Download Earth as a System Power point File

Earth’s Systems
and Cycles
Essential questions
 Describe the type of system Earth is and give your
reasoning.
 Describe what happens within a positive loop and give
an example.
 Give an example of Earth’s spheres interacting in your
backyard. (state object, sphere it is in and how they
interact)
Warm up
 What do you think of when you hear the word
system?
 Brainstorm a list of systems with the person next to
you
Earth as a System
 A system is a part of the universe that can be
studied separately.
 Scientists sometimes study individual parts of the
Earth such as:
 How mountains form
 Classification of life forms
 How tornadoes form
Today we understand that the all parts of the Earth
are connected and interacting
The best way to understand the Earth is not to study
the parts in isolation but as one system
Systems have
Inputs and Outputs
 SKETCH ON THE SIDE
http://www.schuelers.com/ChaosPsyche/pa
rt_1_10.htm
Closed vs. Open Systems
Closed Systems
Open Systems
Matter does not enter or
leave
Matter enters and leaves
Energy enters and leaves
Energy enters and leaves
Earth is a Closed System
Energy from the sun is
absorbed by the Earth’s
atmosphere and surface
during the day
Energy is lost back into space
at night as heat.
The matter on Earth is the same
matter that was here when
Earth formed.
Matter changes form but the
TOTAL amount of matter
remains the same
.
Mt Etna lava picture source:
:http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17479
How is a jar of sun tea
like the Earth?
 Sun tea is made
with tea bags and
water in a closed jar
that is left out in the
sun.
 How is this similar to
Earth as a closed
system?
Except….
What happens when a meteorite hits Earth?
OR when NASA send up space ships or
satellites?
A tiny amount of Hydrogen atoms are lost to space.
Overall, Earth is still considered a closed system.
This means our resources must be conserved
and protected.
Feedback Loops
 Within a system feedback loops are often
identified to help define how the system works.
 Feedback loops can either be positive or
negative
 Positive Feedback Loops: chain reactions
that moves part of the system towards
extremes (hi/lo)
 Negative Feedback Loops: chain reactions
that moves part of the system towards being
stable
Bank Account
Body Temperature
Systems have feedback loops
 Negative feedback – most common
 Think of a thermostat
 You set your thermostat for 70 degrees
 It senses the air temperature is below 70 so it signals the
heater to turn on
 The heater warms the air in the room
 The thermostat senses the temperature is at 70 so it
signals the heater to turn off
 This type of feedback helps to maintain equilibrium in a
system
Positive Feedback loop from
NASA
Positive Feedback
 In a positive feedback loop,
it’s like your foot is stuck on
the accelerator and you keep
going faster!
 For more on systems and
modeling, see
 Systems Theory and
Modelinghttp://science.csumb.
edu/esse21/index.php
 Image courtesy of Hugo
Ahlenius, UNEP/GRID-Arendal
Maps and Graphics Library.
Earth’s system includes 4
spheres that interact
 The Atmosphere consists of the gases that surround the Earth = AIR
 The Geosphere (also called lithosphere) consist of the rocks,
minerals, soils, ocean basins and Earth’s interior = ROCK
 The Hydrosphere includes the water in oceans, rivers, groundwater,
clouds, lakes, ice caps and glaciers = WATER
 The Cryosphere is sometimes used to describe frozen water in ice cap
and glaciers
 The Biosphere includes all things living or coming from living
things. = LIFE
 Visualize Earth’s spheres:
http://www.classzone.com/books/earth_science/terc/content/visualizat
ions/es0102/es0102page01.cfm?chapter_no=visualization
Earth’s Sphere’s Interact
 An erupting volcano
releases lava, volcanic
bombs (geosphere) and
gases and ash into the
air (atmosphere), the
animals are suffocated
(biosphere), plants burn
up (biosphere), ash
flows fill rivers
(hydrosphere).
http://volcano.und.edu/vwintl/vwintl.html
More interaction examples
Plants and animals ( biosphere) breathe,
taking in oxygen ( atmosphere) and
releasing CO2.
More interaction examples
Fill in the sphere names
People (
) drill wells into the Earth’s crust
( ) drawing out groundwater (
) used for
drinking and irrigation.
Hurricanes form over the ocean (
),
sweep onto the shore (
) and can
damage homes and habitats (
) on land.
Interacting Practice: What is
interacting?
 LIST the items
along with what
sphere they belong
 LIST how the items
are interacting with
one another
Summary
Describe the type of system Earth is and
give your reasoning.
Describe what happens within a positive
loop and give an example.
Give an example of Earth’s spheres
interacting in your backyard. (state object,
sphere it is in and how they interact)
Cycles involve interactions
between the spheres
A cycle is a event or
process that repeats
over and over again.
Examples:
The water cycle
The carbon cycle
The nitrogen cycle
A biogeochemical cycle
moves nutrients
between living and
nonliving portions of the
Earth
http://www.windows.ucar.edu/tour/link=/earth/Water/co2_cycle.html&edu=mid
The Water Cycle
 Water leaves the oceans
and other bodies of water
through evaporation and
the leaves of plants through
transpiration.
 Solar energy powers this
part of the water cycle.
 Water vapor cools and
condenses to make cloud
droplets or ice crystals that
merge to form rain and other
forms of precipitation.
 Gravity pulls the
precipitation back down to
the surface.
See U.S.G.S for a quick summary:
http://ga.water.usgs.gov/edu/watercyclesumma
ry.html
Precipitation can be rain, snow,
sleet or hail
 Precipitation falls to
the Earth
 and either infiltrates into
the ground,
 becomes runoff that
moves across the
surface,
 lands in a body of water
 or is evaporated back up
into the sky
 Can you label A - G?
Rita Haberlin’s Lecture notes:
http://members.aol.com/rhaberlin/hcpptnts.htm
We Impact
the Water Cycle
Developing land reduces the
amount of water that can sink
into the ground, infiltration and
increases the amount of runoff
that occurs.
This causes other problems such
as:
Soil erosion
Loss of ground water recharge
Flooding
Pollution of lakes and streams
Judith Earl slideshow:
http://managingwholes.com/photos/erosion/pictures/slide17.html