Jobs & Karriere

Remote sensing allows to determine water quality parameters such as concentration and type of phytoplankton, suspended particles and dissolved organic matter. The oceans are routinely monitored since decades using satellites, but the low spatial resolution of spaceborn ocean-colour sensors limits their usage at regional scales. Thus, observations in coastal regions and inland waters, where water quality is of direct relevance for all humans, are to date snapshots based on a few experimental satellite sensors, airborne campaigns, or direct sampling from ship. In the last years unmanned aerial vehicles (UAVs) with adequate payload and endurance for monitoring tasks became affordable. In this thesis, methods and instrumentation for octocopterbased water quality monitoring shall be developed. These should focus on inland and shallow waters and take advantage of the peculiarities of octocopters compared to airplanes like close distance to the water surface, hovering times of more than 10 minutes at one location, potential operation under clouds and at darkness.

• Selection and installation of instrumentation for spectral measurements of upwelling and downwelling radiation, capturing stereo images, illuminating a target at night, and collecting water samples. Review of commercial instruments, purchase, adaptation to an existing octocopter in collaboration with DLR staff
• Calibration of the instrumentation. Characterize the spectrometers and cameras radiometrically, spectrally and geometrically using the DLR facility CHB.
• Development of measurement protocols. Define conditions for octocopter operation, instrument settings, and type and extent of validation measurements
• Organisation of field campaigns. Collect data using the octocopter, and reference data for validation using shipborne instruments.
• Development of algorithms for data analysis, such as
  • Spectral characterization of water samples. Operationalize laboratory measurements of absorption.
  • Determination of concentrations of water constituents using spectrometer data. Adapt existing inverse modeling algorithms to the used spectrometers. Study the potential and limits of measurements at cloud cover and at night.
  • Determination of water depth using stereo images.
  • Quantification of fluorescence excited by LEDs of different wavelengths using spectrometer data. Analyze the potential of the octocopter instrumentation for fluorescence measurements at night.

Please note: Applicants must not be of German nationality. The position is a DLR-DAAD research fellowship. For further information please visit the DAAD-page.