Snow Distribution and Melt Modeling for Mittivakkat Glacier, Ammassalik Island, Southeast Greenland

Abstract

A physically based snow-evolution modeling system (SnowModel) that includes four submodels-the Micrometeorological Model (MicroMet), EnBal, SnowPack, and SnowTran-3D-was used to simulate five full-year evolutions of snow accumulation, distribution, sublimation, and surface melt on the Mittivakkat Glacier, in southeast Greenland. Model modifications were implemented and used 1) to adjust underestimated observed meteorological station solid precipitation until the model matched the observed Mittivakkat Glacier winter mass balance, and 2) to simulate glacier-ice melt after the winter snow accumulation had ablated. Meteorological observations from two meteorological stations were used as model inputs, and glaciological mass balance observations were used for model calibration and testing of solid precipitation observations. The modeled end-of-winter snow-water equivalent (w.eq.) accumulation increased with elevation from 200 to 700 m above sea level (ASL) in response to both elevation and topographic influences, and the simulated end-of-summer location of the glacier equilibrium line altitude was confirmed by glaciological observations and digital images. The modeled test-period-averaged annual mass balance was 150 mm w.eq. yr Ϫ1 , or ϳ15%, less than the observed. Approximately 12% of the precipitation was returned to the atmosphere by sublimation. Glacier-averaged mean annual modeled surface melt ranged from 1272 to 2221 mm w.eq. yr Ϫ1 , of which snowmelt contributed from 610 to 1040 mm w.eq. yr Ϫ1 . The surface-melt period started between mid-May and the beginning of June, and lasted until mid-September; there were as many as 120 melt days at the glacier terminus. The model simulated a Mittivakkat Glacier recession averaging Ϫ616 mm w.eq. yr Ϫ1 , almost equal to the observed Ϫ600 mm w.eq. yr Ϫ1 .

Freshwater flux to Sermilik Fjord, SE Greenland

“…SnowModel (Liston and Elder, 2006a), is a spatiallydistributed snow-evolution, ice melt, and runoff modeling system designed to be applicable over a wide range of snow and glacier landscapes, and climates found around the world, where snow and ice variations play an important role in hydrological cycling (Mernild et al, 2006a;Mernild and Liston, 2010). For a detailed description of SnowModel, including its subprograms and tests see Liston and Elder (2006a, b), Liston et al (2008), Liston and Hiemstra (2008), and Mernild and Liston (2010): MicroMet is a quasi-physically based meteorological distribution model, which defines the meteorological forcing conditions, EnBal calculates the surface energy exchanges, including melt, SnowPack simulates heat-and mass-transfer processes and snow-depth and water equivalent evolution, and SnowTran-3D is a blowing-snow model that accounts for snow redistribution by wind.…”

“…Seasonal and annual observations on the Mittivakkat Glacier include: winter, summer, and net mass-balance Hasholt, 2004, 2008), freshwater runoff (e.g., Hasholt, 1980;Hasholt andMernild, 2004, 2008), and sediment transport (Hasholt and Walling, 1992;Busskamp and Hasholt, 1996;. Modeling studies for this region include seasonal and annual climate processes (Mernild and Liston, 2010), snow cover distribution (Hasholt et al, 2003;Mernild et al, 2006a), glacier surface mass-balance (Mernild et al, 2006a(Mernild et al, , 2008b, and runoff Mernild et al, 2008b). This collection of extensive observations and model results from the Mittivakkat Glacier catchment was used to simulate the terrestrial surface runoff for the Sermilik Fjord (the study does not include ocean fluxes).…”

“…In particular, we address the simulated temporal and spatial distribution of terrestrial surface freshwater runoff to the fjord and also on a sub-catchment scale. The runoff was simulated in SnowModel (Liston and Elder, 2006a;Mernild et al, 2006a) -a state-of-the-art modeling system, based on in situ meteorological data within the Sermilik Fjord area. Runoff was initially simulated for the Mittivakkat Glacier catchment area of ∼18 km 2 and tested against observed runoff data from the Mittivakkat Glacier catchment outlet which is the only place in the Sermilik Fjord where runoff is observed.…”

Snowdrift modelling for the Vestfonna ice cap, north-eastern Svalbard

“…Particularly along the margin of larger ice caps, persistent katabatic winds become often strong enough to effectively remove snow from the surface and re-accumulate the eroded snow mass within the surrounding areas (e.g. Boon et al, 2010;Mernild et al, 2006). Once snow particles become mobile, they can be advected over long distances by the mean flow, while influencing the turbulent structure of the atmospheric boundary layer.…”

Impact of land-use changes on snow in a forested region with heavy snowfall in Hokkaido, Japan

“…MicroMet and SnowModel have been used to distribute meteorological variables and evolve snow distributions over a wide range of spatial scales (the grid increments range from 10 m to 10 km, while the spatial domains range from hundreds of metres to pan-Arctic); the models have been applied over a variety of complex landscapes, including the mountains of Colorado, Wyoming, Idaho, Arctic Alaska, Svalbard, central Norway and Greenland (e.g. Liston & Sturm, 1998Greene et al, 1999;Liston et al, 1999Liston et al, , 2007Hiemstra et al, 2002Hiemstra et al, , 2006Prasad et al, 2001;Bruland et al, 2004;Mernild et al, 2006Mernild et al, , 2007. In steep alpine environments, complex wind fields can be generated and used to drive SnowModel using regional atmospheric models (e.g.…”