This river and rain runoff, combined with strong onshore winds, has led to high levels of sea pollution.

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Aiding in the evaporation are the prevailing onshore northwesterly winds during the day (shamal), and the offshore southeasterly winds during the night.

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They are believed to be 60 million to 80 million years old, made of sand pushed inland over the eons from the coast by Atlantic Ocean winds that sweep onshore 80 kilometers to the west.

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