CGF3M - Cooper

Circumference – 40,000 km Divided into 360 parts or straight lines that radiate from the centre of the crcle Angle between the lines called a degree Degree divided further into 60 minutes Each minute subdivided into 60 seconds Imaginary lines drawn on Earth’s surface running both north-south (meridians) and east-west (parallels)

The division of the globe, devised by ancient Greek geographers.

Parallels – lines of latitude measured in degrees north and south. Equator – runs around the middle of the globe and is defined as ZERO degrees latitude. Distance between each line is approximately 111 km Vancouver 49 degrees, 15 minutes north of the equator (49°15’N) Sydney, Australia 33 degrees, 55 minutes south of the equator (33°55’S) Meridians – lines of longitude measured in degrees east and west. Prime Meridian – Greenwich in London, England designated as starting point and ZERO degrees longitude. Converge at North and South Poles, therefore, distance in 1 degree varies from 111 km at the equator to 0 km at the poles. Vancouver 123 degrees, 04 minutes west of Greenwich meridian (123°04’W) Sydney, Australia 151 degrees, 17 minutes east (151°17’E)

Measuring latitude and longitude aided by GPS Developed by US Department of Defence for military applications and now used by scientists, industries and US! Involves a constellation of over 2 dozen satellites that calculates latitude and longitude (and elevation and speed!).

Representing the Earth on a flat surface. Maps created through a light placed at the centre of a globe and casting shadows (aka - projecting lines)on the blank surface

Three variable properties on a map projection: scale, area, and shape. Scale – ratio of the size of an object on the map, to the actual size of the object it represents. Area – multiplying east-west distance by its north- south distance = simple calculation for a rectangular piece of land. Shape – true shape of an area. Map projections can preserve one, sometimes two of the properties scale, area, and shape.

Cylindrical – transferring Earth’s latitude and longitude grid from the globe to a cylinder, which is then cut and laid flat. Least distortion at the tangent (where the globe touches the paper). Most distortion farthest from the place of contact. Eg. Mercator projection

Conic – transfer of the Earth’s latitude/longitude grid from a globe to a cone, which is then cut and laid flat. Meridians are shown as straight lines that converge toward the poles. Parallels appear as arcs of circles.

Planar – an imaginary plane touches the globe at a single point Often used to represent polar regions