http://www.pressofatlanticcity.com/top_three/story/7522904p-7423344c.html

Warming puts local shores at risk

By ROB SPAHR
(Published: December 15, 2007)
Click to view Sea Level graphic
LITTLE EGG HARBOR TOWNSHIP - Two years ago, Rutgers University Professor Ken Able made a surprising discovery as he emptied traps used to monitor fish at the university's Marine Field Station.

Most of the fish inside the traps were gag groupers - a species of fish that typically lives in coral reefs - which was odd, considering that the nearest coral reef is hundreds of miles south of New Jersey.

For Able, this was a glaring indication that global warming is altering New Jersey's waterways and the marine life that calls them home.

"Generally, some southern species always show up in the fall when water temperatures are the warmest, but since about 2000 we've seen an obvious increase in the amount of these species in our waterways," Able said.

Able is one of a handful of Rutgers scientists who, as part of their daily duties, chronicle the effects of global warming on the New Jersey coast from field stations across the state.

The Little Egg Harbor Township field station is one of the most important in that group.

"We've been sampling larval fish once a week for 18 years from right inside the Little Egg inlet, so we have one of the best data sets on the East Coast of the United States," Able said, adding that scientists at the station are currently tracking 71 southern species, including Atlantic croaker and silver perch.

"This estuary is really well protected and undisturbed. That kind of landscape benefits us, because the area we collect data from is so close to the station it enables us to collect the data easier and more often."

The field station's staff also has recorded water temperatures since 1976; Able says the information shows the average annual temperature of the region's waterways has become "clearly much warmer" over time.

According to this data, the region's average water temperature has increased by two degrees Celsius just since 1994.

Even though two degrees may not seem significant, Michael Kennish, the research coordinator for Rutgers' Institute of Marine and Coastal Sciences, said that if temperatures were to increase five degrees, it would melt all of the world's glaciers.

While warmer temperatures play a large role in the types of marine life found in the waterways, Kennish said the warmer climate also will change the face of the state's coastline.

As temperatures increase, Kennish said, water levels rise and threaten the coast.

"In the past 100 years, the sea level in New Jersey has risen about seven inches because of warming, but the sea level actually rose a total of 15 or 16 inches because the shoreline in our area is sinking due to the sediment beneath it compacting," Kennish said. "In the next 50 to 100 years, we project global warming will cause the sea level to rise at a much faster rate, somewhere between 25 to 40 inches. It could be even greater, but in our area I expect the level will be closer to 36 inches."

If the sea level increases 36 inches, Kennish said, it would remove an area the length of a football field from New Jersey's beaches, which would put many of the state's popular vacation destinations in harm's way.

"We're looking at big-time trouble in New Jersey because we're actually moving people to the shore instead of away from it. Our shore is almost completely developed, and yet people are still moving to it," Kennish said, adding that coastal communities would experience increased flooding and would be more susceptible to major storms, which he said would become more frequent as temperatures increase.

There are two possible, but flawed, ways to protect communities situated on or near beaches, Kennish said.

The first is a "soft" approach that requires the replenishment of beaches and construction of dunes, similar to this year's beach-replenishment project on Long Beach Island.

However, Kennish said, usable sand is becoming harder to find, and the cost to do these projects is often extremely high - eventually it may no longer be cost-effective to do them, he said.

The second possibility is a "hard" approach, which would entail building permanent structures, such as sea walls, along the coast. Municipalities in Monmouth County, including Sea Bright and Monmouth Beach, already have implemented this approach.

But while this could protect the properties next to the sea walls, Kennish said, homes on the bay side of the barrier islands and the salt marshes that line the bays would still be at risk.

"Currently the salt marshes are growing at a faster rate than the sea level, but when that changes, the water will drown the marshes. This would be disastrous for bayfront communities like Tuckerton, Little Egg Harbor and Barnegat," said Kennish, who said salt marshes along the Delaware Bay in Cumberland and Salem counties are eroding at a rate of 10 feet per year.

Kennish said the peninsula where these scientists do their research could be one of the first areas to go because of the salt marsh it is built on.

This year, the field station had to demolish a 40-year-old radio tower because water eroded the salt marsh beneath it and damaged the tower's concrete base.

"New Jersey is a very flat state. If the water rises three feet, there is really nothing in place to stop it from going inland," said Kennish, who also works out of the Jacques Cousteau National Estuarine Research Reserve in Little Egg Harbor Township.

Kennish said Rutgers scientists will be "huge players" in finding ways to decrease the impact global warming has on New Jersey's coast.

"The front line will be our beaches. That is where most of the effort, and money, will likely go," Kennish said. "But it would be a mistake to neglect the salt marshes on the bay side, because that is where the biggest problem will be."

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