Arctic open-water periods are projected to lengthen dramatically by 2100

The shrinking of Arctic-wide September sea ice extent is often cited as an indicator of modern climate change; however, the timing of seasonal sea ice retreat/advance and the length of the open-water period are often more relevant to stakeholders working at regional and local scales. This study highlights changes in regional open-water periods at multiple warming thresholds using CMIP6 models. Results show that the open-water period lengthens significantly with increasing global warming, exceeding 6 months per year across much of the Arctic with 3.5°C warming, and 6 months with 5°C warming. Model biases suggest these projections may be conservative.

Alex Crawford, Julienne Stroeve, Abigail Smith, Alexandra Jahn