Earth Science 101Earth Science 101
Instructor : Pete Kozich
Introduction to Earth Science
Chapter 1
Earth ScienceEarth Science
Encompasses all sciences that seek to understand• Earth • Earth's neighbors in space
Earth is a dynamic body with many interacting parts and a long complex history
Earth ScienceEarth Science
Earth Science includes• Geology - literally the “study of Earth” • Oceanography – a study of the ocean,
youngest and newest study• Meteorology - the study of the atmosphere
and the processes that produce weather • Astronomy - the study of the universe, oldest
discipline
Geology-”study of Earth”Geology-”study of Earth”
• Physical geology: examines the material composing Earth and seeks to understand the many processes that operate beneath and upon the surface– Mountain building, volcanoes, erosion,
earthquakes
• Historical geology: understand the origin of Earth and the development of the planet through its 4.6 billion-year history
OceanographyOceanography
• Application of all sciences in a comprehensive interrelated study of oceans in all their aspects– Chemistry, physics, geology, and biology (old)– Oceanography is now becoming legitimate in
its own right via fluid dynamics and modeling.
• Study of composition and movement of seawater, coastal processes, seafloor topography and marine life.
MeteorologyMeteorology
• Study of the atmosphere and all the processes that produce weather and climate
• Involves the application of other sciences into an integrated study of the atmosphere
• Many disciplines within the whole such as synoptic, mesoscale, boundary layer, turbulence, and climatology
People and the environment People and the environment
Environment • Surrounds and influences organisms or
“small” entities• Physical environment encompasses water,
air, soil, and rock
People and the 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, fossil fuels, for example
People and the 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
• As population expands, the demand for resources expands too
Environmental problems• Local, regional, and global
People and the environment People and the environment
Environmental problems• Human-induced and accentuated
• Urban air pollution• Acid rain• Ozone depletion• Global warming (probable)
• Natural hazards • Earthquakes • Landslides
People and the environment People and the environment
Environmental problems• Natural hazards continued
• Floods• Hurricanes
• World population pressures• Increased rate of mineral and energy usage• US ~ 5% of world population and uses 25%
annual production of mineral and energy resources.
Scientific inquiry Scientific inquiry
Science assumes the natural world is • Consistent• Comprehensible through careful,
systematic study• Because of this, science is Predictable
Goal of science • To discover patterns in nature• To use the knowledge to predict
Scientific inquiry 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 that may eventually
become theories
Scientific inquiry Scientific inquiry Scientific knowledge is gained through
• Following systematic steps (Scientific Method)• Collecting facts• Developing a hypothesis • Conduct experiments • Re-examine the hypothesis and accept, modify, or reject
• Theories withstand examination • Totally unexpected occurrences a challenge-> is hypothesis correct
as is?
Scientific Law – a basic principle that describes nature’s behavior and is narrow in scope • Consistent with observations and measurements• Rarely discarded
Earth's “Spheres"Earth's “Spheres"Hydrosphere
• a dynamic mass of liquid that is always on the move from the oceans to the atmosphere precipitating back onto the land, then running back to the oceans again.
• Water makes the earth unique• Ocean – the most prominent feature of the
hydrosphere • 71% of Earth's surface • 97% of Earth's water • Average depth ~4000 m
• Also includes fresh water found in streams, lakes, and glaciers, as well as that found underground
Earth's “Spheres"Earth's “Spheres"
Atmosphere• Thin envelope of gases surrounding the earth able
to maintain life• Provides air to breathe, while protecting us from
the Sun’s intense heat and harmful radiation.• Without the atmosphere our planet may be lifeless
and resemble the surface of the moon.• Half of mass lies below 5.6 kilometers (3.5 miles)
• Compare to a radius of earth ~6400 km (4000 miles)
Earth's “Spheres"Earth's “Spheres"Biosphere
• Extends from the ocean floor upward into the atmosphere.
• Consists of parts of the hydrosphere, atmosphere and geosphere
• Includes all life • Organisms don’t just adapt to their
environment, countless interactions have allowed organisms to maintain and alter their environment.
Earth's “Spheres"Earth's “Spheres"
Geosphere• Extends from the surface to the center of the
planet (depth of 6400 km)• Largest of the four spheres• Based on compositional differences, it consists of:
• Dense core• Less dense mantle• Crust (very thin, light outer skin of the Earth)• Crust is not uniformly thick, but ranges from very thin
under the oceans to thickest where mountains are located.
Earth’s layered structureEarth’s layered structure
Earth system science 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 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 Earth system science
Feedback mechanisms • Negative-feedback mechanisms resist change and
stabilize the system (human sweating – cooling phenomena)
• Positive-feedback mechanisms enhance the system (you somewhat like art and take an art class; get more enthusiastic about it, take it as major; find much satisfaction and a job, make a living out of it)
Earth as a system • Consists of a nearly endless array of subsystems (e.g.
hydrologic cycle, rock cycle)
Earth system cyclesEarth system cycles
Figure 1.17
Earth system science 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 • Parts of the system are connected
• Change in one part can produce change in one or all other parts
• Complex, nonlinear, hard to predict