Polar Chart

Introduction

A polar chart is a specialised nautical chart designed for navigation, voyage planning and the study of regions at high latitudes. It mainly covers the Arctic Ocean, Greenland, northern seas, polar archipelagos and the waters surrounding Antarctica and the sub-Antarctic islands.

Navigation in these regions presents very different challenges from those encountered in the Atlantic, Mediterranean or tropical waters. Distances are considerable, weather conditions can change rapidly, and the presence of sea ice, icebergs, remote coastlines and sparsely populated areas requires particularly careful chart planning.

A polar chart makes it possible to place a route within its wider geographical environment, plan an ocean passage and identify areas where larger-scale charts will subsequently be required. It is therefore an important planning document for experienced sailors, scientific expeditions, professional vessels, ocean-going yachts and exploration projects.

What Is a Polar Nautical Chart?

A polar nautical chart is designed to represent regions located close to the North and South Poles. It uses cartographic representations suited to high latitudes and makes it possible to visualise large maritime areas that would be difficult to represent accurately using charts designed for temperate latitudes.

In the Arctic, polar charts may cover the Arctic Ocean, Greenland, the Greenland Sea, Norwegian Sea, Barents Sea, Kara Sea, Beaufort Sea, Bering Sea and the various passages through the Canadian Arctic Archipelago.

In Antarctica, they cover areas including the Southern Ocean, Antarctic Peninsula, South Shetland Islands, Weddell Sea, Bellingshausen Sea, Amundsen Sea and Ross Sea.

These charts may provide different types of information required for maritime planning:

• coastlines and islands;

• charted depths and soundings;

• known navigational hazards;

• limits of charted areas;

• maritime routes and passages;

• known or charted ice areas;

• major geographical landmarks;

• ports and anchorages where information is available;

• information required to move on to larger-scale charts.

Why Use a Polar Chart?

The primary purpose of a polar chart is planning. In a vast region such as the Arctic or Southern Ocean, the navigator must first understand the overall geography before preparing the individual stages of the voyage.

A polar chart can, for example, be used to visualise a route between Northern Europe and Greenland, plan a voyage towards Svalbard or study a potential Northwest Passage route.

In the Southern Hemisphere, it can be used to prepare a voyage towards the Antarctic Peninsula from Ushuaia or Punta Arenas, study a route around the peninsula or understand the vast maritime areas of the Southern Ocean.

It also helps identify areas where more detailed chart coverage will be required. A small-scale planning chart never replaces a coastal or approach chart when the vessel approaches a coastline, strait, anchorage or harbour.

Navigation in the Arctic

The Arctic is one of the main areas covered by polar charts. It includes the Arctic Ocean and surrounding seas, as well as numerous archipelagos and territories characterised by particularly demanding navigation conditions.

Greenland occupies an important position between the North Atlantic and the Arctic Ocean. Areas between the east coast of Greenland, Iceland, Svalbard and Norway may be relevant to polar navigation projects.

Polar charts can also be used to plan navigation in areas such as the Barents Sea, Greenland Sea and approaches to the North Cape.

Ports and locations such as Tromsø, Longyearbyen, Reykjavik, Nuuk and Ilulissat may serve as stages or geographical references depending on the route. In more remote regions, opportunities for shelter and resupply are much more limited, which increases the importance of careful preparation.

The Northwest and Northeast Passages

Polar routes include several maritime passages of particular interest to sailors and expedition teams.

The Northwest Passage crosses the Canadian Arctic Archipelago and connects the Atlantic and Pacific Oceans through waters north of the North American continent. Its chart preparation requires numerous charts covering the straits, channels and islands of this region.

The Northeast Passage, also associated with the Northern Sea Route, follows the northern coast of Russia and crosses areas including the Kara Sea, Laptev Sea, East Siberian Sea and Chukchi Sea.

These routes are particularly sensitive to ice conditions and seasonal variations. Nautical charts are therefore only one part of the preparation and should be used together with available information on sea ice, weather, regulatory restrictions and local conditions.

Navigation in Antarctica

Antarctica presents an even more isolated maritime environment. The continent is surrounded by the Southern Ocean and several major seas that are important for polar navigation.

