International Ice Charting Working Group

Overview
Meetings
Task Teams
IICWG Business
In this section
  • Rendering Links ...
  • Rendering Links ...

IICWG Business

IICWG Efforts in Antarctic Waters

IICWG Letter to JCOMM Expert Team on Marine Safety Services (Oct 2013)

WMO Sea Ice Information Services in the World

WMO's Sea Ice Information Services in the World (Aug 2017)

Satellite Observations for Ice Monitoring

The IICWG works actively with the satellite community to ensure a continuing supply of observations for ice monitoring. Interaction with the community is a regular feature of the IICWG meetings and continues throughout the year. The IICWG has commissioned one report outlining requirements for ice monitoring, contributed to several others and made regular representations to the space agencies and satellite operators.

EC-PHORS

The World Meteorological Organization (WMO) Polar and High Mountain Observations, Research, and Services activities promote and coordinate relevant programmes that are carried out in the Antarctic and Arctic regions by nations and by groups of nations. It interfaces with all WMO programmes, including the World Weather Watch and other related programmes throughout the world, meeting global needs and requirements for meteorological observations, research, and services in the polar regions. The activities are carried out under the auspices of the Executive Council Panel of Experts on Polar and High Mountain Observations, Research, and Services (EC-PHORS).

EC-PORS Update July 2011 (Aug. 2011)
Update on Key Outcomes and Initiatives of the WMO Polar Activities (Apr. 2011)

To foster cooperation with EC-PORS, the IICWG has submitted reports on its activities to each of the EC-PORS meetings:

Ice Logistics Portal

The Ice Logistics Portal was initiated as an IPY Project to provide a single website where users could get ice charts from all of the ice charting services in a convenient manner. The portal is located at https://www.icelogistics.info/.

Several documents have been considered by the IICWG concerning the future of the portal:

IICWG Multi-Lateral MOUs

Several IICWG members have signed Memoranda of Agreement to formalize their cooperative working relationships:

Color Standard and Shapefile SIGRID-3 Format

Jun. 2004: The Color Standard and SIGRID-3 formats are now official World Meteorological Organization (WMO) standards, and may be referenced as:

SIGRID-3: A Vector Archive Format for Sea Ice Charts. JCOMM Technical Report Series No. 23, 2004, WMO/TD-No. 1214.

Ice Chart Colour Code Standard. JCOMM Technical Report Series No. 24, 2004, WMO/TD-No. 1215.

These documents are available from the World Meteorological Organization - JCOMM Technical Report Series Web site, or contact John Falkingham for the Ice Chart Colour Code Standard and Florence Fetterer for the SIGRID-3 Standard.

Ice in Electronic Navigation Charts

2012: Following work by the IICWG, the JCOMM Expert Team on Sea Ice (ETSI) approved a new revision to the Ice Objects Catalogue Version 5.0 at its meeting in March 2010. This revision implements a number of recommendations to harmonize the WMO Sea Ice Nomenclature, the SIGRID-3 code, and the ENC Ice Objects. Also, a number of new objects were added to support the work of the Arctic and Antarctic Research Institute (AARI) and Transas. In February 2012, an updated draft of the Ice Objects Catalogue, Version 5.1, was released which harmonizes some terms with the WMO Sea Ice Nomenclature and the existing national practices draft. It is anticipated that version 5.1 will be formally approved later in 2012.

IICWG, together with ETSI, has been collaborating with the International Hydrographic Organization (IHO) to migrate the Ice Objects from S-57 to the new S-100 family of Electronic Chart Display & Information System (ECDIS) standards. Features, attributes, and enumerations from the Ice Objects Catalogue Version 5.0 have been encoded in the prototype IHO S-100 database as "Supplemental Geographic Information". Work remains to be done on the portrayal of ice features.

For a historical overview of ice information in electronic navigation charts see the presentation "Ice Information for Electronic Navigation Systems".

