The ice sheet covering West Antarctica is at risk of sliding off into the ocean. While further ice-sheet destabilization may be the cause of continental warming, a reduction in greenhouse gas emissions, the slow, yet inexorable loss of West Antarctic ice is likely to have stabilized climate warming. A collapse might take years but more than three meters above sea levels.
A team of researchers from the Potsdam Institute for Climate Impact Research (PIK) is now scrutinizing the ice sheet: generating trillions of tons of additional snowfall by pumping ocean water into glaciers and distributing it with snow canons. This would mean unprecedented engineering efforts and a significant environmental hazard in some of the world’s last pristine regions – to prevent long-term sea level rise from some of the world’s most densely populated areas off the coast to the US.
“The fundamental trade-off is whether or not we want humanity to buy Antarctica safe from the current inhabited coastal regions and the cultural heritage that we have built and built on our shores. In the long term, the sea level is nothing but “said Anders Levermann, a physicist at the Potsdam Institute for Climate Impact Research (PIK) and Columbia University and one of the authors. “The West Antarctic Ice Sheet is one of the tipping elements of our climate system. The West Antarctic ice sheet is practically gone until ice loss is accelerated and may not stop.”
Ice sheet to stabilize unprecedented measures
Warm ocean currents have reached the Amundsen Sea Sector of West Antarctica – a region comprising several glaciers that prone to instability due to their topographic configuration. These glaciers of underwater melting triggered their speed-up and retreat. This is already the largest ice loss for the continent and provides an accelerating contribution to global sea level rise. In their study, The Researchers employ computer simulations to project the dynamic ice loss into the future. Earlier studies suggested that even stronger reduction of greenhouse gas emissions may not prevent the collapse of the West Antarctic ice sheet.
“So what we investigated could be a potential collapse in our simulations and increased snowfall across the destabilized region,” says PIK co-author Johannes Feldmann. “In fact, we find that an awful lot of snow can actually push the ice sheet back to a stable regime and stop instability. In practice, this could be realized by an enormous redisposition of water masses – pumped out of the ocean and Snowed onto the ice sheet at a rate of several hundred billion tons per year.
Hazards and hopes between a tremendous trade-off
“We are fully aware of the disruptive character of such an intervention,” adds Feldmann. Uplifting, desalinating and heating the ocean water as well as powering snow canons would require an amount of electric power in the order of ten thousand high-end wind turbines. “Putting up a wind farm and further infrastructure in the Amundsen Sea and a vast extraction of ocean water itself would mean a significant natural reserve. The potential hazardous impacts to the region are likely to be devastating. ” Thus the risks and costs of such an unprecedented endeavor must be weighed against its potential benefits. “Also, our study does not consider future human-made global warming. So this gigantic endeavor only makes sense if the Paris Climate Agreement is retained and carbon emissions are reduced rapidly and unequivocally.”
“The Sea-Level Problem of the Breath-taking Dimension Reflects an Ice Instability to Stop Antarctica in the Snow of Antarctica,” concludes Levermann. “Yet as scientists we feel it is our duty to inform society about every and every potential option ahead of time. As unbelievable as it may seem: In order to prevent an unprecedented risk, humankind might have to make an unprecedented effort, too.”
reference –
1.Potsdam Institute for Climate Impact Research -sciencedaily, site