Editing Red Sea (section)

== Oceanography ==
[[File:ISS036-E-011050.jpg|thumb|upright=1.3|Annotated view of the Nile and Red Sea, with a dust storm, viewed from the [[International Space Station]]<ref>{{Cite web |date=8 July 2013 |title=Egyptian Dust Plume, Red Sea |url=http://earthobservatory.nasa.gov/IOTD/view.php?id=81566 |url-status=live |archive-url=https://web.archive.org/web/20140222100350/http://earthobservatory.nasa.gov/IOTD/view.php?id=81566 |archive-date=22 February 2014 |access-date=4 February 2014 |website=earthobservatory.nasa.gov}}</ref>]]
[[File:Day Pass down the Red Sea.ogv|thumb|upright=1.35|This video over the south-eastern [[Mediterranean Sea]] and down the coastline of the Red Sea was taken by the crew of Expedition 29 on board the International Space Station.]]
The Red Sea is between arid land, [[desert]] and [[semi-desert]]. Reef systems are better developed along the Red Sea mainly because of its greater depths and an efficient water circulation pattern. The Red Sea water mass-exchanges its water with the [[Arabian Sea]], [[Indian Ocean]] via the [[Gulf of Aden]]. These physical factors reduce the effect of high salinity caused by evaporation in the north and relatively hot water in the south.<ref>{{Cite journal |last1=Sofianos |first1=Sarantis S. |last2=Johns |first2=William E. |date=2002 |title=An Oceanic General Circulation Model (OGCM) investigation of the Red Sea circulation, 1. Exchange between the Red Sea and the Indian Ocean |journal=Journal of Geophysical Research: Oceans |language=en |volume=107 |issue=C11 |page=3196 |bibcode=2002JGRC..107.3196S |doi=10.1029/2001JC001184 |doi-access=free}}</ref>

The [[climate]] of the Red Sea is the result of two [[monsoon]] seasons: a northeasterly monsoon and a southwesterly monsoon. Monsoon winds occur because of differential heating between the land and the sea. Very high surface temperatures and high salinities make this one of the warmest and saltiest bodies of seawater in the world. The average surface water temperature of the Red Sea during the summer is about {{cvt|26|C|F|0}} in the north and {{cvt|30|C|F|0|}} in the south, with only about {{cvt|2|C-change}} variation during the winter months. The overall average water temperature is {{cvt|22|C|F|0|}}. Temperature and visibility remain good to around {{cvt|200|m|ft}}. The sea is known for its strong winds and unpredictable local currents.{{citation needed|date=February 2019}}

The [[rainfall]] over the Red Sea and its coasts is extremely low, averaging {{cvt|60|mm|in|2}} per year. The rain is mostly short showers, often with thunderstorms and occasionally with dust [[storm]]s. The scarcity of rainfall and no major source of fresh water to the Red Sea result in excess evaporation as high as {{cvt|2050|mm|in|0}} per year and high salinity with minimal seasonal variation. A recent{{When|date=June 2023}} underwater expedition to the Red Sea offshore from [[Sudan]] and [[Eritrea]]<ref>[[BBC 2]] television program "''Oceans 3/8 The Red Sea''", 8 pm–9 pm Wednesday 26 November 2008</ref>{{Verify source|date=June 2023}} found surface water temperatures {{cvt|28|C|F|0}} in winter and up to {{cvt|34|C|F|0}} in the summer, but despite that extreme heat, the coral was healthy with much fish life with very little sign of [[coral bleaching]], with only 9% infected by ''[[Thalassomonas loyana]]'', the 'white plague' agent. [[Favia|''Favia favus'']] coral there harbours a virus, BA3, which kills ''T. loyana''.<ref>{{Cite web |title=Virus power harnessed to protect Red Sea coral |url=https://www.newscientist.com/article/mg21528725-700-virus-power-harnessed-to-protect-red-sea-coral/ |url-status=live |archive-url=https://web.archive.org/web/20150423092252/http://www.newscientist.com/article/mg21528725.700-virus-power-harnessed-to-protect-red-sea-coral.html |archive-date=23 April 2015 |access-date=4 June 2023 |website=New Scientist |language=en-US}}</ref>
Scientists are investigating the unique properties of these coral and their [[commensal]] [[algae]] to see if they can be used to salvage bleached coral elsewhere.<ref>{{Cite web |last=Fitzgerald |first=Sunny |date=8 April 2020 |title=The super-corals of the Red Sea |url=https://www.bbc.com/future/article/20200408-the-middle-eastern-corals-that-could-survive-climate-change |url-status=live |archive-url=https://web.archive.org/web/20220507075625/https://www.bbc.com/future/article/20200408-the-middle-eastern-corals-that-could-survive-climate-change |archive-date=7 May 2022 |access-date=24 May 2022 |publisher=[[BBC Future]]}}</ref>

