Hurricane Eta swept across central Florida on 12 November 2020, causing eleven fatalities, in addition to the 178 it had already claimed in Central America, in addition to causing widespread flooding and causing about a billion dollars' worth of damage to property. After the storm had passed it was discovered that high tides brought on by the hurricane's storm surge had scoured the beach at the Fort Matanzas National Monument in St John's County on the east coast of Florida, exposing the remains of a ship that had been burried by the sand.
The site is now being investigated archaeologists from the St. Augustine Lighthouse Archaeological Maritime Program and students from Flagler College, who have determined that the remains probably belong to the Caroline Eddy, an American merchant ship which sank in the area on 29 August 1880, after becoming caught in a storm.
Tropical storms, known as hurricanes in the Caribbean, are caused by solar energy heating the air above the oceans, which causes the air to rise leading to an inrush of air. If this happens over a large enough area the inrushing air will start to circulate, as the rotation of the Earth causes the winds closer to the equator to move eastwards compared to those further away (the Coriolis Effect). This leads to tropical storms rotating clockwise in the southern hemisphere and anticlockwise in the northern hemisphere. These storms tend to grow in strength as they move across the ocean and lose it as they pass over land (this is not completely true: many tropical storms peter out without reaching land due to wider atmospheric patterns), since the land tends to absorb solar energy while the sea reflects it.
Despite the obvious danger of winds of this speed, which can physically blow people, and other large objects, away as well as damaging buildings and uprooting trees, the real danger from these storms comes from the flooding they bring. Each drop millibar drop in air-pressure leads to an approximate 1 cm rise in sea level, with big tropical storms capable of causing a storm surge of several meters. This is always accompanied by heavy rainfall, since warm air over the ocean leads to evaporation of sea water, which is then carried with the storm. These combined often lead to catastrophic flooding in areas hit by tropical storms.
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