The Antarctic Peninsula is one of the areas most frequently visited by expedition vessels and specialised yachts. Major departure points for this region are located in Tierra del Fuego, particularly Ushuaia and, depending on the route, Punta Arenas.

A polar chart allows the navigator to visualise the Antarctic Peninsula, South Shetland Islands, Bransfield Strait and the various routes between South America and Antarctica.

Further east lie the Weddell Sea and the vast waters of the Southern Ocean. Other regions include the Bellingshausen Sea, Amundsen Sea and Ross Sea.

Admiralty, published by the United Kingdom Hydrographic Office, provides planning charts for the Antarctic region as well as charts covering different areas of the Southern Ocean and Antarctica.

Sea Ice and Icebergs

Ice is one of the defining characteristics of polar navigation.

It is important to distinguish sea ice, which forms at the surface of the ocean, from icebergs, which mainly originate from the calving of glaciers or ice shelves.

A nautical chart may show certain information relating to ice areas or provide information useful for planning. However, ice conditions are constantly changing. Cartographic information should therefore never be considered a permanent representation of the actual situation.

The navigator must supplement the chart with current ice information and operational data before and during the voyage.

This distinction is particularly important in the Arctic, where ice concentration and drift can vary considerably according to the season, but also around Antarctica, where icebergs can be encountered far from the coast.

Cartographic Projections in Polar Regions

Representing polar regions presents specific cartographic challenges. Projections commonly used at temperate latitudes become less suitable as the poles are approached.

Polar charts therefore use projections selected according to the geographical area and intended navigational purpose. The choice of projection affects the representation of distances, directions and routes.

For the navigator, it is important to understand that a route plotted on a polar chart should not necessarily be interpreted in exactly the same way as a route plotted on a conventional chart covering a mid-latitude area.

The projection, scale and geodetic datum must all be taken into account when planning a route.

Scales and Levels of Detail

As with all nautical charts, scale is an essential consideration.

A small-scale polar chart covers a very large area. It is particularly suitable for planning an ocean passage or expedition.

A larger-scale chart covers a smaller area but provides considerably more information. It becomes necessary near coastlines, in straits, around islands and when approaching ports or anchorages.

Polar navigation planning may therefore require several levels of chart coverage:

• a general chart to understand the region;

• a planning chart to prepare the route;

• a passage chart for an ocean crossing;

• a coastal chart for approaching land;

• a large-scale chart for complex areas;

• a harbour or approach chart for certain ports and anchorages.

This progression makes it possible to retain an overall view while having the level of detail required when approaching a sensitive or complex area.

Major Polar Chart Publishers

Several hydrographic offices and chart publishers provide coverage of polar regions.

SHOM provides charts covering various Arctic and northern areas, including parts of Greenland and the Norwegian Sea. Some references also cover sections of the North Atlantic and northern seas.

Admiralty, produced by the United Kingdom Hydrographic Office, provides particularly extensive international coverage. Admiralty planning charts include documents dedicated to the Arctic and Antarctic regions. Admiralty chart 4006 is a planning chart for the Arctic Region, while chart 4009 covers the Antarctic Region.

Imray also provides international coverage and references charts produced by different hydrographic offices. Its catalogue includes ocean, planning, passage and coastal charts covering many maritime regions.

For polar areas, it is also important to consider the national hydrographic authorities responsible for the waters concerned, including the hydrographic services of Canada, Norway, Denmark for Greenland, Russia, Australia and other countries with interests and territories in polar regions.

Paper Polar Charts and Electronic Navigation

Modern polar navigation generally combines paper charts with electronic navigation systems.

Electronic charts allow the navigator to use GPS positioning, display the vessel's track and work with digital cartographic information. Official Electronic Navigational Charts, or ENCs, are designed for use within appropriate electronic navigation systems such as ECDIS.

Paper charts nevertheless remain useful for planning and as an independent source of navigation information. In remote regions where technical assistance and repair facilities may be extremely limited, maintaining a reliable chart-based navigation capability can be an important part of voyage preparation.

Who Uses Polar Charts?

Polar charts are mainly intended for experienced users and projects requiring specialised preparation:

• offshore sailors and circumnavigators;

• expedition yacht crews;

• scientific research vessels;

• professional vessels;

• expedition teams;

• polar tourism vessels;

• maritime schools and training centres;

• researchers and organisations working in polar regions;

• enthusiasts interested in marine cartography and exploration.

