Shom C Nautical Chart – Pacific Ocean

Introduction

The Shom C nautical chart for the Pacific Ocean is a flat paper chart, generally supplied rolled, designed to represent accurately the maritime areas covered by official Shom charting in the Pacific. It is particularly suitable for planning and conducting navigation around French Polynesia, New Caledonia, Wallis and Futuna, and the various French archipelagos in the Pacific.

The Pacific Ocean covers an immense area and includes very different maritime environments: volcanic archipelagos, coral atolls, reefs, passes, lagoons, bays, anchorages, coastal areas and vast ocean spaces. A Shom C nautical chart makes it possible to move from this general view to a cartographic representation adapted to a specific area, with a scale suited to the intended use.

The Shom C Pacific Ocean range includes charts covering French Polynesia, the Tuamotu Islands, the Marquesas Islands, the Society Islands, the Austral Islands, New Caledonia, the Loyalty Islands and Wallis and Futuna. Some charts cover detailed coastal sectors, while others are intended for more general or offshore navigation.

Shom C nautical chart: a paper format suited to navigation

A Shom C chart is a flat paper nautical chart, generally supplied rolled in a tube. This format makes it possible to retain a large cartographic surface while facilitating storage when the chart is not being used.

Shom C paper is generally 120 g/m², with a format close to A0 or smaller depending on the reference. This presentation is particularly suitable for a chart table or a sufficiently large navigation-planning surface.

Paper nautical charts remain useful for preparing ocean passages, comparing several stages of a voyage and having a cartographic representation independent of electronic equipment.

Shom C Pacific charts are available at very different scales. For example, chart 7234C covering Futuna and Alofi Islands is at a scale of 1:60,000, while chart 7354C covering Fatu-Hiva and the bays of Hiva-Oa and Tahuata is at a scale of 1:70,000. These examples illustrate the importance of checking both the scale and the geographical area before selecting a chart.

Which Pacific areas are covered by Shom C charts?

The Shom C Pacific Ocean category covers maritime areas of particular importance for navigation in the French Pacific.

French Polynesia

French Polynesia is one of the main areas covered by Shom charting in the Pacific. Charts may cover, in particular:

• the Society Islands;

• Tahiti;

• Moorea;

• Raiatea;

• Taha'a;

• Huahine;

• Bora-Bora;

• the Tuamotu Islands;

• the Gambier Islands;

• the Marquesas Islands;

• the Austral Islands.

Detailed charts are particularly important in areas where navigation depends on reef passes, channels, shoals and anchorages.

Shom C references cover the Tuamotu archipelago, including individual islands and areas extending towards the Gambier Islands.

New Caledonia and the Loyalty Islands

New Caledonia is another major area covered by Shom charting in the Pacific.

Shom C nautical charts may cover Nouméa, the approaches to New Caledonia, passes, bays, anchorages and different sections of the coastline.

The Loyalty Islands are also included in the charted area. Reference 6686C, for example, covers the south-eastern part of New Caledonia and the Loyalty Islands.

Areas such as Poum, Touho, Hienghène, Île des Pins and several bays and anchorages are also represented within the Shom C Pacific Ocean range.

Wallis and Futuna

The islands of Wallis and Futuna occupy a particular position in the western Pacific.

Chart 7234C covers Futuna and Alofi at a scale of 1:60,000. This type of chart makes it possible to study the coastal area and the approaches to the islands in greater detail.

Pacific nautical charts and archipelagos

Navigation in the Pacific has one particular characteristic: the concentration of islands, atolls and reefs over extremely large distances.

In the Tuamotu Islands, the presence of atolls and reef passes requires careful interpretation of the chart. In the Marquesas Islands, volcanic relief, deep bays and sheltered areas create a different maritime configuration.

In French Polynesia, ports and anchorages such as Papeete, Taravao, Uturoa, Bora-Bora, Hiva-Oa, Atuona and Fatu-Hiva are examples of important maritime locations around which different chart scales may be required.

