THE ATMOSPHERE

The Atmosphere Air is a MIXTURE of gases. Nitrogen = 78% Oxygen = 21% Argon = < 1% CO2 = .039%

The Atmosphere Components of Air Gases Water vapor Varies 0 – 4% Depends on location and weather pattern Aerosols (solids and liquids suspended in air) Ozone 3 atoms of oxygen bonded together. O3 Ozone layer located at the top of the Stratosphere

Structure of Atmosphere Air Pressure Decreases as you rise in altitude Average = 1013.2 mb (millibars) Measured with a barometer

Structure of Atmosphere 4 layers based on temperature change. Troposphere Layer we live in Temp. decrease Stratosphere Ozone layer here Temp. increase Mesosphere Coldest Thermosphere Space shuttle Hubble telescope

Atmospheric Heating Heating of the Atmosphere from the Sun’s energy. 3 methods of heat transfer Energy Transfer Conduction by contact of molecules Convection By different densities of air (hot/cold) Radiation By electromagnetic waves Surface

GREEN HOUSE EFFECT Incoming radiation Gets absorbed by surface Mostly visible light Gets absorbed by surface Changed to Infrared (heat) Greenhouse gases: H2O CO2 Absorb Infrared heat and keep air near surface warm. Increase of Greenhouse gases Causes increase of heat trapped Called Global Warming

Ozone Layer Ozone Layer Ozone Problem O3 Absorbs UV rays from sun Changes it to heat Causes increase temperature in stratosphere Ozone Problem O3 layer is getting thinner Broken up by CFC’s (chlorofluorocarbons) Causes increase UV rays to reach surface (increase skin cancer)

Atmospheric Energy Budget What happens to the Energy of the Sun as it hits the atmosphere? Of the total energy that strikes our atmosphere: Radiation absorbed by clouds or atmosphere? Total scattered and reflected back to space? Absorbed by Earth’s surface? 100% 20% 30% 50%

Affect of Surface Material Albedo: Reflectivity of the surface High Albedo = Very reflective, poor absorber Low Albedo = Good absorber, poor reflector Color: Darker color = good absorber = Low Albedo Light color = good reflector = High Albedo

Effect of Surface Material Land Verses Water Which heats up the quickest? Which heats to a higher temperature? Which will cool down the quickest? Which will cool to a cooler temperature? How does this temperature change affect where you live?

Effect of Surface Material How does living near the ocean affect the air temperature? Winter? Summer? How does living inland affect the air temperature? Which location would have a greater change of temperature during the year?

Moisture in the Atmosphere Humidity = Amount of water vapor in the air 5g H2O/kg of air Saturated air = Holding all the water vapor it can hold. Capacity = The amount of something it can hold When something is filled to CAPACITY it is SATURATED. Water vapor Capacity or Air Direct Relationship: As air temperature INCREASES, its water vapor capacity INCREASES.

Moisture in the Atmosphere Relative Humidity = The amount of water vapor in the air compared to how much it can hold at that temperature. Given as a % of fullness. As the temperature changes throughout the day, so does the Relative Humidity.

Moisture in the Atmosphere Dew-point Temperature: The temperature the air must cool down to for the water-vapor in the air to condense as liquid onto objects. Usually occurs in the evening as the temperature decreases. Relative humidity = % Air is (holding all the water-vapor it can hold) More humid air = higher dew-point temperature What do you call it when the dew-point is below freezing?

Moisture in the Atmosphere Clouds Classified by: Height above ground Low Middle High Appearance Layered Puffy Wispy

Clouds Cloud TYPE roots: Draw here: Cirro = curly Cumulo = puffy(heaped) Strato = layered Alto = middle level Nimbo/bus = rain

Clouds Classification of clouds Examples: Description: Cirro = High and wispy Stratus = cover whole sky Cumulo = clumpy (puffy) Examples: Description: Cirrocumulus = Altocumulus = Cirrostratus = Nimbostratus = Cumulonimbus =

Name each cloud type:

Cumulonimbus cloud = Thunderstorms Heavy down pour of rain Thunder and lightning Gusty winds Hail Tornado possible Cumulus Updraft Breaks clouds builds vertical up