Big Idea 7:

Earth Systems and PatternsDescription   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• 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.

• 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 11-7th 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.

The sun’s heat makes water evaporate into water vapor.

• The water vapor rises into the air, cools, and condenses into tiny droplets of water.

• The drops of water come together to form clouds.

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.

Precipitation

Condensation

Evaporation is when a liquid changes to a gas.

Water Cycle

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

TEMPERATURE

• Average KE of molecules– High Temperature=

increase movement of molecules= feels hot

– Low Temperature= decrease movement of molecules= feels cold

PRECIPITATION

• When a droplet reaches a certain critical mass, the force of gravity will exceed the other making precipitation fall.

• Types of precipitation: – 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

• 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 activity1. 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• 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.– Colder temperature

Elevation• 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.– 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

1. What is the difference between weather and climate? Climate is an overall figure whereas weather is what is happening immediately.

2. What are the four factors that influence weather? Temperature, pressure, moisture, wind

3. 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.

4. 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.

•

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 GeographyCopyright © 2008 John Wiley and Sons Publishers Inc.

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. – 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• 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: – Cumulonimbus – heavy

rainfall– Stratus - drizzle

SNOW• 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.

Types of Precipitate

HAIL• 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.

SLEET• 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 CHECK1. 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 CHECK1. 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• 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• 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 THE SUN• Wear sun block• Get you vehicle windows

tinted. • When exercising or

working outside, cover up• When walking outside.

use an umbrella.

FROM SEVERE WEATHER

• 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.

http://www.fema.gov/kids/

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.