The surface wind circulation over a complex terrain of central Spitsbergen

The aim of the study is to 1) compare surface wind measurements and reanalysed low-level geostrophic winds in the period of 2013-2016, and 2) evaluate a role of topography on spatiotemporal variability of winds within a fjord. For studying near-surface wind characteristics in central Spitsbergen (Billefjorden area), we chose three sites differing in terrain elevation and local surface properties: Petuniabukta terrace (15 m a.s.l.), Mimerbukta terrace (20 a.s.l.), and the top of Mumien Peak (773 m a.s.l.). Patterns of atmospheric circulation were identified using 1000-, 925- and 850-hPa geopotential heights and geostrophic winds based on the ERA5 reanalysis data provided by the ECMWF. Our results indicate that a large-scale flow was often modified by channelling and drainage effects accompanied by an increase in wind speed and wind direction frequency at the coastal sites. On the other hand, the near-surface wind at the top of the Mumien Peak was most similar to the geostrophic wind, irrespective of the circulation type.