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Monday, September 21, 2026

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NASA · Monday, September 21, 2026

Arctic melt season stopped getting longer after about 2010, NASA says

The File desk · Sep 21, 2026, 10:14 AM UTC

Status

Confirmed (NASA Earth Observatory Image of the Day, Sept. 21, 2026)

NASA’s Monday Earth Observatory Image of the Day reports a NASA-led study finding that while the Arctic sea-ice melt season lengthened dramatically since satellite records began in 1979 — and is now about 40 days longer than in 1979 — that lengthening trend unexpectedly stabilized around 2010. Most of the increase came before 2010. Since then, the average melt-season length has stayed comparatively steady even with large year-to-year swings. Researchers used satellite observations from 1979 through 2023. Co-author Linette Boisvert of NASA’s Goddard Space Flight Center says thinner ice means more year-to-year variability. The piece cautions that the pause may be temporary.

NASA’s Monday Earth Observatory Image of the Day reports a NASA-led study on the Arctic sea-ice melt season.

That season lengthened dramatically since satellite records began in 1979, and is now about 40 days longer than in 1979.

The lengthening trend unexpectedly stabilized around 2010.

Most of the increase came before 2010.

Since then, the average melt-season length has stayed comparatively steady even with large year-to-year swings.

Researchers used satellite observations from 1979 through 2023.

Co-author Linette Boisvert of NASA’s Goddard Space Flight Center says thinner ice means more year-to-year variability.

The piece cautions that the pause may be temporary.

What is still unknown or disputed

Primary sources

Every claim in this story is drawn from the documents below. If a fetch failed, that is recorded on the card.

  1. Source 1

    Arctic Melt Season Length Levels Off

    NASA Earth Observatory / NASA Science · September 21, 2026

    The Arctic sea ice melt season is now about 40 days longer than it was in 1979, according to the study. Most of the increase occurred before 2010. Since then, the average melt season length has remained relatively unchanged, despite large year-to-year fluctuations.

    https://science.nasa.gov/earth/earth-observatory/arctic-melt-season-length-levels-off/