More than fifty people are thought to have died in a series of landslides in Guatemala, with around half the deaths associated with a single event in the town of San Cristobal Verapaz, where a mudslide swept away about 20 houses. Elsewhere, another ten people were killed in a landslide in Huehuetenango Department, two children died when their home was destroyed by a landslide in Santa Barbara Department in the north of the country and a second pair of children died in another landslide incident in Quiche Department, also in the north, while a third pair of children died in a separate landslide in the south of the country. Another landslide in the south has left one person dead and another two missing, while another person died in a landslide close to Guatemala City. All of these landslides have been brought on by heavy rains associated with Hurricane Eta. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. Despite not being directly hit by the storm, Guatemala has suffered badly because of it, with flooding across much of the country, and at least five major bridges, and numerous roads, swept away.
Across central America about 70 people are thought to have died in incidents related to Hurricane Eta, which was a Category 4 Hurricane when it made landfall, bringing with it winds of up to 225 km per hour, to the south of the city of Puerto Cabezas. Two people are known to have died in Nicaragua as a result, and two in Honduras. In Panama, five people were killed when a landslide buried their homes in Chiriqui Province, close to the border with Costa Rica, while in Costa Rica a 71-year-old American citizen and his 51-year-old Costa Rican wife died in a landslide at Coto Brus in Puntarenas Province. El Salvador has also reported a number of landslides, though no fatalities at the current time.
Hurricane Eta has lost energy as it has passed over Central America, and been downgraded from a hurricane to a tropical storm, but it is expected to travel northwest over the next few days, gaining strength again as it passes over the Caribbean, and potentially threatening the populations of Cuba and Florida. The casualty rate was probably been kept down by the evacuation of about 20 000 people from its path in Nicaragua, and Honduras.
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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