Tropical Storm Ana kills at least 46 people in Madagascar, Mozambique, and Malawi.

Tropical Storm Ana is now thought to have killed 39 people on Madagascar, which it swept across on the weekend off 22-23 January 2022. The storm brought with it heavy rains, causing many rivers to burst their banks, with flooding being particularly severe around the island's capital, Antanarivo, where around 55 000 people are thought to have lost their homes. 

 

Flooding in the 67 Hectares neighbourhood of Antananarivo on 24 January 2022. AFP.

The storm made landfall on the African mainland on Monday 24 January, in Nampula Province, Mozambique, and has caused severe flooding in the Zambezi River Basin in Mozambique, where at least three people have died in Zambezia Province, with 66 people injured and about half a million displaced by flooding across Zambezia, Nampula and Sofala provinces. In neighbouring Malawi, four people are reported to have died, with around 30 injured and many more displaced by flooding. Affected areas of both countries are suffering widespread power outages and are likely to run short on food and drinkable water rapidly.

 

Storm damage at Topuito in Nampula Province, Mozambique, on 24 January 2022. Songo9Dades.

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.

 

The formation of a tropical cyclone. Natural Disaster Management.

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.

 

The formation and impact of a storm surge. eSchoolToday.

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Zimbabwean bride marries five days after loosing arm to Crocodile.

Zimbabwean bride Zanele Ndlovu, 25, married fiance Englishman Jamie Fox, 27, in a chapel at the Mater Dei Hospital in Bulawayo, five days after being attacked by a Nile Crocodile, Crocodylus niloticus, while the couple were canoeing on the Zambezi River. The 5 m animal leaped onto the boat unexpectedly from clear water, seizing Ms Ndlovu by the arm and rolling, a method which uses the Crocodile's mass to inflict maximum damage on it's prey. The couple were hauled from the water by employees of the boating company and airlifted to hospital, but the arm could not be saved.

Zanele Ndlovu, at her wedding on 5 May 2018, five days after losing an arm in a Crocodile attack. AP.

The Zambezi is home to a large population of Nile Crocodiles, Crocodylus niloticus, which are popular with tourists. Nile Crocodiles are large animals, reaching about five meters in length, and are ambush predators capable of taking large prey, including, on occasion, Humans. The animals are thought to be at their most dangerous around September on the Zambezi, when the water is lowest, and females are guarding eggs buried in nests by the river, however they can clearly be dangerous at other times of year if provoked.

Nile Crocodiles are considered to be of Least Concern under the terms of the  International Union for the Conservation of Nature’s Red List of  Threatened Species, but are still protected in many countries, due to historic hunting which decimated populations in many areas. However, the rising number of attacks on Humans by the animals has led to calls for regulated hunting to be introduced to control the population.  

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Woman killed by Crocodile in Lusaka Province, Zambia.

A 57-year-old woman has been killed while on a fishing trip on the Zambezi River in Lusaka Province, Zambia. Sophia Njovu of the village of Muchingamire was dragged into the river by the animal on Saturday 23 September 2017, near Chiawa in Kafue District. This was the fifth Crocodile-related death in the country in the last two years. In a separate incident, a man was injured by another Crocodile while swimming in the Zambezi near Kanyachi in Chavuma District of Northwestern Province. Boyd Funga, 33, was attacked on Friday 22 September, and is being treated in the Chavuma Mission Hospital for injuries to his legs and chest.

The approximate location of the 23 September 2017 Chiawa Crocodile attack. Google Maps.

Zambia is home to two Crocodile species, the Nile Crocodile, Crocodylus niloticus, and the Slender Snouted Crocodile, Crocodilus cataphractus, though the later is found only around Lake Bangweulu and the Luapula River, so the Zambezi River attacks were almost certainly carried out by Nile Crocodiles. Nile Crocodiles are large animals, reaching about five meters in length, and are ambush predators capable of taking large prey, including, on occasion, Humans. The animals are thought to be at their most dangerous around September on the Zambezi, when the water is lowest, and females are guarding eggs buried in nests by the river.

A Nile Crocodile, Crocodylus niloticus, in South Luangwa National Park, Zambia. Hana Yariv/Wikimedia Commons.

Nile Crocodiles are considered to be of Least Concern under the terms of the  International Union for the Conservation of Nature’s Red List of  Threatened Species, but are still protected in many countries, including Zambia, due to historic hunting which decimated populations in many areas. However, the rising number of attacks on Humans by the animals has led to calls for regulated hunting to be introduced to control the population.

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