The wind set-down hypothesis (Exodus 13)

The crossing of the Red Sea is a remarkable Old Testament miracle. The Biblical narrative relies on the water’s having been shallow enough that a powerful east wind blowing all night could have pushed it back, yet deep enough that pursuing chariot forces would have drowned when the waters ultimately closed in. The Bible specifically records that God used nature (the east wind) to effect this miracle, and any credible explanation must factor in that natural phenomenon.

A shallow marsh (as some have proposed) would not have sufficed, because even if one night of wind could have dried it out so that chariots would have become mired in the mud, no one would have drowned in such shallow water.

Physicist Colin Humphreys suggest that a phenomenon  known as “wind set-down” satisfies the Biblical account. This occurs when a strong, steady wind blows along a lengthy body of water that is fairly long relative to its width. The water level drops significantly on the windward side, while a wall of water is pushed up on the lee side. If wind continues to blow across the length of the sea, the drag of the water causes a gap to open up and expose the sea floor. This phenomenon is observed today in various bodies of water around the world when wind conditions and the layout of the water are right.

Among the candidates for the possible location of the Red Sea, only the Gulf og\f Aqaba could have allowed such wind set-down to occur, since the body of water needed to be long and narrow relative to its length in order for this phenomenon to  have taken place. The east wind the Bible describes could have been either a northeast or a southeast wind (ancient Hebrew has no specific word for either). Since the Gulf of Aqaba is oriented northeast to southwest, a northeast wind would have pushed the waters down along the Aqaba.

In contrast, the lakes north of the Gulf of Suez are too small for such a large wind set-down of water, and the Gulf of Suez is oriented in the wrong direction. A northwest wind would have been required for a wind set-down in the Suez.