A Nautical Chart is a graphical representation of the marine environment, this provides the reader with the basic elements of the coast, like a blueprint of the sea. A chart is used as a road map for the sea really, which makes this type of map essential for navigating a boat. Another good thing about a nautical chart is that it allows you to be very economical and can potentially save you a lot of money. It allows you to pre plot your course, which allows it to be the safest and the cheapest, this is because it has all the information on the map needed to do so, the map shows, sea levels, wrecks etc… Which allow you to plot a safe course.
A very important part of a marine map is the marine depths it shows, this is extremely important to a navigator in a big ship. If they get it wrong on the navigation and go over a to shallower piece of land, the ship could hit the bottom and capsize. On a nautical chart the depths are marked with numbers, normally they have a key down the side explaining the levels. Colours can also be used to show how deep a depth is, they will be accompanied with a number but generally a colour scale or some sort of lines to.
How to use a nautical chart
A nautical map should always have a scale, especially if it is going to uses a navigation map. The scale is usually found in a free space on the map, normally around the edge some where. It is quit simple to measure how far you will be traveling, you can take a ruler or another measuring device and put it on the starting point and ending point. Then measure how long the distance is, then compare it to the scale. `
The map will have a compass heading on it, this will give the directions for; north, south, east and west. All you have to do to find out what direction you are going in is, find the end point of you journey. Then imagine putting your compass on your starting point of the map and looking at your end point, the direction the end point is from your starting point will give you the compass direction, e.g. if its directly right, thats east.
All nautical charts will have depths on them, this is quite possibly one of the most important parts of the maps, these depths give the boat driver a scale of how deep the water is in the areas he wants to travel in. It will give you a number in a area which will tell you how deep the water is. A lot of charts mark these differently, there will always be numbers but some times there will be a colour key with that or lines will mark out when it gets deeper or shallower.
The Map Key
Allot of nautical charts will come with a key, these keys are very important and can prove to be very useful and life saving. Combining this with the depths it is the best way to plot your route, for example if you are coming towards a buoy and on left is shallow water and on the right is deep water, you are going to go right because it is more safer. Also it displays ship wrecks or any crashed vessels, these are a must to avoid unless the water is that deep the vessel can go over the top of it safely.