Shom C Nautical Chart – Caribbean Sea and Gulf of Mexico

The Shom C nautical chart for the Caribbean Sea and Gulf of Mexico is a flat paper nautical chart, generally supplied rolled, designed for planning navigation across a vast maritime region extending between North America, Central America, the Caribbean islands and northern South America. Depending on the scale of the chart, it can be used to prepare offshore routes, ocean passages and certain coastal navigations.

The Caribbean Sea, also known as the West Indies Sea, is a large basin bordered by the Greater and Lesser Antilles, Venezuela, Colombia, Central America and the Yucatán Peninsula. To the west, it connects with the Gulf of Mexico through the Yucatán Channel. To the north, maritime routes lead towards the Bahamas, Florida and the North Atlantic.

Shom nautical charts provide the hydrographic information required for passage planning: soundings, depths, depth contours, shoals, hazards, wrecks, reefs, aids to navigation, lights, channels, ports, anchorages and principal landmarks. For long-distance navigation, the Shom C chart provides an overview of the planned route and the main maritime areas crossed.

Cartography adapted to a vast maritime area

The Caribbean Sea and Gulf of Mexico form an extensive maritime region. A voyage in this area may cover several hundred or even several thousand nautical miles.

Routes may connect the United States, Mexico, Cuba, the Bahamas, the French West Indies, the Virgin Islands, Puerto Rico, the Dominican Republic, Haiti, Jamaica, the Cayman Islands, Colombia, Venezuela or the various archipelagos of the Lesser Antilles.

This geographical diversity means that several levels of cartography need to be distinguished:

• general charts for passage planning;

• ocean or offshore charts for long-distance routes;

• coastal charts for sailing along coastlines;

• approach charts for harbour entrances;

• larger-scale charts for channels, passages and anchorages.

The Shom catalogue includes charts covering the West Indies, the Lesser Antilles, Puerto Rico, Trinidad and the maritime areas between the Caribbean and the northern coast of South America.

A Shom C chart covering a large area allows these different archipelagos to be placed within their wider maritime environment and provides a basis for planning the overall route before moving to larger-scale charts.

Navigating in the Caribbean Sea

The Caribbean Sea is a major area for recreational sailing, commercial navigation, transatlantic passages and routes connecting North and South America.

Routes may pass through or near:

• Cuba;

• Jamaica;

• Haiti and the Dominican Republic;

• Puerto Rico;

• the Virgin Islands;

• the Cayman Islands;

• Guadeloupe;

• Martinique;

• Saint Lucia;

• Saint Vincent and the Grenadines;

• Grenada;

• Trinidad;

• the Colombian coast;

• the Venezuelan coast.

The Lesser Antilles form a succession of islands, straits, channels and passages requiring appropriate cartographic coverage. Shom distinguishes, in particular, the northern Lesser Antilles, from Anguilla to Guadeloupe, and the central sectors extending towards Saint Lucia.

A large-area Shom C chart provides an overview of these different archipelagos and allows the general route to be planned before moving to larger-scale charts.

The Gulf of Mexico

The Gulf of Mexico is a vast semi-enclosed sea bordered by the United States, Mexico and Cuba. It connects with the Caribbean Sea through the Yucatán Channel and with the Atlantic through the passages between Florida and Cuba.

Navigation in the Gulf of Mexico may involve:

• Florida;

• Louisiana;

• Mississippi;

• Alabama;

• Texas;

• the Yucatán Peninsula;

• Cuba;

• the Yucatán Channel.

The region contains numerous commercial ports, offshore areas, oil and gas platforms, shipping routes and areas subject to specific regulations.

Among the principal ports and maritime locations associated with the Gulf of Mexico are Houston, New Orleans, Mobile, Tampa, Key West, Veracruz, Tampico and Progreso.

A general chart can be used to plan a passage across the Gulf, while harbour approaches and coastal areas require larger-scale charts.

Ports and navigation points in the Caribbean

The region includes numerous ports used for commercial shipping, recreational sailing, stopovers and long-distance passages.

Major maritime ports and locations include:

• Miami and Key West in Florida;

• Havana in Cuba;

• Kingston in Jamaica;

• Santo Domingo in the Dominican Republic;

• San Juan in Puerto Rico;

• Bridgetown in Barbados;

• Fort-de-France in Martinique;

• Pointe-à-Pitre and Basse-Terre in Guadeloupe;

• Castries in Saint Lucia;

• Kingstown in Saint Vincent;

• St. George's in Grenada;

• Port of Spain in Trinidad;

• Cartagena in Colombia;

• Colón in Panama.

These ports belong to very different nautical environments. A transatlantic or inter-island route therefore requires a gradual transition from general cartography to more detailed documentation for approaches and harbour channels.

The French West Indies and the Lesser Antilles

Guadeloupe and Martinique are important reference points for navigation in the Lesser Antilles. Between the islands, routes may pass through straits and channels affected by currents, wind effects and variable weather conditions.

Navigation between Guadeloupe, Dominica, Martinique, Saint Lucia and the more southerly islands requires a precise understanding of coastlines, passages, reefs and navigational areas.

For a passage between several islands, a general chart can be used to define the route, while coastal and approach charts provide the level of detail required close to land.

Trade winds, hurricanes and weather conditions

Navigation in the Caribbean is strongly influenced by the trade winds. Depending on the season and geographical area, prevailing winds can have a significant effect on route selection, vessel speed, sea conditions and anchorage conditions.

The hurricane season is also a major factor in Caribbean and Gulf of Mexico passage planning. Tropical cyclones can affect the West Indies, Gulf of Mexico, Bahamas and the United States and Mexican coastlines.

