Earth ScienceEarth Science

Chapter 1Chapter 1

ProloguePrologue

The Local EnvironmentThe Local Environment

• Observation– Use of one or more of the senses to learn

something about the environment• Instruments improve our ability to make

observations.

• Inference– Interpretation of observations

• Classification– Grouping of observations

Properties of the EnvironmentProperties of the Environment

• Measurement– Describes observations using numbers– Two common systems are metric (SI) and

English.– Metric System

Kilo Hecto Deca Meter Deci Centi Milli

1000 100 10 1 .1 .01 .001

DensityDensity

• Density– Quantity of matter in a given space– Density = Mass

Volume• Mass is the amount matter in an object

–Weight is the pull of gravity on an object• Volume is the amount of space an object

takes up

M

D V

DensityDensity

• Each pure substance has a particular density.• The density of most materials increases as they

change from gas to liquid to solid.• Water is an exception to this “rule”.

– The maximum density of water occurs in the liquid state at 4 degrees Celsius.

• Change in density of a gas– Increased temperature = decreased density– Increased pressure = increased density

The Nature of ChangeThe Nature of Change

• Characteristics of change– Event

• Any change or series of changes• Events can be instantaneous like lightning

or gradual like the wearing away of mountains.

• Earth scientists are interested in describing the events of change and discovering the causes.

The Nature of ChangeThe Nature of Change

– Rate of change• How long it takes for a change to occur• Rate of change = change in value

time– Graphs

• Graphing change gives you a picture of what is happening.

• A graph shows you how one factor is changing with respect to another.

The Nature of ChangeThe Nature of Change

020406080

20 40 60 80

Direct

020406080

20 40 60 80

Indirect

020406080

Cyclic

020406080

20 40 60 80

Static

The Nature of ChangeThe Nature of Change

• Cyclic changes– Events that repeat themselves regularly– Examples

• Rock cycle, water cycle, seasons, moon phases

• Dynamic equilibrium– When there is a balance between changes

• Interface– The boundary between different systems