Chapter 1 Introduction to Earth

Geography Geography is derived from Greek for earth description Geography is derived from Greek for earth description Physical Geography is the study of the earth’s composition – it’s physical attributes, such as the surface: Physical Geography is the study of the earth’s composition – it’s physical attributes, such as the surface: Topography Topography Climate and soil Climate and soil Vegetation Vegetation Water bodies Water bodies Atmosphere Atmosphere

Physical vs. Cultural Geography 2 areas of study 2 areas of study Physical: things you can touch/see/experi encePhysical: things you can touch/see/experi ence Cultural/social: why things happen or are the way they areCultural/social: why things happen or are the way they are

4 Spheres Atmosphere – air Atmosphere – air Protective envelope around EarthProtective envelope around Earth Hydrosphere – water Hydrosphere – water Salt and fresh – necessary for lifeSalt and fresh – necessary for life Lithosphere – land Lithosphere – land Topmost layer of the mantleTopmost layer of the mantle Biosphere - all life Biosphere - all life Flora and faunaFlora and fauna

Fundamental Concepts Planet Earth - as a whole: It’s relation to solar system It’s relation to solar system Size and shape of Earth Size and shape of Earth Geographic grid – latitude & longitude Geographic grid – latitude & longitude Earth Sun relations Earth Sun relations Earth Moon relations Earth Moon relations

The Solar System Formation of the Solar System Formation of the Solar System Formed 4.5 to 5 billion years agoFormed 4.5 to 5 billion years ago 8 planets revolve around the Sun8 planets revolve around the Sun 4 terrestrial planets4 terrestrial planets 4 gas giants4 gas giants Earth is the third planetEarth is the third planet 6 © 2011 Pearson Education, Inc.

Solar System

The Planets Mercury Mercury Venus Venus Earth Earth Mars Mars Jupiter Jupiter Saturn Saturn Uranus Uranus Neptune Neptune Pluto – on again – off again Pluto – on again – off again

Ellipse vs. Circle 2 foci = ellipse 1 focus = circle

Earth’s Ellipse around Sun Shorter distance

23.5° Tilt

The Equator bisects the sphere of the Earth. It is The Equator bisects the sphere of the Earth. It is a great circle

Rotation of the Earth about its axis once every 24 hours is partially responsible for Coriolis effect tides jet lag day/night

The noon Sun is directly overhead the tropic of Cancer on The noon Sun is directly overhead the tropic of Cancer on June 21

Earth-Sun Relations

Size & shape of Earth Diameter = 8000 miles (radius = 4000) Diameter = 8000 miles (radius = 4000) Circumference = 25,000 miles Circumference = 25,000 miles Earth is slightly flattened at poles and wider at equator Earth is slightly flattened at poles and wider at equator Earth is approximately 4.6 billion yrs. old Earth is approximately 4.6 billion yrs. old

Latitude/Longitude Latitude and Longitude define site location on the surface of the earth Latitude and Longitude define site location on the surface of the earth Latitude is used to express distance north or south of the equator Latitude is used to express distance north or south of the equator Longitude shows east-west distance from the Greenwich 0° to the International Date 180° Longitude shows east-west distance from the Greenwich 0° to the International Date 180° Locations are given in degrees, minutes, seconds Locations are given in degrees, minutes, seconds For example: For example: Boston, MA: Lat 42.37N – Long 71.03WBoston, MA: Lat 42.37N – Long 71.03W Boston, MA: Lat 42° 22’ 11” - Long 71° 1’ 47”Boston, MA: Lat 42° 22’ 11” - Long 71° 1’ 47” Lawrence, MA: Lat 42.72N – Long 71.12WLawrence, MA: Lat 42.72N – Long 71.12W Lawrence, MA: Lat 42° 43’ 12” - Long 71° 7’ 12”Lawrence, MA: Lat 42° 43’ 12” - Long 71° 7’ 12”

Major lines of latitude

It becomes the next day. You are traveling west from San Francisco toward Seoul, when you cross the international date line at noon what happens?

Standard Time Zones Established 1884 Established time zones 24 time zones Each = 15° longitude Each = 15° longitude In international waters – strict In international waters – strict On land can vary – political or economic On land can vary – political or economic

Coriolis Deflection of a moving object, caused by the moving frame of reference on the spinning Earth As air warms, expands, and rises at the equator, it moves toward the pole, but instead of traveling in a straight path, the air is deflected eastward In the N. Hemisphere deflected to the right In the S. Hemisphere deflected to the left

Coriolis

Summary 34 Geography is the study of the distribution of physical and cultural attributes of Earth Geography is the study of the distribution of physical and cultural attributes of Earth Many sciences have branched off of geography Many sciences have branched off of geography The scientific method is important when doing scientific studies The scientific method is important when doing scientific studies Earth has four primary spheres: the atmosphere, the lithosphere, the hydrosphere, and the atmosphere Earth has four primary spheres: the atmosphere, the lithosphere, the hydrosphere, and the atmosphere The solar system formed 5 billion years ago and consists of 8 planets The solar system formed 5 billion years ago and consists of 8 planets © 2011 Pearson Education, Inc.

Summary 35 Earth is an imperfect sphere Earth is an imperfect sphere A latitude and longitude grid help identify locations on Earth’s surface A latitude and longitude grid help identify locations on Earth’s surface Earth rotates on its axis in 24 hours Earth rotates on its axis in 24 hours Earth revolves around the Sun in 365 ¼ days Earth revolves around the Sun in 365 ¼ days Tilt of Earth’s axis causes seasons Tilt of Earth’s axis causes seasons Equinoxes and solstices help identify when a seasonal transition occurs Equinoxes and solstices help identify when a seasonal transition occurs © 2011 Pearson Education, Inc.

Summary 36 Time zones were established to have a uniform global time system Time zones were established to have a uniform global time system Daylight-saving time was devised to conserve energy by adding an hour of daylight Daylight-saving time was devised to conserve energy by adding an hour of daylight © 2011 Pearson Education, Inc.