What was done
The authors utilized satellite imagery taken since 1963 to examine spatial and temporal changes of an ice stream (Ice Stream B) flowing into the Ross Ice Shelf.

What was learned
The data indicate that since 1963, Ice Stream B's width has increased by nearly 4 kilometers, at a rate that is an "order of magnitude faster than models have predicted."  However, the authors report that the flow speed of the ice stream has decreased over this time period by about 50 percent.  This velocity decrease, they note "cannot be explained solely by a slight widening of the ice stream," indicating further that "such high rates of change in velocity greatly complicate the calculation of mass balance of the ice sheet."

What it means
These observations illustrate that large dynamic changes can occur in regions of the West Antarctic Ice Sheet (WAIS), but that, in the words of the authors, such changes "do not resolve the overriding question of the stability of the West Antarctic Ice Sheet."  Some mysteries, like polar ice caps, are hard to crack.