Maps And Charts 06 Flashcards
Define Maps and charts
Commonly used to describe any two dimensional projection of the earth’s surface
What features do charts have?
Lines of lat and long
Coastal outlines
Normally used for plotting
What features do maps have?
Additional topographical detail
Normally used for plotting
How is the ratio between the chart distance and earth distance represented?
A scale
Scale =chart distance ➗Earth distance
T
The larger the scale denominator, the greater the distance shown, the less detail will be shown (small scale)
True or False?
True.
What is conformality?
Angles are not expected to be preserved much beyond the intersection point. Straight lines are usually curved in the place
What are the 3 things a map must do to be conformal?
1) All angels/bearings on the earth are accurately represented on the chart.
2) Scale distortion at any point must be the same in all directions
3) Each Parallel must cross every meridian at a right angle.
Define azimuthal stereographic
Projections on a plane
What are azimuthal maps produced for?
Specialist aeronautical charts for the polar regions
Large are Meteorology forecast charts
How are Rhumb lines and Great circles depicted on the Mercator?
Rhumb lines - straight
Great Circles - concave towards the equator
How is a Mercator Produces?
Accurately projected along the line of tangency where the cylinder touches the earth.
The Mercator chart has enormously stretched the Antarctica and Greenland is 9x bigger than actual size to keep shapes undistorted.
True or False?
True.
A Mercator can also be drawn using the cylinder touching the the pole for extended for long distances north-South.
True or False?
True.
The Mercator can also be drawn with the cylinder touching the earth at a great circle for extended long distances west to east.
True.
