Transcript Big Idea 7 :

Big Idea 7:
Earth Systems and Patterns
Description
The scientific theory of the evolution of Earth states that
changes in our planet are driven by the flow of energy and
the cycling of matter through dynamic interactions among the
atmosphere, hydrosphere, cryosphere, geosphere, and
biosphere, and the resources used to sustain human
civilization on Earth.
Benchmark Number &Descriptor
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SC.6.E.7.1
Differentiate among radiation,
conduction, and convection, the three
mechanisms by which heat is
transferred through Earth's system.
SC.6.E.7.2
Investigate and apply how the cycling
of water between the atmosphere and
hydrosphere has an effect on weather
patterns and climate.
SC.6.E.7.3
Describe how global patterns such as
the jet stream and ocean currents
influence local weather in measurable
terms such as temperature, air
pressure, wind direction and speed,
and humidity and precipitation.
SC.6.E.7.4
Differentiate and show interactions
among the geosphere, hydrosphere,
cryosphere, atmosphere, and
biosphere.
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SC.6.E.7.5
Explain how energy provided by the
sun influences global patterns of
atmospheric movement and the
temperature differences between air,
water, and land.
SC.6.E.7.6
Differentiate between weather and
climate.
SC.6.E.7.7
Investigate how natural disasters have
affected human life in Florida.
SC.6.E.7.8
Describe ways human beings protect
themselves from hazardous weather
and sun exposure.
SC.6.E.7.9
Describe how the composition and
structure of the atmosphere protects
life and insulates the planet.
EARTH’S SPHERES
ATMOSPHERE
• A gaseous sphere
surrounding the Earth
• Consists of 4 layers:
– Troposphere: layer in
which we live; weather
occurs; clouds form.
– Stratosphere: solar
radiation; temperature
increases; ozone layer
is found
– Mesosphere: coldest
layer in atmosphere
– Thermosphere:
Furthest away from
Earth; helps absorb
radiation
ATMOSPHERE
• Energy:
– Sun is the source
for 99% of heat
energy on Earth.
• 25% - reflected by
atmosphere
• 5% - reflected by
ice and snow
• 25% - absorbed by
atmosphere
• 45% - absorbed by
Earth’s surface
• Energy Transfer
– Energy is transferred
3 ways (see Big Idea 11-7
th
grade for more information)
• Conduction –
particles must touch
to transfer energy.
• Convection particles circulate to
transfer energy.
• Radiation – energy
travels in the form of
waves.
– Example:
Greenhouse Effect
“WATER, WATER,
EVERYWHERE”
HYDROSPHERE
• Includes all of the water
on Earth found in
streams, lakes, the soil,
groundwater, and the air
• 71% of the Earth is
covered by water.
– Salt water = 97% (oceans)
– Fresh water = 2.8%
(icecaps, glaciers, lakes,
streams, groundwater)
CRYOSPHERE
• Part of the Earth's
hydrosphere comprised
of frozen water
• The cyrosphere is a
sensitive element of the
climate system providing
a key indicator of climate
change.
Water regulates the temperature on
Earth.
The Water Cycle
• Water on Earth is recycled through
the Water Cycle.
• The Water Cycle consists of the
following activities:
– Evaporation
– Condensation
– Precipitation
– Percolation
– Runoff
– Transpiration
The Water Cycle
• A water cycle is the way water moves from the air to land
and back.
Condensation
• The water vapor rises into the air, cools, and
condenses into tiny droplets of water.
• The drops of water come together to form
clouds.
Water Cycle
Evaporation is when a
liquid changes to a
gas.
The sun’s heat makes
water evaporate into
water vapor.
Precipitation
The water drops
become heavy and
fall as rain, sleet,
snow, or hail.
The rain falls or snow melts
and flows to rivers, lakes, and
oceans.
WHY THE WATER CYCLE
IS IMPORTANT
LITHOSPHERE
• The Earth's solid
surface, often
called the crust of
the Earth.
• Included are:
continental and
oceanic crust as
well as the various
layers of the
Earth's interior
BIOSPHERE
• Contains all life on
Earth, including
human, and all
organisms
• The biosphere
extends to any place
that life (of any kind)
can exist on Earth.
• This layer relies on a
continuous supply of
energy from the sun.
• Contains the factors needed
for life:
– Water
– Moderate temperature
– Food source
• Energy is in constant flow
throughout the Biosphere.
– Animals/plants break
down and decompose.
– Elements such as carbon
dioxide and nitrogen are
released.
– Resources are used over
again – Carbon/Nitrogen
Cycles.
CARBON CYCLE
• Every living thing
contains carbon.
• Importance:
– Photosynthesis –
uses carbon
dioxide and gives
off oxygen
(producers).
– Respiration – uses
oxygen and gives
off carbon dioxide
(consumers).
