Grand Ethiopian Renaissance Dam production of less than 3 percent. The Grand Ethiopian Renaissance Dam could also lead to a permanent lowering of the water level in Lake Nasser, if floods are stored instead in Ethiopia. This would reduce the current evaporation of more than 10 billion cubic meter per year, but it would also reduce the ability of the Aswan High Dam to produce hydropower to the tune of a 100 MW loss of generating capacity for a 3 m reduction of the water level. However, the increased storage in Ethiopia can provide a greater buffer to shortages in Sudan and Egypt during
Aswan the summer solstice, a vertical staff cast no shadow. They noted that the sun's disc was reflected in a well at noon. This statement is only approximately correct; at the summer solstice, the shadow was only of the staff, and so could scarcely be discerned, and the northern limb of the Sun's disc would be nearly vertical. However, Eratosthenes used this information together with measurements of the shadow length on the solstice at Alexandria to perform the first known calculation of the circumference of the Earth. The Nile is nearly wide above Aswan. From this frontier town to the northern