Nearly a decade ago, global news outlets reported vast ice melt in the Arctic as sapphire lakes glimmered across the previously frozen Greenland Ice Sheet, one of the most important contributors to sea-level rise.
Nearly a decade ago, global news outlets reported vast ice melt in the Arctic as sapphire lakes glimmered across the previously frozen Greenland Ice Sheet, one of the most important contributors to sea-level rise. Now researchers have revealed the long-term impact of that extreme melt.
Using a new approach to ice-penetrating radar data, Stanford University scientists show that this melting left behind a contiguous layer of refrozen ice inside the snowpack, including near the middle of the ice sheet where surface melting is usually minimal. Most importantly, the formation of the melt layer changed the ice sheet’s behavior by reducing its ability to store future meltwater. The research appears in Nature Communications April 20.
“When you have these extreme, one-off melt years, it’s not just adding more to Greenland’s contribution to sea-level rise in that year – it’s also creating these persistent structural changes in the ice sheet itself,” said lead study author Riley Culberg, a PhD student in electrical engineering. “This continental-scale picture helps us understand what kind of melt and snow conditions allowed this layer to form.”
The 2012 melt season was caused by unusually warm temperatures exacerbated by high atmospheric pressure over Greenland – an extreme event that may have been caused or intensified by climate change. The Greenland Ice Sheet has experienced five record-breaking melt seasons since 2000, with the most recent occurring in 2019.
Read more at Stanford University
Photo Credit: Lurens via Pixabay
