Chapter 1: Introduction to

Earth Science

1.1 What is Earth Science

� Earth science is the name for the group of sciences that deals with Earth and its neighbors in space.

� Includes:

– Geology

– Oceanography

– Meteorology

– Astronomy

Geology� Geology means “study of earth.”

� Consists of physical geology and historical geology

Oceanography� Oceanographers study the composition

and movements of seawater, as well as coastal processes, seafloor topography, and marine life.

Meteorology� The study of the atmosphere and the

processes that produce weather and climate.

Astronomy� The study of the universe.

Formation of Earth� The nebular hypothesis suggests that

the bodies of our solar system evolved from an enormous rotating cloud called the solar nebula. It was made up mostly of hydrogen and helium, with a small percentage of heavier elements.

� KNOW pg. 4—Figure 3!!

A

C

D

E

B

� The inner planets were not able to hold onto the lighter gasses (such as hydrogen and helium).

� Earth, Mars, and Venus kept some water and carbon dioxide (because they are heavier compounds).

� The denser elements sank towards the center of Earth (iron/nickel).

� Gasses escaped from volcanoes forming the atmosphere and oceans.

1.2 A View of Earth

� Earth consists of four major spheres:

� Hydrosphere

� Atmosphere

� Geosphere

� Biosphere

Hydrosphere

� All of the water on the Earth makes up the hydrosphere

� The oceans make up 97 percent of the water on the Earth.

� Freshwater is contained in the groundwater, streams, lakes, and glaciers.

Atmosphere

� Provides the air we breath

� Protects us from the sun’s heat and radiation

� Provides for weather and climate

� Without it, the Earth’s surface would resemble the moon.

Geosphere

� Divided into three main parts:� Core

� Mantle

� Crust

� Subparts� Inner Core, Outer Core, Lower Mantle,

Upper Mantle, Asthenosphere, Lithosphere, Oceanic Crust, and Continental Crust

Earth’s Layered Structure

Know the Layers

of the Earth!!

Biosphere� Includes all life on Earth

� Extends from the ocean floor up to several kilometers into the atmosphere

Plate Tectonics� We will cover an entire unit on this

� Know the two forces:

� Destructive Forces—wear away high

points and flatten out the surface

� EX: weathering and erosion

� Constructive Forces—build up the surface

by raising the land and depositing lava

� EX: mountain building and volcanism

Plate Tectonics

� The theory provides geologists with a model to explain how earthquakes and volcanic eruptions occur and how continents move.

� Earth’s lithosphere is broken into several individual sections called plates

� Look at Pg. 9

Skip 1.3 For Now

1.4 Earth System Science

� Earth is a system made up of numerous interacting parts, or subsystems.

� A system can be any size group of interacting parts that form a complex whole.

Earth as a System� Earth has two energy sources: The

sun, and the earth’s interior.

� When one part of the earth system changes, it can affect the other systems.

People and The Environment� Environment refers to everything that

surrounds and influences an organism.

� Resources are an important focus in Earth Science

� Resources are divided into two categories: Renewable and Nonrenewable.

Population

Environmental Problems� Significant threats to the environment

include air pollution, acid rain, ozone depletion, and global warming (and many more).

1.5 What is Scientific Inquiry?

� The process of gathering facts through observations and formulating scientific hypotheses and theories is called the scientific method.

� Generally, there are four steps:

� 1. Collection of scientific facts through observation and measurement.

� 2. Development of one or more working hypotheses or models to explain these facts.

� 3. Development of observations and experiments to test the hypotheses

� 4. Acceptance, modification, or rejection of the hypotheses based on extensive testing.