On Wind Tides and Longshore Currents over the Continental Shelf Due to Winds Blowing at an Angle to the Coast

摘要

This paper begins with the usual equations of hydrodynamical motion in two dimensions. Certain assumptions are then made which lead to a direct analytical solution. One of the assumptions made is that the net transport shoreward is insignificant compared with the longshore transport, and in effect the net transport shoreward becomes zero under steady state conditions. Other assumptions made are that the rate of precipitation impact is negligible, the water surface slope parallel to the coastline is negligible, and that the higher order differentials along the coastline are much smaller than the corresponding counterparts directed perpendicular to the coastline. Finally, it is assumed that the bottom friction factor to be used with the longshore current can be approximated by use of n in Manning's equation. The special case of a continental shelf, bottom of constant slope, is treated in detail, although it is shown that the same principles can be applied to composite bottom profile, representing a bottom of variable slope.