June Call for Sea Ice Outlook Contributions

June Call for Sea Ice Outlook Contributions
June Report (Based on May data)
Submission deadline: Friday, 12 June 2015 (firm)
All submissions should be sent to: sio2015 [at] arcus.org
Questions can be directed to: Betsy Turner-Bogren, betsy [at] arcus.org

The Sea Ice Prediction Network (SIPN) announces the call for contributions for the Sea Ice Outlook June report.

The Sea Ice Outlook provides an open process for those interested in Arctic sea ice to share ideas about the monthly September minimum sea ice extent. The monthly reports contain a variety of perspectives—from advanced numerical models to qualitative perspectives from citizen scientists. A post-season report will provide an in-depth analysis of factors driving sea ice extent this summer as well as explore the scientific methods for predicting seasonal ice extent.

For the June Outlook report, both pan-Arctic and regional outlooks will be accepted. We particularly encourage spatial forecasts and maps. Detailed instructions for contributors are below. This year, we will require a short executive summary and summary of methods. We encourage all past contributors to submit Outlooks this year and we also hope to see new participants.

Sea Ice Outlook data resources are available via the National Snow and Ice Data Center (NSIDC) SIPN Data Set webpage: http://nsidc.org/data/sipn/data-sets.html

In addition to the contributions for the monthly reports, we are also accepting "informal contributions" throughout the season that do not otherwise fit into the monthly report format. These informal contributions could include information on sea ice parameters other than extent and/or for other time periods than what is included in the regular monthly reports: http://www.arcus.org/sipn/sea-ice-outlook/2015/informal-contributions

ALL Outlook submissions should be sent to sio2015 [at] arcus.org with the following subject lines, as relevant:

An MS Word document is preferred for ease of formatting to PDF files and extracting images for the website - we will not edit your individual submission and will not post your Word document.

Submission Guidelines

The submission deadline is 6:00 pm AK Friday, 12 June 2015 (firm) and all submissions should be sent to sio2015 [at] arcus.org. Contributions received after the deadline will be posted to the website but not incorporated into the Outlook report or discussion.

Questions may be directed to Betsy Turner-Bogren, ARCUS, betsy [at] arcus.org.

Core Requirements for Pan-Arctic Contributions

You may also download a template in MS Word: SIO June Pan-Arctic Template (.docx - 116KB)


  1. *Contributor Name(s)/Group – how you would like your contribution to be labeled in the report (e.g., Wiggins et al.)

  2. *"Executive summary" about your Outlook contribution (max 300 words)
    Say in a few sentences what your Outlook contribution is and why. To the extent possible, use non-technical language.

  3. *Type of Outlook projection
    ___dynamic model ___statistical ___heuristic ____mixed or other (specify):

    If you use a model, please specify:
    Model Name ____
    Components of the model: Atmosphere__, Ocean__, Ice__, Land__,
    For models lacking an atmosphere or ocean, please describe the forcing: ___

  4. *September monthly average projection (extent in million square kilometers).
    To be consistent with the validating sea ice extent index from NSIDC, if possible please first compute the average concentration for the month and then compute the extent as the sum of area of all cells > 15%.

  5. *Short explanation of Outlook method (max 300 words)
    In addition to the short explanation, we encourage you to submit a more detailed Outlook, including discussions of uncertainties/probabilities as well as any relevant figures, imagery, and references.

    If this is a model contribution, please include method of initialization and variable used.

  6. *Projection uncertainty/probability estimate for September extent (only required if available with the method you are using)

  7. Short explanation/assessment of basis for the uncertainty estimate in #6 (1-2 sentences)

Additional (Optional) Items For Pan-Arctic Contributions

  1. Spatial forecast/map for September mean ice extent. Either images (e.g., jpg, tiff, pdf) and/or data may be provided. If data is provided, formats with geographic information included (e.g., geoTIFF) or in NetCDF are preferred, but we will work with the format provided as long as all relevant grid/projection/data format information is provided.

  2. Hindcast validation statistics for a set period. If your method has been tested in a hindcast mode, please provide summary statistics for whatever period used.

  3. Estimate for the week that the minimum daily extent will occur (expressed in date format using Sunday to denote the week (e.g., week of 14 September).

Submitting A Regional Outlook

We will focus on the regional reports later in the season (e.g., early August). However, Regional Outlooks are welcome at any time. Regional Outlook contributions should include:

  1. Region of Interest
    Please describe the region your Outlook covers; a location map showing your Outlook region is preferred.

