The Impact of Late-Season Melting on Greenland Ice Sheet Movement

The Impact of Late-Season Melting on Greenland Ice Sheet Movement

The melting of ice has been a major concern in recent years, especially as climate change continues to impact our planet. The consequences of ice melting go beyond just the visual of polar bears stranded on melting icebergs. They include freshening of seawater, sea level rise, and changes in Earth’s temperature due to ice-albedo feedbacks. A new study published in Geophysical Research Letters focuses on the impact of late-season melting on the Greenland Ice Sheet and how it affects the movement of ice.

The study, led by Ryan Ing and his colleagues at the University of Edinburgh, looked at melt events that occurred in 2022, a year with record high seasonal air temperatures on the Greenland Ice Sheet. The researchers used satellite imagery spanning five years to study seven glaciers in west Greenland, combining ice velocities obtained from GPS and the Sentinel-1 space satellite with meteorological data from weather stations. The west Greenland Ice Sheet experienced the largest daily run-off in the late-melt season since 1950, with a significant portion of the ice sheet’s area experiencing melt events due to warm air brought over the ice sheet by an atmospheric river.

During these melt events, the subglacial drainage system beneath the ice sheet becomes overwhelmed by surface meltwater. This leads to an increase in basal water pressure, reducing basal friction and temporarily increasing the velocity of the ice sheet’s motion. However, as the summer progresses and larger subglacial channels develop, the lubrication effect decreases, slowing down the ice motion. This fluctuation in ice flow was observed to be significant, with a maximum increase of up to ~240% in ice velocity during melt events.

Despite the temporary acceleration in ice motion, the study found that the annual ice discharge of the Greenland Ice Sheet was not significantly impacted. There was an increase of only ~4.5% in ice mass loss from land and marine-terminating glaciers due to changes in ice motion. However, the total annual runoff increased by ~24% due to late-season melt events. This increase in meltwater runoff is critical, as it plays a significant role in the overall mass loss of the ice sheet.

The study suggests that while late-season melt events may not be a primary factor in ice sheet mass loss through increased ice discharge, they play a crucial role in the intensification of surface melting. With 50% of the entire Greenland Ice Sheet’s annual mass loss attributed to meltwater runoff, the effects of enhanced late melt-season events could become more important in the future as Earth’s climate continues to warm. Understanding how these events impact ice flow and mass loss is crucial for predicting the future of the Greenland Ice Sheet and its contribution to sea level rise.

The research highlights the complex interactions between late-season melting, ice flow, and mass loss on the Greenland Ice Sheet. While short-lived accelerations in ice motion may not significantly impact overall ice discharge, the increase in meltwater runoff from late-season melt events is a critical factor in the mass loss of the ice sheet. As climate change continues to impact our planet, studies like these are essential for understanding the consequences of ice melting and its implications for our environment.


Articles You May Like

Cancer-causing Flame Retardants Found in Everyday Items Can Be Absorbed Through Skin
The Mysterious Leakiness of Planetary Atmospheres
Rimless Wheel-Based Robots: A Step Forward in Robotics
The Importance of Understanding Brain Dysfunctions in Psychosis

Leave a Reply

Your email address will not be published. Required fields are marked *