An analysis of changing meteorology and its relation to glacier mass balance on Svalbard between 1957 - 2018

• Main Author: Harrison, Edward John
• Format: Master Thesis
• Language: English
• Published: 2019
• Subjects: Climate change; Svalbard; Glaciers; Meteorology; Arctic; Kongsvegen; Hansbreen; Etonbreen; glacier; Sea ice
• Online Access: http://hdl.handle.net/10852/69998; http://urn.nb.no/URN:NBN:no-73197

Svalbard is an archipelago of islands covering an area of around 61000 km2 north of the Arctic Circle. The region is heavily glaciated, with more than 2100 glaciers covering around 59% of its total area. In a process known as ‘Arctic Amplification’, the Arctic is warming faster than any other area on earth, as a result there is growing interest into which meteorological parameter has the strongest control on glacier mass balance changes. By empirically analyzing 6 different meteorological parameters at 12 locations on Nordenskioldbreen, Etonbreen, Kongsvegen and Hansbreen by season over the 1957 – 2018 period, the aim of this research was to find out to what extent the climate of Svalbard has changed, how glacier mass balance is changing and which meteorological parameter is controlling these variations the most. A significant increase in mean annual air temperature of 1.25 – 3.5°C was shown when comparing the 2001 – 2018 period to the 1971 – 2000 reference era, with the largest anomalies of up to +6.5°C focused on northern Svalbard during winter. Associated with the significant warming was an increase in relative humidity during winter, a sign of decreasing sea ice and increasing lower atmospheric air temperatures. This study produced a research first in assessing precipitation anomalies by weather classification over the 2001 – 2017 period. As supported by previous research, cyclonic south-westerly winds were the most dominant weather classification during the 1957 – 2017 period. Changes in weather classification frequency were in the region of ± 2 days per season when comparing the post-millennial to reference era, with the most notable change being an increase of 3 days per season of anticyclonic easterlies during summer. Nevertheless, seasonal precipitation characteristics varied, with a slight increase in winter snow and a significant increase in winter rain observed in the post-millennium era. Summers have become drier, with a decrease in both liquid and solid precipitation seen in the same periods. Similarly, precipitation characteristics by weather type have witnessed notable changes, with daily rain and snow anomalies up to +1.75mm/d-1 and -4mm/d-1 shown when comparing the post millennium to reference era. Among these changes, mean wind speeds in both summer and winter have increased by between 11- 32%, and are thought to have contributed to mass balance changes via snow redistribution. Contrary to other studies of this type, shortwave incoming radiation was not found to act as a key control on high ablation months on any of the four study sites.