The Antarctic ocean is rapidly becoming saltier, coinciding with record-breaking sea ice loss. Since 2015, the continent has lost over 75% of its sea ice, a rate not seen since the 1970s. This decline is causing concerns, as melting ice typically makes the ocean fresher, but new satellite data shows a surprising reversal.
The loss of Antarctic sea ice has significant global implications. It reduces habitat for penguins and other ice-dwelling species, increases the number and intensity of storms, and accelerates global warming. The heat stored in the ocean is released into the atmosphere, contributing to rising sea levels globally.
A new study, led by scientists at the University of Southampton, has revealed a previously unknown feedback loop. The Southern Ocean’s salinity is rising, trapping more heat from the deep ocean, which in turn makes it harder for sea ice to reform. This upward heat flux can melt sea ice from below, creating a powerful cycle that draws up even more salt.
This phenomenon has been observed firsthand by scientists during periods of high sea surface temperature and rapid warming. The discovery highlights the urgent need for revised climate models and further research into the Antarctic system.
The findings also underscore the importance of accurate, continuous data for tracking changes in the climate. Ongoing satellite monitoring is threatened by funding cuts, which could limit our ability to adapt to the rapidly shifting climate. As one scientist notes, “We need to keep watching,” emphasizing the critical role that continued research and monitoring play in understanding and addressing this pressing issue.
Source: https://www.sciencealert.com/antarcticas-ocean-is-mysteriously-getting-saltier-spelling-end-to-sea-ice