Editing Nile (section)

=== Blue Nile ===
{{main|Blue Nile}}
[[File:ET Bahir Dar asv2018-02 img17 Tis Issat.jpg|thumb|left|The [[Blue Nile Falls]] fed by [[Lake Tana]] near the city of [[Bahir Dar]], Ethiopia]]
[[File:ISS036-E-011050.jpg|thumb|Annotated view of the Nile and Red Sea, with a dust storm<ref>{{Cite web |url=https://earthobservatory.nasa.gov/images/81566/egyptian-dust-plume-red-sea |archive-url=https://web.archive.org/web/20140222100350/http://earthobservatory.nasa.gov/IOTD/view.php?id=81566 |url-status=dead |title=Egyptian Dust Plume, Red Sea |date=8 July 2013 |archive-date=22 February 2014 |website=earthobservatory.nasa.gov }}</ref>]]
The Blue Nile ({{langx|am|ዓባይ}}, ''ʿĀbay''<ref>[[United States Board on Geographic Names|BGN]]/[[Permanent Committee on Geographical Names for British Official Use|PCGN]]. "[http://earth-info.nga.mil/gns/html/romanization.html Romanization System for Amharic] {{webarchive |url=https://web.archive.org/web/20130213212545/http://earth-info.nga.mil/gns/html/romanization.html |date=13 February 2013 }}". 1967. Hosted at the [[National Geospatial-Intelligence Agency]], 2013. Accessed 28 February 2014.</ref><ref>See also: [[BGN/PCGN romanization|{{sc|BGN/PCGN}} romanization]].</ref>) springs from Lake Tana in the Ethiopian Highlands. The Blue Nile flows about 1,400 kilometres to Khartoum, where the Blue Nile and White Nile join to form the Nile.<ref>{{Cite encyclopedia |title=Blue Nile River {{!}} river, Africa |encyclopedia=Encyclopedia Britannica |url=https://www.britannica.com/place/Blue-Nile-River |access-date=31 July 2017 |archive-url=https://web.archive.org/web/20170801185437/https://www.britannica.com/place/Blue-Nile-River |archive-date=1 August 2017 |url-status=live }}</ref> Ninety percent of the water and ninety-six percent of the transported sediment carried by the Nile<ref>Marshall et al.,{{Cite web |title=Late Pleistocene and Holocene environmental and climatic change from Lake Tana, source of the Blue Nile |url=http://www.holivar2006.org/abstracts/pdf/T1-026.pdf |url-status=dead |archive-url=https://web.archive.org/web/20060928124412/http://www.holivar2006.org/abstracts/pdf/T1-026.pdf |archive-date=28 September 2006 |access-date=30 September 2006 }}</ref> come from the Atbarah and Blue Nile,{{fix|text=1,922 out of 2,633 m3/s = 73%, so somewhere our numbers are off}} both of which originate in Ethiopia, with fifty-nine percent of the water coming from the Blue Nile. The erosion and transportation of silt only occurs during the Ethiopian [[Wet season|rainy season]] when rainfall is especially high in the [[Ethiopian Highlands]]; the rest of the year, the great rivers draining Ethiopia into the Nile have a weaker flow. In harsh and arid seasons and droughts, the Blue Nile dries out completely.<ref>{{Cite web |date=26 April 2013 |title=Two Niles Meet : Image of the Day |url=https://earthobservatory.nasa.gov/IOTD/view.php?id=81186 |url-status=live |archive-url=https://web.archive.org/web/20170415093951/https://earthobservatory.nasa.gov/IOTD/view.php?id=81186 |archive-date=15 April 2017 |access-date=31 July 2017 |website=earthobservatory.nasa.gov }}</ref>

The flow of the Blue Nile varies considerably over its yearly cycle and is the main contribution to the large natural variation of the Nile flow. During the dry season the natural discharge of the Blue Nile can be as low as {{cvt|113|m3/s|sp=us}}, although upstream dams regulate the flow of the river. During the wet season, the peak flow of the Blue Nile often exceeds {{cvt|5663|m3/s|sp=us}} in late August (a difference of a factor of 50).

Before the placement of dams on the river the yearly discharge varied by a factor of 15 at Aswan. Peak flows of over {{cvt|8212|m3/s|sp=us}} occurred during late August and early September, and minimum flows of about {{cvt|552|m3/s|sp=us}} occurred during late April and early May.