Reconstruction of Lake Level Changes of Groundwater-Fed Lakes in Northeastern Germany Using RapidEye Time Series

Abstract

Groundwater-fed lakes in northeastern Germany are characterized by significant lake level changes, but for only a few lakes are in situ water level measurements available. In this study, we test the potential of RapidEye satellite images for indirectly reconstructing lake level changes. The lake levels are derived by intersecting water-land borders with a high-resolution digital elevation model (DEM). Based on Lake Fürstenseer (LF), we define requirements and limitations of the method. Water-land borders were extracted automatically from the 37 RapidEye images available for the period between 2009 and 2014. Otsu's threshold was used for the NIR band and for the normalized difference water index (NDWI). The results were validated with in situ gauging, contour lines from the DEM, and in situ Differential Global Positioning System (DGPS) measurements of the shoreline. Using an ideal shoreline subset, the lake levels could be reconstructed with decimeter accuracy using the NIR water-land border, but the levels were systematically underestimated by 0-20 cm. The accuracy of the reconstructed lake level retrieval strongly depends on the precision of the water-land border retrieval, on the accuracy of the DEM, and on the lake level itself. A clear shift of the water-land border with increasing lake level is also essential for the unambiguous reconstruction of different levels. This shift needs to be several times larger than the pixel size. The biggest challenges OPEN ACCESSWater 2015, 7 4176 for lake level reconstruction are the presence of vegetation at the shorelines, the quality of the topographic data in the underwater area, the slope of the shoreline, and shadows in combination with low solar angles.

Application of Low-Cost Fixed-Wing UAV for Inland Lakes Shoreline Investigation

“…In most reservoirs, bathymetry can be measured with instruments such as sonar, singlebeam echo sounder (SBES) or multi-beam systems (MBES) and bathymetric airborne LiDAR (International Hydrographic Organization 2005). Additional analysis of the adjacent topography requires remote sensing products like aerial photography, satellite images or radar imagery (Heine et al 2015;Szostak et al 2014;Szulwic et al 2015).…”

An investigation of water level fluctuations in Polish lakes in various phases of the winter North Atlantic Oscillation

“…The area of north-east Central Europe is distinguished by a high number of lakes (Heine et al 2015). According to Choiński (2006), the territory of Poland includes more than 7,000 natural lakes with an area of 1 ha or more.…”

Using Uav to Detect Shoreline Changes: Case Study – Pohranov Pond, Czech Republic

“…Data are processed by many different methods according to their content and expected results (e.g. Heine, 2015;Li et al, 2013;Nath and Deb, 2010).…”

“…Some studies are particularly focused on water bodies (e.g. Gallop et al, 2015;Pechanec et al, 2015;Heine et al, 2015).…”