Do Now: Work on Regents Questions (5 min) L.O: SWBAT DESCRIBE THE PROPERTIES OF THE ATMOSPHERE. (S4a,S6d S7d,S7e,) Do Now: Work on Regents Questions (5 min)

What is the Atmosphere? Atmosphere: An envelope of gases that surround a planet What prevents these gases from escaping? Answer: Gravity

L.O. SWBAT explain properties of the atmosphere Turn and talk (30 seconds) How do you think the Earth may have gotten its Atmosphere? Earth’s early atmosphere formed from“Outgassing” (releasing gas) from volcanic eruptions. L.O. SWBAT explain properties of the atmosphere

L.O. SWBAT explain properties of the atmosphere CO2, Nitrogen & other gases leaked out of early Earth’s interior through volcanoes. L.O. SWBAT explain properties of the atmosphere

L.O. SWBAT explain properties of the atmosphere ~ 1.5-2.0 billion years AFTER Earth formed, the first photosynthetic single-celled plants (Cyanobacteria/blue-green algae) added oxygen into Earth’s atmosphere. L.O. SWBAT explain properties of the atmosphere

How thin is the Atmosphere? -The Earth is 12,740 km in diameter. -The Atmosphere is only 500 km thick. -Weather as we know it occurs in the bottom 10 km of the atmosphere.

Atmospheric Composition Primary Gases: Nitrogen 78% Oxygen 21% Argon 0.9% Others 0.1% N. Donohue Jones Beach, NY January 6, 2007

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open to top of page 14. Selected properties of Earth’s atmosphere: L.O. SWBAT explain properties of the atmosphere

Atmospheric Structure Atmosphere divided into four main layers: Troposphere Stratosphere Mesosphere Thermosphere

Important Notes Troposphere: Stratosphere: The troposphere is the lowest layer (0 km to 12km above sea level.) where most of our weather occurs. Most of the atmosphere’s water vapor & the clouds are in the troposphere Troposphere is the layer of the atmosphere that surrounds us. Ends at the tropopause Stratosphere: The stratosphere contains ozone (O3) which protects us from harmful ultraviolet radiation. THE STRATOSPHERE HAS NO WEATHER!

Interesting, But Less Important Notes Mesosphere: Air is extremely thin; 99.9 % of the atmosphere’s mass is below this layer Thermosphere: At the top of the thermosphere, single molecules can move distances of 10 km before they collide with other molecules

How do you think the thermosphere got its name? * the thermosphere is very hot How do you think the thermosphere got its name?

How to read the selected properties of Earth’s Atmosphere chart: The altitudes of atmospheres layers above sea level in Kilometers & miles L.O. SWBAT explain properties of the atmosphere

Q: what is the altitude (in Km) of the troposphere? ~ 12 km above sea level L.O. SWBAT explain properties of the atmosphere

Q: what is the altitude (in Km) of the stratosphere? L.O. SWBAT explain properties of the atmosphere

The temperature Zones of each layer thermosphere: as altitude increases temperature increases mesosphere: as altitude increases temperature decreases stratosphere: altitude increases, temp increases troposphere: as altitude increases temperature decreases L.O. SWBAT explain properties of the atmosphere

As altitude increases, atmospheric pressure decreases L.O. SWBAT explain properties of the atmosphere

*nearly all the water vapor is in the troposphere. L.O. SWBAT explain properties of the atmosphere