1. Visualizing Earth Science
By Z. Merali and B. F. Skinner
Chapter 1 – Introduction to Earth Science

2. Chapter Overview
Earth Science
The Earth in Space
Humans and Earth

3. Science and the Scientific Method
Systematic approach to studying natural processes
Make observations
Formulate a hypothesis
Conduct tests of the hypothesis
Evaluate and generalize
Earth Science
The scientific study of aspects of Earth

4. Science and the Scientific Method

5. Systems The Systems approach
Deconstruct Universe into interconnected elements or units
Identify processes connecting and boundaries separating systems

6. Types of Systems
Systems classified according to boundary interactions with the environment
Isolated: No energy or matter is exchanged
Closed: energy is exchanged but not matter.
Open: energy and matter can be exchanged with environment

7. The Earth System A(n almost) closed system Earth System Science
Treat Earth Science as a single field of study
Emphasis on studying interconnections between Earth subsystems

8. Principal subsystems of the Earth System
Four principal open subsystems or “spheres”
The lithosphere
The hydrosphere
The atmosphere
The biosphere
Each interacts with the others
Most intensely in the life zone

9. Feedback Mechanisms How feedback works
System interacts with environment
Interaction produces change in the system
System responds to the change
System response “feeds back” or affects the change in the system
Feedback Mechanisms
System – Environment interaction cycles that change open systems
Positive feedback
Enhance change in systems
Negative feedback
Reduce change in systems

10. The Earth in Space The Solar System The Earth – Our planet
One of eight large, spherical bodies orbiting the Sun
Third from the sun
A relatively smaller, denser body
The inner planets: Mercury, Venus , Earth and Mars are the terrestrial planets
Larger, less dense planets: Jupiter, Saturn, Uranus and Neptune are jovian planets
The Earth is uniquely suitable for sustaining life

11. The Earth in Space
The Solar System

12. The Earth in Space The Terrestrial Planets
General characteristics of terrestrial planets
Similar densities – a little greater than common rocks
Dense metallic core surrounded by less dense rocky layer
A result of partial melting of planets in their early history
Thin atmospheres
Warmer temperatures

13. The Layers of the Earth Layers by composition
A dense two-layer metallic core
A solid inner core
A liquid outer core – responsible for the Earth’s magnetic field
Composed of iron and nickel
A less dense rocky middle layer – the mantle
A thin brittle rocky outer layer – the crust

14. The Layers of the Earth
Layers by composition

15. The Layers of the Earth Layers by rock strength
Rocky layers (mantle and crust) have distinct structures based on rock strength
The lithosphere
The crust and upper mantle
Strong but brittle cool rock
The asthenosphere
Easily deformed rock
Higher temperature and increased pressure
The mesosphere
Very high temperature and intense pressure
Strong rock

16. The Layers of the Earth
Layers by rock strength

17. The unique Earth The life supporting planet
Presence of Oxygen in the atmosphere
Presence of Water
Hydrosphere contains solid, liquid and gaseous water
The Biosphere (System)
Contains all life on Earth
Interacts with surroundings and with itself
Changes and shapes its own environment
Soil – layer of loose debris formed by weathering

18. The unique Earth The geologically active planet Tectonic activity
The lithosphere is broken into large slabs or plates
There is large scale movement of plates
Plate tectonics continually reshapes the surface of the Earth

19. The unique Earth

20. The unique Earth The geologically active planet
Lithosphere shaped by tectonics
Older lighter plates float higher over the asthenosphere
Form the continents
Composed mainly of granitic rock
Newer dense plates sink deeper into the asthenosphere
Form the oceans
Composed of basaltic rock

21. Humans and Earth Population growth
Growth in human population demands increasing resources
Population growth and its effects on food and resources
Debated among policy makers and academia
Needs a response to sustain present resource levels

22. Humans and Earth Resource management
Natural resources are often scarce
Renewable resources
Can be replaced through natural processes
The timescale of replacement is shorter than the timescale of use
Nonrenewable resources
Cannot be replaced within the timescale of use

23. Resources and Modern Society
Humans and Earth
Resources and Modern Society
Use of resources in the US and the most industrialized economies
- Disproportionately large in comparison with the world
- Energy resources
Used at rate over four times the world average
Dependence on external imports to sustain levels of use

24. Resources and Modern Society
Humans and Earth
Resources and Modern Society

25. Motivation for the study of Earth Science
Understanding the Earth system
Provides an appreciation of the Earth System as a closed system
All material resources are limited
Sustaining resources requires
understanding processes and
understanding time-scales
Provides an understanding of
Geological features
Phenomena and
Natural hazards

26. Motivation for the study of Earth Science
What ?

27. Chapter Summary Earth Science and Earth Scientists
Use the scientific method
Study the Earth as a closed System
Study Earth System mechanisms and processes
Earth’s place in the Universe
Earth is a planetary body in the solar system
Earth is unique in many aspects
It sustains life
It is geologically active
Human interaction with the Earth
Earth’s resources are limited
Resources management must be understood and applied