Record-breaking Sahara rain | News | Al Jazeera

Record-breaking Sahara rain

A year's worth of rain fell in southern Algeria in just five days.

by
    Record-breaking Sahara rain
    The dramatic volcanic valley of Assekrem in the rain catching mountains of southern Algeria [Getty]

    Over a period of five days, the southern Algerian city of Tamanrasset has received 45mm of rain. That is a remarkable amount of rain simply because it is more than is expected in an entire year.

    Tamanrasset sits in a wadi, or valley, of the Ahhagar massif, a large volcanic mountain range in the Sahara Desert. Much of this massif is a national park and contains the famous hermitage site of Assekrem.

    Assekrem is high in the mountains, 2,700 metres above sea level, and has an annual rainfall of 118mm. Surprisingly, this is almost three times as much as Tamanrasset which sits at a lower 1,400 metres.

    Assekrem, in the same five days between March 19 and 24, exceeded its annual rainfall expectation, with 130mm caught in the rain gauge. This represents 110 per cent of average annual rainfall, as calculated from a respectable 50-year archive.

    Mountains are good producers of rain, as they force air to rise, cool and release its moisture. In the Sahara though, it is usually too dry to have enough moisture to release.

    This March, enough water vapour made it from the Atlantic, across the western desert, to make the Algerian wadis green. Satellite pictures still show the long streak of cloud, stretching from Guinea to Libya, which gave the rain.

    The rain has now stopped in the Ahhagar mountains, but there are still unusually early showers showing up in the sahel, in Niger and Mali.

    SOURCE: Al Jazeera


    YOU MIGHT ALSO LIKE

    Interactive: Coding like a girl

    Interactive: Coding like a girl

    What obstacles do young women in technology have to overcome to achieve their dreams? Play this retro game to find out.

    America's Guns: Secret Pipeline to Syria

    America's Guns: Secret Pipeline to Syria

    How has the international arms trade exacerbated conflict in the Middle East? People and Power investigates.

    I remember the day … I designed the Nigerian flag

    I remember the day … I designed the Nigerian flag

    In 1959, a year before Nigeria's independence, a 23-year-old student helped colour the country's identity.