Transcript Earth Science

Earth Science
Sec. 1.1
Introduction to Earth Science
and systems
Systems
and
Cycles
and
Spheres
“Oh my”
Questions Earth Science Tries to
Answer?
• What forces produce mountains?
• Why is our daily weather so terrible?
• How old is our earth and how is it related to
the other planets in the solar system?
• When will be the next big earthquake?
• What the caused of the Ice age and are we
done with them?
• Can a successful well be located at this site?
Who do you think tries to answer these
questions about Earth Science?
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Will Mt. St. Helens erupt soon?
How can we better forecast hurricanes?
Will a meteor hit Earth?
When will the next big earthquake hit?
Are the melting icecaps affecting the ocean
currents?
• Can an oil well be located at this site?
Answers
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Volcanologist
Meteorologist
Astronomer
Seismologist
Oceanographer
Petroleum Geologist
What exactly is Earth Science?
• All sciences that
collectively seek to
understand Earth and its
neighbors in Space.
– Including
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Geology
Oceanography
Meteorology
Astronomy
Geology
• Means “study of Earth”
• Types
– Physical
• Examines materials composing the earth
• Process that operate beneath and upon its
surfaces
– Historical
• Understand the origin of the earth
• Understand the development of the planet
Oceanography
• Integrates Chemistry, physics, geology
and Biology
• Studies:
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Composition and movements of seawater
Coastal processes
Seafloor Topography
Marine Life
Meteorology
• Not the study of meteors!
• Study of:
• Layers of the atmosphere
– Processes that produce
weather and climate
Astronomy
• Not about your horoscope!
• Study of the universe.
• Not specifically covered in this
class.
• We have a separate course devoted
solely to this topic.
The Earth as a “System”
• Everyday systems:
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Car’s cooling system
Transportation system
Political system
Weather system
Solar system
• Definition
– Any size group of interacting parts that form a complex
whole unit
Earth Science
• Newer Concept (turn of the century)
• Study of ALL the different disciplines put
together
• Interconnectedness, interdependence
Types of Systems
Closed system
and
Open System
Closed system
• Self contained. MATTER stays in.
• Energy moves freely in and out
• Example:
Open System
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Matter and energy move in and out freely
More complicated
Very common in nature
Example: river
Open or closed system?
Open or closed system?
Type of System?
Type of System?
Type of System?
Type of System?
Type of system?
Earth: open or closed system?
Sec. 1.2 Earth’s Four Spheres
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Hydrosphere
Atmosphere
Solid Earth
Biosphere
The Earth’s spheres are all connected
Hydrosphere
• All the water
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Lakes, rivers
Oceans
Glaciers
Aquifers
Of the hydrosphere….
• Oceans (salt water)
97.5%
• Fresh water (drinkable)
– Frozen /ice (glaciers)
– Ground water (aquifers)
– Rivers / lakes
– Atmosphere
2.5%
Atmosphere
• Gaseous envelope around earth
– Half of it below 3.5 miles (5.6 meters)
– 90% occurs within 10 miles (16 km) of the surface
Purpose
– Light (Radiation) protection
– Energy exchange
– Breathing
Geosphere
• Also known as solid* Earth
• 3 basic Parts
- Core
• Dense center
- Mantle
- Less dense solid/liquid*
– Crust
• Thin outer crust
Earths’ crust or lithosphere consists
of..
• Continents
– Ave. elevation 2750 feet above sea level (840 m)
• Ocean floor
– Ave. depth 12,500 feet (3800 m)
Continents stand nearly 3 miles above the sea
floor (4640 m)
Biosphere
• All living things on the planet.
• The other 3 spheres made biosphere possible!
• Examples:
– everything from single-cell protozoa
to giant redwoods to humans.
• Humans are changing the other 3 spheres!
Earth System
• Closed or Open?
Select one picture describe how all four of
earth’s spheres interact.
What we know so far….
• Earth is a ________system because matter
cannot freely flow in and out yet ________
can.
• The Earth has 4 interconnected spheres:
________ __________ ______ ________
• Models are used to represent or show
processes.
Sec. 1.3 Cycles of the Earth
• A sequence of repeating events
– Duration varies
• Slow: repeat over a long period
• of time – millions of years
• Fast: repeat in a short amount of time
Types of Cycles
• Water
• Carbon
• Energy
Hydrologic Cycle
• The continuous circulation (recycling) of water
• Water in all three phases
– Solid ice, liquid water, gaseous water vapor.
Hydrologic Cycle
• Water enters the atmosphere by
– evaporation (from oceans and lakes)
– evaporation from soil, surfaces
– transpiration (from plants) also called evapo-transpiration.
• Water leaves the atmosphere as
- precipitation from clouds (rain, snow)
- infiltration (into ground)
- run-off into oceans
- condensation (dew)
Hydrologic Cycle
Carbon Cycle
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The 6th element: Carbon (C)
“building block of life”
Carbon is part of the Biogeochemical cycle
Carbon is in the earth in many forms
Carbon take various amounts of time to
cycle through
Carbon is in many forms:
SOLID
LIQUID
GAS
• Carbon goes into the atmosphere:
- burning fossil fuels
- exhaling (respiration)
- decomposing organic matter
- volcanic eruptions
• Carbon goes out of the atmosphere:
- stored in organic (living) matter
- Photosynthesis (plants take it in)
- Dissolves into oceans
Energy Cycle
(non-recyclable)
• Movement of energy
• Sources
–Sun
– Geothermal
– Tidal
The Earth’s # 1 source of energy is...
The Sun!
• Solar energy
• 99.985%
Geothermal
• Heat from
within the
Earth
• 0.013%
Geothermal
Tidal Energy
• Moon pulls on the Earth’s oceans creating
tides
• 0.002%
Human activity and the cycles
• Any human activity changes the cycles,
both positively and negatively.