Greenland is home to the Earth’s second largest ice sheet — and below it, a complex, but little-understood hydrological network. How this network responds to global warming could affect the stability of the ice sheet and provide researchers with critical insights.
Now, a new study led by Princeton University researchers found that as the thousands of natural meltwater lakes that form on the surface of Greenland’s ice sheet rapidly drain, they create water “blisters” between the ice and the bedrock.
The researchers discovered that these blisters push the surface of the ice upward, then cause it to gradually drop down as the water permeates into the subglacial network. This rise and fall can be used to estimate a property known as transmissivity, which characterizes the efficiency of the water networks that form between the ice and the bedrock.
The findings could shed light on how climate change will affect Greenland’s vast frozen interior as the planet warms and surface melting increases, said first author Ching-Yao Lai, an assistant professor of geosciences and atmospheric and oceanic sciences at Princeton.