Resource Available: 2020 Sea Ice Outlook Post-Season Report

Date: 
30 March 2021

Resource Available
2020 Sea Ice Outlook Post-Season Report

Sea Ice Prediction Network–Phase 2

To access the report, go to:
https://www.arcus.org/sipn/sea-ice-outlook/2020/post-season

For questions, please contact:
Betsy Turner-Bogren
Email: betsy [at] arcus.org


The Sea Ice Prediction Network–Phase 2 SIPN2 announces the release of the 2020 Sea Ice Outlook (SIO) Post-Season Report—a community network activity led by the SIPN2 Project Team, with contributions from key partners, to advance our understanding of the state and evolution of Arctic sea ice cover.

This report includes in-depth discussions and analysis of factors impacting sea ice this past summer, the SIO contributions, regional observation, predicted spatial fields, Antarctic contributions, discussion of seasonal sea ice forecasting for the Alaska marine fishing industry, and a summary from the Sea Ice Drift Forecast Experiment (SIDFEx). This report also includes a discussion of lessons learned from the SIO Contributors Forum, results from the SIO Contributors Survey, and discussions regarding probabilistic assessment of the 2008-2020 Outlooks and an evaluation of SIO forecast skill relative to control forecasts.

Highlight from the report include:

  • The observed September monthly averaged sea-ice extent was 3.92 million square kilometers based on data from the National Snow and Ice Data Center (NSIDC) Sea Ice Index (SII).
  • A total of 110 pan-Arctic September extent forecast submissions were received during the 2020 SIO season.
  • The August median of SIO contributions, 4.30 million square kilometers, was closest to the observed September extent of 3.92 million square kilometers. The range of contributions to the August report were narrower providing a more precise forecast.
  • The ice retreated far north, particularly in the East Siberian, Laptev, and Kara seas, where extreme above-normal spring temperatures lead to early melt onset and ice retreat in the region.
  • The observed 2020 September extent in the Alaskan region had a total of 0.48 million square kilometers according to NSIDC, making it the 10th lowest of the combined Chukchi, Beaufort, and Bering seas.
  • Analysis of a 13-year sample period from 2008–2020 revealed that the SIO forecasts have outperformed persistence and the persistence of the departure from the trend line (linear trend anomaly persistence).
  • This season's networking activities included a SIO contributors survey to identify interests, and a two-day SIO Contributors Forum held in January 2021 to share successes and challenges of Arctic sea-ice prediction and identify network activities.

The Sea Ice Outlook is an effort managed by SIPN2 that provides an open process for those interested in Arctic sea ice to share ideas.

To access the report, go to:
https://www.arcus.org/sipn/sea-ice-outlook/2020/post-season

For questions, please contact:
Betsy Turner-Bogren
Email: betsy [at] arcus.org