Antarctic sea ice extent, a measure of the ocean area in the Southern Hemisphere that is at least 15% sea ice, reached near historic lows in 2025 (NSIDC). The question will be suspended on 8 October 2026 and the outcome determined using graph data as provided by the National Snow & Ice Data Center's (NSIDC's) "Charctic Interactive Sea Ice Graph" at approximately 5:00PM ET on 9 October 2026 (Charctic Interactive Sea Ice Graph, click "Antarctic" on the left side above the graph, NSIDC - About Charctic Data). The question will close as of the date with the highest reported Antarctic sea ice extent (the most recent if there is a tie for the highest extent). Other site data are immaterial. As of the launch of this question, the highest daily reported Antarctic sea ice extent in 2025 was 17.809 million sq. km on 17 September.

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