A study in Nature’s Earth and Environment journal by scientists at the University of Ohio discovered rapid ice loss of the GrIS (Greenland Ice Sheet) could be irreversible and most likely ascribable to anthropogenic climate change.
Author Michaela King noted discharge is now 14% greater than when previously measured in 1985-1999 “with an observed increase in discharge of 4–5% per every weighted mean kilometer of retreat”.
The loss, approximately 495–500 Gt yr−1, is substantial enough to inflict a perpetual loss of mass, making further glacial calving almost inevitable and irreversible.
“The Greenland Ice Sheet is losing mass at accelerated rates in the 21st century, making it the largest single contributor to rising sea levels. Faster flow of outlet glaciers has substantially contributed to this loss, with the cause of speedup, and potential for future change, uncertain…”
Glacial land melting is a key contributor of sea-level rise and is estimated to increase by 70 metres if all ice caps and glaciers recede into the oceans. NASA data, which has measured oceanic changes since 1993 has calculated sea level rise over the past year alone to be 3.3 mm.
Factors contributing to sea-level rise include loss of ice sheets and thermal expansion of seawater due to human-driven climate change as a consequence of trapped atmospheric carbon.
Loss of ice sheets, including GrIS will globally influence climatic changes, including Atlantic meridional overturning circulation (AMOC), a system of currents transporting tropical warm water into the Northern Atlantic ocean affecting weather and forecast calculations.
Without the AMOC, warm water is less likely to flow towards northern Europe, increasing the likelihood of colder winters. Although detrimental outcomes for a weakening AMOC are not certain, it will no doubt affect sea life and marine animal migratory patterns.
What is certain, is that current patterns of decline for the GrIS mean sea level rise will impact coastal cities and increase flooding throughout mainland Europe and the UK. This news will be catastrophic if we do not take action immediately and has already proven disastrous for parts of the United States and the nation of Kiribati which is expected to disappear within the next 30 years.