NITROGEN CYCLE
• Nitrogen is found in
our atmosphere.
• It provides soil with
nutrients.
• Plants and animals
use nitrogen.
• When plants/animals
decompose in/on the
ground, nitrogen
seeps in creating
fertile soil.
SPHERE RECAP
– Lithosphere - All
processes associated
with the solid earth
– Hydrosphere - All
processes associated
with water
– Atmosphere - All
processes associated
with the gases that
envelope the earth
– Biosphere - All
processes that involve
living organisms
• If a change in a
sphere happens, a
chain reaction
could take place in
Earth’s Cycles
• Earth’s Cycles
include:
– Water
– Carbon
– Nitrogen
KNOWLEDGE CHECK
1. Name 4 Earth’s spheres.
2. How is energy transferred
throughout the atmosphere?
3. What two cycles occur in the
Biosphere?
KNOWLEDGE CHECK
1. Name 3 of Earth’s spheres.
Atmosphere, Hydrosphere,
Biosphere, Lithosphere
2. How is energy transferred
throughout the atmosphere?
Conduction, Convection, Radiation
3. What two cycles occur in the
Biosphere? Carbon cycle, Nitrogen
cycle
CLIMATE and
WEATHER
What Causes Climate?
• Overall/average temperature and
precipitation for an area
• Climate is determined by two basic
factors:
– temperature
– precipitation
CLIMATE FATORS
PRECIPITATION
TEMPERATURE
• Average KE of molecules
– High Temperature=
increase movement of
molecules= feels hot
– Low Temperature=
decrease movement of
molecules= feels cold
• When a droplet reaches a
certain critical mass, the
force of gravity will
exceed the other making
precipitation fall.
• Types of precipitation:
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Rain
Snow
Sleet
Hail
Climate Zones
• The Earth’s climate can be divided into 3
climate zones.
– Based on average temperatures
• 3 major climate zones on the Earth
– Polar
– Temperate
– Tropical zones.
POLAR CLIMATES
• The average yearly temperature is
below freezing.
• Even during the warmest months of
the year, the temperature does not go
over 10°C
TEMPERATE CLIMATE
• Located between the tropics and the
polar tropics
• Generally contains four seasons
• Climate can be broken down into four
categories:
– Oceanic
– Mediterranean
– Humid subtropical
– Continental
World map with temperate zones
highlighted in red.
TROPICAL CLIMATE
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Cover the largest area of Earth
Experience hot and humid weather
Much rainfall
Seasons are defined by precipitation.
CLIMATE OVER TIME
• There are three
natural factors
responsible for climate
change over time:
1. Slow drifting of
the continents
2. Changes in the
sun’s energy
output
3. Variations in the
position of the
Earth relative to
the sun
• Changes related to
human activity
1. Burning of fossil fuels
A petrochemical refinery in
Grangemouth, Scotland, UK
KNOWLEDGE CHECK
1. What determines the overall climate
of a specific area?
2. How many major climate zones are
located in the world?
3. List 3 factors that contribute to
climate change.
KNOWLEDGE CHECK
1. What determines the overall climate of a
specific area?
Temperature and precipitation
2. How many major climate zones are
located in the world?
3 major climate zones
3. List 3 factors that contribute to climate
change.
Changes in the sun’s energy. Changes in
the location relative to the sun. Burning of
fossil fuels.
WHAT IS WEATHER?
• The current state of the atmosphere
...what is happening right now.
KEY IDEAS ABOUT
WEATHER
• The sun warms the Earth’s surface and all
the air above the surface.
• Earth’s highest temperatures are at the
equator and the coldest at the poles.
• The air above land is warmed more quickly
than air above water.
• Warm air expands and rises, creating an
area of low pressure; cold air is dense and
sinks, creating an area of high pressure.
TODAY THE WEATHER
IS…
• Conditions that affect weather:
–Temperature
–Pressure
–Moisture content
–Winds
TEMPERATURE
• Three natural factors that affect the
temperature of a particular location:
– Latitude
– Elevation
– Presence of ocean and land
• Warm air is light - rises up.
• Cold air is heavy – sinks.
TEMPERATURE
Latitude
Elevation
• Latitude is the
measurement of a
specific location on Earth
relative to its equator.
• The further away from the
equator the less sunlight
that this location receives.
• Since air is "clear," sunlight
passes through it easily and
heats the ground.
• The atmosphere then gets
heated from the ground, and
the atmosphere is warmer near
the ground.
• As warm air rises from the
ground, it expands and cools.
– Colder temperature
– result = colder air at higher
altitudes than at the surface
TEMPERATURE
Land
• Organic materials such
as plants and animals
tend to absorb energy.
– Air temperature in a
forest is usually cooler
than the temperature
in a desert.
• Desert area tends to
reflect energy.
– Air temperature can be
raised by as much as
10 degrees.
