A new and really good review article has just been published by a team of researchers. They are from the University of Leeds, the University of Edinburgh, University College London, and data science specialists Earthwave. It reveals some rather shocking statistics concerning global ice loss. The Earth lost 28 trillion tonnes of ice between 1994 and 2017 – equivalent to a sheet of ice 100 metres thick covering the whole of the UK.
Not only that, but also this revelation is the true worry – The rate at which ice is disappearing across the planet is speeding up.
Is this Peer-reviewed and published research?
Yes it is. The review article is titled “Earth’s ice imbalance” and has been published on Jan 25, 2021 within “The Cryosphere”, the open access journal of the European Geosciences Union.
Comments by the research Team on their work
Funded by the UK Natural Environment Research Council, the research shows that overall, there has been a 65% increase in the rate of ice loss over the 23-year survey. This has been mainly driven by steep rises in losses from the polar ice sheets in Antarctica and Greenland.
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.”
Dr Slater said the study was the first of its kind to examine all the ice that is disappearing on Earth, using satellite observations .
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.”
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.
Rising atmospheric temperatures have been the main driver of the decline in Arctic sea ice and mountain glaciers across the globe, while rising ocean temperatures have increased the melting of the Antarctic ice sheet. For the Greenland ice sheet and Antarctic ice shelves, ice losses have been triggered by a combination of rising ocean and atmospheric temperatures.
During the survey period, every category lost ice, but the biggest losses were from Arctic Sea ice (7.6 trillion tonnes) and Antarctic ice shelves (6.5 trillion tonnes), both of which float on the polar oceans.
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.”
Half of all losses were from ice on land – including 6.1 trillion tonnes from mountain glaciers, 3.8 trillion tonnes from the Greenland ice sheet, and 2.5 trillion tonnes from the Antarctic ice sheet. These losses have raised global sea levels by 35 millimetres.
It is estimated that for every centimetre of sea level rise, approximately a million people are in danger of being displaced from low-lying homelands.
Despite storing only 1% of the Earth’s total ice volume, glaciers have contributed to almost a quarter of the global ice losses over the study period, with all glacier regions around the world losing ice.
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.”
Just over half (58%) of the ice loss was from the northern hemisphere, and the remainder (42%) was from the southern hemisphere.
Notes
The above study author quotes were sourced from materials provided by the University of Leeds.
The actual paper itself can be found here.
The data used by the research team is also available….
- Mountain glacier mass change data from glaciological and geodetic observations are freely available at https://doi.org/10.5281/zenodo.1492141 (Zemp et al., 2019b).
- Elevation change fields from DInSAR are available via the World Data Center (https://doi.org/10.1594/PANGAEA.893612, Braun et al., 2018).
- Glacier digital elevation models and elevation change maps derived from satellite optical stereo imagery are available at https://nsidc.org/data/highmountainasia (last access: November 2020, Shean et al., 2020) and https://doi.org/10.1594/PANGAEA.903618 (Dussaillant et al., 2019a), respectively.
- Mass change data for the Antarctic and Greenland ice sheets are provided by the ice sheet mass balance intercomparison exercise (IMBIE) and are available at http://imbie.org/data-downloads/(last access: April 2020), The IMBIE Team, 2018, 2020).
- Changes in ice shelf extent can be downloaded from the Scientific Committee on Antarctic Research digital database (https://www.add.scar.org/, SCAR, 2020).
- Changes in ice shelf thickness from Adusumilli et al. (2020a) are freely available at https://doi.org/10.6075/J04Q7SHT (Adusumilli et al., 2020b).
- PIOMAS/GIOMAS data are freely available from the University of Washington Polar Science Data Center (http://psc.apl.uw.edu/data/, last access: August 2020, Zhang and Rothrock, 2003).