A nautical chart does not provide real-time weather forecasts. It must therefore be used together with weather bulletins, tropical cyclone information, current data and up-to-date nautical publications.

Reefs and shoals

The tropical waters of the Caribbean contain numerous coral reefs, shoals, cays and shallow areas.

These features can be particularly important around:

• the Bahamas;

• the Cayman Islands;

• Cuba;

• the Lesser Antilles;

• the coast of Belize;

• the Yucatán Peninsula;

• certain areas of the Colombian and Venezuelan coasts.

The presence of reefs and shallow water makes the choice of scale particularly important for coastal approaches and navigation between islands.

Which scale should be chosen for Caribbean navigation?

A small-scale chart is particularly useful for planning a long-distance passage. It allows several islands, archipelagos or countries to be viewed on the same sheet.

A larger-scale chart is necessary in areas where detailed cartographic information becomes essential:

• harbour approaches;

• entering a bay;

• passage between two islands;

• navigation in a channel;

• transiting a passage;

• selecting an anchorage;

• navigating around a reef;

• approaching a maritime installation.

Complete voyage planning in the Caribbean therefore generally requires several complementary charts.

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

The Shom C chart is particularly suitable for planning an overall route and for long-distance navigation. The Shom L provides a folded presentation that is easier to consult and store. The Shom G provides specific information about sediments and seabed characteristics. The Shom Z identifies exercise and firing areas. The Shom Raster version is intended for digital use.

Preparing a passage in the Caribbean Sea and Gulf of Mexico

Complete chart planning may combine:

• a general chart of the Caribbean Sea;

• a Gulf of Mexico chart if the route passes through the area;

• offshore charts for long passages;

• coastal charts for the countries or islands visited;

• harbour approach charts;

• detailed charts of passages and channels;

• sailing directions;

• nautical atlases;

• navigation guides;

• weather information;

• current data;

• Notices to Mariners and applicable corrections.

For a France–Caribbean passage, for example, Shom chart 6561C covers a large area of the North Atlantic between France and the Caribbean, while other charts are required to provide greater detail once the vessel reaches the Caribbean region.

An international maritime region

The Caribbean Sea and Gulf of Mexico involve numerous states and territories. Routes may cross or approach the waters of the United States, Mexico, Cuba, the Bahamas, Jamaica, Haiti, the Dominican Republic, Puerto Rico, the island states of the Lesser Antilles, Colombia, Venezuela and Panama.

This international dimension requires consideration of the different applicable regulations, nautical documents and hydrographic characteristics of each area.

Shom cartography is therefore one component of overall passage planning, particularly for routes connecting the French territories in the Caribbean with the Atlantic and other areas of the region.

Conclusion

The Shom C nautical chart for the Caribbean Sea and Gulf of Mexico is designed for planning navigation across one of the largest and most geographically diverse maritime regions of the western Atlantic.

It allows sailors to plan major routes between North America, Mexico, Cuba, the Bahamas, the Caribbean islands, Central America and South America, while providing the hydrographic information required to understand the area.

The ports of Miami, Houston, New Orleans, Havana, Kingston, San Juan, Fort-de-France, Pointe-à-Pitre, Bridgetown, Port of Spain, Cartagena and Colón illustrate the importance and diversity of the maritime routes in this region.

For a complete voyage, a single chart will generally not be sufficient. Planning should combine several scales, coastal and approach charts, nautical publications, atlases, navigation manuals and the weather information required for the planned route.

FAQ – Shom C Nautical Chart for the Caribbean Sea and Gulf of Mexico

What is a Shom C nautical chart for the Caribbean Sea and Gulf of Mexico used for?

It is primarily used to plan maritime routes and passages in the Caribbean Sea, Gulf of Mexico and associated sectors of the Atlantic.

What area does the Caribbean Sea cover?

The Caribbean Sea extends between the Greater and Lesser Antilles, Central America and the northern coast of South America, with an opening towards the Gulf of Mexico through the Yucatán Channel.

What are the main ports in the region?

Major ports and maritime locations include Miami, Houston, New Orleans, Tampa, Havana, Kingston, San Juan, Bridgetown, Fort-de-France, Pointe-à-Pitre, Port of Spain, Cartagena and Colón.

Do Shom C charts cover the French West Indies?

Yes. The Shom catalogue includes charts covering the Lesser Antilles, including areas between Anguilla and Guadeloupe and sectors extending southwards towards Saint Lucia.

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

The Shom C is a flat paper chart, generally supplied rolled, whereas the Shom L is folded. They represent two physical formats of Shom nautical cartography.

What is a Shom G chart used for?

A Shom G chart provides additional information concerning seabed characteristics and sediments. It can be used for certain professional applications and fishing-related activities.

What is a Shom Z chart used for?

A Shom Z chart contains specific information concerning exercise and firing areas. These indications should be considered together with current nautical information.

What is a Shom Raster chart?

It is a digital raster nautical chart intended for use with compatible charting or navigation software.

Is a Shom C chart sufficient for crossing the Caribbean?

It can be used to plan the overall route, but a complete passage will generally require several charts at different scales for coastal approaches, islands, passages, channels, ports and anchorages.

Why are several scales required in the Caribbean?

The distances between islands can be considerable, while some coastal areas contain reefs, shoals, passages and channels. A general chart therefore does not always provide the level of detail required close to the coast.

Does a nautical chart show weather conditions or hurricanes?

No. A nautical chart primarily provides hydrographic and geographical information. For weather, hurricanes, wind, swell and currents, up-to-date information and appropriate nautical publications must be consulted.

Which documents should be used alongside a Shom C Caribbean chart?

Depending on the route, it may be necessary to supplement the chart with coastal and approach charts, sailing directions, atlases, guides, navigation manuals, weather information and up-to-date Notices to Mariners.