Campobello Island and Sea Level Change
-
Difficulty:
-
-
Terrain:
-
Size: 
(not chosen)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
We have all heard about global warming and climate change but this earthcache will help you understand the effects of sea-level rise along the shores of Campobello Island and the effects on its parks both past and future.
Welcome to the 2.800-acre Roosevelt Campobello International Park, established in 1964. The Park's main attraction is the Roosevelt Cottage, while the less-visited Natural Area - with its coastal headland, rocky shore, sphagnum bog, field, forest and beaches - makes up most of the area of the park and is a special an attraction to the outdoor explorer and to those interested in the geology of natural areas. The Roosevelt Cottage offers the visitor a view of a submerged coast that has had a profound impact on the aesthetic character of the location.
Research studies show that raising and lowering of the land mass and by actual changes in the amount of water in the oceans may cause apparent changes in sea level. As time passes, and as sea levels rise with respect to the landmass, the coast is submerged or drowned. Global warming impacts various conditions on our Earth, one result being changes in sea level. Scientists have recently discovered that the sea level along the coast of New Brunswick has risen 50 cm since 1750 A.D. and along the coast of Nova Scotia as much as 60 cm. This gradual sinking of the coastline or subsidence is caused by the lingering effects of the melting of the ice sheet that covered this area during the last ice age.
If we were able to go back in time to the last glacial period, we would be amazed at what we would witness. This area was covered with a thick layer of glacial ice with a massive weight. This weight forced the land to be compressed and pushed downward. By 13,000 years ago, the ice had retreated to the limit of the seawater submergence, in places 100 miles from the modern coast. As the ice retreated, the continental crust floated up as the ice melted. As the land rose, it made the sea retreat. By 12,000 years ago this area was above sea level; by 11,000 years ago the land was as much as 150 feet above current sea level and in some places as much as 300 feet above sea level (some researchers place the level as high as 485 feet). As the ice continued to melt and add water to the sea, it rose until 2000 years ago when the level was about the same as it is today. This history of sea-level changes has been recorded in sedimentary deposits and the geomorphology (shape) of ancient coastal terraces, cliffs, and deltas found both above and below present sea level.
The recent increase in sea-level rise along the coast is unprecedented in the past millennium. It has taken place in two distinct steps. At the end of the 18th century the sea level rose as a result of the natural cyclic climatic warming. But in the 19th century, sea level didn't rise much at all, that is until the beginning of the 20th century, when sea level took off again, in tandem with global and hemispheric temperature rise.
What impact does the rise have on the coast? None if it is rock bound. However, there are many stretches of bluffs of soft sediment, and beautiful beaches in this area. As sea level rises against a coast of tough, glacially smoothed rocks, erosion is very slow, and the gradual rising primarily produces unnoticeable shoreline changes. But on soft shorelines the wave and current erosion produces shoreline retreat much more rapidly than the simple sea-level invasion. Additionally, when homeowners, developers, or larger-scale engineering changes are introduced, vegetation is often stripped and the natural cycles are interrupted. This shoreline is often protected by riprap, artificial fill of boulders and quarried stone. This has slowed the erosion rate at this site, but there are hidden effects to the tidal flat fronting the site, and to neighboring stretches of shoreline.
Just up river at the Saint Croix Island International Historic Site, where there is evidence of the first permanent European presence in Northern North America, researchers fear that much of the historical information may have been lost to the rising sea as parts of the Island fell into the water. Besides these obvious effects of sea-level rise, the careful observers in many parts of New Brunswick and Maine can find other evidence. Rising sea level has resulted in drowning of sloping upland margins. This has drowned coastal forests, resulting in grey, dead trees standing in ghostly ranks along the margins of salt marshes.
The most recent global climate modeling by the U.S. Environmental Protection Agency has predicted sea levels will range from a low of 0.5 m (1.6 ft) to a high of 3.5 m (11.5 ft!) above present by the year 2100. Scientists and planners have known for more than a decade that the sea level is rising. In 1995, the EPA estimated that a 2 to 3-foot sea-level rise was possible over the next several generations and communities started to plan for a future. With this new study, many communities are rethinking their plans. In any discussion of rapid changes of climate and sea level, the ultimate question is: what can we really predict for the future sea level rise?
This earthcache can be approached from a wide variety of locations. The posted coordinates are at the center of a section of submerged coast that no doubt the Roosevelt family greatly appreciated. Research shows that the water here has risen more then 5 feet since 1900. As you look at the shore you should be able to identify evidence of this recent rise in sea level. Remember this is an earthcache, so there is no container - just an earth science lesson at a beautiful natural feature. To log this cache, you must post a photo of yourself or your hand with your GPS showing a view of your evidence. In your log, you will need to give a description of the evidence that you have found, the coordinates of the evidence and the distance to the posted coordinates. Please take the time to describe why you find this location special so that others might have the same experience.
The Roosevelt Campobello International Park has a very informative brochure that can be found at: www.fdr.net/pdf/geology.pdf
Additional Hints
(No hints available.)