Three Record-breaking Summers Reveal “Critical Transition” for Antarctic Sea Ice

NSIDC: News & Analysis and Journal of Climate, 6 March 2024

For the third summer in a row, Antarctic sea ice coverage has dropped below two million square kilometers, a threshold which had not been breached since satellite records started in the 1980s. A new study labels these increasingly intense and long-lasting extreme events as evidence that Antarctic sea ice may have undergone a “regime shift”, entering a fundamentally new state. Authors found that today’s Antarctic sea ice is now twice as variable, with anomalies persisting and accumulating over time (rather than dissipating between seasons), and dramatic lows now observed in all sectors around Antarctica. If sustained, Antarctic sea ice loss will have cascading consequences on polar ecosystems, global sea levels and climate.

NSIDC observations: https://nsidc.org/arcticseaicenews/2024/02/antarctic-sea-ice-extent-hits-third-low-in-row/
全文 https://journals.ametsoc.org/view/journals/clim/37/7/JCLI-D-23-0479.1.xml
Plain-language briefing: www.theguardian.com/world/2024/feb/24/antarctica-sea-ice-reaches-alarming-low-for-third-year-in-a-row