The word peninsula derives from Latinpaeninsula, from paene 'almost' and insula 'island'. The word entered English in the 16th century.[3]
Definitions
A peninsula is generally defined as a piece of land surrounded on most sides by water.[8][9]
A peninsula may be bordered by more than one body of water, and the body of water does not have to be an ocean or a sea.[10] A piece of land on a very tight river bend or one between two rivers is sometimes said to form a peninsula, for example in the New Barbadoes Neck in New Jersey, United States.[8] A peninsula may be connected to the mainland via an isthmus, for example, in the Isthmus of Corinth which connects to the Peloponnese peninsula.[11]
In the case of formation from glaciers (e.g., the Antarctic Peninsula or Cape Cod), peninsulas can be created due to glacial erosion, meltwater or deposition.[14] If erosion formed the peninsula, softer and harder rocks were present, and since the glacier only erodes softer rock, it formed a basin.[14] This may create peninsulas, and occurred for example in the Keweenaw Peninsula.[14]
In the case of formation from meltwater, melting glaciers deposit sediment and form moraines, which act as dams for the meltwater.[14] This may create bodies of water that surround the land, forming peninsulas.[14]
If deposition formed the peninsula, the peninsula was composed of sedimentary rock, which was created from a large deposit of glacial drift.[15][16] The hill of drift becomes a peninsula if the hill formed near water but was still connected to the mainland, for example during the formation of Cape Cod about 23,000 years ago.[17][18]
Marine transgressions (changes in sea level) may form peninsulas, but also may affect existing peninsulas. For example, the water level may change, which causes a peninsula to become an island during high water levels.[25] Similarly, wet weather causing higher water levels make peninsulas appear smaller, while dry weather make them appear larger.[26]Sea level rise from global warming will permanently reduce the size of some peninsulas over time.[27]
Uses
Peninsulas are noted for their use as shelter for humans and Neanderthals.[28] The landform is advantageous because it gives hunting access to both land and sea animals.[28]They can also serve as markers of a nation's borders.[29]