UM oceanographer tracks rising water levels in Chesapeake Bay -- Gazette.Net


This story was corrected on Aug. 9. An explanation follows the story.

Ming Li is talking to the state Department of Natural Resources. He’s been meeting with the Maryland Emergency Management Agency and the Federal Emergency Management Agency.

Li, an oceanographer, has spent the past two years studying the Chesapeake Bay, and while his findings have been published in national and international journals, they are little known outside the scientific community. He’s doing his best to change that.

“People aren’t aware of the research,” said Li, a professor at the University of Maryland Center for Environmental Science, whose focus is the impact of climate change on the Bay.

The results are not encouraging. After coastal areas like Louisiana and southern Florida, the Chesapeake Bay region is the most vulnerable to coastal inundation, a scientific term that means land is submerged under water.

“It could be slow and gradual, or it could be episodic storm surges,” said Li, who works out of UMCES’ Horn Point Laboratory in Cambridge. The lab is an interdisciplinary, environmentally oriented research facility that is part of the University System of Maryland. His research is funded by the U.S. National Oceanic and Atmospheric Agency and the National Science Foundation.

Coastal inundation is not Li’s only Bay-related project. His research team of eight graduate students and postdoctoral fellows, which often works in collaboration with other scientists, is studying marine pollution from, for example, oil spills; the dynamics between estuaries and coastal oceans, particularly the rising salinity in the Chesapeake and Delaware bays that could affect the drinking water supply to Philadelphia; and plankton production in the Bay and North Carolina.

Li splits his time between research, which may find him sitting in front of his computer or on the water positioning test buoys and wind devices, and teaching graduate-level courses, mostly for University of Maryland, College Park, students, from an interactive, real-time setup at Horn Point.

Before joining UMCES in 2001, Li was a research scientist at the Institute of Ocean Sciences, a Canadian government facility in Victoria, British Columbia, where, the soft-spoken professor noted dryly, “They don’t get a lot of hurricanes.”

His first experience with a hurricane was 2003’s Isabel, which found him leaving a conference in Seattle early to get home to his wife and two sons.

“I’ve been fascinated by [hurricanes] since then,” said Li, who lives in Salisbury, a 40-minute drive to Horn Point, where he is part of a faculty and staff of some 125, he estimates.

Storm surges rising

In 2003, Hurricane Isabel, one of the deadliest and costliest weather events on the East Coast, had a storm surge of six feet. In 2050, the same storm could well have a surge of eight feet, Li says.

Moreover, in the 1950s, the East Coast experienced nine major storms and five hurricanes off the Atlantic Ocean. Now, the average is 15 major storms and nine hurricanes. The reason, Li says, is that as the ocean becomes warmer, it provides more energy for storms and hurricanes.

Throughout the 20th century, the mean sea level in the Chesapeake Bay rose 3 to 4 millimeters per year (3.1 mm equals about one-tenth of an inch), or about 1 foot compounded over a century, say Li and other scientists, based on observations from NOAA satellites and tide gauges.

Due to land subsidence — another scientific term that means the land is sinking — relative sea level rise in the Bay is about twice the global average.

Because of climate change and consequent results like glacier melt, the rate in the 21st century is accelerating two to three times that of the 20th century, Li contends. By the end of this century, he predicts the mean sea level in the Bay will be 3 feet above the current level.

The higher mean sea level is not the only factor in measuring coastal inundation. The other is the height of the high sea level, which is a combination of the mean sea level and the tide.

Thanks to the warming of the water, high tide is getting higher as well, Lee says. The tidal range in the Chesapeake Bay region, Baltimore and its tributaries could well increase by one-half to one foot over the course of the 21st century, in addition to the three-foot-higher mean sea level.

Put another way, as the Bay’s water level gets higher, there is less resistance when tides from the ocean move in, and the height of tidal waves increases.

