Geographer’s Tools

Maps

Globes

Graphs

Organization

• The grid that covers a globe is made of lines that run east to west and north to south. – Lines of latitude run

east-west– Lines of longitude run

north-south

Organization

• The equator is an imaginary line that circles the globe halfway between Earth.– Lines of latitude measure distances north and

south of the equator. They are also know as parallels

• The prime meridian is an imaginary line drawn from the North Pole through England to the South Pole– Lines of longitude, also called meridians,

measure distance east and west of the P.M.

Parallels and meridians measure distances in degrees. Those north of the equator are noted with an N, south with an S. Meridians can go west or eastof the prime meridian and will be noted with a W or E

Hemispheres, Continents, and Oceans

• The equator divides the world into two halves, or hemispheres. Northern and Southern

• The prime meridian and the 180 meridian divide the world into Eastern and Western Hemispheres

• 7 Continents• 4 Oceans

Maps

• Flat representations of all or part of Earth’s surface.

• There are many ways of presenting our round earth on flat maps these are called map projections– Because the earth is round, all flat maps have

some distortion– Most common maps projections are

cylindrical, conic, and flat-plane

Cylindrical Maps

• Designed as if a cylinder has been wrapped around the globe

• Meridians parallel• Landmasses near

poles larger than they really are

A Mercator map, is a type of cylindrical map projection. It is useful to navigators because it shows true direction and shape. However landmassesappear larger than they really are.

Conic Maps• Designed as if a cone

has been placed over the globe

• Most accurate along lines of latitude

• Retains almost true size and shapes of landmasses

Most useful for areas with long east-west dimensions (USA, Russia)

Flat-plane

• Appear to touch the globe at one point, such as North or South Pole.

• Useful for showing true direction for airplane pilots and ship navigators

Flat-plane shows true area size but distorts shape

Great Circle Route

• A straight line on a flat map is not the shortest distance

• Shortest route is called a great-circle route

• Pilots and ship captains use great-circle routes to help navigate The loxodrome is a line of constant heading, and

the great circle, although appearing longer than the loxodrome, is actually the shortest route between New York and London.

Geographic Coordinates

• Absolute location – is shown as (latitude, longitude) or (33N,118W)

which is the location of El Segundo

• Distance between Lines– If you divide the circumference of the earth

(approximately 25,000 miles) by 360 degrees, the distance on the earth's surface for each one degree of latitude or longitude is just over 69 miles, or 111 km

Even more precise

• Minutes and Seconds – For precision purposes, degrees of longitude

and latitude have been divided into minutes (') and seconds ("). There are 60 minutes in each degree. Each minute is divided into 60 seconds. Seconds can be further divided into tenths, hundredths, or even thousandths.

– El Segundo – (33.9’25” N,118.4’15” W)

Map Elements• Cartographers provide

basic map elements to help us translate the codes that contain information on maps

• Almost all maps have several common elements– Distance scale– Key– Directional indicator

Distance Scale

• Distance scales helps us determine real distance between two points on a map

• Distances measured and measurements used can vary

Keys

• A maps legend, or key, identifies the symbols representing cities, roads, and other features.

• They can use colors to represent different elevations, regions, and locations

Directional Indicators

• Shows which directions on a map are north, south, east, and west

• A compass rose has arrows that point to all four principal directions

Other Elements• Inset maps are used to

focus in on a small part of a larger map– They can focus in on a

specific area or focus on an area that is far away

– The map of the USA shows both contiguous and non contiguous states.

• Contiguous means connected or bordering

Special-purpose maps

• The two main types of maps we will be using are political and physical feature maps

• Other include– Climate and precipitation maps– Population and economic maps– Elevation profile and topographic maps

Climate and Precipitation Maps

Population and Economic Maps

Elevation maps and elevationprofiles help us better understandthe location of physical featuresfor an area

Elevation is the height above sea level

Topography - or elevation – is shown on contour maps

Climate Graphs and Population Pyramids

• Climate graphs show the average temperatures and precipitation in a place.

• Population pyramids show the percentage of males and females by age group in a country’s population– Help us understand population trends in countries– Name comes from pyramid shape– If not in shape of a pyramid, called age-structure

diagram