Antarctic winds could accelerate sea level rise

Changes in the winds circling Antarctica may accelerate global sea level rise significantly more than previously estimated, a new research has warned.
Projected changes in the Antarctic winds may have a profound impact on warming ocean temperatures under the ice shelves along the coastline of West and East Antarctic.
"When we included projected Antarctic wind shifts in a detailed global ocean model, we found water up to 4 degrees Celsius warmer than current temperatures rose up to meet the base of the Antarctic ice shelves," said lead author Dr Paul Spence from the ARC Centre of Excellence for Climate System Science (ARCCSS).

"The sub-surface warming revealed in this research is on average twice as large as previously estimated with almost all of coastal Antarctica affected.
"This relatively warm water provides a huge reservoir of melt potential right near the grounding lines of ice shelves around Antarctica. It could lead to a massive increase in the rate of ice sheet melt, with direct consequences for global sea level rise," said Spence.
Using super computers at Australia's National Computational Infrastructure (NCI) Facility, researchers examined the impacts of changing winds on currents down to 700m around the coastline in greater detail than ever before.

This more detailed approach suggests changes in Antarctic coastal winds due to climate change and their impact on coastal currents could be even more important on melting of the ice shelves than the broader warming of the ocean.

"When we first saw the results it was quite a shock. It was one of the few cases where I hoped the science was wrong," said Spence.
"But the processes at play are quite simple, and well-resolved by the ocean model, so this has important implications for climate and sea-level projections. What is particularly concerning is how easy it is for climate change to increase the water temperatures beside Antarctic ice sheets," said Spence.
The research may help to explain a number of sudden and unexplained increases in global sea levels that occurred in the geological past.
The research was published in the journal Geophysical Research Letters.