Atmospheric Climatologies Over Isfjorden, Svalbard

The Isfjorden region at the west coast of Spitsbergen is the most easily accessible area in the Svalbard Archipelago, making it a perfect outdoor laboratory for Arctic research. Due to its location in the high Arctic together with its complex terrain, the climatic conditions vary substantially both in time and space. Based on a new high-resolution reanalysis, we present climatologies of five major atmospheric variables over the Isfjorden region during 2011-2021 with special focus on local effects. For example, we find that topographic channeling effects often lead to differences in near-surface wind speeds of several m s-1 over small horizontal distances. During winter, the fjord acts as a heat and moisture island, ultimately impacting the adjacent low-elevation land areas. These land-sea gradients reverse during summer. High mountain areas surrounding the fjord experience substantially different climatic conditions, with for example, seasonal precipitation doubling from sea level to approximately 700 m. The spatial variability over the Isfjorden region is in general found to be smaller than its temporal counterpart but larger than the diurnal cycle. Besides these findings, this study furthermore demonstrates the importance of high-resolution regional atmospheric reanalyses compared to global products for the characterization of the local micro-climate over Arctic fjords and the interaction with surrounding land areas.