Updated bathymetric chart of the East Aral Sea

The Aral Sea is located in an arid region with much sand and salt deposits in the surrounding barren open land. Hence, significant displacements of sediments into the lakebed by the action of wind, water, gravity, or snow are likely. The bathymetry of the lake was last observed in the 1960s, and within the last half century, the structure of the lakebed has changed.
Based on satellite observations of the temporal changes of shoreline (Landsat optical remote sensing) and water level (multi-mission satellite altimetry) over more than one decade an updated bathymetric chart for the East Basin of the Aral Sea has been generated. During this time, the geometry of the shallow East Basin experienced strong fluctuations due to the occurrence of periods of drying and strong inflow. By the year 2014 the East Basin fell dry. The dynamic behavior of the basin allowed for estimating the lake's bathymetry from a series of satellite-based information.
The river mouth made its impression in the present East Aral Sea, because its shrinking led to the inflow of much sediment into the lake's interior. In addition, salt deposits along the shorelines increased the corresponding elevation, a phenomenon that is more pronounced in the reduced lakebed because of increased salinity.
It must be noted that height estimates from satellite altimetry were only possible down to a minimum elevation of 27 m above sea level due to a lack of reliable altimetry data over the largely reduced water surface. In order to construct a complete bathymetric chart of the lakebed of the East Aral Sea heights below 27 m were obtained solely from Landsat optical images following the SRB (Selected Region Boundary) approach as described by Singh et al. (2015).

咸海地处干旱区域，周边荒芜开阔地带遍布沙质与盐渍沉积物。受风力、水流、重力及积雪作用影响，沉积物大量涌入湖床的情况极易发生。该湖的水深地形（bathymetry）数据最后一次实测是在20世纪60年代，而在过去半个世纪里，湖床结构已发生显著变化。
基于十余年间的海岸线（陆地卫星（Landsat）光学遥感）与水位（多任务卫星测高（multi-mission satellite altimetry））时序变化卫星观测数据，研究人员生成了咸海东盆地的更新版水深地形图。在此期间，受间歇性干涸与强补给期的影响，浅滩东盆地的几何形态经历了剧烈波动。至2014年，东盆地彻底干涸。该盆地的动态变化特征，使得研究人员可通过一系列卫星观测信息估算该湖的水深地形。
现今咸海东盆地的形态受河口影响显著——流域萎缩导致大量沉积物涌入湖体内部。此外，沿岸盐渍沉积物抬升了岸线高程，这一现象在因盐度升高而大幅缩减的湖床中表现得更为突出。
需特别说明的是，由于大面积缩减的水域缺乏可靠的测高数据，卫星测高法仅能获取海拔27米以上区域的高程估算值。为构建完整的咸海东盆地湖床水深地形图，对于海拔27米以下区域的高程数据，研究人员仅依据辛格等人（2015年）提出的选定区域边界（Selected Region Boundary, SRB）方法，通过陆地卫星光学影像获取。