Measured and Modeled Historical Precipitation Trends for Svalbard

Abstract

Precipitation plays an important role in the Arctic hydrological cycle, affecting different areas like the surface energy budget and the mass balance of glaciers. Thus, accurate measurements of precipitation are crucial for physical process studies, but gauge measurements in the Arctic are sparse and subject to relocations and several gauge issues. From Svalbard, we analyze precipitation trends at six weather stations for the last 50–100 years by combining different observation series and adjusting for inhomogeneities. For the past 50 years, the measured annual precipitation has increased by 30%–45%. However, precipitation measurements in the cold and windy climate are strongly influenced by gauge undercatch. Correcting for undercatch reduces the trend values by 10% points, since the fraction of solid precipitation has decreased and undercatch is larger for solid precipitation. Thus, precipitation corrected for undercatch should be used to study “true” precipitation trends in the Arctic. Precipitation over Svalbard has been modeled by downscaling reanalysis data to a spatial resolution of 1 km. In general, the modeled annual precipitation is higher (13%–175%) than the measured values and mainly higher than the precipitation corrected for undercatch. Although the model resolves orographic effects on a regional scale, the downscaling is not able to reproduce local orographic enhancement for onshore winds, nor local effects of rain shadow. The downscaled dataset explains approximately 60% of the interannual precipitation variability. The model-based trends during 1979–2018 are positive, but weaker (~4% decade−1) than the observed (~8% decade−1) trends.

Accelerating future mass loss of Svalbard glaciers from a multi-model ensemble

“…During 1971–2017, temperatures in Svalbard have risen by 3–5 ° C (Hanssen-Bauer and others, 2019), with fastest changes in northern and eastern Svalbard. At the same time, precipitation trends at weather stations in recent decades have not been significant or show moderate positive significant trends (Hanssen-Bauer and others, 2019; Førland and others, 2020). Ensemble future projections from statistical downscaling and regional climate models (RCMs) indicate a 6–7 ° C warming and a precipitation increase of on average 45% from 1971–2000 to 2071–2100 for a medium RCP 4.5 emission scenario.…”

Atmospheric rivers and associated precipitation patterns during the ACLOUD/PASCAL campaigns near Svalbard (May–June 2017): case studies using observations, reanalyses, and a regional climate model

“…Thus, from this island towards Svalbard precipitation amounts were reduced, despite, depending on the reanalysis dataset, some smaller amounts of precipitation (<10 mm accumulated during 48 hours) were noticed in HIRHAM5 model, and might be mainly related to the Foehn effect. Compared to the precipitation climatology of Svalbard region (from 1979 to 2018) that varies from 31 mm in Svalbard Airport station to 127 mm in Barentsburg station, and 89 mm in Ny-Ålesund station, accumulated during Spring (March to May) (Førland et al, 2020), the amount of precipitation reaching this region during the event is small. If we look in more detail to a monthly climatology of May (from 1951May (from to 1980, where in Barentsburg station precipitation was 25 mm during an average of 14 days (Aleksandrov et al, 2005), the amount of precipitation associated to the AR (accumulated during 2 days) was around 1 mm, which is reduced compared to the climatological amounts.…”

Synoptic control on snow avalanche activity in central Spitsbergen

“…They are most frequently associated with precipitation at the Svalbard Airport AWS (Isaksen et al, 2016;Wickström et al, 2020). Synoptic types with an easterly or northerly airflow component were found to be colder and drier than their southerly and westerly counterparts (Førland et al, 2020;Wickström et al, 2020).…”

“…Documented increases in air temperature (e.g., Isaksen et al, 2016;Nordli et al, 2020), increasing precipitation and shifting precipitation regimes (e.g., Førland et al, 2020), changing storm tracks (e.g., Wickström et al, 2019), and declining sea ice (e.g., Muckenhuber et al, 2016;Onarheim et al, 2014) have broad implications for Svalbard's physical environment. Previous research on Spitsbergen has investigated the influence of climatic changes on snowpack characteristics in the recent past (e.g., Peeters et al, 2019;van Pelt et al, 2016), but a lack of robust avalanche activity records impedes avalanche-specific analyses over longer temporal scales.…”

“…Air temperatures over Svalbard have increased on the order of 3-5 • C between 1971 and 2017, with warming particularly pronounced during the winter months (Hanssen-Bauer et al, 2019). Trends in precipitation are generally increasing but do so less clearly (e.g., Førland et al, 2020;Hanssen-Bauer et al, 2019), and increased extreme precipitation event frequency has been observed in recent decades (Hanssen-Bauer et al, 2019;Serreze et al, 2015). These changes have implications for Nordenskiöld Land's snow climate, with observed and projected increases in winter temperatures (Hanssen-Bauer et al, 2019) and rain-on-snow (ROS) event frequency (Peeters et al, 2019;Vikhamar-Schuler et al, 2016;Wickström et al, 2020), combined with shorter snow seasons (e.g., López-Moreno et al, 2016), affecting winter storm characteristics, snowpack duration and composition, and -inferentially, at least -avalanche activity.…”