Coastal shorelines are dynamic places. Wave and wind action is constantly acting upon the loose soil materials that were deposited by the glaciers 14,000 years ago. Even bedrock shorelines are worn down, albeit slowly, by the constant battering of waves.
The shoreline the first Rhode Islanders laid eyes upon was likely quite different from the shoreline we see today. Perhaps you have noticed this in your lifetime... coastal areas from your childhood may be hardly recognizable today. One can easily look at the changes that have occurred to the beach at the Ocean Mist in South Kingstown. There was once a wide beach, complete with volleyball court, beyond the deck. Today, there is a beach only at low tide, and high tide reaches beneath the deck.
How much longer before the sea claims the Ocean Mist?
Coastal erosion typically gains center stage following major storms. Here's a picture of damage and dramatic erosion at Roy Carpenter's Beach in South Kingstown following Hurricane Sandy:
Continued erosion at Carpenter's Beach has forced the relocation of beach cottages.
Erosion of the coastline causes millions of dollars in property damage and can compromise septic systems. Did you notice the old cesspool that has been exposed next to the Ocean Mist in the picture above? Because business, habitat, and homes are at stake, the RI CRMC has created shoreline change maps for all of the RI's coastal areas. These maps use aerial photos to show water lines from 1939 (red), 1975 (yellow), and 2005 (green). Using these data, erosion rates have been calculated (yellow digits) along beach transects to provide an estimate on how much the shoreline has eroded over a 30-year period. These maps are used in permitting coastal zone projects. Typically, new construction must be beyond a 30-year future projection of the current shoreline.
Your Task:
The shoreline of Goddard Park is not in danger of being developed, but it does face a surprisingly high amount of erosion. Your task is to use the shoreline change map above to calculate how long it will take for this eroding headland to erode beyond the current walking trail. To log this Earthcache, please complete the following:
1. Using a tape measure, measure the distance from the seaward edge of the bluff to the landward edge of the trail.
2. Use the measurement from 1 and the yearly erosion rate on the map to calculate how many years it will take for the bluff to erode to the edge of the forest, thus destroying the current walking trail.
3. Examine the area and develop a hypothesis as to why this area is so prone to erosion.
Once you have completed this assignment, please email me your answers prior to logging.
Congrats to ritell for the ftf!