1. How many inches of rain does Manitou Springs receive in May?

2. What is the highest average temperature?3. Is there more precipitation in the winter or summer months?

Weather and Climate

The AtmosphereThe Atmosphere

• Review:– Earth’s atmosphere is the envelope of gases

that surround the Earth.

Weather and ClimateWeather and Climate

• Weather – condition of the atmosphere at a given time and place

• Climate – weather conditions in a geographic region over a long period of time

Weather and ClimateWeather and Climate

• What is San Antonio’s weather like today?

• What is the climate of San Antonio?

Solar Energy

Factors that affect climate: The Sun

Factors that affect climate: The Sun

– The sun’s energy reaches earth– Half of the energy is reflected back into space

or absorbed by the atmosphere– The other half is absorbed by the Earth’s

surface and converted into heat energy– The atmosphere traps this heat in a process

called the greenhouse effect– The greenhouse effect helps keep the planet

warm

The Greenhouse Effect

Global WarmingGlobal Warming

• Global warming – process by which the Earth grows warmer over a period of time

• Human caused or natural cycle of the Earth?

Global Warming

• Carbon dioxide is a greenhouse gas…

• Because it absorbs heat, more carbon dioxide could enhance the greenhouse effect

Global Warming• Human activities such

as burning coal, natural gas, and oil put more carbon dioxide into the atmosphere

Global WarmingGlobal Warming

• What are some things that people are doing to help stop global warming?

Weather and Climate

• We have seen that the sun affects weather and climate.

• The air around you also affects what the weather and climate will be like…

Factors that affect climate: Atmospheric Pressure

Factors that affect climate: Atmospheric Pressure

• the air in our atmosphere has weight

• air around you is pushing on you

Atmospheric Pressure

• High Pressure– Cold air; dense, therefore it sinks– As it sinks, the air heats and dries– Usually brings stable, clear and dry weather– can equal extreme heat and bitter cold

(Think about a hot summer day here in San Antonio)

H

Clear Day

Atmospheric Pressure

• Low Pressure

• when air is heated, it expands, becomes less dense, and rises

• The water vapor the air carries may become clouds

• Brings unstable weather

• Effects on weather can vary in intensity: slight breezes and cloud cover to powerful storms w/ heavy rain and high winds

L

Atmospheric PressureAtmospheric Pressure

Factors that affect climate: Global Wind Belts

• Air pressure affects global wind patterns

• wind always flows from high to low pressure

Winds

• prevailing winds – winds that blow from the same direction most of the time

• doldrums – areas with no prevailing winds (area has little wind = problems for sailing ships)

Winds

• In the middle latitudes, the prevailing winds are called westerlies (flow from west to east)

• In the contiguous U.S. , these winds carry most weather patterns and storms from the west to the east

• Contiguous – connecting or bordering

• “You have won a trip to anywhere in the contiguous United States!”

• What places are excluded from this prize?

Pressure and Wind Systems

Earth’s Energy Balance: Winds

Think of Earth as a living organism, always trying to reach a balance

*winds move heat and cold across the earth’s surface

Factors that Affect Climate:Oceans

Ocean InfluenceOcean Influence

Water heats and cools more slowly than land, making

coastal areas milder than inland areas

Kansas City has much colder winters and much warmer summers than San Francisco.

Factors that affect climate:Ocean Currents

Factors that affect climate:Ocean Currents

• Ocean Currents – rivers of seawater that flow in a circular path

–Created by Earth’s winds, rotation, and the temperatures of the water

Ocean Currents

Help maintain Earth’s energy balanceHow?

• Moves heat back and forth between the tropics and the polar regions

• Warm currents carry heated water from the tropics toward the cooler middle latitudes

Gulf StreamGulf Stream

Warm current off the coast of Florida flowing north to Europe

Gulf StreamGulf Stream

• What North American country is along the same latitudes as Western Europe?