Ice Training

2nd IICWG Ice Forecaster Workshop

(updated September 2025)

The second IICWG Ice Forecaster Workshop was held from June 3-5 (1400-1700 UTC daily), organized by the IICWG Task Team on Ice Analyst and Forecaster Competencies.  The WMO Ice Forecaster Competency Framework was approved by WMO Executive Council in March 2023 to be included in WMO 1209 Compendium of Competency Frameworks. In order to support implementation of these new competencies, the IICWG has created a Task Team to develop a series of virtual and in-person workshops for Ice Services analysts and forecasters.

The objectives of the Workshop were:

  1. Extend the general knowledge of the WMO Ice Forecasting Competency Framework
  2. Short-term forecasting challenges of sea ice and icebergs and practical examples
  3. Field observations vs. ice charts, implementation of semi-automated ice-charting
  4. Ice center training programs, best practices
  5. Briefings, tailored support including support to ships in challenging ice.

The training material and recordings can be found on the following links:

Day -1 (03 June 2025)

Day 1 Video
Day 1 Google Drive Folder with presentations 

Day -2 (04 June 2025)

Day 2 Video
Day 2 Google Drive Folder with presentations

Day 3 (05 June 2025)

Day 3 Video
Day 3 Google Drive Folder with presentation

1st IICWG Ice Forecaster Workshop

(updated January 2025)

The first IICWG Ice Forecaster Workshop was held from 21-25 October 2024 (1300-1700 UTC daily), organized by the IICWG Task Team on Ice Analyst and Forecaster Competencies.  The WMO Ice Forecaster Competency Framework was approved by WMO Executive Council in March 2023 to be included in WMO 1209 Compendium of Competency Frameworks. In order to support implementation of these new competencies, the IICWG has created a Task Team to develop a series of virtual and in-person workshops for Ice Services analysts and forecasters.

The objectives of the Workshop were:

  1. Acquire the general knowledge of the WMO Ice Forecasting Competency Framework
  2. Understand the importance of ice analysis for predicting its current and near future concentration, stage of development and any other valuable characteristics, under different climate and ocean conditions.
  3. Develop professional skills in ice analysis, monitoring, forecasting and reporting to user communities

The material and recording of the presentations can be found on the following links:

Presentations: 

Google Drive folder with the presentations

Recordings:

USNIC Training Modules

The U.S. National Ice Center (USNIC) has kindly contributed its Ice Analyst Workbook for reference by IICWG participants. While some sections of the Workbook are specific to USNIC, many sections are generic and will be useful for ice analyst training anywhere.

U.S. National Ice Center: Ice Analyst Workbook (posted Nov 2011):

NRC Old-Ice Training Guide

The National Research Council (NRC) Canada developed this training guide to help personnel better distinguish old ice from first-year ice and multi-year ice from second-year ice.

Marine Training Center Engagement

Report on Marine Training Center Engagement (Oct 2020)

Ice Forecasting Models

An Inventory and Description of Ice Forecasting Models at Ice Centers: This document contains information on models at several national ice centers. (Updated Oct 2011)

Ice Chart Data Production Methods and Attributes

The information for the following Ice Services was updated between March and April 2026, except as specifically noted. The Ice Services are listed alphabetically by country.

Argentine Navy Hydrographic Service

Analysis chart frequency: daily NAVAREA VI reports, bi-weekly sea ice concentration and stage of development chart, icebergs risk charts, and sea ice edge charts.

Analysis or GIS system used:
Analysis is carried out using QGIS (EPSG:3031 projection) as the primary Geographic Information System (GIS). Satellite imagery from multiple sources is used, including optical and Synthetic Aperture Radar (SAR) data (primarily SAOCOM). Additional tools such as SNAP and SAOCOM-to-GeoTIFF converters are used for SAR data processing and integration into the GIS environment.

File format(s):

  • Vector formats: ESRI Shapefile (.shp) with associated metadata (.xml)
  • Raster formats: GeoTIFF (.tif), JPEG (.jpg) with world files (.jgw)
  • Text products: NAVAREA reports in (.txt) format
  • Distribution formats: compressed files (.zip) (including shapefiles and metadata) and web-published images

Australian Ice Service

Analysis chart frequency: Whenever satellite data availability allows; localised weekly with sub-weekly updates covering the Australian Antarctic Territory and adjacent waters roughly from 50E to 160E.

