Shom L Nautical Chart – Pacific Ocean

Shom L Pacific Ocean nautical chart: paper cartography for Pacific navigation

The Shom L Pacific Ocean nautical chart is a folded paper nautical chart designed to represent the different maritime areas covered by Shom cartography in the world’s largest ocean. It can be used to plan a route, study an ocean passage, identify archipelagos, islands, hazards, reefs, passes and harbour approaches, while providing a paper document that is easy to transport and store.

The main characteristic of the Shom L chart is its format. When folded, it measures approximately 21 × 29.7 cm, corresponding to A4 size. Once unfolded, it reaches approximately 84 × 119 cm, corresponding to an A0 format. Shom L charts are printed on 150 g/m² paper.

This presentation is particularly useful for navigators who need to carry several charts on board while keeping storage requirements under control. In the Pacific, where a voyage may require several charts covering ocean passages, archipelagos and coastal approaches, compact storage is a practical advantage.

The Shom catalogue includes charts covering areas such as French Polynesia, New Caledonia, the Coral Sea, the Tasman Sea, the Solomon Seas and various areas of the Pacific Ocean. Some charts cover very large areas, while others focus on much more detailed coastal or harbour approaches.

A nautical chart suitable for long Pacific passages

The Pacific presents specific challenges for navigation. Distances between archipelagos can be considerable, while land areas are often widely scattered. Careful chart preparation is therefore essential for passages between French Polynesia, the Cook Islands, Tonga, Fiji, Vanuatu, New Caledonia, the Solomon Islands and New Zealand.

A Shom L chart can be used at several stages of the planning process.

At a smaller scale, it provides an overall view of a large oceanic area and allows the navigator to position the main archipelagos along a route. At a larger scale, it can be used to study a coastal area, island, reef pass or harbour approach.

For a Pacific crossing, it is therefore common to work with several levels of cartography: a chart providing an overall view of the route, followed by more detailed charts for individual stages and approaches to land.

French Polynesia: Tahiti, Moorea, Raiatea, Bora-Bora and the Tuamotus

French Polynesia is one of the most emblematic sailing areas in the South Pacific.

Navigators may plan routes around Tahiti, Moorea, Huahine, Raiatea, Taha'a and Bora-Bora, as well as through much more isolated archipelagos such as the Tuamotus.

Marine cartography becomes particularly important in reef and pass areas. Approaching an atoll requires a different approach from navigating along a continental coastline. The position of reefs, passes, shoals, soundings and navigable areas must be studied carefully.

Shom charts covering French Polynesia can therefore be used for different types of navigation: inter-island passages, coastal navigation, approach to a pass, lagoon entry or anchorage planning.

The port of Papeete is naturally a major reference point for navigation around Tahiti. Other areas may include approaches to Raiatea, Bora-Bora or different Polynesian archipelagos, depending on the chart selected.

New Caledonia and the Coral Sea

New Caledonia is another major navigation area in the South Pacific.

Around Nouméa, Grande Terre and the Loyalty Islands, marine charts must distinguish between different coastal areas, reefs, passes and navigable waters.

The port of Nouméa is a major stopover for sailors undertaking a South Pacific crossing. The approaches to the city and various areas along the New Caledonian coast are covered by specific nautical cartography.

Shom also provides digital chart data for areas such as Port-Combui, Maméré, the Loyalty Islands and the Entrecasteaux Reefs.

The Coral Sea then extends the navigation area considerably. Routes may connect Australia, New Caledonia, the Solomon Islands, Vanuatu, Fiji and New Zealand.

Fiji, Vanuatu, Solomon Islands and New Zealand

The Southwest Pacific is characterised by groups of archipelagos separated by large distances.

Fiji is an important regional navigation hub, particularly around Suva, Lautoka and the various Fijian archipelagos. Vanuatu, with Port Vila and Luganville, is also an important stop for yachts crossing the Pacific.

Further northwest, the Solomon Islands and their various archipelagos present complex coastal configurations, with numerous reefs, islands and passages.

New Zealand is another major South Pacific navigation centre, particularly around Auckland, the Bay of Islands, Wellington, Tauranga and the approaches to the North Island.

For these voyages, chart selection must always take account of scale and geographical coverage. An ocean passage chart does not necessarily replace a detailed chart intended for a harbour approach or reef pass.

Information shown on a Shom L Pacific chart

Depending on the area and scale, a Shom L nautical chart may show a wide range of information essential for navigation:

• soundings and depths;

• depth contours;

• reefs and shoals;

• rocks;

• wrecks;

• aids to navigation;

• lights and light characteristics;

• landmarks;

• channels and passes;

• ports and harbour facilities;

• anchorages;

• regulatory limits;

• special areas;

• information required for route planning;

• insets providing greater detail for specific areas.

In the Pacific, reading this information is particularly important around archipelagos, coral reefs, passes and lagoons.

The importance of scale on a Pacific nautical chart

Scale is fundamental when selecting a Pacific nautical chart.

A small-scale chart can represent a very extensive ocean area. It is suitable for general passage planning and identifying major geographical features.

A larger-scale chart covers a more limited area but provides considerably more detail. It becomes essential when studying harbour approaches, a reef pass, an anchorage or a complex coastal area.

For example, planning a passage between Tahiti and New Caledonia involves two different cartographic requirements: preparation of the overall route and detailed study of the final approach.

The same principle applies to a passage between Fiji and Vanuatu, between New Caledonia and Australia, or through the Polynesian archipelagos.

Comparison of the different Shom chart formats

The Shom L is therefore mainly distinguished by its folded presentation. It retains a large cartographic surface when opened while remaining considerably more compact when stored.

Shom G charts provide additional information about the nature and distribution of seabed sediments. Shom Z charts include additional information concerning exercise and firing areas.

