According to a team of researchers from the University of Leeds, the rate at which ice is disappearing across the globe is speeding up
A research team from the University of Leeds conducted a survey global ice loss using satellite data and found that loss of ice has increased within the past three decades from 0.8 trillion tons per year in the 1990s to 1.3 trillion tons per year by 2017.
The survey covers 215,000 mountain glaciers spread around the planet, the polar ice sheets in Greenland and Antarctica, the ice shelves floating around Antarctica, and sea ice drifting in the Arctic and Southern Oceans.
Melting
The biggest losses were from Arctic Sea ice (7.6 trillion tons) and Antarctic ice shelves (6.5 trillion tons) due to atmospheric melting (68 %) and oceanic melting (32%).
Half of all losses were from ice on land – including 6.1 trillion tons from mountain glaciers, 3.8 trillion tons from the Greenland ice sheet, and 2.5 trillion tons from the Antarctic ice sheet. 58 % was from the northern hemisphere and the remainder was from the southern hemisphere.
global sea levels have raised by 35 millimetres.
Researcher’s comments
Lead author Dr Thomas Slater, a Research Fellow at Leeds’ Centre for Polar Observation and Modelling, said: “Although every region we studied lost ice, losses from the Antarctic and Greenland ice sheets have accelerated the most.
“The ice sheets are now following the worst-case climate warming scenarios set out by the Intergovernmental Panel on Climate Change. Sea-level rise on this scale will have very serious impacts on coastal communities this century.”
He added: “Over the past three decades there’s been a huge international effort to understand what’s happening to individual components in Earth’s ice system, revolutionised by satellites which allow us to routinely monitor the vast and inhospitable regions where ice can be found.
“Our study is the first to combine these efforts and look at all the ice that is being lost from the entire planet.”
Solar energy
Dr Isobel Lawrence, a Research Fellow at Leeds’ Centre for Polar Observation and Modelling, said: “Sea ice loss doesn’t contribute directly to sea level rise but it does have an indirect influence. One of the key roles of Arctic sea ice is to reflect solar radiation back into space which helps keep the Arctic cool.
“As the sea ice shrinks, more solar energy is being absorbed by the oceans and atmosphere, causing the Arctic to warm faster than anywhere else on the planet.
“Not only is this speeding up sea ice melt, it’s also exacerbating the melting of glaciers and ice sheets which causes sea levels to rise.”
Report co-author and PhD researcher Inès Otosaka, also from Leeds’ Centre for Polar Observation and Modelling, said: “As well as contributing to global mean sea level rise, mountain glaciers are also critical as a freshwater resource for local communities.
“The retreat of glaciers around the world is therefore of crucial importance at both local and global scales.”
The research was funded by UK Natural Environment Research Council.
The findings of the research team, which includes the University of Edinburgh, University College London and data science specialists Earthwave, are published in European Geosciences Union’s journal The Cryosphere.
