Introduction to Earth Science Earth Science Chapter 1 Mr. Willis Earth and Space Science WH.
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Transcript of Introduction to Earth Science Earth Science Chapter 1 Mr. Willis Earth and Space Science WH.
Introduction to Earth ScienceEarth Science
Chapter 1
Mr. Willis Earth and Space Science WH
Encompasses all sciences that seek to understand Earth Earth’s neighbors in space
Earth Science includes Geology – literally the “study of Earth” Physical Materials composing the Earth Historical study of the origin and development of
the Earth Oceanography – a study of the ocean Meteorology – the study of the atmosphere and the
processes that produce weather Astronomy – the study of the universe
Earth Science
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
Population Population of the planet is growing rapidly Rate of mineral and energy usage has climbed
more rapidly than the overall growth of population
Current populations US 314,340,477 (US Census Bureau) World 7,038,328,935 (US Census Bureau) World Leader:
China
People and the environment
Figure 1.3 in text
Figure 1.2 in text
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
Figure 1.6 in text
Figure 1.1B in text
Environmental problems
Local, regional, and global Human-induced and accentuated
Urban air pollution Acid rain Ozone depletion Global warming
* Natural hazards Earthquakes Landslides Floods Hurricanes World population pressures
People and the environment
Science assumes the natural world is Consistent Predictable
Not always the case
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
Scientific inquiry
In Earth and Space Science observations are made from smallest objects (atoms) to the largest (stars) Types of scale within Earth and Space Science Mohs Scale of Hardness
Minerals Hardness Richter Scale
Earthquakes Geologic Time Scale
Age of Earth Fujita Scale
Tornados HR Diagram
Stars
Scaling in Earth Science
Figure 1.6 in text
Figure 1.7 in text
Humans and the Environment Paper
Is the recent increase in human fatalities/property damage globally from natural disasters (i.e. hurricanes, floods, tornados, etc.) a function of the global warming/climate change or human population growth/encroachment on areas where man was not intended to habitate.-Using at least four sources, develop a thesis that clearly states your position on the issue and write a 4-5pgs persuasive paper on this topic.-Be sure to include the concepts of the Earth System in your discussion.
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
Early evolution of Earth
The Nebular hypothesis
Figure 1.8 in text
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
Early evolution of Earth
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) Accounts for all gases in and around the Earth.
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 – solid material at the surface Mantle- 82% of the earth’s volume Core – Inner (radius ~1216km/754mi) Outer
(2260km/1400mi) Divisions of the outer portion are based on how
materials behave Lithosphere – rigid outer layer (avg. 100km in
thickness) Asthenosphere – weak sphere Divisions of Earth’s surface – continents and ocean
basins
Earth’s “Spheres”
Earth’s layered structure
Figure1.14 in text
A closer look at the geosphere
Figure 1.16 in text
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 On a macro-scale
Hydrosphere, geosphere, biosphere, and atmosphere
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 As the dominant species on the planet, our
geologic-footprint is also the greatest.
Earth system science
End of Chapter 1