1Institute for Marine and Atmospheric research Utrecht, Utrecht University, the Netherlands
2Centre for Glaciology, Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK
3Alfred Wegener Institute, Bremerhaven, Germany
Received: 18 Jul 2014 – Discussion started: 01 Sep 2014
Abstract. The concept of a positive feedback between ice flow and enhanced melt rates in a warmer climate fuelled the debate regarding the temporal and spatial controls on seasonal ice acceleration. Here we combine melt, basal water pressure and ice velocity data. Using 20 years of data covering the whole ablation area, we show that there is not a strong positive correlation between annual ice velocities and melt rates. Annual velocities even slightly decreased with increasing melt. Results also indicate that melt variations are most important for velocity variations in the upper ablation zone up to the equilibrium line altitude. During the extreme melt in 2012, a large velocity response near the equilibrium line was observed, highlighting the possibility of meltwater to have an impact even high on the ice sheet. This may lead to an increase of the annual ice velocity in the region above S9 and requires further monitoring.
Revised: 05 Dec 2014 – Accepted: 03 Mar 2015 – Published: 01 Apr 2015
van de Wal, R. S. W., Smeets, C. J. P. P., Boot, W., Stoffelen, M., van Kampen, R., Doyle, S. H., Wilhelms, F., van den Broeke, M. R., Reijmer, C. H., Oerlemans, J., and Hubbard, A.: Self-regulation of ice flow varies across the ablation area in south-west Greenland, The Cryosphere, 9, 603-611, doi:10.5194/tc-9-603-2015, 2015.