EARTH SCIENCE 6 th Grade

The Earth System  System: a group of parts that work together as a whole.  Energy allows Earth to work as a system as it moves matter through its parts.

The Earth System

The Atmosphere  The relatively thin envelope of gases that forms Earth’s outermost layer.  Mostly made of nitrogen and oxygen.

The Geosphere  The geographic makeup of the Earth.  Three main parts: a metal core, a solid middle layer, and a rocky outer layer.

The Hydrosphere  Contains all of Earth’s water.  About ¾ of Earth’s surface is covered, but more water can be found underground and in different parts of the water cycle.

The Biosphere  The parts of Earth that contain living organisms.

Making Connections  Brainstorm a way 2 of the systems interact with each other and write it in your notebook. You are going to share this idea with a partner in 1 minute.  With your partner, come up with a way that 3 of the system interact. You will share your idea with another pair in 1 minute.

Making Connections  As a group of 4, come up with a way that all 4 parts of the Earth’s system interact. We will share our ideas with the class in 2 minutes.

EARTH’S SURFACE Chapter 1: Mapping Earth’s Surface Lesson 1: Exploring Earth’s Surface

What is Topography?  Topography: the shape of the land; an area’s elevation, relief, and landforms.  elevation: the height above sea level of a point on Earth’s surface.  Relief: the difference in elevation between the highest and lowest parts of an area.  Landforms: feature formed by the processes that shape Earth’s surface (hills, valleys, etc.).

Types of Landforms  Plain: landform made of nearly flat or gently sloped land.  A coastal plain is along the seacoast; an interior plain is away from the coast.  The Great Plains extend from Texas into Canada.

Types of Landforms

 Mountain: landform with high elevation and high relief.  A mountain range is a group of mountains that are closely related in shape, structure, area, and age.  A mountain system is made of different mountain ranges.  A mountain belt is a long, connected chain of ranges and systems.

Types of Landforms

 Plateau: landform with high elevation and a level surface.

Landform Regions  Landform region: a large area of land where the topography is made up mainly of one type of landform.  An upland is a region of hilly topography; a lowland is a region of plains with low elevation.

EARTH’S SURFACE Chapter 1: Mapping Earth’s Surface Lesson 2: Models of Earth

Maps and Globes  Globe: a sphere that represents Earth’s entire surface.  Map: flat model of all or part of Earth’s surface as seen from above.  Both are drawn to scale and use symbols.  Maps have projections to show the curved surface of Earth.

Maps and Globes  Globe: a sphere that represents Earth’s entire surface.  Map: flat model of all or part of Earth’s surface as seen from above.  Both are drawn to scale and use symbols.  Maps have projections to show the curved surface of Earth.

Map Projections  Map projection: framework of lines that helps to transfer points on Earth’s 3-D surface onto a flat map.  A Mercator projection is based on a cylinder with grid lines; the size and shape of landmasses becomes more distorted toward the poles.

Symbols and Keys  Symbols: shapes or pictures that stand for features on Earth’s surface.  Physical features (ex: river) and man-made features (ex: highway).  Key: a list of all of the symbols used on the map.  Sometimes called a legend  Compass rose: shows direction

Scale  Scale: relates distance on a map to distance on Earth’s surface.  Three different ways to give scale:  Ratio scale: 1 : 500  Bar scale  Equivalent scale: 1 cm = 500 m

Degrees  Distances on Earth are measured in degrees from the equator and the prime meridian.  A degree is 1/360 of the distance around a circle.  They can be divided into minutes and seconds for more precise measurement.

The Equator  The equator is an imaginary line that goes around the Earth and divides it into Northern and Southern hemispheres.  Hemisphere: one half of a sphere (Earth)

The Prime Meridian  The Prime Meridian is an imaginary line that goes from the North Pole to the South Pole; divides the Earth into Eastern and Western hemispheres.  Passes through Greenwich, England.

Latitude  Latitude: distance in degrees north and south of the equator.  The equator is 0 degrees; the North Pole is 90 degrees N and the South Pole is 90 degrees S.  Each degree of latitude = approx. 111 km.

Longitude  Longitude: distance in degrees east and west of the prime meridian.  The prime meridian is 0 degrees; the lines of longitude go to the east and west to 180 degrees.  Each degree of longitude at the equator = approx. 111 km.

EARTH’S SURFACE Chapter 1: Mapping Earth’s Surface Lesson 3: Mapping Technology

Making Maps  Surveying: finding distances and elevations using instruments and geometry.  Pictures from airplanes used to be used to create maps, now computers can digitally form them.  Digitizing: process of changing the location of map points into numbers.

Aerial Photographs  Aerial photographs: taken by cameras in airplanes; show man-made and nature-made landforms.  Can show how land changes over time.

Satellite Imaging  Satellite images: taken from satellites that orbit Earth; images are made of pixels that are translated into photos.  Different colored pixels represent different heights of elevation.

GPS  Global Positioning System (GPS): satellite images can detect location and motion of objects.  3 satellites are used to detect your location; a 4 th satellite is used to detect your elevation.  Global Information System (GIS): system of hardware/software to create interactive maps.

EARTH’S SURFACE Chapter 1: Mapping Earth’s Surface Lesson 4: Topographic Maps

Topographic Maps  Topographic map: map showing the surface features of an area.

Contour Lines  Mapmakers use contour lines to show elevation, relief, and slope on maps.  Contour lines: connect points of equal elevation.  Contour interval: change in elevation from one contour line to the next.  Index contour: every fifth contour line; darker than the rest.

Reading Topographic Maps  Step 1: become familiar with the map’s scale and contour lines.  Step 2: determine the contour interval.  Step 3: begin at a labeled index contour and count lines up or down to a certain feature.

Reading Topographic Maps  Closely spaced lines = steep slopes  Widely spaced lines = flatter areas.  Closed contour lines/loops = hilltop  V-shaped contour lines downhill = ridge line  V-shaped contour lines uphill = valley