• Without the Gulf Stream, temperatures in Western Europe would be lower

Gulf StreamGulf Stream

• Some scientists fear that Global Warming could ultimately lead to the shutdown of the Gulf Stream

• Melting ice may stop the circular flow of the water

= Europe will be in a mini ice-age

California CurrentCalifornia Current

• Cool current

• Southward flowing off the west coast of the U.S. that cools the land nearby

California CurrentCalifornia Current

Factors that affect climate:

Mountains

Elevation

• Elevation – height on Earth’s surface above sea level

• An increase in elevation causes a drop in temperature

–Drops 3.5 degrees F per 1,000 ft

• Can there be snow in places that are on the equator?

Snow on the Equator

Snow near the equator

Mountains influence climates by…

• Orographic effect

–Moist air pushes against a mountain

–The air is forced to rise

–This creates clouds and causes precipitation

Orographic Effect

Orographic Effect

Windward side: side of mountain facing the wind

Orographic Effect

• Leeward side: side of mountain facing away from the wind

• Leeward side is called a rain shadow.

Let’s review

• Factors that affect climate:– Sun and latitude– Atmospheric Pressure– Global Wind Belts– Ocean (closeness to water and ocean

currents)– Mountains

Warm-up:1. What is the name of the prevailing winds in the mid-

latitudes?

2. Why do coastal areas have a milder climate than inland areas?

 

3. What keeps Europe from being much colder than it is?

• 1. What is the name of the prevailing winds in the mid-latitudes?

• 2. How does the wind affect the Earth’s energy balance?

• 3. Why do coastal areas have a milder climate than inland areas?

 

• 4. What keeps Europe from being much colder than it is?

• 5. Which side of a mountain is the dry or desert side?

The Greenhouse EffectThe Greenhouse Effect

• The Greenhouse Effect is needed = keeps the Earth warm

* Greenhouse gases = carbon dioxide, methane, water vapor, and nitrous oxide

1. What is the temperature in Nome, Alaska compared to San Antonio, Texas?2. What factor is causing this difference?3. What part of the country is currently experiencing the greatest amount of

heat?4. What type of front extends across Florida?

• Read the article: “Shading the Earth”

• Write a paragraph (7-10 sentences) about the following statement: What could be potential problems of creating a "sun shield"?

• Ideas to get you started may include cost and who pays for it....

Assignment

• El Niño—Ocean and weather pattern in which the southeastern Pacific Ocean is warmer than usual, affecting regional climates

• La Niña—An ocean and weather pattern that causes the eastern Pacific Ocean to be colder than normal

El Niño and La NiñaEl Niño and La Niña

Normal

El Niño

El Niño: Cause and Effect

• Cause:– Change in the ocean’s surface temperature

• Effect:– Changes in weather patterns around the

world

Cause and Effect

• Cause: – Atmospheric pressure north of Australia rises

• Effect: – Trade winds weaken

Cause and Effect

• Cause: – Trade winds weaken

• Effect:– Warm water flows eastward

Cause and Effect

• Cause:– Warm water flows eastward, over the cooler,

nutrient-rich waters off the Peruvian coast.

• Effect:– Sea life suffers from lack of nutrients,

fishermen cannot catch any fish.

1. How many inches of rain does Manitou Springs receive in May?

2. What is the highest average temperature?3. Is there more precipitation in the winter or summer months?

Happy Constitution

Day!

Write the Preamble to the Constitution on your warm-up sheet

“We the people..”

Preamble to the Constitution:

“We the People of the United States, in Order to

form a more perfect Union, establish Justice,

insure domestic Tranquility, provide for the

common defense, promote the general Welfare,

and secure the Blessings of Liberty to ourselves

and our Posterity, do ordain and establish this

Constitution for the United States of America.”

Declaration of Independence

"We hold these Truths to be self-evident, that all Men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the Pursuit of Happiness--That to secure these Rights, Governments are instituted among Men, deriving their just Powers from the Consent of the Governed."

Too Late to Apologize