Charts for Beginners

Essential Questions What is the difference between a map and a chart? What is the difference between a map and a chart? What are the different types of nautical publications? What are the different types of nautical publications? What information is available on charts? What information is available on charts?

What is the difference between a map and a chart?

Maps emphasize land forms, including the representation of relief, with shoreline represented as an approximate delineation usually at mean sea level. emphasize land forms, including the representation of relief, with shoreline represented as an approximate delineation usually at mean sea level.

Maps Are a static document which serves as a reference guide. Are a static document which serves as a reference guide. are not, and can not be used to plot a course. are not, and can not be used to plot a course. Rather it provides a predetermined course, usually a road, path, etc., to be followed. Rather it provides a predetermined course, usually a road, path, etc., to be followed. provide predetermined points-road intersections- to allow one a choice to change to another predetermined direction provide predetermined points-road intersections- to allow one a choice to change to another predetermined direction

merely indicate a surface path providing no information of the condition of the road. merely indicate a surface path providing no information of the condition of the road. For instance a map will not provide information on whether the road is under repair (except when it is a new road) or how many pot holes or other obstructions it may contain. For instance a map will not provide information on whether the road is under repair (except when it is a new road) or how many pot holes or other obstructions it may contain.

Charts have special unique characteristics including a very detailed and accurate representation of the coastline, which takes into account varying tidal levels and water forms, critical to a navigator. have special unique characteristics including a very detailed and accurate representation of the coastline, which takes into account varying tidal levels and water forms, critical to a navigator.

Charts are a working document. are a working document. are used to plot courses for navigators to follow in order to transit a certain area. are used to plot courses for navigators to follow in order to transit a certain area. take into account special conditions required for one's vessel, such as draft, bottom clearance, wrecks and obstructions which can be hazardous. take into account special conditions required for one's vessel, such as draft, bottom clearance, wrecks and obstructions which can be hazardous. Way points are identified to indicate relative position and points at which specific manoeuvres such as changing courses, must be performed. Way points are identified to indicate relative position and points at which specific manoeuvres such as changing courses, must be performed.

Charts provide detailed information on the area beneath the water surface, normally not visible to the naked eye, which can and is very critical for the safe and efficient navigation. provide detailed information on the area beneath the water surface, normally not visible to the naked eye, which can and is very critical for the safe and efficient navigation.

What are the different types of nautical publications?

Canadian Publications Notices to Mariners – Notices to Mariners – weekly, corrections to charts, moved buoys, new wharves, changes to lighthouses, underwater obstructions weekly, corrections to charts, moved buoys, new wharves, changes to lighthouses, underwater obstructions Chart No. 1 – Chart No. 1 – explains abbreviations, symbols, significance of all height and depths and related datum, chart colours, topographical features, lights and fog signals, dangers, etc. explains abbreviations, symbols, significance of all height and depths and related datum, chart colours, topographical features, lights and fog signals, dangers, etc. Canadian Sailing Directions Canadian Sailing Directions Tide and Current Tables Tide and Current Tables Annual Notices to Mariners Annual Notices to Mariners Notices to Shipping Notices to Shipping Chart Catalogues Chart Catalogues Radio Aids to Marine Navigation Radio Aids to Marine Navigation Lists of Lights, Buoys, and Fog Signals Lists of Lights, Buoys, and Fog Signals

What information is available on charts?

Title block - country, coast, the area depicted Title block - country, coast, the area depicted Chart catalogue number Chart catalogue number Surveying authority and the date of compilation Surveying authority and the date of compilation Date of edition Date of edition Natural scale Natural scale Publisher and date of publication Publisher and date of publication Printer Printer Control point Control point Chart datum Chart datum Compass roses – including magnetic declination Compass roses – including magnetic declination Navigational light properties Navigational light properties Depth – contour lines like those on a topographic map Depth – contour lines like those on a topographic map Currents Currents

Tidal information* Tidal information* Conversion tables* Conversion tables* Units of sounding* Units of sounding* Clarification of bearings* Clarification of bearings* Projection* Projection* Cautionary notes* Cautionary notes*

Types of Projections Mercator Mercator most are Mercator (cylindrical), lose accuracy towards the outer limits of the chart most are Mercator (cylindrical), lose accuracy towards the outer limits of the chart the smaller the portion of the globe to be represented on a chart, the less will be the distortion, larger-scale charts covering small areas will have less distortion than smaller-scaled charts the smaller the portion of the globe to be represented on a chart, the less will be the distortion, larger-scale charts covering small areas will have less distortion than smaller-scaled charts if a cylinder is placed around the Earth, tangent along the equator, all meridians will appear as vertical straight lines equidistantly spaced & parallels of latitude will be represented by straight lines intersecting at right angles to the meridians if a cylinder is placed around the Earth, tangent along the equator, all meridians will appear as vertical straight lines equidistantly spaced & parallels of latitude will be represented by straight lines intersecting at right angles to the meridians Conic Projections Conic Projections if a cone is placed on the Earth such that the axis of the cone coincides with the axis of the Earth, it would touch the Earth along a parallel of latitude known as the standard parallel if a cone is placed on the Earth such that the axis of the cone coincides with the axis of the Earth, it would touch the Earth along a parallel of latitude known as the standard parallel the only straight line is the central meridian, the parallels of latitude appear as arcs and the meridians are straight lines converging toward the nearest pole the only straight line is the central meridian, the parallels of latitude appear as arcs and the meridians are straight lines converging toward the nearest pole

Aids to Navigation Buoys: Buoys: These floats with a bell or light are moored (anchored) in water. These floats with a bell or light are moored (anchored) in water. They are used as a landmark, a warning of danger, or a marker of a bay or channel. They are used as a landmark, a warning of danger, or a marker of a bay or channel. Lighthouse: Lighthouse: A tower with a bright, rotating light, located on or near shore to inform a sailor that land is nearby. A tower with a bright, rotating light, located on or near shore to inform a sailor that land is nearby. Lighthouses are especially useful at night or in bad weather, when one's sight is limited. Lighthouses are especially useful at night or in bad weather, when one's sight is limited. Beacons: Beacons: A generic term for some sort of sea landmark, such as a buoy or lighthouse. A generic term for some sort of sea landmark, such as a buoy or lighthouse. Old shipwrecks: Old shipwrecks: Ships do sink, and you definitely want to avoid them so that you do not sink your vessel also. Ships do sink, and you definitely want to avoid them so that you do not sink your vessel also.