In New Caledonia, Nouméa, Port Moselle, Port du Sud, Hienghène, Touho, Poum and Île des Pins also illustrate the diversity of Pacific maritime areas.

These port and anchorage names are geographical examples: a particular chart does not necessarily cover every one of these locations.

Why is scale essential in the Pacific?

Scale is a fundamental consideration when choosing a nautical chart.

A small-scale chart covers a large area and is particularly suitable for offshore passage planning or studying a general route.

A larger-scale chart covers a smaller area but provides a more detailed representation of the coastline, passes, channels, soundings, hazards and port infrastructure.

The Shom range therefore distinguishes different scale categories. In the Nautic Way catalogue, Shom C Pacific charts are classified in particular according to coastal, littoral and offshore areas.

When preparing a Pacific crossing, it is therefore necessary to work with complementary scales: a general chart for the ocean passage, followed by more detailed charts for approaches to archipelagos, islands, passes and ports.

Offshore navigation and Pacific crossings

A Pacific crossing can involve several thousand nautical miles. The required charting therefore cannot normally be limited to a single chart.

A route between Panama and French Polynesia, for example, may involve studying the Central American coast, large ocean areas, the islands of French Polynesia and then the individual islands or archipelagos forming the destination.

For a circumnavigation, Pacific charts may also form part of a broader set including charts for the Atlantic, Indian Ocean and maritime areas around Asia and Australia.

The paper chart then provides an overall view of each stage and can be supplemented with coastal or harbour charts at larger scales.

Information found on a Shom C chart

Depending on the area and scale, a Shom nautical chart may provide numerous types of information useful to the navigator:

• soundings and depths;

• depth contours;

• coastlines;

• reefs and shoals;

• wrecks;

• navigational hazards;

• channels;

• passes;

• aids to navigation;

• landmarks;

• harbour infrastructure;

• anchorages;

• geographical information;

• regulatory limits and other information specific to the charted area.

In the Pacific, information concerning reefs, passes and shoals is particularly important. The chart must be interpreted according to its scale, edition date and the applicable complementary nautical information.

Differences between Shom C, L, G, Z and Raster charts

The Shom C therefore prioritises a flat, rolled presentation. It is particularly practical when the navigator wants a large cartographic surface on a chart table.

The Shom L follows the same paper-chart principle but uses a folded format that is more compact for storage.

The Shom G adds information concerning seabed characteristics and sediment distribution.

The Shom Z corresponds to Zonex variants and adds an overlay identifying exercise and firing areas.

Raster corresponds to a digital representation intended for certain computer-based and charting environments.

Shom C charts and nautical documentation

A nautical chart is one component of a broader set of navigational documentation.

When preparing navigation in the Pacific, the navigator may need to supplement charting with charts at other scales, passage charts, nautical publications, sailing guides, nautical atlases and navigation manuals.

This complementarity is particularly important when navigating through archipelagos, where preparation for an ocean crossing must be distinguished from the approach to a port, reef pass or anchorage.

Shom charting can therefore be incorporated into a navigation plan combining paper documents and digital data, depending on the equipment and navigation methods used on board.

How to choose a Shom C Pacific Ocean nautical chart

Before selecting a reference, several criteria should be checked:

• the exact geographical area;

• the name of the island, archipelago or coastal sector;

• the scale;

• the type of navigation planned;

• the final destination;

• the ports and anchorages involved;

• the passes or channels to be used;

• whether a general or detailed chart is required;

• the edition and available corrections.

A chart covering Tahiti will not necessarily meet the same requirements as a chart covering the Tuamotu Islands or New Caledonia.

The choice should therefore be based on the area actually being navigated and the scale required.

Conclusion

The Shom C Pacific Ocean nautical chart is a cartographic reference suited to planning and navigating in the many Pacific areas covered by Shom.

