1. Chapter 1 Introduction to Earth Science

2. What is Earth Science? 1.1
What forces produced the mountains shown on page 1?
Why does our daily weather change?
Is our climate changing?
How old is Earth?
How is Earth related to other planets in the solar system?
What causes ocean tides?
What was the Ice Age like?
Will there be another?

3. Overview of Earth Science 1.1
Deals with Earth and its neighbors in space
Geology “study of Earth”
2 broad areas
Physical – examination of materials that make up Earth & explain possible process that shape our planet
Earthquakes, mountains, volcanoes, erosion, rocks, minerals
Historical – understand Earth’s long history
est. time line

4. Overview of Earth Science Continued… 1.1
Oceanography – study coastal process, seafloor topography, marine life, and composition and movement of seawater
incorporates: chemistry, physics, geology, & bio
Meteorology - study of the atmosphere, weather, and climate
Astronomy – study of the universe
all objects in space, including earth

5. Formation of Earth 1.1 1 of 9 (or 8) planets Solar system = orderly
Formed during same span as other planets and from the same material as the sun
Nebular Hypothesis – bodies of solar system evolved from enormous rotating could, the solar nebula
made mostly of H & He

7. Nebular Hypothesis 1.1 Look at Picture on Page 4
What do all the stages of this hypothesis have in common?
What was the first stage in the development of our solar system?
While Earth formed, denser materials sank to Earth’s core while less dense materials escaped to the atmosphere

9. Layers Form on Earth 1.1 Earth Formed
Radioactive element breakdown (decay)
Heat released (from all the colliding particles)
Melting of the interior
Denser element (iron and nickel) sink to center
Lighter/rocky float outward
Still believe to occur
Atmosphere forms from gases escaping

10. A View of Earth 1.2 Earth’s Major Spheres 3 major PHYSICAL Environment
Hydrosphere – water portion
Evaporates  falls back as precipitation  runs back to rivers/oceans/etc
Oceans = 97% of water on Earth
3% = groundwater, streams, lakes, and glaciers
Important b/c the sustain life and help create land forms

11. Atmosphere Geosphere Gaseous envelop 100 km above earth
90% just within 16 km of earth
Provides air we breath
protects
Geosphere
Not uniform
Core – heavy dense inner core
Mantle
Crust – lighter – not uniform
Thinnest beneath the ocean
Thickest beneath continents
Lithosphere – uppermost mantle
Asthenosphere – below lithosphere - molten rock

13. Biosphere – all of life on earth
4th major sphere
Biosphere – all of life on earth
Ocean floor and upward for several km into the atmosphere

14. Plate Tectonics 1.2
Grand Canyon, the Rocky Mountains, and the Appalachian Mountains did not exist a billion years ago
Destructive forces – weathering, erosion (wear away land)
Constructive Forces – mountain building and volcanism (raising the land)
Revolution – learning more about Earth
Idea that continents moved the face of the Earth = PLATE TECTONICTS
Earth broken at lithosphere into plates
Motion caused from uneven heating of earth’s surface = earthquakes, volcanic activity, rocks into mountains

16. Representing Earth’s Surface 1.3
Global Grid
Latitude (fatitude) – distance N or S of the equator (0o latitude) – lines run E and W
Longitude – Distance E or W of the prime meridian (0o longitude) – lines run N and S
Earth is 360 degrees around
Equator divides Earth in 2 hemispheres
Northern and southern
Prime Meridian divides earth in 2 hemispheres
Eastern and western

17. Globes 1.3 Shapes, sizes of islands, continents, and bodies of water
Found by exploring
Best represented thru a globe
Earth is round

18. Maps and Mapping 1.3 Flat representation of Earth’s surface
Can not be accurately represented
Too small, big, out of place
The Mercator Projection
Gerardus Mercator made map in 1569 to help sailors navigate
Lines of longitude are parallel (compare to globe)
Makes grid rectangular
Bonus: showed directions accurately
Negative: sizes and distances distorted (esp around poles)