Raster charts are digital, georeferenced reproductions of nautical charts. Shom describes GeoTIFF products associated with printed charts and georeferenced for appropriate digital use.

Shom L or Shom C for a Pacific crossing?

The choice between a Shom L and a Shom C mainly depends on how the navigator wants to store and consult the charts.

The Shom C is particularly suitable for a chart table where a large chart can remain open. Its rolled presentation facilitates storage in a tube.

The Shom L is folded to A4 size. It is therefore easier to transport, organise and store in a chart portfolio.

For a yacht undertaking a long Pacific crossing, storage can become a significant logistical issue. The distances involved often require several charts, different scales and multiple geographical areas.

The folded format can make it easier to organise the cartographic documents while still providing a large reading surface when the chart is opened.

The Shom L as a route-planning tool

A paper chart provides a useful way of gaining an overall view of a voyage.

Before a Pacific crossing, it allows the navigator to visualise distances between archipelagos, possible stopovers and the different stages of a route.

It can also be used to plan course changes, identify complex navigation areas and organise approaches to ports.

For navigation around Papeete, Nouméa, Suva, Port Vila, Auckland or other Pacific ports, a paper chart provides a geographical representation independent of the navigation screen.

It can therefore complement the electronic navigation systems used on board.

Choosing a Shom L Pacific Ocean nautical chart

Before selecting a Shom L chart for the Pacific, it is important to check:

• the exact geographical area;

• the chart number;

• the chart title;

• the scale;

• the geographical coverage;

• the ports concerned;

• the archipelagos and islands covered;

• the passes and approaches to be studied;

• the type of navigation planned;

• the edition and available corrections.

In the Pacific, this verification is particularly important because of the enormous size of the region. Two charts covering the same archipelago may meet very different needs depending on their scale.

Cartography adapted to the diversity of the Pacific

The Pacific Ocean encompasses very different maritime environments: offshore navigation, volcanic archipelagos, coral atolls, reefs, lagoons, large islands, continental coastlines and modern ports.

A Shom L nautical chart can therefore be used at different stages of a voyage: passage planning, navigation between archipelagos, approach to an island, preparation of a stopover or study of a coastal area.

The areas around Tahiti, the Tuamotus, New Caledonia, Fiji, Vanuatu, the Solomon Islands and New Zealand illustrate this diversity.

The chart should always be selected according to its scale, geographical coverage and the type of navigation planned.

Conclusion

The Shom L Pacific Ocean nautical chart is a particularly practical paper resource for planning and undertaking navigation in the Pacific.

Its folded A4 format allows compact storage, while its unfolded large format provides a substantial cartographic surface. It can be used for ocean passage planning, navigation between archipelagos, harbour approaches and the study of coastal areas.

In the South Pacific, the areas of French Polynesia, Tahiti, Moorea, Raiatea, Bora-Bora, the Tuamotus, New Caledonia, Nouméa, Fiji, Vanuatu, the Solomon Islands and New Zealand illustrate the diversity of cartographic requirements.

Selecting a Shom L chart should always be based on the exact geographical area, scale and type of navigation planned. For an ocean crossing, several levels of cartography may be required: an overall view of the route, regional navigation charts and more detailed charts for approaches and complex areas.

FAQ – Shom L Pacific Ocean nautical charts

What is a Shom L Pacific Ocean nautical chart?

It is a Shom paper nautical chart presented in a folded format. Depending on the reference, it covers different areas of the Pacific Ocean, including French Polynesia, New Caledonia and parts of the South Pacific.

What is the format of a Shom L Pacific chart?

When folded, it measures approximately 21 × 29.7 cm, corresponding to A4 size. When fully unfolded, it reaches approximately 84 × 119 cm, corresponding to A0 size.

Is a Shom L suitable for a Pacific crossing?

Yes, depending on the chart area and scale. It can be used to plan an ocean passage or a regional stage. A complete Pacific crossing may require several charts and different scales.

Are there Shom L charts for French Polynesia?

Yes. The Shom catalogue includes L charts covering French Polynesia and areas of the South Pacific.

Which areas of the Pacific are covered by Shom charts?

The catalogue includes areas of French Polynesia, New Caledonia, the Coral and Tasman Seas, as well as areas around Fiji, the Solomon Islands and other parts of the Pacific.

Which Pacific ports may be covered by these charts?

Depending on the reference, areas may include Papeete in French Polynesia, Nouméa in New Caledonia, Suva and Lautoka in Fiji, Port Vila in Vanuatu or Auckland in New Zealand.

Why is scale important in the Pacific?

Because a chart covering a very large ocean area does not provide the same level of detail as a chart dedicated to an island, reef pass, port or coastal area. A complete voyage may therefore require several scales.

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

The Shom L is folded to A4 size, whereas the Shom C is a flat paper chart, generally rolled. The Shom L prioritises compact storage, while the Shom C is particularly convenient when a large chart needs to remain open on a chart table.

What is the difference between a Shom L and a Shom G?

The Shom L is a conventional nautical chart. The Shom G provides additional sedimentological information about the nature and distribution of seabed sediments.

What is a Shom Z chart?

A Shom Z, or Zonex chart, is a nautical chart with an additional overlay identifying exercise and firing areas.

What is a Shom Raster chart?

It is a georeferenced digital reproduction of a Shom nautical chart, including GeoTIFF formats for relevant products. It is intended for compatible navigation and cartography software.

Can a Shom L paper chart complement an electronic navigation system?

Yes. It can be used to plan the route, maintain an overview of the sailing area and provide a cartographic representation independent of the electronic navigation system.

How do you choose a Shom L chart for the Pacific?

Check the chart number, title, scale, geographical coverage, archipelagos and ports covered, as well as the type of navigation planned. A long ocean passage may require several charts at different scales.