Meandering ocean currents play a crucial role in the melting of Antarctic ice shelves, which poses a significant threat to global sea levels. A recent study published in Nature Communications has shed light on the impact of the interplay between meandering ocean currents and the ocean floor in transporting warm water to shallower depths. This mechanism has been found to significantly contribute to the rapid melting of ice shelves in the Amundsen Sea of West Antarctica, particularly affecting the Pine Island and Thwaites ice shelves, which are vulnerable to warming ocean waters.
Led by Taewook Park and Yoshihiro Nakayama, an international team of researchers from the Korea Polar Research Institute, Hokkaido University, and Seoul National University utilized advanced ocean modeling techniques to investigate the underlying forces behind the rapid melting of ice shelves. Contrary to previous assumptions that attributed ice shelf melting primarily to winds over the Southern Ocean, this study highlights the crucial role played by the interactions between meandering ocean currents and the ocean floor in driving the melting process. This new understanding underscores the significance of the ocean in comprehending and addressing the impacts of climate change.
The Pine Island and Thwaites ice shelves serve as critical barriers that prevent glaciers from flowing into the ocean, but their rapid melting and potential collapse pose a significant threat to coastal communities worldwide. The study focused on the role of a layer of warm water beneath the frigid surface waters, known as the ‘modified Circumpolar Deep Water,’ in melting these ice shelves from below. The intensity and trajectory of ocean currents encircling the ice shelves play a crucial role in determining the influx of warm water, which shapes the rate of melting and contributes to the destabilization of these vulnerable ice shelves.
One key aspect that the researchers focused on was the thermocline depth, which refers to the interface between warmer deep waters and cooler surface waters. Variations in thermocline depth have been found to have a significant impact on the influx of warm water toward the ice shelves. The study challenges the conventional wisdom that intensified westerly winds north of the Amundsen Sea are the primary drivers of ocean currents along the shelf break, carrying warmer water toward ice shelf cavities, especially during El Niño events. The researchers emphasize the importance of reevaluating the role of winds in driving Antarctic ice loss, highlighting the critical role played by the interplay between meandering ocean currents and the ocean floor in accelerating ice shelf melting.
In conclusion, the study presents a novel concept that shifts the focus towards the internal oceanic processes that drive ice shelf melting in Antarctica. By highlighting the intricate interactions between meandering ocean currents, the ocean floor, and warm water influx, the research provides valuable insights that can inform future projections of Antarctic ice melt and sea level rise. The researchers stress the importance of considering the role of the ocean in understanding and addressing the impacts of climate change on vulnerable ice shelves in Antarctica, urging a comprehensive reevaluation of the underlying mechanisms driving rapid ice shelf melting in the region.
