Characterization of Wind Channeling Around Longyearbyen, Svalbard

• Main Author: Lonardi, Michael
• Format: Bachelor Thesis
• Language: English
• Published: Uppsala universitet, Luft-, vatten- och landskapslära 2018
• Subjects: Longyeardalen; wind channeling; snow transport; Meteorology and Atmospheric Sciences; Meteorologi och atmosfärforskning; Arctic; Longyearbyen; Svalbard; Climate change
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-354029

Due to climate change and arctic amplification, the avalanche activity is expected to increase at higher latitudes (Hall et al., 1994). The arctic settlement of Longyearbyen, Svalbard, situated inside the valley Longyeardalen, is yearly threatened by avalanche activity (Eckerstorfer & Christiansen, 2011a). The surrounding slopes are known to produce avalanche, and during the last century they have proven to be able to cause substantial damages and even fatalities (Hallerstig, 2010). Previous studies investigated magnitude and forcing of the avalanches, including a meteorological perspective (Eckerstorfer & Christiansen, 2011b). This allowed for the usage of forecasts from the weather model AROME-Arctic in order to have an avalanche bulletin.The forecast for the area of Longyearbyen suffers from the location and the insufficient resolution of its source data. The data are obtained from an AWS located at the local airport, at the mouth of a relatively wide NW/SE oriented valley. Conversely, Longyeardalen is oriented NE/SW and is narrower. Because of the topography, channeling of winds is expected to produce difference weather conditions at the two sites, generating two distinct local weather conditions (Whiteman, 2000). If these different weather conditions are not taken into account, the weather model may provide forecasts that are not reliable for the area of Longyeardalen, hence resulting in biased avalanche bulletins.In this work I compare the data from the airport, from Longyeardalen and from the plateau above in order to assess if relevant differences exist in some important meteorological parameters (temperature, wind speed and direction, precipitation) between these sites. The weather station at the airport is an official AWS while the data from the other two sites were obtained using portable weather stations deployed during a field campaign between March 1st and April 11th 2018. During this time, snow data from the slopes surrounding Longyeardalen were also obtained. These data have been used to ...