Although the Bay is versatile and resilient, it is also vulnerable, as recent storms and surges have shown. If sea levels rise, it will bring yet another round of change to the Rhode Islanders who live so close to this essential body of water. And to the many species of wildlife who also call the Bay home. More than kinds of birds have been seen here.
Over the years there have been many wonderful maps, photographs, and satellite images of Narragansett Bay. Of course, the Native Americans knew it very well for thousands of years before Roger Williams came here. Many of the words he gathered from the Narragansett describe their lives near the Bay — the fish and shellfish they ate, the boats they built, the wampum they made from seashells.
Roger deliberately chose a place near the Bay for his trading post, so he could travel there by water or land. He also came to Providence by water, as we can see in the City Seal. A complicated sequence of marine ingression and isostatic rebound flooded and emptied the landscape. A fresh water proglacial lake called by geologists Lake Narragansett formed about 15, B.
Then salt water filled the valley, as rising sea levels permanently flooded the area. Tides are measured with pressure-sensing tide gauges. In shallow water, sound waves are used to measure water height by precisely measuring the travel time of the waves. In deeper water, tides are measured with pressure-sensing tide gauges that are placed on the ocean floor to measure water height.
The bay's tides are semi-diurnal, meaning that the region experiences two high and low tides that occur daily. The tides range in height from 1. The differences in water depth between high and low tide averages to about 4 feet 1.
The lunar, semi-diurnal M2 tide occurs at a period of The watershed's neap and spring tides occur every In Narragansett bay, the tides show a distinct double-peak flood during high tide and single peak ebb during low tide.
The movement of water within a system is its circulation. Estuaries are given a classification depending on the pattern of their circulations. The circulation classification can be well-mixed, partially mixed, salt wedge, or Fjord-type. For Narragansett, the circulation is mostly well-mixed, however, the Providence River does show some vertical stratification. Narragansett Bay circulation is made up of forces provided by the winds, tides and changes in water density within the watershed.
Within estuaries such Narragansett, its circulation is the result of the flow of fresh water at the head interacting with salt water at the point where the bay meets the open ocean. It has a volume of over billion gallons. It has a mean depth of 26 feet, and the deepest point of the bay is feet. The side of the bay is miles long. There are several birds that visit the bay like piping plover, raptors, osprey, and bald eagle. During the spring and fall, several traveling birds spend time on the side of the water.
The daily flow of water into the Narragansett bay from all sources around the world is about 2. It is known that over 12 million people visit Narragansett bay yearly majorly as tourists. The fishes that are mostly sold from the Narragansett bay are winter flounder, summer flounder, tautog, bluefish, scup, lobster, weakfish, alewife, Atlantic herring, black sea bass, cod, and menhaden. The wastewater treatment plants are unable to handle all of the water due to combined sewer and storm drains and raw sewage is often discharged into the bay during heavy rainfall.
Seasonal visitors to Narragansett Bay include harp seals, gray seals, harbor seals, harbor porpoises, and dolphins. Seal watching tours are available from November to April aboard two different educational vessels via Save the Bay.
In the spring and fall migratory birds spend time in Narragansett Bay. Shorebirds that visit the coast of Narragansett Bay including the piping plover endangered , raptors, osprey, and bald eagles.
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