Image illustrates glacier retreat in Svalbard.
A new study has revealed the alarming extent glaciers have shrunk over the past 40 years in a global warming hotspot for the first time - and the biggest retreat has occurred in recent years.
The research, led by the University of Bristol and published in Nature Communications, shows the vast majority (91%) of glaciers across Svalbard in the Arctic have been significantly shrinking. Findings revealed an area loss of more than 800 km2 at the glacier margins in this Norwegian group of islands since 1985.
The study also found that more than half of the glaciers (62%) undergo seasonal cycles in glacier calving – when large chunks of ice break away due to higher ocean and air temperatures.
Lead author Dr Tian Li, Senior Research Associate at the University's Glaciology Centre, said: "The scale of glacier retreats over the past few decades is astonishing, almost covering the entire Svalbard. This highlights the vulnerability of glaciers to climate change, especially in Svalbard, a region experiencing rapid warming up to seven times faster than the global average."
The research team deployed Artificial Intelligence (AI) to quickly identify glacier patterns across large areas. Using a novel AI model, they analysed millions of satellite images capturing the end positions of glaciers across the entire Svalbard.
The findings provide an unprecedented level of detail into the scale and nature of glacier loss in this region. The biggest spike in glacier retreats was detected in 2016, when the calving rates were double the average between 2010 and 2015, in response to extreme warming events.
"This was likely caused by a large-scale weather pattern called atmospheric blocking that can influence atmospheric pressures," Dr Li said.
"With the increasing frequency of atmospheric blocking and ongoing regional warming, future retreats of glaciers are expected to accelerate, resulting in greater glacier mass loss. This would change the ocean circulation and marine life environments in the Arctic."
Svalbard is one of the fastest-warming places on Earth. The low altitude of the archipelago's ice fields and geographical location in the high North Atlantic make it especially sensitive to climate change.
Co-author Jonathan Bamber, Professor of Glaciology at the University of Bristol, said: "Glacier calving is a poorly modelled and understood process that plays a crucial role in the health of a glacier. Our study provides valuable insights into what controls calving and how it responds to climate forcing in an area at the frontline of global warming."
Paper
'Pervasive glacier retreats across Svalbard from 1985 to 2023' by T. Li et al. in Nature Communications