19. The Mercator Projection

20. Different Projection Maps for Different Purposes 1.3
Best project determined by use
Robinson Projection – widely used
Bonus: show most distances, sizes, and shapes accurately
Negative: distortions around the edges
Conic Projection – wrap a cone of paper around a globe at line of latitude, trace
Almost no distortion at line of latitude
High distortion away from latitude line
Accuracy great over small area (used for maps)
Gnonomic Projection
Place piece of paper on globe so it touches since point
Distance and direction distorted
Useful to sailors to show shortest distance between 2 oints

22. Topographic Maps 1.3 Represent Earth’s 3-D surface in 2-D
Show elevation by contour lines
Also can show water, roads, gov and public buildings, political boundaries, and places names
Contour Lines – every position along a single contour line is the same elevation
Every 5th line is bolded = index contour
Closer together line = steep slope
Farther apart lines = gentle slope
Never touch or intersect
Depression = circular contours that have hachure marks – small lines on circle that point to the center

23. Scale of Topographic Maps 1.3
Determine distances on the map and relate them to the real world
Certain distance on the map is drawn to equal a certain distance on the surface
1:24,000 = ratio
Has no units
1 unit on map is equal to 24,000 units on the ground

24. Geologic Maps 1.3 Shows type and age of the rocks exposed
Each rock formation assigned a color and sometimes a pattern

25. Advance Technology 1.3
Gives us the ability to more precisely analyze Earth’s physical properties
Use satellites and computers
Remote sensing – process of collecting data about Earth from a distance

26. Technology and Earth Science 1.3
Weather Satellites – monitor temp, humidity, & clouds
Navigation Satellite – assists ships and submarines
Landsat Satellite – Data on Earth’s landmasses, coastal boundaries, and coral reefs  complete 14 orbits per day
GPS - Combines satellite with computer technology providing latitude, longitude, and altitude
Very Long Baseline Interferometry – measures the geosphere – study tectonic plates

27. Earth System Science 1.4
Look at earth as a system made up of numerous interacting parts
Tries to study all branches of science
What is a System?
Any size group of interacting parts that form a complex whole.
Closed System – no matter enters or leaves the system; energy moves freely
Open System – both energy and matter flow into and out of the system
Most natural systems

28. Earth as a System 1.4 Earth powered by energy from 2 sources
Sun – drives external processes (weather, climate, ocean circulation, erosion processes)
Earth’s interior – from radioactive element and from time Earth formed
power internal process = volcanoes, earthquakes, and mountains
Change in one system affects the other
Volcano erupts  lava flow block nearby valley  influence drainage system  ash influences solar energy = drop in temp.
Our actions produce changes in all parts of Earth’s system

29. People and the Environment 1.4
Environment – everything that surround and influences an organism
Biological or social
Nonliving = physical environment = air, water, soil, rock, temp, humidity, sunlight
Environmental Science – focus on relationships between people and the natural environment

30. Resources 1.4
Water and soil, metallic and nonmetallic minerals, and energy
Foundation of modern civilization
RENEWABLE resource – can be replenished in a short period of time
Plants and animal food, natural fibers, lumber, paper, water, wind, and the sun
NONRENEWABLE – process to create sources takes millions of years
Iron, aluminum, copper, oil, natural gas, coal

31. Population 1.4 Growing rapidly
Population increases, demand for resources increases
Yet, energy resources do not increase
Leads to many questions
How long will the remaining supplies of basic resources last?
How long can we sustain the rising standard of living in today's industrialized countries?
How much environmental deterioration are we willing to accept to obtain basic resources?
Can alternatives be found?

32. Environmental Problems 1.4
Air pollution
Acid rain
Ozone depletion
Global warming
Loss of fertile soils to erosion
Toxic waste
Depletion of water resources
Natural hazards: earthquakes, landslides, floods, hurricanes, drought
Knowledge about Earth and how it works is necessary to our survival and well being

33. What is Scientific Inquiry? 1.5
Science based on 2 assumptions:
Natural world behaves in a consistent, predictable manner
Careful, systematic study can explain the natural world’s behavior
Basics steps to the scientific method
Collect data thru observation and measurement
(Question)
Hypothesis (1 or more working hypothesis)
Test and Analyze
Conclusion = acceptance, modification, or rejection of hypothesis

34. Scientific Inquiry 1.5 Theory
Made after hypothesis has been tested extensively and competing hypothesis eliminated
well tested and widely accepted by scientific community
EXPLAINS observable facts