 2025.

Determining how to do that is one of the jobs of the commission, whose members range from environmentalists to high-ranking industry officials. The commission is to release its recommendations by December.

Yesterday, professor James E. Bauer of the Virginia Institute of Marine Science in Gloucester Point told the commission that a rising sea level will change the dynamics of the Chesapeake Bay and its tributaries, making them saltier and interfering with water circulation.

Another VIMS scientist, J. Emmett Duffy, said higher water temperatures will disrupt the life cycles and migration patterns of numerous aquatic creatures and may wipe out the bay region's precious aquatic grasses, which provide food and shelter for juvenile fish and crabs.

Duffy said higher water temperatures could eliminate winter flounder from the bay region and cause declines in rockfish, sturgeon and crabs.

Michael J. Stanton, a lobbyist for the automobile manufacturers, told the commission that automakers are working on new vehicles to be powered by batteries or fuel cells rather than fossil fuels. One experimental car could travel for 40 miles on the power it banked from being plugged in overnight, he said.

Commission member Harrison Rue asked why some automakers are still trying to glamorize big, fast, gas-guzzling vehicles. Stanton blamed the marketplace. "Some people actually get their image from what they drive," he said.

Keith McCoy, a spokesman for the National Association of Manufacturers, said a patchwork of carbon dioxide emission limits by states would create confusion and possibly prompt industries to move to less restrictive states, with no net loss in emissions.

McCoy said polls suggest that while people want to reduce greenhouse gases, "they don't want to give up their SUVs, and they don't want to turn down their thermostats."

One commission member called McCoy "plain wrong."

Contact Bill Geroux at bgeroux@timesdispatch.com.