Spatial variations of the hummocks keel draft in the Laptev Sea area

The article investigates the morphometric features of the ice cover lower surface in the Laptev Sea area. The main attention is paid to the study of the hummocked formations’ keel draft and the spatial variability of this quantity. The data for the research were obtained during several ice seasons (from two to four) in the period 2014-2019 using upward-looking sonars, which were part of the submerged autonomous buoy stations (SABS). The stations were installed at five points in the Laptev Sea area. The data obtained from a series of observations of the ice cover draft allowed extracting information on the hummocked formations’ keel draft at separate points of the sea area. As a result, samples of values of the hummocks keel draft were formed for separate ice seasons for each of the five stations. Further, a statistical processing of the data obtained was performed. In particular, for each of the ice seasons we checked the homogeneity of the mean values and of the distribution of samples by stations. Also checked was the distribution matching. A comparative data analysis using methods of mathematical statistics made it possible to describe the spatial variability of the hummocked formations’ keel draft in the Laptev Sea area for separate ice seasons. The “key” points (stations) describing the spatial variability of the hummocked formations’ keel draft for all the ice seasons considered were determined according to the results of the analysis performed, which allows planning further ice draft research using SABS, if required (to determine the necessary number of stations and points of their installation).