Snow melting and record heat in Svalbard

“In April we experienced an exceptional thermal anomaly with temperatures up to 12 degrees above normal and intermittent rain for approximately 18 days. During this period, temperatures normally fluctuate between -10 and -15 °C, while this year they remained above freezing for almost two weeks“, explains Federico Scoto, Cnr-Isp researcher and member of the project. The interaction between the heat wave and rainfall, defined as rain-on-snow events, activated surface torrents and channels of melt water on glaciers and coastal areas in advance, dynamics that usually manifest themselves in the summer months. “The heat wave, associated with rainfall, so-called rain-on-snow (RoS) events, resulted in the formation and early activation of surface meltwater streams and channels on glaciers and coastal areas around Ny-Ålesund, phenomena that are normally observed during summer. At the same time, the first 15–20 cm of the basal layer of the snow cover became completely saturated with liquid water, favoring the formation of thick layers of ice on the ground and significantly compromising access to food resources by local fauna, such as reindeer.“, adds Scotus.

The constant monitoring of environmental evolution makes use of automatic stations that collect snow measurement data in real time, a tool considered fundamental by experts for understanding the impacts of these extreme events, destined to become more frequent and intense in the coming decades. “Thanks to the snow measurement data collected in real time by our automatic station we can better understand the impacts of these extreme events, which will be increasingly frequent and intense in the coming decades. This type of activity will be critical to predicting the cascading consequences on polar ecosystems, infrastructure and logistics that support Arctic research“, warns Scotus. In addition to the impacts on the cryosphere, long periods of anomalous heat directly affect the marine ecosystem through the early transport of sediments and nutrients into the fjords. The surveys conducted on the water column inside the Kongfjorden confirmed significant variations also on the oceanographic front. “Marine conditions also recorded significant anomalies“, concludes Francesco Paladini of the Cnr-Isp. “The waters of the fjord were affected by a significant influx of Atlantic water and surface layer temperatures reached values ​​above 3°C, absolutely anomalous conditions for the spring period which is normally the coldest of the year with Eddie temperatures of around 0, -0.5°C“.