That is something scientists have already seen for several glaciers in Greenland and the Western Antarctic peninsula. (earthtimes.org)
McGregor and Millican studied maps and historical accounts to calculate where on one of several glaciers they thought the impact had occurred. (scientificamerican.com)
Time series of velocities on several glaciers at different latitudes reveal seasonal fluctuations of only 7 - 8 percent so that winter velocities are only 2 percent less than the yearly mean. (realclimate.org)