Tropical Storm Magi (known in the Philippines as Tropical Storm Agaton) passes across the Philippines on Sunday 10-Monday 11 April 2022, resulting in at least 43 deaths, a number that is likely to rise due to the large number still missing. The worst affected area is the island of Leyte, where 26 people are known to have died (14 in a single incident when a mudslide engulphed the village of Mailhi on the southern part of the island) with another 26 still missing. Another three deaths have been recorded in Negros Oriental Province, and three more on Mindanao Island.
Tropical storms 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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