An approximate sea-ice edge analysis is published daily with the high-seas forecast for the Southern region on https://www.bom.gov.au/marine/high-seas.shtml

Analysis or GIS system used: QGIS.

File format(s): Ice Bulletins are issued in PDF format on a fee-for-service basis. 

Canadian Ice Service (CIS)

Analysis chart frequency: CIS produces different scales of charting and analysis.

  • Daily forecast ice charts at scale of 1:2M are produced for southern regions in the winter and northern regions in the summer to support shipping activities.  They depict expected ice conditions at 18UTC and based on the latest observations (satellite and other)
  • Image analysis ice charts are produced based on individual synthetic aperture radar (SAR) satellite images at the scale of the image. They are generally produced in areas where daily analyses are being created.
  • Weekly regional ice charts at scale of 1:4M are produced covering all Canadian ice-encumbered waters. 
  • Observation ice charts are created based on ship or aerial patrols.      Charts are issued at the end of each patrol.
  • Daily iceberg charts present an estimate of iceberg concentrations in the East Coast Canadian waters south of 60° N.

Analysis or GIS system used: Charts are produced with a customized ESRI ArcMap implementation.  Observation charts are created using customized software for use in the field (Farseek).

File format(s): All charts are created in PDF and GIF and available on the CIS website.  SIGRID digital files are created for all ice charting with the exception of iceberg charts.  SIGRID data is available in the CIS archive with the latest 2 weeks of products available at https://ice-glaces.ec.gc.ca/prods/sigrids/.

Chile, Navy Weather Service, (Magellan Meteorological Center)

Analysis chart frequency: Weekly Antarctic Charts for Sea Ice Concentration and Icebergs, with local reports from the Chilean Antarctic Bases (Monday, Wednesday and Friday in summer time, only Friday on winter), daily GFS modelling for ice accretion.

Analysis or GIS system used: SIGRID and QGIS.

File format(s): JPG, PNG, TXT

Danish Meteorological Institute

Analysis chart frequency: DMI produces different scales of charting and analysis for the Greenland Waters.

  • Regional sea ice charts for navigation based on available Near Real Time Synthetic Aperture Radar (SAR) data. The update frequency ranges from daily in regions with significant ice and shipping to twice weekly in regions with no or very few ships.
  • Iceberg limit, updated twice weekly, for the North Atlantic from west of Iceland (28W) to Labrador Sea near 57W. The Iceberg limit update is coordinated with the North American Ice Service.
  • Ice information in daily marine forecasts.
  • Inshore ice report in plain text (Danish/Greenlandic) for South Greenland.

Analysis or GIS system used: Ice information is produced with a customized ESRI ArcMap system. Currently in transition to ESRI ArcPro platform. 

File format(s): All charts are created in PDF and available on the DMI website.  SIGRID3 shapefiles and Iceberg Limit line shapefiles are freely available for download at https://download.dmi.dk/public/ICESERVICE/.

Finnish Ice Service

Analysis chart frequency: Daily during the Baltic Sea ice season (October-May). SST updated twice a week. On Mondays, simplified ice and SST. Charts are available from this website.
The daily analysis chart is co-produced with the Swedish Ice Service (SMHI).

Analysis or GIS system used: Customized ESRI ArcMap implementation Vanadis.

File format(s): PDF, PNG, SIGRID, NetCDF grid

Germany, Federal Maritime and Hydrographic Agency (BSH), Ice Service

Analysis chart frequency: 

Baltic Sea: once a week on changing weekdays according to satellite data availability, issued the same or the following day.

Western Baltic - North Sea: frequency depends on the amount of ice. If ice at sea has the potential to hinder navigation (even for smaller vessels) frequence is daily (including weekends and holidays).