Research on coastal inundation in Louisiana suggests that when the sea level is higher, the storm surge rises by a factor of 1.2 to 1.3 percent over past storm surges.

Li is finding similar results on the Bay, he said.

Climate change, also called global warming, remains a controversial topic. Scientists are developing models that study greenhouse gas and climate change. Some scientists debate the link between climate change and an increase in storms, though Li’s research doesn’t focus on that connection.

There’s also debate about acceleration in sea level rise because of climate change.

Just this week the Democratic governor of North Carolina let a watered-down bill, approved by the Republican-dominated legislature, take effect requiring that the state look at all available studies and data on the issue when it develops policies regarding sea rise.

A 2010 study by the Virginia Institute of Marine Science argues that the sea level rise in the Chesapeake Bay is modest and that the rate at which the land is sinking accounts, on average, for half of the relative sea rise.

Nonetheless, the sea level rise, combined with the locally high rate of land subsidence and an increasing coastal population, adds up to a “significant and growing threat,” according to the study’s researchers, who warn of the increased likelihood of coastal flooding during hurricanes and nor’easters in the Hampton Roads area of Virginia.

Part of Li’s research focuses on developing a system to predict storm surges and overland inundation. He has devised a model that can predict the height of a storm, where it will hit the hardest and how long the high water will last.

When he entered water and weather data for 2011’s Hurricane Irene, the model correctly predicted exactly how the storm would play out.

Plotting storms house by house

Dr. Sophie Wang, a computer science professor at Salisbury University, is collaborating with Li on visualization software for his model.

Using Li’s model for data on wind speed and water levels, combined with data from local governments on building regulations and housing heights, Wang uses Google Earth to predict neighborhood by neighborhood, street by street and house by house what different weather events would look like. A test application of the technology for Cambridge during 2003’s Hurricane Isabel turned out to be accurate.

“If you have a tropical storm of a certain magnitude, this is what will happen,” Wang said. “If you have a waterfront house, this is where the sea level will be.”

The software is still in the development stage and isn’t ready for commercialization. But Wang and Li are already getting inquiries from, among others, insurance companies and geographic information systems companies.

As a member of the House’s Environmental Matters Committee, Del. Dana M. Stein (D-Dist. 11) of Pikesville has heard testimony on climate change and become familiar with the topic.

He points to the 2008 Maryland Climate Action Plan, developed by the governor-appointed Maryland Commission on Climate Change, which reports to Gov. Martin O’Malley (D) and the General Assembly. Among the plan’s goals is to reduce the state’s vulnerability to weather events.

“Li’s findings are very credible” in that regard, said Stein, who has researched the topic himself for an apocalyptic novel he wrote set in a globally warmed future.

Li’s model can be used for coastal planning and designing emergency response strategies. Both the Maryland Department of Natural Resources and the Maryland Emergency Management Agency are in the process of doing so, according to officials.

Zoe Johnson, of DNR’s Office for a Sustainable Future, has collaborated with Li on a number of projects over the years.

“His research helps us better understand the magnitude and range impacts,” said Johnson, whose office helps coastal communities plan for sea level rise and coastal storms.

Likewise, Ed McDonough, MEMA spokesman, says Li’s finding on stronger and more frequent storms is a consideration in the agency’s planning process. In fact, independent of Li’s research, McDonough says that MEMA in its response to hurricanes and storms is anticipating a greater level of flooding than in the past because of sea level rise.

“There are places in western Dorchester County, like Hooper Island, that are one to five feet above sea level, so even minor changes in that level and the way storms hit could impact a large land mass,” said McDonough, who added that Li’s research applies not only to the Chesapeake Bay but to coastal areas like Ocean City, Assateague Island and Worcester County’s bays.

Said Li: “People like waterfront properties because of the beautiful views, but they’re not thinking of the risk.”

A quote from Ed McDonough, spokesman for the Maryland Emergency Management Agency, should have made reference to Hooper Island in Dorchester County.