These latter sources have relatively large uncertainties due to small total ice column densities. (arxiv.org)
I don't see the GL moving until after any previously built up driving force (height of unsupported ice column) has already been released (deformed to a lower height). (realclimate.org)
At − 40 °C (− 40 °F) and a supersaturation with respect to liquid water of close to 0 percent, hollow ice columns form. (britannica.com)