The Dynamic EarthThe Dynamic Earth

BELLWORKBELLWORK

Denver is known as the Mile-High City because its altitude is exactly one mile above sea level.

Based on this information, why do you think it is a little harder to breathe in Denver?

The AtmosphereThe AtmosphereA mixture of gases that surround Earth

Made up of 4 layers:TroposphereStratosphereMesosphereThermosphere

TroposphereTroposphere

• 75% of the mass of the earth’s air found here

• What gases make up Earth’s atmosphere?-78% N, 21% O

• Where weather occurs

• Where we live

StratosphereStratosphere

Similar in composition to troposphere except:

• 1,000 times less water vapor,

• Ozone 1,000 times greater,

• Keeps out 99% of sun’s harmful radiation (natural sunscreen)

MesosphereMesosphere

Temperature starts to decrease again as you increase in altitude

coldest layer

temperatures less than -100 F

ThermosphereThermosphere

Very few molecules

Can cause Northern Lights by radiating energy

http://goo.gl/gwV5ES

The SunThe Sun

Provides energy in the form of sunlight- 34% reflected back into space- Most rest of 66% converted to heat

Supplies energy for photosynthesis

The SunThe Sun• Heat energy can travel through 3 different methods:

1) Conduction: One object transfers heat though direct contact with another object.

Example: Touching a hot stove will burn you.

2) Convection: Heat is transferred through air currents.Example: Hot air rises, cold air sinks.

3) Radiation: Heat is transferred from one object to another through the air.

Example: Feeling the heat of a fire without touching it.

The SunThe Sun

QUESTION:

The sun is responsible for most of the weather that we see on Earth.

Which of the 3 methods of heat transfer causes this?

Greenhouse EffectGreenhouse Effect

Certain gases in Earth’s atmosphere trap sunlight and radiate heat back toward Earth.

carbon dioxide, water vapor, methane, etc.

This causes Earth’s temperature to rise

Without the greenhouse effect, the Earth would be too cold to live on!

The Natural Greenhouse EffectThe Natural Greenhouse Effect• Greenhouse effect … Greenhouse gases

(Water vapor, CO², Methane, NO², SO²)

QUIZQUIZ

Assignment:

Create a five question quiz about everything we have learned so far (geosphere and atmosphere).

You will be graded based on the quiz you create.

QUIZ RULESQUIZ RULES

Must include:•At least 2 multiple choice•At least 1 discussion (must explain “why”)•At least 1 definition•The other is your choice.

At least 2 questions must be about geosphere and at least 2 must be about atmosphere. The other is your choice.