Will the minimum Arctic sea ice extent this summer be between 4.0m & 4.2m square kilometers?

Predicted at	2026-07-15 10:58 UTC
Prediction	14.0%
Market (at prediction)	17.4%
Market (live)	—

Analysis

The coherent ensemble core (15–20%) and the market (17.4%) both converge on the well-supported base rate for hitting a narrow 0.2M km² bin given ~±0.4M km² July-lead uncertainty and a central forecast (4.49) sitting just above the bin. The gap between trimmed mean (14%) and market (17.4%) is under the 5% threshold, the sibling market ladder is internally consistent, and there are no factual disputes a lookup could settle. I set my final probability at 16%, slightly above the trimmed mean to correct for the two artifact-driven low outliers, but this is a clear SKIP: no exploitable edge on either side.

Key Evidence

NIPR May 2026 thickness-based forecast of 4.49M km² minimum (above the bin); recent minima cluster 4.23–4.72 (2021–2025); only ~2–3 of the last ~19 years hit the narrow 0.2M km² bin (~15% base rate); July-lead forecast uncertainty (~±0.4M km²) is twice the bin width; 2026 tracking low but similar to 2025 which finished at 4.60.

Risks

It is resolution day and a hypothetical NO trade lost because a persistent Arctic dipole/warm August accelerated melt from the already-low starting point (record-low max, top-6 June), landing the minimum squarely in the 4.0–4.2 bin as in 2016/2019 — exactly the ~1-in-6 scenario the ensemble priced in.

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Update — 2026-07-22 13:31 UTC

Updated probability: 16%. Reassessed following updated evidence.

Arctic sea ice extent is currently tracking at the fourth-lowest level on record for this time of year, indicating a significant downward trend in summer ice coverage. Historical data from NSIDC and NOAA show that the annual minimum is consistently declining at a rate of over 12% per decade, often resulting in values that fall outside the 4.0 to 4.2 million square kilometer range.

Update — 2026-07-23 13:38 UTC

Updated probability: 12%. Reassessed following updated evidence.

Current projections from climate monitoring services estimate the annual minimum Arctic sea ice extent to be approximately 4.49 million square kilometers. This forecast remains above the 4.0 to 4.2 million square kilometer range, consistent with recent historical data where the 2025 minimum reached 4.60 million square kilometers.