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The infra-red radiation thermometry done over the coastal waters off Richards Bay is described. A model concerning the local current behaviour is derived from these results as well as measurements from a research vessel. It is postulated that the atmospheric forcing of the Agulhas Current at nodal points along the South African East Coast has direct bearing on the creation of inshore turbulence and reversals regularly experienced along this coast.

The linearized hydrodynamic equations for storm surges are solved in analytic form for a very simple model basin and an arbitrary field of wind and pressure to show that a solution can be obtained as an integral of the product of the atmospheric forcing function and an influence function whose value tends to zero with increasing time lags. In practical cases this solution can be computed as a weighted sum of the meteorological observations during a short period before the storm surge observation. A finite difference scheme for a slightly more general basin is then developed and the solution given formally in terms of a polynomial involving both vectors and matrices. It is shown that this solution is equivalent to the analytic solution and that both are equivalent to a linear function of the meteorological measurements of wind and pressure which must be used to obtain a description of any actual forcing function for storm surges. The technique can be generalized to provide the solution for basins ...