Climate1979–2026million km²

Arctic sea ice extent in September

Name: Arctic sea ice extent in September
Creator: NSIDC Sea Ice Index, version 4
License: https://nsidc.org/about/use-copyright

Average Arctic sea ice extent in September, the month of minimum ice cover, from the NSIDC Sea Ice Index, since 1979.

4.81 million km²World · 2026

NSIDC Sea Ice Index, version 4Retrieved: 2026-11-05

Saved data version: retrieved 2026-11-05, ID 02144fcd7939Warehouse version at build: v45

Data coverage

World: 1979–2026; observations: 48; missing years: 0

Missing years are counted between the first and last observations. A missing value is not zero.

World

48 rows for World

Time range:

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Year

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World

Period statistics

Calculated from the values shown in this view for the selected period. Statistics follow the active display mode.

World

7.05→4.81

Total change: −31.8 %
Annual growth (CAGR): −0.8 %
Period: 1979–2026

World: 7.05 (1979) → 4.81 (2026). Change of −31.8 % over 47 years. Compound annual growth rate (CAGR) of −0.8 % per year.

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Format:

Arctic sea ice extent in September — World
Year	Country	Value
2026	World	4.81 million km²
2025	World	4.75 million km²
2024	World	4.35 million km²
2023	World	4.38 million km²
2022	World	4.9 million km²
2021	World	4.95 million km²
2020	World	4 million km²
2019	World	4.36 million km²
2018	World	4.79 million km²
2017	World	4.82 million km²
2016	World	4.53 million km²
2015	World	4.62 million km²
2014	World	5.22 million km²
2013	World	5.21 million km²
2012	World	3.57 million km²
2011	World	4.56 million km²
2010	World	4.87 million km²
2009	World	5.26 million km²
2008	World	4.69 million km²
2007	World	4.27 million km²

Source: NSIDC Sea Ice Index, version 4
Licence: Free use with citation (NSIDC)
Published by source: —
Retrieved: 2026-11-05
Indicator code in source: N_09_extent_v4.0
Unit of measure: million km²
Data version: v45

Cite

Longseries, “Arctic sea ice extent in September”. NSIDC Sea Ice Index, version 4 (N_09_extent_v4.0), 1979–2026, World. Fetterer, F., K. Knowles, W. N. Meier, M. Savoie, A. K. Windnagel and T. Stafford (2025), Sea Ice Index (G02135, Version 4), Boulder, Colorado USA, NSIDC: National Snow and Ice Data Center, doi:10.7265/a98x-0f50. Retrieved 2026-11-05. Free use with citation (NSIDC). Data version v45. Data SHA-256: 02144fcd7939a85183b71b781f0d3a8734047759fe8b321bc202cb2fb6c917ca. https://longseries.com/en/d/climate-arctic-sea-ice-september/

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Latest values

Comparison year

1 place — sorted by value, highest first
Country
World	2026	4.81 million km²4.8M km²

About this series

Sea Ice Index v4 (NSIDC): Northern Hemisphere sea ice extent, September monthly mean, 1979–. A September year joins the series once the month has ended.

Indicator definition

Area of the ocean where at least 15% of the surface is covered by ice, in million km². September is the end of the summer melt, so it shows how much ice is left after summer. Winter peak: Arctic sea ice extent in March.

How to read the data

September extent has fallen since 1979, with the lowest minimum in 2012. Single years depend on summer weather, so look at the trend, not one year. Warming context: Global temperature anomaly (NASA).

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