2023's Antarctic sea ice extent is the lowest on record

Antarctic sea ice is a vitally important part of the regional and global climate. In 2023, sea ice extent fell to record lows, reaching unprecedented values for both the summer minimum, winter maximum and intervening freeze-up period. Here, we show that the extreme values observed were truly remarkable within the context of the satellite record, despite the challenge of quantifying how rare such an event might be, and discuss some contributing factors. While this could be part of a decline in sea ice associated with human-caused climate change, it is too early to say conclusively if this is the case. Antarctic sea ice extent in 2023 was astoundingly low throughout the year: from the record low summer minimum to the slow freeze-up and most recently to the record low winter maximum. Here we show that these events are truly exceptional within the context of the longer-term satellite record. It is too early to say conclusively whether these events are tied to human activity, but it appears increasingly likely that human-caused climate change is playing a role in Antarctica's sea ice lows.image