A polar chart can also be used as an educational tool for understanding the maritime geography of the Arctic and Antarctic.

How to Choose a Polar Chart

Choosing a polar chart depends primarily on the geographical area and type of navigation planned.

It is important to check:

• the area covered;

• whether it concerns the Arctic or Antarctic;

• the chart scale;

• the cartographic projection;

• the level of detail;

• coverage of passages and straits;

• the representation of ice areas where available;

• paper or digital format;

• the publisher or hydrographic authority;

• the intended purpose: planning, passage, coastal navigation or harbour approach.

A planning chart for the Arctic or Antarctic should therefore not be selected solely according to its title. The exact geographical limits and scale must be checked to ensure that the chart corresponds to the intended voyage.

Conclusion

A polar chart is a specialised document that is essential when planning navigation at high latitudes. It provides an overview of the geography of the Arctic and Antarctic, allows ocean passages to be planned, identifies major polar routes and helps determine when larger-scale charts will be required.

In the Arctic, polar charts may cover Greenland, the Greenland Sea, Barents Sea, Beaufort Sea, Northwest and Northeast Passages or the approaches to Svalbard. In Antarctica, they cover areas including the Southern Ocean, Antarctic Peninsula, South Shetland Islands, Weddell Sea and the various maritime regions surrounding the continent.

SHOM and Admiralty polar charts are important references for several of these regions. However, they must be used together with all the other nautical information required for polar navigation, including ice information, weather forecasts, currents, regulations, local information and detailed chart coverage.

A polar chart therefore provides the essential geographical overview for planning a voyage through some of the most remote maritime environments on Earth.

FAQ – Polar Charts

What is a polar nautical chart?

A polar nautical chart is a specialised chart designed for navigation in high-latitude regions, mainly the Arctic and Antarctic. It uses cartographic representations suited to polar areas and covers oceans, seas, coastlines, islands and passages in these regions.

What is a polar chart used for?

It is primarily used to plan navigation or an expedition in a polar region, visualise an overall route and determine which larger-scale charts will be required for the different stages of a voyage.

Which regions are covered by polar charts?

Polar charts may cover the Arctic Ocean, Greenland, the Barents Sea, Greenland Sea, Beaufort Sea and Kara Sea, the Northwest and Northeast Passages, as well as the Southern Ocean, Weddell Sea, Ross Sea, Bellingshausen Sea and Antarctic Peninsula.

Which charts should be used for navigation in Antarctica?

Planning generally requires several levels of chart coverage. A planning chart is used to study the region as a whole, followed by larger-scale charts for coastal approaches, straits, islands, anchorages and more complex navigation areas.

Which charts should be used for navigation in the Arctic?

The choice depends on the geographical area. SHOM and Admiralty provide coverage of various parts of the Arctic, Greenland, northern seas and polar passages. The exact chart limits and scale should always be checked before using a chart for a specific voyage.

Do polar charts show sea ice?

Some charts provide information relating to ice, but actual ice conditions change constantly. Charted information should therefore be supplemented with up-to-date information on ice concentration and movement.

Is a polar chart sufficient for navigation in Antarctica?

No. A planning chart does not replace the larger-scale charts required for coastal approaches and complex navigation areas. It must also be supplemented with weather information, ice data, current information and other relevant nautical information.

Which publishers produce polar charts?

SHOM and Admiralty provide charts covering various Arctic and Antarctic regions. Other national hydrographic offices also produce charts for polar waters under their respective areas of responsibility. Admiralty's current catalogue includes dedicated planning charts for both the Arctic and Antarctic regions.

Which ports are used as departure points for polar navigation?

In the Arctic, ports such as Tromsø, Longyearbyen, Reykjavik, Nuuk and Ilulissat may serve as references or staging points depending on the region and voyage. For Antarctica, Ushuaia and Punta Arenas are important departure points for expeditions towards the Antarctic Peninsula.

Why are cartographic projections important in polar regions?

Representing the Earth's surface becomes particularly complex near the poles. The choice of projection affects the representation of distances, directions and routes. It is therefore important to understand the projection used and take its characteristics into account when planning a polar voyage.