Analysis or GIS system used: Charts are produced using QGIS with some self written python scripts for setting up the charting environment. Charts and observational ice data are stored in a publicly available PostgreSQL database.

File format(s): Adobe PDF files, Shapefiles and S411.

Historical data: Historic ice charts of the Baltic Sea are available as paper charts since winter 1926/27.  Ice charts from 1926/27 to 1966/67 have been scanned as non georeferenced *.tif files. Gridded ice charts (2’ latitude x 4’ longitude) are available since winter 1960/61 for the German coast.   Gridded data (30’x 30’) of the Baltic Sea is available since 1956/57.  Since the winter 2005/06 ice charts are available in shapefiles.  Additional to ice charts ice observations have been carried out along the German coast since winter 1896/97. This data has partly been made publicly available through a PostgresSQL data base. Daily observations for many stations are available since the winter 1939/40 and aggregated winter data since the winter 1900/01.

Icelandic Meteorological Office

Analysis chart frequency: Weekly, more frequently if ice is within Icelandic waters.

Analysis or GIS system used: Visual Weather. SQL database. Satellite. Ice maps from DMI and MET Norway.

File format(s): Adobe PDF files

Japan Meteorological Agency

Analysis chart frequency:  On Tuesdays and Fridays from December to May and every five days from November to July. Sea-ice condition charts cover the Sea of Okhotsk, the northern part of the Sea of Japan, the northern part of the Yellow Sea, the Bohai Sea and the areas of Hokkaido, the Kuril Islands and the Kamchatka Peninsula.

Analysis or GIS system used: GIMP

File format(s): All charts are first created in Windows BMP and converted to GIF, PNG, and PDF and are available on the JMA website and on the JMH website.

Norwegian Meteorological Institute

Analysis chart frequency: Weekdays Monday-Friday: Chart coverage from east Greenland to east Kara Sea. Weekly Mondays, October-April (Austral Summer): Antarctic chart covering the sector of the Weddell and Bellingshausen Seas, with a focus on the Peninsula. All charts are based on medium resolution SAR from Sentinel-1, RADARSAT-2, and RCM, supplemented by cloud-free optical and AMSR2.

Analysis or GIS system used: Charts are produced using Bifrost, the ice charting system customized from QGIS and using PostgreSQL+PostGIS database.

File format(s): All charts are created in PNG, JPEG and PDF graphics formats available on the cryo.met.no website.  SIGRID-3 digital files are created for all ice charting, and  the latest chart data is also available at cryo.met.no. S-411 format can be supplied on request.

Poland, Institute of Meteorology and Water Management (IMGW-PIB)

Analysis chart frequency: Polish Baltic Sea Ice Chart and Baltic Sea Ice Chart (two-three times a week depending on severity of ice conditions). 

Charts are made using available information during Ice Season, such as satellite data and observations. Observations are collected daily from IMGW-PIB observers, captains' offices, boatswains' offices, harbors, icebreakers, ships, and river basin management offices. Supplemented where possible by drone flights.

Analysis or GIS system used: QGIS and ESRI ArcMap

File format(s): Distribution of charts in PDF format. Charts are available, along with other ice products, on baltyk.imgw.pl.

Swedish Meteorological and Hydrological Institute (SMHI)

Analysis chart frequency: Daily during the Baltic Sea ice season. SST twice a week from mid-October up until ice chart production starts.

Analysis or GIS system used: QGIS (Vanados)

File format: PDF, PNG, Shape

Russia, Arctic and Antarctic Research Institute

(Note: This information has not been updated since February 2005.)

Analysis chart frequency: Weekly, bi-weekly, and daily regional Arctic charts. Antarctic charts are available at various frequencies while supporting the AARI R/V.

Analysis or GIS system used: ERDAS, ESRI ARCInfo.

File format(s): ArcInfo, ARCView, Shapefile, SIGRID, GIF, national vector CONTOUR-2

United States National Ice Center

Analysis chart frequency: USNIC produces varying scales of charting and analysis across different regions.