The range includes charts covering French Polynesia, the Tuamotu Islands, the Marquesas Islands, the Society Islands, the Austral Islands, New Caledonia, the Loyalty Islands and Wallis and Futuna. The available references use different scales, from offshore representations to detailed coastal charts.

The Shom C format, flat and generally rolled, provides a large reading surface particularly suited to route planning and studying maritime areas.

For Pacific navigation, it is essential to select the chart according to the area, scale and type of navigation. A general chart does not replace a detailed coastal chart when approaching a reef pass, anchorage or harbour.

Shom C Pacific Ocean charting therefore forms part of a broader set of documentation that also includes Shom L, G, Z and Raster charts, as well as nautical charts, nautical publications, atlases and navigation manuals required for comprehensive voyage preparation.

FAQ – Shom C Pacific Ocean Nautical Chart

What is a Shom C Pacific Ocean nautical chart?

It is a flat paper nautical chart, generally supplied rolled, covering a maritime area of the Pacific charted by Shom. Depending on its scale, it may cover an offshore, littoral or coastal area.

Which Pacific areas are covered by Shom C charts?

The range includes French Polynesia, the Tuamotu Islands, the Marquesas Islands, the Society Islands, the Austral Islands, New Caledonia, the Loyalty Islands and Wallis and Futuna.

Do Shom C charts cover Tahiti?

Yes. Shom Pacific charting includes references covering Tahiti and various areas of French Polynesia. However, the reference corresponding precisely to the navigated area and required scale must be selected.

Are there Shom C charts of the Tuamotu Islands?

Yes. Several references cover the Tuamotu archipelago and its different sectors, including areas around individual islands and routes towards the Gambier Islands.

Are there Shom C charts of New Caledonia?

Yes. The range includes charts covering Nouméa, different parts of the New Caledonian coast, the approaches to Hienghène, Poum, Touho, Île des Pins and the Loyalty Islands.

What is the difference between a Shom C and a Shom L chart?

The main difference is the physical format: a Shom C is a flat paper chart, generally supplied rolled, whereas a Shom L is folded to make storage and transport easier.

What is a Shom G chart used for?

A Shom G chart reproduces the cartographic information of a nautical chart and provides additional information about the nature and distribution of seabed sediments, particularly for activities requiring knowledge of seabed characteristics.

What is a Shom Z chart used for?

A Shom Z or Zonex chart contains an overlay identifying the limits and names of exercise and firing areas used by maritime forces.

What is a Shom Raster chart?

It is a digital representation of charting intended for use with certain compatible software or systems. It provides an electronic representation of the chart.

Which scale should be chosen for navigation in the Pacific?

It depends on the type of navigation. A small scale is suitable for a general view or an offshore passage, whereas a larger scale is required to study a coastline, reef pass, anchorage or harbour approach in greater detail.

Is one Shom C chart enough to cross the Pacific?

No. An ocean crossing generally requires several charts covering the different stages of the route, followed by more detailed charts for coastal approaches, archipelagos, reef passes and ports.

Which Pacific ports may be covered by Shom charts?

Depending on the areas covered, examples include Papeete, Taravao, Uturoa, Bora-Bora, Atuona, Fatu-Hiva, Nouméa, Hienghène, Touho, Poum and the various ports and anchorages of the French Pacific archipelagos.

Is a Shom C chart suitable for circumnavigation planning?

It can form part of circumnavigation planning for the Pacific stages of a voyage. It should be supplemented by charts covering the other oceans and by charts at scales appropriate to coastal and harbour areas.

Why use a paper chart for navigation in the Pacific?

A paper chart provides a representation independent of an electronic screen and makes it possible to visualise a large geographical area on a single surface. It is also a useful support for route planning and studying the overall itinerary.

Which documents should be used together with a Shom C chart?

Depending on the voyage, the charting can be supplemented with other nautical charts, offshore and coastal charts, nautical publications, sailing guides, atlases and navigation manuals.