Meteorological conditions on an Arctic ice cap—8 years of automatic weather station data from Austfonna, Svalbard

Abstract

Only few reliable records are available covering more than 5 years of meteorological conditions on Arctic glaciers. Here, we report on the operation of an automatic weather station at the Austfonna ice cap, Svalbard, over an 8-year period from 2004 to 2012. Time series of measured and derived quantities are analysed to characterize meteorological conditions close to the equilibrium line altitude at ∼400 m.a.s.l. The mean annual temperature is −8.3 • C but exhibits large variability such that excursions above 0 • C occur even during winter. In general, relative air humidity is high and evaluating the wind pattern, we find that moisture is primarily advected from south-easterly directions. Net radiation is dominated by shortwave radiation and, hence, surface albedo plays an important role in the radiation budget. Frequent summer snowfalls, as observed in 2008, have the ability to maintain a high albedo over much of the ablation season, thereby having large impact on the energy balance as well as on glacier mass balance. Cloudiness is assessed using records of incoming longwave radiation. Analyzing the radiation data, we find evidence for the radiation paradox, i.e. an increase of average net radiation (2004-2012) from −15.7 W m −2 for clear-sky conditions to 7.3 W m −2 during overcast skies.

Glacier-surge mechanisms promoted by a hydro-thermodynamic feedback to summer melt

“…The station has operated since April 2004 on the western flank of Austfonna at 22 • 25 12 E, 79 • 43 48 N and 370 m a.s.l. (Schuler et al, 2014). Surface crevasses were identified and mapped using ground-penetrating radar (Ramac GPR; Målå Geoscience) at a centre frequency of 800 MHz, providing structural information from the glacier surface down to a depth of ∼ 12 m (Dunse et al, 2009, Appendix C).…”

CryoSat-2 delivers monthly and inter-annual surface elevation change for Arctic ice caps

“…The distribution of glacier facies varies significantly from year to year, a consequence of large inter-annual variability in total amount of snow and summer ablation (Dunse et al, 2009). Despite mean annual temperatures of −8.3 • C, large temperature variations occur throughout the year and it is not uncommon for temperatures above 0 • C and rain events to occur in winter (Schuler et al, 2014).…”

Nitrate stable isotopes and major ions in snow and ice samples from four Svalbard sites

“…on the western side of Austfonna (data provided by T.V. Schuler, University of Oslo; see Schuler et al 2013). The second AWS is situated at 690 m a.s.l.…”