Saturday, 27 July 2019

Fifteen dead in Morocco landslide.

Fifteen people have been confirmed dead after a minibus was buried by a landslide at Tuk Al-Khair in the Atlas Mountains to the south of Marrakesh in Morocco on the evening of Wednesday 24 July 2019. The vehicle was covered by about 20 m of soil and debris, and it took rescuers until Friday 26 July to dig down to it. The dead have been described as eleven women, three men, and a child; there were no survivors. The incident is reported to have been triggered by a flash flood following heavy rain in the area. Landslides are a common problem after severe weather, 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.

Rescue workers searching for a minibus buried by a landslide at Tuk Al-Khair in the Atlas Mountains of Morocco this week. IANS/Xinhua.

Like many desert areas the Atlas Mountains, while generally arid, is prone to occasional severe flooding. This stems from two causes; firstly the arid climate prevents the development of a thick soil layer which would be expected in less dry areas, so that in much of the area (non-porous) bedrock is either exposed or close to the surface, and secondly the hot climate leads to heavy evaporation from nearby Atlantic Ocean, so that if the wind changes direction and brings water-laden air to the area, it brings a lot of precipitation with it. This combination of heavy rainfall and low ground absorbency leads to large amounts of water at the surface, typically moving downhill at some speed. Dry channels or ravines through which these sudden floods are channelled, can be particularly dangerous at these times, particularly as they often appear to resemble natural pathways or even camp sites to people unfamiliar with the climate.

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