Temperature monitoring along the Rhine River based on airborne thermal infrared remote sensing: estimation of in situ water temperatures and inflow detection compared to artificial satellite data

摘要

Water temperature is an important parameter of water quality. It influences the survival and growth of animal and plant species in river ecosystems. Current in situ measurements do not allow for the spatial coverage that is necessary for continuous monitoring. Hence, the ability of remote sensing temperatures from aerial and artificial satellite datasets to accurately identify and investigate water temperature and inflows is evaluated for a case study of the Upper and Middle Rhine River. Water surface temperatures acquired by an aerial survey and the results of two correction methods were evaluated: the difference to in situ measurements could be reduced to 0.04 +/- 0.21 degrees C with a calibration based on in situ measurements and to 0.14 +/- 0.33 degrees C based on atmospheric parameters modeled with MODTRAN (R) 5.3.2. Inflows and mixing processes of water bodies with differing temperatures could be identified successfully with the change point analysis method and based on the standard deviation of the distributed longitudinal profile even for smaller dischargers. With the artificial satellite datasets, the ability to detect inflows decreases mainly with the noise of the dataset, also leading to a higher number of false positive change points. (C) The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License.