The Dynamic Earth

BELLWORK 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 Atmosphere A mixture of gases that surround Earth Made up of 4 layers: Troposphere Stratosphere Mesosphere Thermosphere

Troposphere 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

Stratosphere 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)

Mesosphere Temperature starts to decrease again as you increase in altitude coldest layer temperatures less than -100 F

Thermosphere Very few molecules Can cause Northern Lights by radiating energy

The 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 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 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 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 Effect Greenhouse effect … Greenhouse gases (Water vapor, CO², Methane, NO², SO²)

QUIZ 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 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.