Dealing with challenges of altimetry-based surface water height derivation over boreal catchments : case study of Mackenzie river

• Main Author: Liu, Jiaxin
• Format: Bachelor Thesis
• Language: English
• Published: 2022
• Subjects: 550; Canada; Mackenzie River; Mackenzie river
• Online Access: https://doi.org/10.18419/opus-12116; http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-ds-121337; http://elib.uni-stuttgart.de/handle/11682/12133

The Earth is a watery place, which fills the oceans, rivers, and lakes. Approximately 71% of the Earth’s surface is water-covered. Measurements of surface water level in oceans, lakes, rivers and coastal waters are important for a variety of reasons. In the short term, this can, for example, help to alert to dangerous water level so that actions can be taken in advance, while in the long term, monitoring water levels can provide even greater insight into patterns of water dispersal in the area, and measure, for example, the effects of global warming. Satellite altimetry, which was originally designed for oceanography in the 1970s, has revolutionized our knowledge of the marine gravity field, of the dynamics of the oceans and even ofland hydrology. It is a space measurement technique that uses artificial satellites to measure the altitude from the satellite to the Earth’s surface. Due to its high resolution, global coverage and short revisit time, it is playing an increasingly important role in measurements of water level. For some years, this technology has also been used to retrieve water levels from rivers, lakes, and any inland water body as well. However, compared with the wide seas, measurements of inland water bodies involve many challenges. In this paper, we will take the Mackenzie River in northern Canada as a research object and process the data through the Matlab-based program Atlbundle+ to study the potential of inland altimetry, the problems it faces and the possible ways to find the solution. In general, there are two perspectives that will be considered: Firstly, how we can accurately remove outliers in the measurements, and secondly, how to improve the altimetry-driven water level time series by improving the retracking methods. Finally, based on the results and the procedure, a systematic analysis of the inland altimetry can be carried out.