These images show the dramatic urban growth within the Nile River Delta and the expansion of agriculture into adjoining desert areas. The Nile is the world's longest river at 4,160 miles. It flows south to north, bringing fresh, nutrient-rich water to Egypt.
In these images, red indicates vegetation. The contrast is clear between the lush vegetation of irrigated fields and the white or tan barren desert.
Cairo, shown as the large gray expanse in these images, increased in population from 1.5 million to 6 million between 1947 and 1986. Its 2009 population was estimated to be almost 11 million. Urban expansion is also noticeable in the other parts of the delta, as indicated by the increased size of the smaller urban areas surrounding Cairo.
So, where are the Great Pyramids? They are visible, but Landsat's 30-meter resolution is not designed to show that much detail.
The area of vegetation just outside the delta northwest of Cairo is new agricultural development, with some of the crops irrigated through center-pivot irrigation. The most common crops grown are cotton, rice, corn, potatoes, oranges, and wheat. Although areas at a distance from the Nile often are not able to be irrigated, land that does support crops produces high yields and is harvested two or three times in many years.
Food shortages have been documented for thousands of years in Egypt, and they can still cause problems. As the Egyptian population grows, producing enough food has become more difficult, so the government subsidizes food to make comfortable life possible. One staple food highly subsidized in Egypt is bread. The "bread riots" in 1977 and 2008 were the result of a reduction in those subsidies.
Despite government regulation that keeps the production of non-food crops like cotton low, Egypt still imports much of its food, especially wheat. This can increase the price of food even higher.
Egypt's agrarian society is also threatened by southern countries (which are upstream of the Nile River from Egypt). Ethiopia announced plans to build a hydropower dam in May 2011. The dam would reduce the amount of water making its way to Egypt, making growing crops more difficult and food even more expensive.