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Atmospheric Science
Atmospheric Science

Photo: Earth Science and Remote Sensing Unit, NASA Johnson Space Center

Improving cloud coverage observations in the Arctic

9 February 2026

Leonie Nellesen after her MSc defense

Photo: UHH / Bühler

Leonie Nellesen successfully defended her Master’s thesis. Congrats, Leonie! Her work focused on improving cloud cover observations in the Arctic by using all-sky camera images from Svalbard and developing a new machine-learning algorithm, helping to fill crucial data gaps during the polar night. She then put these new observations to the test by evaluating the AROME-Arctic weather model, showing it performs well overall but struggles during cold air outbreaks.

Thesis: Nellesen, L. (2026), Developing a new cloud cover product for the evaluation of an operational weather prediction model in the Arctic (PDF)

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