Ocean
• Water absorbs vast amounts of
energy from the sun. Likewise,
bodies of water release energy
very slowly. For this reason,
areas near water are usually
more mild.
• Because of water’s ability to
absorb heat, store it, and
release it later, the Earth’s
oceans have an important role
in helping to moderate its
temperature.
KNOWLEDGE CHECK
1. What is the difference between
weather and climate?
2. What are the four factors that
influence weather?
3. How does elevation and latitude
affect temperature?
4. How does the temperature of land
differ from the oceans?
KNOWLEDGE CHECK
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4.
What is the difference between weather and climate?
Climate is an overall figure whereas weather is what is
happening immediately.
What are the four factors that influence weather?
Temperature, pressure, moisture, wind
How does elevation and latitude affect temperature?
Latitude determines how much sunlight an area receives;
elevation relates to how much the air cools before it
reaches an area.
How does the temperature of land differ from the oceans?
Land: more vegetation/obstacles the lower the temperature
(absorbs energy)
Water: absorbs a lot of energy from the sun and helps
regulate the Earth’s temperature.
UNDER
PRESSURE
AIR PRESSURE
• Caused by the weight
of all the air in the
atmosphere pressing
down on Earth
• Air pressure changes
with:
– Altitude
– Temperature of air
• Change in pressure =
change in weather
• Air Pressure is
measured in
millibars (mb) on a
barometer.
• The simplest kind
of barometer is a
mercury barometer,
and pressure is
measured in mm
in/of mercury.
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LOW PRESSURE
• Warm surface
conditions produce
low pressure near
the surface.
• Warm air is
buoyant & light,
having the
tendency to rise,
causing surface
pressure to fall
• Lows are areas of
low pressure with
the lowest pressure
at the center.
• Lows usually bring
wet, cloudy
weather.
HIGH PRESSURE
• Cold surface
conditions produce
high pressure near
the surface.
• Cold air is heavy &
dense and has a
tendency to sink,
causing surface
pressure to rise.
• Highs are areas of
high pressure with
the highest
pressure at the
center.
• Highs bring sunnier
and dry weather.
KNOWLEDGE CHECK
1. What is air pressure?
2. Describe the difference between an
area of high and low pressure.
KNOWLEDGE CHECK
1. What is air pressure?
The weight of the air pressing down on
Earth’s surface
2. Describe the difference between an area
of high and low pressure.
Low Pressure: Warm air rises leaving
causing pressure to fall; wet weather
High Pressure: Cold air sinks causing
pressure to increase; dry weather
MOISTURE in the AIR
HUMIDITY
• The amount of water vapor in the air
• The maximum quantity of moisture
that can be held in the air depends on
air temperature.
Relative humidity changes
when:
1. Atmosphere gains or loses water vapor.
• Evaporation
2. Temperature changes.
• Lower temperature relative humidity
rises
• Raise temperature relative humidity
decreases
Visualizing Physical Geography
Copyright © 2008 John Wiley and Sons
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Humidity and Humans
• The higher the
humidity rate, the
more
uncomfortable we
feel.
– The air is
saturated, and
therefore sweat will
not evaporate off
your body.
PRECIPITATION
• Precipitation is the
release of water
from the
atmosphere to the
Earth’s surface as
a solid or liquid.
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Rain
Snow
Hail
Seet
• In order for
precipitation to be
created, air must
move upward and
become colder.
• The type of
precipitate which
hits the ground
depends on the
temperature in the
lower part of the
atmosphere.
Precipitation in the
United States
Types of Precipitate
RAIN
SNOW
• Rain starts when small
droplets of water in the
clouds join together until
they get too big and
heavy.
• Eventually, these droplets
fall from the clouds and
hit Earth’s surface.
• Clouds involved:
• Snow starts the same
way as rain with tiny
droplets of water joining
together in clouds until
they are too heavy.
• When the droplets fall, it
is important that the air is
at a freezing temperature
for snow to form.
– Cumulonimbus – heavy
rainfall
– Stratus - drizzle
Types of Precipitate
HAIL
SLEET
• Hail begins as tiny ice
pellets that collide with
water droplets.
• Formed in cumulonimbus
clouds
• Both gravity and
downdraft thunderstorm
winds pull the pellets to
Earth’s surface.
• Ice pellets are similar to
hail but smaller and more
likely to occur in winter
• In winter states, people
refer to sleet as rain
mixed with snow that
melts as it falls.
• Rain passes through a
layer of clouds with
freezing temperatures.
KNOWLEDGE CHECK
1. What is humidity, and what factor
affects it?
2. How does humidity affect humans?
3. List 4 types of precipitation.
4. List 2 factors that are needed in
order for precipitation to occur.
KNOWLEDGE CHECK
1. What is humidity, and what factor affects it?
Amount of water vapor in the air, depends on
temperature.
