Grenada in the Future

Unique Physical Geography of Grenada

Grenada is a volcanic island, part of the Lesser Antilles island arc in the Caribbean. It is located along the Lesser Antilles subduction zone where the oceanic crust of the South American plate is being subducted under the Caribbean plate. The tectonic activity is responsible for the formation of the island and its volcanoes. The two most important volcanoes are Mt. Saint Catherine and Mt Kick 'em Jenny. Mt. Saint Catherine is a currently dormant stratovolcano and the highest point of the island. Mt Kick 'em Jenny is an active submarine volcano located about 8 km north of Grenada. Grenada has a mixed topography of high mountains and low valleys. These valleys contain rivers that flow out in a radial drainage pattern. 

Photo taken in December 2013 during my cruise to the Caribbean. In the image you can see some of Grenada's geographical features. 

10,000 years from now

10,000 years from now Grenada will be quite different. Due to climate change, sea levels have been rising about .13 in (3.2 mm) per year. Assuming that this continues, sea levels will be 108.3 ft. (32 m) higher in 10,000 years. Grenada's highest elevation is 840 ft., but otherwise varies from less than 300 ft. to 600 ft. about sea level. Due to this some of Grenada will remain above land, but most of its coastline will become submerged. Drowned river valleys or rias will become characteristic of Grenada since the rising seas level will flood and fill in the valleys located on the island. 

Retrieved from http://www.teara.govt.nz/en/photograph/13012/a-drowning-landscape
Image of a ria. Grenada may look more like this on a smaller scale in 10,000 years as sea levels rise.

1,000,000 years from now

In 1,000,000 years Grenada will change even more. All the Lesser Antilles including Grenada started out as submarine volcanoes. More submarine volcanoes will form around the area as the tectonic plates continue to move. Due to continued volcanic activity Mt. Kick 'em Jenny will be uplifted and eventually become connected to Grenada. The volcano has been known to erupt about every 10 years which means that it will erupt about 100,000 times in the next million years if it continues to be active. Each eruption forces the volcano more and more to the surface expanding it. Kick 'em Jenny may become connected to the rest of Grenada over time.

Due to the pattern of glacial and interglacial periods, sea levels will fall again exposing this formed land between Grenada and the currently submarine volcano. 

Retrieved from http://en.wikipedia.org/wiki/Kick_%27em_Jenny
Image showing depth of Mt. Kick 'em Jenny, 8 km of the coast of Grenada. 

100,000,000 years from now

For the next 100 million years the plates will continue moving resulting in continental drift. Even relatively small land masses like Grenada will be affected. The rate of subduction in the Lesser Antilles island arc is Caribbean is about 2 cm per year. In 100 million years it will have been subducted 2,000 km. This along with the movement of the other plates will eventually create another super continent like Pangaea. Due to continental drift these super continents form every few hundred million years and then break up again. In this next scenario the Caribbean Sea will shrink as the plates move west setting the Islands on a collision course with the main land. In this scenario Grenada will also move closer to the continent as the Caribbean Sea closes and the Atlantic Ocean expands. 

Retrieved from http://earthdharma.org/2010/01/
Map of tectonic processes in the Lesser Antilles including tectonic plate boundaries, rates of movement and active volcanoes.

Reference:
http://ocean.nationalgeographic.com/ocean/critical-issues-sea-level-rise/
http://en.m.wikipedia.org/wiki/Geography_of_Grenada
http://www.uwiseismic.com/general.aspx?id=27     Mount kick em jenny 
http://www.renewton.plus.com/geology/talks/2012/Tale%20of%20two%20islands/index.htm
https://www.youtube.com/watch?v=uQ91AxUqHck 
http://www.geo.mtu.edu/~raman/papers2/WadgeGeolVol.pdf