TY - JOUR ID - vandeWal2017Large T1 - Large and rapid melt-induced velocity changes in the ablation zone of the Greenland Ice Sheet AU - van de Wal, R.S.W. AU - Boot, W. AU - van den Broeke, M.R. AU - Smeets, C.J.P.P. AU - Tijm-Reijmer, C.H. AU - Donker, J.J.A.; AU - Oerlemans, J. JO - science VL - 321 IS - 5885 SP - 111 EP - 113 PY - 2017/06/02/ UR - https://npdc.nl/publication/9cfcf205-b6ef-5a89-a4b9-74c25e4f5e70 N2 - Continuous Global Positioning System observations reveal rapid and large ice velocity fluctuations in the western ablation zone of the Greenland Ice Sheet. Within days, ice velocity reacts to increased meltwater production and increases by a factor of 4. Such a response is much stronger and much faster than previously reported. Over a longer period of 17 years, annual ice velocities have decreased slightly, which suggests that the englacial hydraulic system adjusts constantly to the variable meltwater input, which results in a more or less constant ice flux over the years. The positive-feedback mechanism between melt rate and ice velocity appears to be a seasonal process that may have only a limited effect on the response of the ice sheet to climate warming over the next decades. ER -