  2. Sea Ice Parameter
    Provide a regional pattern or a single value estimate of phenological stages (i.e., melt onset, freeze onset, break-up and freeze-up dates, length of open water season) or monthly ice concentration, ice area, and ice extent. Please indicate whether you expect ice conditions to be similar, lighter (i.e., lower ice concentrations, earlier melt onset, earlier break-up, later freeze-up), or heavier (i.e., greater ice concentrations, later melt onset, later break-up, earlier freeze-up) than those of summer 2014.

  3. Outline of Methods/Techniques
    Provide the type of estimate (heuristic, statistical, ice-ocean model, traditional knowledge, etc.) with a brief description of the methodology and a short paragraph describing the physical rationale for the estimate.

  4. Estimate of Forecast Skill
    If possible, please include any estimates of past forecast skill and probability/uncertainty associated with your prediction.

Submitting Figures and Data (Optional)

Email Edward Blanchard-Wrigglesworth at ed [at] atmos.uw.edu to arrange to submit your figures and/or data or for inquiries.

These are optional but strongly encouraged for all participants whose methods provide information at the local scale. If you cannot contribute now, please read on anyway so you can take steps to provide the information in the future.

  1. Provide a spatial forecast map for September mean ice extent (e.g., jpg, tiff, pdf). If your method predicts sea ice extent (SIE) directly, average it in time and across ensemble members, if you have them, for September (giving values between 0 and 100% inclusive). If your method predicts sea ice concentration (SIC) directly, please average it in time to make a monthly mean SIC, then convert it to SIE (grid cells with SIC<15% are assigned SIE=0% and SIC>=15% are assigned SIE=100%). Finally average across ensemble members, if you have them. We refer to this field as a sea ice probability (SIP).

    Sample of SIP (i.e., ensemble mean SIE) in percent for a random year from CESM1.1. Sample of SIP (i.e., ensemble mean SIE) in percent for a random year from CESM1.1.

  2. Provide a spatial map of the first ice-free date (IFD; Julian Day when SIC<15% or SIE=0%) in 2015. Ideally the date is derived from daily frequency output of SIC. For IFD, identify ocean (SIC<15% upon initialization) with the Julian day of the start date (July 1 is day 182) and ice points that always have SIC>15% with the end date (Sep 31 is day 273). Also provide a map of one standard deviation across ensemble members, if you have them.

    Sample of IFD (first ice free date as Julian Day) ensemble mean (left) and std dev (right) for a random year from CESM1.1. Sample of IFD (first ice free date as Julian Day) ensemble mean (left) and std dev (right) for a random year from CESM1.1.

    Use the following naming convention for filenames (for example if your surname is Smith) and you are forecasting September 2015 using June initial data:

    Smith_Sep2015_Junedata_README.txt (explaining how you computed SIP and IFD, follow link for an example)

  3. Provide your data for SIP and IFD (maps in #1 and #2 above) in a format with geographic information included or in NetCDF, if possible. We will work with the format provided as long as all relevant grid/projection/data format information is provided. Provide the data on your native grid and, if possible, on a common 1 degree grid.

Include latitude (lat) and longitude (lon) grid information in degrees, and for your native grid, include gridcell area (areacello) in square meters. For SIP and IFD, identify land points in your data field with the identifier -999. Include the std. dev. of IFD (stdIFD) in the same file with IFD.

If you must submit text, please use a column format in the order: lat, lon, areacello (for the file that is on your native grid), and finally the data field. Separate columns with spaces (preferred), commas, or tabs. Do not include any information such as variables names at the beginning. Provide that information in a separate metadata file with all the information needed to understand the file.

For the common grid, please include latitudes 60N, 61N, 62N … 89N and longitudes 180W, 179W, … 179E (or 0 to 360E). No need to include areacello for the common grid.

If you provide NetCDF files use the following naming convention (or as necessary for an equivalent set of GeoTIFF files):

Smith_Sep2015_Junedata_SIP_native.nc (follow links for an example of each)

Or if you must use text, please provide all of the following files:


Tentative Schedule for the Sea Ice Outlook Reports

June Report:
* Contributions due: Friday, 12 June (firm)
* June Report released: Monday, 22 June

July Report:
* Contributions due: Friday, 10 July
* July report released: Monday, 20 July

August Report:
* Contributions due: Monday, 10 August
* August report released: Wednesday, 19 August

Post-Season Report:
* Released in December