On remote sensing of vertical shear of ocean surface currents by means of a single-frequency VHF radar

We propose and test experimentally a new way of probing vertical shear of o cean surface currents by means of a single frequency VHF radar. The key ide a is to use additional information provided by the so called secondary peak s in radar echo spectra which appear due to nonlinearity. Results of the fi eld experiment carried out in the Rhone's delta show that the new method do es enable one to probe the vertical shear with a reasonable accuracy and ha s potential for further development.