  • Daily: Daily Marginal Ice Zone (MIZ) analyses are produced for both the Arctic and Antarctic. The Interactive Multisensor Snow and Ice Mapping System (IMS) provides Northern Hemisphere snow and ice analyses. Additionally, the Alaska Sea Ice Program (ASIP) provides a daily analysis of sea ice around Alaska waters.   
  • Weekly or Routine: Hemispheric weekly ice analyses are produced for both the Arctic and Antarctic. Seasonal products are created for both the U.S. Great Lakes (daily in conjunction with CIS) and for the U.S. Mid-Atlantic region (Mon-Fri). Twice monthly Great Lakes forecasts are issued in conjunction with CIS. Antarctic icebergs greater than 20nm in extent or longer than 10nm on any axis are tracked weekly. Additionally, ASIP creates 5 day ice forecasts for Alaska waters on Mon, Wed, and Fri, and a 3-month sea ice outlook for Alaska waters issued monthly. 
  • Ad hoc/On request: Tailored support products, Impact-Based Decision Support Services (IDSS), and forecasts are generated upon request and USNIC consideration in support of specific maritime missions, icebreaking operations, emergent situations, and defense. Additionally, ASIP provides sea ice IDSS for Alaska waters in coordination with the USNIC.

Analysis or GIS system used: The USNIC operates two analysis systems. The first leverages ESRI’s ArcGIS Pro software with a customized interface and set of tools known as SIPAS (Satellite Imagery Processing and Analysis System), which is also utilized by the ASIP. The other system is IMS, an all-in-one Linux-based data processing system, analysis interface, and production environment for gridded snow and ice data. 

File format(s): 

  • SIPAS/Ice Charting: Digital vector files such as SIGRID and shapefiles are created alongside PDF, image, and gridded formats, available directly through the USNIC website. ASIP shapefiles, images, and text products for analysis, forecasts, and outlooks are available directly through the ASIP website.
  • IMS/Digital Gridded Data: GRIB, ASCII, GeoTIFF, and NETCDF formatted products from IMS are available on the USNIC website or from the formal archive hosted by the National Snow and Ice Data Center (NSIDC). 

Ice Service Climatological Products

The information below gives a quick overview of products created by various Ice Services that may be useful in evaluating climatological trends in sea ice cover. Contact the Ice Services directly for more information.

Arctic and Antarctic Research Institute

Products produced: Numerous, though not always available as digital databases. For example, probability of ice formation for Black, Caspian, and Azov Seas.

Mean (and many other statistics) total concentration by decade, 1950-1990, on AARI GDSIDB Web page.

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): 1950-1993 in SIGRID (at AARI), 1953-1990 in EASE-Grid (at NSIDC or AARI), Chart every 10 days

Argentine Navy Hydrographic Service

Products produced: Database of point observations back to the1970s or earlier

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): 1998-2000, point observations in NIC-code in .db format (like the attribute table for a shape file?). Ongoing contributions planned.

Australia (ASPeCt Project)

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): Not now, but data for 1980-1997 planned. In ASPeCt database format.

Canadian Ice Service

Products produced: Climatic Ice Atlases showing 30-year median of ice concentration (1968-1998) for Hudson Bay, East Arctic, West Arctic and Canadian east coast in GIF format. Other statistical products have been produced for some regions and are not available on our website yet; they include:

  • Climate charts products
    • 30 year median of predominant ice type (1971-2000)
    • 30 year frequency of presence of sea ice (1971-2000)
    • 30 year frequency of presence of old ice (1971-2000)
    • same types as above but for 10 year periods
    • dates of freeze-up and break-up
    • prototype anomaly charts showing departures from normal conditions for concentration and ice type; also used for interdecadal comparisons
  • Bar graphs and trends
    • weekly extents and coverages (weekly coverage can be used as chart severity index)
    • total accumulated coverages for a season (used to compare severity of ice seasons from 1968 to 2000); a variant is total accumulated old ice
    • length of seasons for all years (start of season defined as when ice reaches a threshold value)
    • minimum and maximum ice coverages
  • Several publications on sea ice climatology in Canadian waters have been produced; our latest publication is Sea Ice Climatic Atlas - East Coast of Canada - 1971-2000.

