Sunday, October 20, 2019
The Nile River and Nile Delta in Egypt
The Nile River and Nile Delta in Egypt The Nile River in Egypt is among the longest rivers in the world, running for a length of 6,690 kilometers (4,150 miles), and it drains an area of roughly 2.9 million square kilometers, about 1.1Ã million square miles. No other region in our world is so dependent on a single water system, especially as it is located in one of our worlds most extensive and severe deserts. More than 90% of the population of Egypt today lives adjacent to and relies directly on the Nile and its delta. Because of ancient Egypts dependence on the Nile, the rivers paleo-climatic history, particularly the changes in the hydro-climate, helped shape the growth of dynastic Egypt and led to the decline of numerous complex societies. Physical Attributes There are three tributaries to the Nile, feeding into the main channel which flows generally northward to empty into the Mediterranean Sea. The Blue and the White Nile join together at Khartoum to create the main Nile channel, and the Atbara River joins the main Nile channel in northern Sudan. The Blue Niles source is Lake Tana; the White Nile is sourced at equatorial Lake Victoria, famously confirmed in the 1870s by David Livingston and Henry Morton Stanley. The Blue and Atbara rivers bring most of the sediment into the river channel and are fed by summer monsoon rains, while the White Nile drains the larger Central African Kenyan Plateau. The Nile Delta is roughly 500 km (310 mi) wide and 800 km (500 mi) long; the coastline as it meets the Mediterranean is 225 km (140 mi) long. The delta is made up mainly of alternating layers of silt and sand, laid down by the Nile over the past 10 thousand years or so. The elevation of the delta ranges from about 18 m (60 ft) above mean sea level at Cairo to around 1 m (3.3 ft) thick or less at the coast. Using the Nile in Antiquity The ancient Egyptians relied on the Nile as their source for reliable or at least predictable water supplies to allow their agricultural and then commercial settlements to develop. In ancient Egypt, the flooding of the Nile was predictable enough for the Egyptians to plan their yearly crops around it. The delta region flooded annually from June to September, as a result of monsoons in Ethiopia. A famine resulted when there was inadequate or surplus flooding. The ancient Egyptians learned partial control of the flood waters of the Nile by means of irrigation. They also wrote hymns to Hapy, the Nile flood god. In addition to being a source of water for their crops, the Nile River was a source of fish and waterfowl, and a major transportation artery linking all of the parts of Egypt, as well as linking Egypt to its neighbors. But the Nile does fluctuate from year to year. From one ancient period to the next, the course of the Nile, the amount of water in its channel, and the amount of silt deposited in the delta varied, bringing abundant harvest or devastating drought. This process continues. Technology and the Nile Egypt was first occupied by humans during the Paleolithic period, and they were undoubtedly affected by the Niles fluctuations. The earliest evidence for technological adaptations of the Nile occurred in the delta region at the end of the Predynastic Period, between about 4000 and 3100 B.C.E., when farmers began building canals. Other innovations include: Predynastic (1st Dynasty 3000Ã¢â¬â2686 B.C.E.)- Sluice gate construction allowed deliberate flooding and draining of farm fieldsOld Kingdom (3rd Dynasty 2667Ã¢â¬â2648 B.C.E.)- 2/3 of the delta was affected by irrigation worksOld Kingdom (3rdÃ¢â¬â8th Dynasties 2648Ã¢â¬â2160 B.C.E.)- Increasing aridification of the region leads to the progressively advanced technology including the building of artificial levees and enlarging and dredging of natural overflow channelsOld Kingdom (6thÃ¢â¬â8th Dynasties)- Despite the new technologies developed during the Old Kingdom, aridification increased such that there was a 30 year period in which flooding of the delta did not occur, contributing to the end of the Old Kingdom.New Kingdom (18th dynasty, 1550Ã¢â¬â1292 B.C.E.)- Shadoof technology (so-called Archimedes Screw invented long before Archimedes) first introduced, allowing farmers to plant several crops a yearPtolemaic period (332Ã¢â¬â30 B.C.E.)- Agricultural intensificatio n increased as population moved into the delta regionArab Conquest (1200Ã¢â¬â1203 C.E.)- Severe drought conditions led to famine and cannibalism as reported by the Arabic historian Abd al-Latif al-Baghdadi (1162Ã¢â¬â1231 C.E.) Ancient Descriptions of the Nile From Herodotus, Book II of The Histories: [F]or it was evident to me that the space between the aforesaid mountain-ranges, which lie above the city of Memphis, once was a gulf of the sea,... if it be permitted to compare small things with great; and small these are in comparison, for of the rivers which heaped up the soil in those regions none is worthy to be compared to volume with a single one of the mouths of the Nile, which has five mouths. Also from Herodotus, Book II: If then the stream of the Nile should turn aside into this Arabian gulf, what would hinder that gulf from being filled up with silt as the river continued to flow, at all events within a period of twenty thousand years? From Lucans Pharsalia: Egypt on the west Girt by the trackless Syrtes forces back By sevenfold stream the ocean; rich in glebe And gold and merchandise; and proud of Nile Asks for no rain from heaven. Sources: CastaÃ ±eda IS, Schouten S, Ptzold J, Lucassen F, Kasemann S, Kuhlmann H, and SchefuÃÅ¸ E. 2016. Hydroclimate variability in the Nile River Basin during the past 28,000 years. Earth and Planetary Science Letters 438:47-56.Krom MD, Stanley JD, Cliff RA, and Woodward JC. 2002. Nile River sediment fluctuations over the past 7000 yr and their key role in sapropel development. Geology 30(1):71-74.Santoro MM, Hassan FA, Wahab MA, Cerveny RS, and Robert C Balling J. 2015. An aggregated climate teleconnection index linked to historical Egyptian famines of the last thousand years. The Holocene 25(5):872-879.Stanley DJ. 1998. Nile Delta in its destruction phase. Journal of Coastal Research 14(3):794-825.