The exact date is not crucial to our study. We set our study during Egypt's New Kingdom period, with a nominal date of 1250 BC. Consequently, an easterly wind there will not produce a dry region with water remaining on both sides. The Gulf of Suez, which was the study area in Nof & Paldor and Voltzinger & Androsov, is oriented primarily North-South. This choice of direction restricts the hydrodynamic possibilities to those bodies of water near Sinai that have a long East-West extent. Under this easterly wind forcing we investigate the possible separation of a body of water, with the presence of water remaining on both sides of a dry passage. In this paper we retain the easterly wind direction described by Tulloch, noting that the primary axis of Lake Manzala is oriented East-West. Tulloch: It was “packed up” to the north-west. Tulloch: It is only about 5 feet or 6 feet. Rooke: I should like to ask the present depth of Lake Menzahleh near Port Said? When noticing this extraordinary dynamical effect of wind on shallow water, it suddenly flashed across my mind that I was witnessing a similar event to what had taken place between three and four thousand years ago, at the time of the passage of the so-called Red Sea by the Israelites. Next morning on going out I found that Lake Menzaleh, which is situated on the west side of the Canal, had totally disappeared, the effect of the high wind on the shallow water having actually driven it away beyond the horizon, and the natives were walking about on the mud where the day before the fishing-boats, now aground, had been floating. One day, when so employed between Port Said and Kantarah, a gale of wind from the eastward set in and became so strong that I had to cease work. Tulloch of the British Army reported this event happening on Lake Manzala in January or February 1882: Scientific literature from the 19 th century contains a description of a wind setdown event that occurred in the eastern Nile delta. We consider a site at the northern end of the isthmus that exhibits similar interaction between wind and water. It is important to investigate these other possibilities. Since the isthmus of Suez is a low-lying area that in ancient times contained several shallow bodies of water and interconnecting river channels, there are additional sites that are interesting from a hydrodynamic perspective. They noted that the dividing ridge between the Suez basin and the rest of the Gulf of Suez significantly increases the time to reach a steady-state solution. Voltzinger & Androsov calculated an exposure time of 4 hours for the reef, using a wind speed that ramps up from 0 m/s and blows at 33 m/s for 12 hours. They suggested that wind blowing initially from the Northeast gradually changed direction to blow from the Northwest, becoming aligned with the axis of the Gulf. The modern reef at approximately 10 m deep was raised to a uniform depth of 3 m below sea level. Voltzinger & Androsov used a 3-dimensional (3-D) model to simulate the reef at 29.88° N in the Gulf of Suez. The wind blows from the Northwest, as studied by Nof and Paldor and Voltzinger and Androsov. Point A on the raised portion of the reef is used to compare with the notch (see Figures 5 and and6). Here we use a single notch to demonstrate how variations in the reef depth may delay the crossing. The reef at 29.88° North latitude is not of uniform depth today, but contains several deeper “notches” that were present before the Suez Canal was built. The proposed reef is at 29.88° N it extends about 10 km under the Gulf of Suez from a point 3 km Southeast of Adabiya across to Uyun Musa on the eastern shore (see Figure 1 for an idealized map of Suez). They suggested that the water receded and an underwater reef emerged from the sea when the wind setdown occurred. They used a wind blowing from the Northwest, aligned with the primary axis of the Gulf of Suez. Nof & Paldor, found analytical solutions to the differential equations of a 1-dimensional (1-D) model that govern the water's free surface under wind stress forcing. They suggested that a large number of people (the Israelites) could possibly “cross the sea” on such a dry passage. Previous researchers analyzed a more interesting phenomenon: the formation of a land bridge extending from one original shoreline to another, with water remaining on both sides of the bridge. Tidal ebbs can cause water to recede from the original shoreline and expose the bottom of the sea, and it is easy to imagine wind stress causing similar behavior.
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