As Sea Level Rises, Disaster Predicted for Va. Wetlands
Thursday, June 7, 2007
More than half of the wetlands along Virginia's coastlines could be drowned by rising sea levels in the next century, destroying wildlife habitats and natural filters for the Chesapeake Bay, according to an estimate released yesterday by an environmental group.
The Norfolk-based group Wetlands Watch examined maps of low-lying marsh areas along the bay and the Atlantic Ocean and compared them with projections that water levels may rise 1 1/2 feet or more in this area by 2107, Executive Director Skip Stiles said.
Stiles said the group determined that at least half, and perhaps as much as 80 percent, of the wetlands would be covered in too much water to survive if sea levels rise 1 1/2 to two feet. He said that could be a crucial blow to a number of species, from fish to blue crabs to birds, that live in the marshes for some part of their lives. It would also harm the bay, which relies on wetlands to filter some pollutants, he said.
"You can lose a little bit here and there," Stiles said. "But when you start losing it throughout the bay, and then on the East Coast, then you've got a serious problem."
Stiles said that his group's methods were relatively crude; members wanted to use more detailed elevation maps, made by using aerial photography or laser imaging, but none were available. His group wrote a letter to Virginia Gov. Timothy M. Kaine (D), asking that the state create more such high-resolution coastal maps.
"What we're saying -- to the governor and to others -- is: 'Do the analysis. Please prove us wrong' " and show that sea-level rise would not cause so much damage, he said.
A spokesman for Kaine said yesterday that Virginia was trying to work with other states in the region to better understand the effects of rising waters. "We all recognize that it's an important issue," Kevin Hall said.
Rising sea levels are expected to be a global problem in the next century, in part because of emissions of greenhouse gases that trap the sun's heat. As the Earth warms, researchers say, warm water will expand in volume and polar ice caps will melt. Both are expected to raise the level of the world's oceans.
In some places across the Chesapeake region, the effects are being seen. In the marshes of Virginia's Pamunkey River, east of Richmond, researchers have watched plant populations shift over the past 30 years. As water levels have inched upward, Virginia Institute of Marine Science Prof. Carl Hershner said yesterday, the plants that remain are the ones that are more tolerant of flooding.
"I would guess that they're in the right ballpark," Hershner said of the Wetlands Watch estimate. "Certainly, a vast majority of the wetlands are at risk of not being around."