2. How does humidity affect humans?
The more humid it is, the less sweat does not
evaporate from the body leaving a person hot
and very sweaty.
3. List 4 types of precipitation.
Rain, Snow, Sleet, Hail
4. List 2 factors that are needed in order for
precipitation to occur. Air must move upward
and become cooled, the temperature of the air
close to the ground will determine what type of
precipitation will occur.
WINDS
WHAT IS WIND?
• When there is a difference in air
pressure in the atmosphere, wind is
created.
– Unequal heating causes changes in air
pressure.
• Wind always moves from areas of
high pressure to areas of low
pressure.
THE JET STREAM
• Fast flowing, narrow
air currents found in
the atmospheres
between the
troposphere and the
stratosphere
• Caused by heating of
the Earth and its
rotation
• These winds flow from
west to east around
the world.
Jet streams flow from west
to east in the upper portion
of the troposphere.
GLOBAL WIND
DIRECTION
• Coriolis Effect –
Rotation of the Earth
causes moving air and
water to change
directions.
• Northern Hemisphere
winds curve to the
right.
• Southern Hemisphere
winds curve to the left.
WIND SPEED
• Result in a large pressure
difference
• Strong winds also occur in low
latitudes due to stronger heating
and greater pressure differences.
– Hurricanes and tornadoes are
examples.
KNOWLEDGE CHECK
1. What must be different for wind to
occur?
2. What is the Jet Stream?
3. What helps move winds around the
globe?
4. What factor determines wind speed?
KNOWLEDGE CHECK
1. What must be different for wind to
occur?
Air pressure
2. What is the Jet Stream?
Fast flowing, narrow air currents
found in the atmospheres
3. What helps move winds around the
globe?
Coriolis Effect
4. What factor determines wind speed?
large pressure difference
HOW DO WE PROTECT
OURSELVES?
HAZARDOUS WEATHER of
FLORIDA
LIGHTNING
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Lightning is an electric current.
Cloud fills with electrical charges
– Positive charges on top of cloud
– Negative charges on the bottom
of cloud
Ground on the Earth contains
electrical charge. Tall objects help
carry these charges towards the air.
Eventually the charges from the
ground connect with a charge
reaching down from the clouds and
- zap - lightning strikes!
• ** Tampa is considered the
Lightning Capital of North
America
THUNDERSTORMS
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Generates lightning and thunder
Storms form when warm humid air
rises in an unstable area.
Severe thunderstorm can have
winds traveling at 80 kilometers
per hour and hail more than 2
centimeters in diameter.
Thunderstorms can also cause:
– Flash flooding
– Strong winds
– Hail
– Tornadoes
HAZARDOUS WEATHER of
FLORIDA
TORNADO
• Develop from severe
thunderstorms
• Characterized by a funnel
cloud moving over land
– Known as water spouts when
moving over water
• 200 m in diameter (20
classrooms long)
• Generally lasts less than 10
minutes
HURRICANES
• Largest storm that occurs on
Earth
• Classified as a low pressure
system that forms over tropical
oceans
• May go on for days
• Weakens when hits cool water
or strikes land
• Florida has had over
488 tropical storms/hurricanes.
PROTECT YOURSELF
FROM SEVERE
WEATHER
FROM THE SUN
• Wear sun block
• Get you vehicle windows
tinted.
• When exercising or
working outside, cover up
• When walking outside.
use an umbrella.
http://www.fema.gov/kids/
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THUNDERSTORM: When a storm is
coming, look for darkening skies, flashes of
light ,or increasing wind. Listen for the sound
of thunder. If you can hear thunder, you are
close enough to the storm to be struck by
lightning. Go to safe shelter immediately.
HURRICANE: Listen to a radio or television
for weather updates, and stay in touch with
your neighbors about evacuation orders.
Assemble your disaster supplies kit. Store
extra water now! Check to make sure you
have enough food.
TORNADO: Listen to a radio. or watch
television for weather updates. If a tornado
is coming, you MUST seek shelter. An
underground shelter is best, such as a
basement or storm shelter. If you don’t have
a basement, find an inside room or hallway
or closet on the first floor AWAY FROM
WINDOWS.
KNOWLEDGE CHECK
1. What are four common hazardous
weather conditions common in
Florida?
2. Since the sun’s rays are strong in the
state of Florida, list two ways to help
protect yourself.
3. What is one common safety
measure to take amongst any severe
weather threats?
KNOWLEDGE CHECK
1. What are four common hazardous weather
conditions common in Florida?
Lightning, thunderstorms, tornados, hurricanes
2. Since the suns rays are strong in the state of
Florida, list two ways to help protect yourself.
Wear sunscreen; stay covered up.
3. What is one common safety measure to take
amongst any severe weather threats?
Listen to a radio, or watch television for weather
updates; have a plan.