Water Level and SWH Variations in the Middle-Sized Lakes of Russia on the Base of Jason-1, 2 Satellite Measurements
Rybushkina, Galina; Troitskaya, Yuliya; Soustova, Irina
Institute of Applied Physics RAS, RUSSIAN FEDERATION
The problem of applicability of satellite altimetry data to inland waters is of interest, since these data are publicly available and can be widely used to determine the variations in water level and other hydrological parameters of large rivers, lakes, reservoirs, etc. The possibility of using the standard processing algorithm (Ocean-1) of Jason- 1,2 satellite altimetry data for inland waters and methods of data retracking (reprocessing) was discussed in [1,2] (see also references there), where a method of regional retracking based on constructing a theoretical model describing the formation of telemetric waveforms by reflection from the piecewise constant surface was proposed. The other methods of retracking (threshold retracking, -retracking, improved threshold retracking) were developed in [3-5]. The latest development in this field is PISTACH product , in which retracking bases on the formal classification of typical forms of telemetric waveforms in the coastal zones and inland water bodies.
In this contribution we investigate the efficiency of different retracking methods of Jason-1,2 satellite data for middle-sized lakes of Russia: Chany, Segozero, Hanko, Oneko, Beloye, water areas of which are intersected by the Jason-1,2 tracks. The comparison of water level variations, obtained by different retracking methods is made and the correlation coefficient with in situ observations is calculated.
The possibility of determination of significant wave height (SWH) in the lakes through a two-step adaptive retracking is also studied. Calculation of the parameter SWH for Gorky Reservoir from May 2010 to March 2012 showed the anomalously high values of SWH, derived from altimetry data . That means that the calibration of this SWH for inland waters is required. The calibration was made used the results of scientific expeditions to the ground truth Gorky reservoir in August-October 2011, during which the measured wave height, wind speed and air temperature by measuring equipment placed on the ocean pole Froude . Based on this calibration, we obtained the values of SWH for the lakes investigated in this contribution.
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