For example, significant cooling and strong dynamical effects after the Laki event and other high-latitude eruptions are believed to have caused decreased flow of the Nile River in Egypt and weakened African and Asian monsoons based on climate model simulations, with potentially very significant impacts on food and water supplies.

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Balloon rides are a popular way to see the numerous ancient sites which line the banks of the River Nile at Luxor, in the south of Egypt, such as the temple of Karnak and the royal tombs in the Valley of the Kings.

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But the ancient rite, common in the Nile Valley and other parts of Africa, has remained particularly prevalent in Egypt.

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The Blue Nile originates in the country's Lake Tana and flows hundreds of miles north into Sudan and then Egypt before eventually flowing into the Mediterranean.

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Usually, he and Marchand dream up their thongs and wedges while floating down the Nile, but this year, because of the unrest in Egypt, they relocated to Brazil.

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Dozens of relatives of those killed in Egypt's demonstrations gathered outside the court, state-run Nile TV reported.

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Across all of Africa the impact of human activity is clear - whether in the newly irrigated areas created by the waters of the Nile, turning huge areas of the desert around Egypt's lake Nasser green, or the urban sprawl of Dakar, across the Cap Vert peninsula in Senegal.

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