Earth Science, 13e

Tarbuck & Lutgens

Introduction to Earth ScienceEarth Science, 13eChapter 1

Stanley C. Hatfield Southwestern Illinois College

Warm up:

List your 4 vocabulary words with definitions.

Earth Science Encompasses all sciences that seek to

understand Earth Earth’s neighbors in space

Earth Science includes Geology – literally the “study of Earth” Oceanography – a study of the ocean

Earth Science Earth Science includes

Meteorology – the study of the atmosphere and the processes that produce weather

Astronomy – the study of the universe

People and the environment Environment

Surrounds and influences organisms Physical environment encompasses

water, air, soil, and rock Term “environmental” is usually reserved

for those aspects that focus on the relationships between people and the natural environment

People and the environment Resources

An important focus of the Earth sciences Includes water, soil, minerals, and energy Two broad categories

Renewable – can be replenished (examples include plants and energy from water and wind)

Nonrenewable – metals (examples include metals and fuels)

People and the environment Population

Population of the planet is growing rapidly Rate of mineral and energy usage has

climbed more rapidly than the overall growth of population

Environmental problems Local, regional, and global

People and the environment Environmental problems

Human-induced and accentuated Urban air pollution Acid rain Ozone depletion Global warming

Natural hazards Earthquakes Landslides

People and the environment Environmental problems

Natural hazards continued Floods Hurricanes

World population pressures

Scientific inquiry Science assumes the natural world is

Consistent Predictable

Goal of science To discover patterns in nature To use the knowledge to predict

Scientific inquiry An idea can become a

Hypothesis (tentative or untested explanation)

Theory (tested and confirmed hypothesis) Paradigm (a theory that explains a large

number of interrelated aspects of the natural world)

Scientific method Gather facts through observation Formulate hypotheses and theories

Scientific inquiry Scientific knowledge is gained through

Following systematic steps Collecting facts Developing a hypothesis Conduct experiments Re-examine the hypothesis and accept,

modify, or reject Theories that withstand examination Totally unexpected occurrences

Early evolution of Earth Origin of Earth

Most researchers believe that Earth and the other planets formed at essentially the same time

Nebular hypothesis Solar system evolved from an enormous

rotating cloud called the solar nebula Nebula was composed mostly of hydrogen

and helium

Early evolution of Earth Origin of Earth

Nebular hypothesis continued About 5 billion years ago the nebula began

to contract Assumes a flat, disk shape with the

protosun (pre-Sun) at the center Inner planets begin to form from metallic

and rocky clumps Larger outer planets began forming from

fragments with a high percentage of ices

The Nebular hypothesis

Early evolution of Earth Formation of Earth’s layered structure As Earth formed, the decay of radioactive elements

and heat from high-velocity impacts caused the temperature to increase Iron and nickel began to melt and sink toward the center Lighter rocky components floated outward, toward the

surface Gaseous material escaped from Earth’s interior to

produce the primitive atmosphere

Earth’s “Spheres” Hydrosphere

Ocean – the most prominent feature of the hydrosphere Nearly 71 percent of Earth’s surface About 97 percent of Earth’s water

Also includes fresh water found in streams, lakes, and glaciers, as well as that found underground

Earth’s “Spheres” Atmosphere Thin, tenuous blanket of air One half lies below 5.6 kilometers

(3.5 miles) Biosphere

Includes all life Concentrated near the surface in a zone that extends

from the ocean floor upward for several kilometers into the atmosphere

Earth’s “Spheres” Solid Earth

Based on compositional differences, it consists of the crust, mantle, and core

Divisions of the outer portion are based on how materials behave Lithosphere – rigid outer layer Divisions of Earth’s surface – continents and

ocean basins

Earth’s layered structure

Earth system science Earth is a dynamic body with many

separate but highly interacting parts or spheres

Earth system science studies Earth as a system composed of numerous parts, or subsystems

System – any size group of interacting parts that form a complex whole

Earth system science System

Closed systems are self-contained (e.g., an automobile cooling system)

Open systems – both energy and matter flow into and out of the system (e.g., a river system)

Earth system science Feedback mechanisms

Negative-feedback mechanisms resist change and stabilize the system

Positive-feedback mechanisms enhance the system

Earth as a system Consists of a nearly endless array of

subsystems (e.g., hydrologic cycle, rock cycle)

Earth system science Earth as a system

Sources of energy Sun – drives external processes such as

weather, ocean circulation and erosional processes

Earth’s interior – drives internal processes including volcanoes, earthquakes and mountain building

Humans are part of the Earth system

Create a visual that includes and incorporates:the nebular hypothesis and the Earth’s Spheres

Describe the steps of the Nebular Hypothesis

Describe each sphere

Warm up 8/28/13 Finish your poster! Name the four spheres Explain each sphere

Warm up Name the four spheres Explain each sphere Get out your scavenger hunt