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): 1968-1998 in SIGRID; Some earlier data in SIGRID. 1968-1998 in ESRI .e00 format files as well, with SIGRID attributes (15' resolution). Ongoing contributions planned.

China, State Oceanic Administration

Products produced: Maximum annual extent for the Bohai Sea, 1952-present.

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): (To be submitted before 2001 mtg) Total and partial concentrations, stages of development on 0.1 degree grid, 1968 to present.

Danish Meteorological Institute

Products produced: Sample chart from 1990 in original (?) gridded format, available from AARI.

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): Ongoing contributions (starting with 1999) planned.

Finland Institute of Marine Research, Finnish Ice Service

Products produced: Many climatologies, atlases, and statistics on Baltic sea ice dating back to 1719 are available from the Baltic Sea Now site. One example: image showing classification of maximum extent of ice in Baltic Sea 1720-1995, characterized as extremely mild to extremely severe. Digital ice charts from 1994 on. On-line narrative summary characterizing winter conditions, with graphic of maximum ice extent (Hard copies back to 1915)

Baltic sea ice meeting country - charts contributed as a group.

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): SIGRID format (twice a week) 1960-1986. Postscript format charts 1994 on. EASE-Grid available from AARI. Ongoing contributions planned.

Germany, Federal Maritime and Hydrographic Agency (BSH), Ice Service

Products produced: On-line narrative summary of ice winter on German coast and in Baltic Sea area (from 98/99) with images of maximum extent charts.

Ice observations at the German coast between Ems and Oder since 1955.

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): Baltic sea ice meeting country - charts contributed as a group. (See Finland entry for more information).

Icelandic Meteorological Office

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): Not now, but would like to per T. Jakobsson, 10/99

Japan Meteorological Agency

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): SIGRID format charts 1971-1993. SIGRID-2 format charts 1994-1999 (Every 5 days). EASE-Grid available from AARI.

Norwegian Meteorological Institute

Products produced: Monthly charts of the ice edge. The charts are based on weekly ice edge data and indicate max, mean, and min ice extent for a month.

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): Plan to contribute SIGRID-3 format charts.

Sweden (SMHI)

Products produced: Ice statistics for fairway sections from 1870. Ice atlas for entire Baltic covering period 1960-1979 (joint SMHI-FIMR), also available in digital format (BASIS and SIGRID). Icemap GRID for the entire Baltic (twice a week) available from Feb 1998.

Baltic sea ice meeting country - charts contributed as a group.

Planned contributions: Delivery of Icemap GRID data period 1998-1999 to AARI for conversion into SIGRID format (Oct 2000). Delivery of Icemap GRID data remaining period 1980-1997 (autumn 2002).

Poland (IMGW)

Products produced:Summary of ice winter on Polish coast (from 1984/85) with maximum extent charts.

Data Bank of daily ice and meteorological observations along the Polish coast since 1955, seasonal data on winter ice conditions from 1896/97Baltic Sea Ice Meeting

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): Baltic Sea Ice Meeting

U.S. National Ice Center

Products produced: Average coverage and extent in sq. kilometers, by week of the year, for 1972-1994, 1998, and 1999, for regions of Arctic, and Antarctic.

Archive of all chart products and climatology in ArcInfo, SIGRID, and EASE-Grid formats on the Environmental Working Group Joint U.S.-Russian Arctic Sea Ice Atlas (G01962)

Contributions to the Global Digital Sea Ice Data Bank (Note - may not include holdings at AARI): 1972-1994 in SIGRID, EASE-Grid on EWG CD-ROM Atlas. Ongoing contributions planned, format TBD. Current data are available as ESRI e00 and gif files.

Interesting History

April 1, 2010 commemorates the 50 year anniversary of the first television image of Earth from space taken with the TIROS-1 weather satellite on April 1, 1960. Read the article and see the image: 50th Anniversary of First Image from TIROS-1.