Adaptive re-traking of Jason-1 altimeter data for inland waters (on an example the Gorky reservoir on the Volga river

The problem of minimization of the errors in the water level retrieving for the Gorky reservoir from altimetry measurements can be resolved by re-tracking of Jason-1 satellite altimeter data. For justification of the optimal re-tracking algorithm the average impulse response of the statistically inhomogeneous surface were calculated theoretically for the model of the terrain in the vicinity of Gorky reservoir. The modeled waveforms are in good agreement with the Jason-1 ,2 waveforms for the same area. Comparing of the data with in situ measurements shows that re-tracking significantly improves measurements of the water level. General principles of re-tracking algorithms for complex areas (land, coastal zone, inland waters, etc) based on calculations of the waveforms taking into account statistical inhomogeneity of the reflecting surface adjusted to a certain geographic region, are discussed.