Visualizing Earth Science

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

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

3. Science and the Scientific Method • 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. 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 The Earth System Principal subsystems of the Earth System

9. Feedback Mechanisms Feedback Mechanisms System – Environment interaction cycles that change open systems Positive feedback Enhance change in systems Negative feedback Reduce change in systems • 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

10. The Earth in Space 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 The Solar System

11. The Earth in Space The Solar System

12. The Earth in Space 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 The Terrestrial Planets

13. 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 The Layers of the Earth Layers by composition

14. The Layers of the Earth Layers by composition

15. 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 The Layers of the Earth Layers by rock strength

16. The Layers of the Earth Layers by rock strength

17. The unique Earth 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 The life supporting planet

18. The unique Earth 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 The geologically active planet

19. The unique Earth

20. The unique Earth 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 The geologically active planet

21. Humans and Earth 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 Population growth

22. Humans and Earth 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 Resource management

23. 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 Humans and Earth

24. Resources and Modern Society Humans and Earth

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. 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 Chapter Summary