OVERVIEW OF THE IMPROVEMENTS MADE ON THE EMPIRICAL DETERMINATION OF THE SEA STATE BIAS CORRECTION

It has long been known that the sea level measured by radar altimeters is lower than the true sea level because the backscattered power per unit area is greater for the wave troughs than for the wave crests. This effect is known as the electromagnetic bias. Other sea-state-related biases additionally affect the altimeter range measurements. They are generally combined with the electromagnetic bias to form the sea state bias (SSB). This total bias ranges from a few centimetres up to a few decimetres and is still one of the major sources of error in satellite altimetry. Its theoretical modelling and understanding remains an important challenge. Therefore, the SSB correction still largely relies on empirical models, calibrated on the altimeter dat