Sea Level in the Chesapeake Bay is rising only about half as fast as the global average rise rate, however the local subsidence more than makes up for it. Dr. John Boon, who is the study’s lead author, has previously warned of the long term impacts of the sea-level rise in Hampton Roads especially in light if the increased likelihood of coastal flooding during hurricanes and nor’easters. In Dr. Boon’s report, it states the different between absolute sea level, a measure of the volume and mass of ocean water, and relative sea level, the level of the ocean surface measured relative to land (and more specifically a tide gauge). It is noted that for the Chesapeake Bay moderates the rates of absolute sea-level rise; when combined with locally high rates of land the subsidence and the increasing coastal population it adds up to a significant and growing threat.
The Chesapeake is naturally saltier near its mouth and fresher near the inflow of rivers. The salinity change that was found was consistent with the trend determined from the statistical analysis; supporting the hypothesis that sea-level rise has significantly increased salinity in the Bay. However, the Penn State researchers note that historical salinity data is limited and sedimentation reshapes the bed of the Bay. There are also cyclical effects partially due to Potomac River flow, Atlantic Shelf salinity and winds. The salt content affects jelly fish, oysters, sea grasses and many other forms of aquatic life. The Chesapeake Bay is a beautiful place, used for recreation and for people's livelihoods. It is a real jewel on the East Coast and changes in salinity can alter its uses. Our research improves our understanding of the influence of climate change on the Bay and can therefore be used to improve costly restoration strategies.
Coastal habitats in the Chesapeake Bay region, near Washington D.C., will be dramatically altered if sea levels rise globally about two feet by the end of the century, which is at the low end of what is predicted if global warming pollution remains unaddressed. Because of this problem the region would lose more than 167,000 acres of undeveloped dry land, 58% of the beaches along ocean coasts, and 69% of estuarine beaches along the bay. There is to be more than 161,000 acres of brackish marsh and more than half of the regions important tidal swamp.
The Chesapeake Bay provides critical stop over and wintering habitat for more than one million migratory waterfowl, including the canvasback, mallard, redhead, American black duck, tundra swan, and Canada goose. The bay’s coastal marshes are home to great blue heron, snowy egret, and other familiar birds, and they provide important food sources and nesting sites for numerous songbirds, mammals, reptiles, and amphibians. The region’s beaches support some of the largest populations of shore birds in the western hemisphere such as red knot and piping plover, and are a critical nesting site for sea turtles. The Chesapeake Bay sustains recreational and commercial fisheries worth billions of dollars annually, including popular blue crab, rockfish, menhaden, and eastern oyster.
This research has helped the scientists to improve their understanding of the influences of the climate changes on the Bay and hopefully can and will be used to improve the costly restoration strategies.
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