Multidecadal climate and seasonal snow conditions in Svalbard

Abstract

Svalbard climate is undergoing amplified change with respect to the global mean. Changing climate conditions directly affect the evolution of the seasonal snowpack, through its impact on accumulation, melt, and moisture exchange. We analyze long‐term trends and spatial patterns of seasonal snow conditions in Svalbard between 1961 and 2012. Downscaled regional climate model output is used to drive a snow modeling system (SnowModel), with coupled modules simulating the surface energy balance and snowpack evolution. The precipitation forcing is calibrated and validated against snow depth data on a set of glaciers around Svalbard. Climate trends reveal seasonally inhomogeneous warming and a weakly positive precipitation trend, with strongest changes in the north. In response to autumn warming the date of snow onset increased (2 days decade−1), whereas in spring/summer opposing effects cause a nonsignificant trend in the snow disappearance date. Maximum snow water equivalent (SWE) in winter/spring shows a modest increase (+0.01 meters water equivalent (mwe) decade−1), while the end‐of‐summer minimum snow area fraction declined strongly (from 48% to 36%). The equilibrium line altitude is highest in relatively dry inland regions, and time series show a clear positive trend (25 m decade−1) as a result of summer warming. Finally, rain‐on‐snow in the core winter season, affecting ground ice formation and limiting access of grazing animals to food supplies, peaks during specific years (1994, 1996, 2000, and 2012) and is found to be concentrated in the lower lying coastal regions in southwestern Svalbard.

Understanding the drivers of extensive plant damage in boreal and Arctic ecosystems: Insights from field surveys in the aftermath of damage

“…The large spatial variation in damage rates may be related to local and regional variation in snow cover and rain-on-snow events. A spatial rain-on-snow model suggests that such events are more frequent in south-western Spitsbergen (van Pelt et al 2016). This indicates that damage rates might have been even higher slightly further to the south from our study areas.…”

“…Boreal regions of north-western Europe are frequently exposed to moisture advection from the North Atlantic Ocean, which leads to long shoulder seasons (autumn-winter and winter-spring transitions), and even midwinters, with temperature close to 0 °C (Førland et 2009;Groisman and Stewart 2014;Groisman et al 2016;Vikhamar-Schuler et al 2016). This situation is becoming more pronounced also for western Spitsbergen, which is subject to the most rapidly warming winter climate in the world (Hansen et al 2014;van Pelt et al 2016;Vikhamar-Schuler et al 2016). In regions with long cold-season periods characterized by mean temperature close to 0 °C, even minor changes in temperature will have large impacts on the ground environment.…”

“…1a). It is characterized by large inter-annual variability in air temperatures and steadily increasing precipitation rates and winter temperatures (Førland et al 2009;van Pelt et al 2016;Vikhamar-Schuler et al 2016). We conducted field work at 52 monitoring plots and several additional plots around the settlements of Longyearbyen (78.25° N 15.50° E) and Ny-Ålesund (78.92° N 11.93° E).…”

Dynamic Response of a High Arctic Glacier to Melt and Runoff Variations

“…Point summer balance and ELA are calculated from annual stake readings along with snow depth measurements around the stake (Van Pelt et al, 2012;Van Pelt, Kohler, et al, 2016). Stake summer balance is calculated using information of spring surface height and end-of-summer surface height, estimated by subtracting snow depth from surface height in the subsequent spring measurement.…”

Spatiotemporal patterns of rain-on-snow and basal ice in high Arctic Svalbard: detection of a climate-cryosphere regime shift

“…The western and southern coastal regions of Spitsbergen generally experience more rainfall (Van Pelt et al 2016), and thus heavier basal ice formation, compared to the inner fjord areas of Svalbard. Furthermore, on a more local scale, the positive effect of rainfall amount on basal ice thickness decreased at higher elevations (table 1), because winter precipitation is more likely to fall as snow due to lower ambient temperature at higher altitudes (see also Van Pelt et al 2016). Such an effect has also been proposed as a main explanation for why reindeer tend to climb up steep mountain slopes to forage when pastures at lower elevations are covered by ice (Hansen et al 2010).…”