FINDING YOUR WAY AROUND THE SEA

By: Kirra, Sydney, Elizabeth, Zach, and Miranda.

Latitude and Longitude

• Used to help locate specific spot on the earths surface.

• Longitude: vertical• Latitude: horizontal• Equator: a line perpendicular to the axis that

divides the earth into the northern and southern hemisphere.

Other important parallels

• Tropical zone: The area of the earth that lies between the tropic of cancer and the tropic of capricorn.

• Meridians: Lines of longitude

Measurements

• Nautical mile: unit of distance used in navigation which is equal to one minute of latitude. (1.15 land miles)

Maps and Charts

• Maps and charts are 2D representations of the earth’s 3D surface.

• Maps usually show land surface• Charts usually show ocean depths

Charts

• Bathymetric Charts: shows lines connecting points of similar depth.

• Physiographic Charts: uses drawings to show varying depths of the ocean.

Instruments

• By utilizing the North Star and an instrument called a sextant a seamen can find his location as long as he was in the Northern Hemisphere.

• Chronometer: a seagoing clock that could keep accurate time and to determine longitude