Case studies of the wind field around Ny-Ålesund, Svalbard, using unmanned aircraft

• Published in: Polar Research
• Main Authors: Martin Schön, Irene Suomi, Barbara Altstädter, Bram van Kesteren, Kjell zum Berge, Andreas Platis, Birgit Wehner, Astrid Lampert, Jens Bange
• Format: Article in Journal/Newspaper
• Language: English
• Published: Norwegian Polar Institute 2022
• Subjects: microscale meteorology; boundary layer; wind measurement; aircraft measurement; kongsfjorden; arctic fjord; geo; envir; Arctic; Ny-Ålesund; Svalbard; Kongsfjord*; Kongsfjorden; Ny Ålesund; Polar Research
• Online Access: https://doi.org/10.33265/polar.v41.7884; https://doaj.org/article/bde9f253b6444ad9a7d72df0fdb8affb

The wind field in Arctic fjords is strongly influenced by glaciers, local orography and the interaction between sea and land. Ny-Ålesund, an important location for atmospheric research in the Arctic, is located in Kongsfjorden, a fjord with a complex local wind field that influences measurements in Ny-Ålesund. Using wind measurements from UAS (unmanned aircraft systems), ground measurements, radiosonde and reanalysis data, characteristic processes that determine the wind field around Ny-Ålesund are identified and analysed. UAS measurements and ground measurements show, as did previous studies, a south-east flow along Kongsfjorden, dominating the wind conditions in Ny-Ålesund. The wind measured by the UAS in a valley 1 km west of Ny-Ålesund differs from the wind measured at the ground in Ny-Ålesund. In this valley, we identify a small-scale catabatic flow from the south to south-west as the cause for this difference. Case studies show a backing (counterclockwise rotation with increasing altitude) of the wind direction close to the ground. A katabatic flow is measured near the ground, with a horizontal wind speed up to 5 m s-1. Both the larger-scale south-east flow along the fjord and the local katabatic flows lead to a highly variable wind field, so ground measurements and weather models alone give an incomplete picture. The comparison of UAS measurements, ground measurements and weather conditions analysis using a synoptic model is used to show that the effects measured in the case studies play a role in the Ny-Ålesund wind field in spring.