=== Salinity ===
The Red Sea is one of the saltiest bodies of water in the world, owing to high evaporation and low precipitation; no significant rivers or streams drain into the sea, and its southern connection to the [[Gulf of Aden]], an arm of the Indian Ocean, is narrow.<ref>{{Cite book |last=Por |first=F. D. |url=https://books.google.com/books?id=syn0CAAAQBAJ&q=salinity+of+the+Red+Sea+is+greater+than+the+world+average,&pg=PA65 |title=The Legacy of Tethys: An Aquatic Biogeography of the Levant |date=6 December 2012 |publisher=Springer Science & Business Media |isbn=978-94-009-0937-3 |language=en |access-date=19 November 2020 |archive-url=https://web.archive.org/web/20230210065003/https://books.google.com/books?id=syn0CAAAQBAJ&q=salinity+of+the+Red+Sea+is+greater+than+the+world+average,&pg=PA65 |archive-date=10 February 2023 |url-status=live}}</ref> Its [[salinity]] ranges from between ~36&nbsp;[[per mil|‰]] in the southern part and 41&nbsp;‰ in the northern part around the [[Gulf of Suez]], with an average of 40&nbsp;‰. (Average salinity for the world's [[seawater]] is ~35&nbsp;‰ on the Practical Salinity Scale, or PSU; that translates to 3.5% of actual dissolved salts).<ref>{{Cite book |last=Hanauer |first=Eric |url=https://books.google.com/books?id=uh6mcZC8yWIC&q=salinity+of+the+Red+Sea+is+greater+than+the+world+average,&pg=PA67 |title=The Egyptian Red Sea: A Diver's Guide |date=1988 |publisher=Aqua Quest Publications, Inc. |isbn=978-0-922769-04-9 |language=en |access-date=19 November 2020 |archive-url=https://web.archive.org/web/20230210065001/https://books.google.com/books?id=uh6mcZC8yWIC&q=salinity+of+the+Red+Sea+is+greater+than+the+world+average,&pg=PA67 |archive-date=10 February 2023 |url-status=live}}</ref>

=== Tidal range ===
In general, tide ranges between {{cvt|0.6|m|ft|1}} in the north, near the mouth of the Gulf of Suez and {{cvt|0.9|m|ft|1}} in the south near the Gulf of Aden, but it fluctuates between {{cvt|0.20|m|ft|2}} and {{cvt|0.30|m|ft|2}} away from the nodal point. The central Red Sea (Jeddah area) is therefore almost tideless, and as such the annual water level changes are more significant. Because of the small tidal range the water during high tide inundates the coastal [[sabkha]]s as a thin sheet of water up to a few hundred metres rather than flooding the [[sabkha]]s through a network of channels. However, south of Jeddah in the [[Shoiaba]] area, the water from the lagoon may cover the adjoining sabkhas as far as {{cvt|3|km|mi|0}}, whereas north of [[Jeddah]] in the [[Al-Kharrar]] area the sabkhas are covered by a thin sheet of water as far as {{cvt|2|km|mi|1}}. The prevailing north and northeast winds influence the movement of water in the coastal inlets to the adjacent sabkhas, especially during storms. Winter mean sea level is {{cvt|0.5|m|ft|1}} higher than in summer. Tidal velocities passing through constrictions caused by reefs, sand bars and low islands commonly exceed {{cvt|1–2|m/s|0}}. Coral reefs in the Red Sea are near Egypt, Eritrea, Israel, Saudi Arabia, and Sudan.<ref>{{Cite web |title=Coral Reefs of the Gulf of Aqaba and the Red Sea in the Kingdom of Saudi Arabia |url=https://whc.unesco.org/en/tentativelists/6701/ |access-date=18 June 2024 |website=UNESCO World Heritage Centre |language=en}}</ref>

=== Current ===
Detailed information regarding current data is lacking, partially because the currents are weak and both spatially and temporally variable. The variation of temporal and spatial currents is as low as {{cvt|0.5|m|ft|1}}{{clarify|what does this mean?|date=October 2021}} and are governed all by wind. During the summer, northwesterly winds drive surface water south for about four months at a velocity of {{cvt|15–20|cm/s|0}}, whereas in winter the flow is reversed resulting in the inflow of water from the Gulf of Aden into the Red Sea. The net value of the latter predominates, resulting in an overall drift to the north end of the Red Sea. Generally, the velocity of the tidal current is {{cvt|50–60|cm/s|0}} with a maximum of {{cvt|1|m/s|ft/s|1}} at the mouth of the al-Kharrar Lagoon. However, the range of the north-northeast current along the Saudi coast is {{cvt|8–29|cm/s|0}}.{{citation needed|date=February 2019}}

=== Wind regime ===
The north part of the Red Sea is dominated by persistent north-west [[winds]], with speeds ranging between {{cvt|7|km/h|mph|1}} and {{cvt|12|km/h|mph|1}}. The rest of the Red Sea and the [[Gulf of Aden]] are subjected to regular and seasonally reversible winds. The wind [[regime]] is characterized by seasonal and regional variations in [[speed]] and [[direction (geometry, geography)|direction]] with average speed generally increasing northward.<ref>{{Cite journal |last=Patzert |first=William C. |date=1 February 1974 |title=Wind-induced reversal in Red Sea circulation |url=https://dx.doi.org/10.1016/0011-7471%2874%2990068-0 |journal=Deep Sea Research and Oceanographic Abstracts |language=en |volume=21 |issue=2 |pages=109–121 |doi=10.1016/0011-7471(74)90068-0 |bibcode=1974DSRA...21..109P |issn=0011-7471}}</ref>

Wind is the driving force in the Red Sea to transport material as suspension or as bedload. Wind-induced currents play an important role in the Red Sea in resuspending bottom sediments and transferring materials from sites of dumping to sites of burial in quiescent environment of deposition. Wind-generated current [[measurement]] is therefore important in order to determine the sediment dispersal pattern and its role in the erosion and accretion of the coastal rock exposure and the submerged coral beds.<ref>{{Cite journal |last=Morcos |first=S. A. |date=1970 |title=Physical and chemical oceanography of the Red Sea |journal=Oceanography and Marine Biology: An Annual Review}}</ref>