Do Now 5 Minutes Topic The Atmosphere - Layers You will all be following along with today s notes with fill-in notes. After notes, you ll have time to finish your poster projects. At the top of your notes, I would like you to recall and list the layers of the atmosphere.
Homework Complete the Carbon Cycle worksheet (Two Days Late).
Upcoming Quiz On Wednesday, we will have a short quiz. Quiz is on the Hydrosphere, Biosphere, and small amount of Atmosphere. We will review in class on Tuesday, 11/25.
Atmosphere The last, and outermost portion of Earth s spheres is the atmosphere.
Atmosphere Earth s atmosphere serves as a protective boundary for all life forms on the planet. Not all planets have suitable atmospheres for organisms. What s wrong with the atmosphere on Venus? What s wrong with the atmosphere on Mars?
Atmosphere of Venus Venus s atmosphere is WAY too thick and traps in heat.
Atmosphere of Mars Mars s atmosphere is too thin to keep the planet a regular temperature and protect it from space junk.
Creation of our Atmosphere How did our atmosphere form? Earth s first atmosphere was made of helium and hydrogen. This helium and hydrogen escaped though, since they re so light.
Creation of our Atmosphere Earth s second atmosphere was formed through volcanic eruptions. Volcanos released H 2 O, CO 2, and ammonia (NH 3 ).
Creation of our Atmosphere Earth s third and current atmosphere was a result of plants and animals. Most CO 2 dissolved into the ocean. Bacteria converted sunlight + CO 2 into O 2 Sunlight broke apart NH 3, leaving H to escape.
Atmosphere of Earth There are five layers of Earth s atmosphere:
Atmosphere of Earth Use a pneumonic to help yourself remember the order of the layers: Exosphere tra Thermosphere ermals Mesosphere an Stratosphere inky Troposphere iceps
Troposphere Contains 3/4 of the atmosphere s mass, but it is very thin! Goes from the surface of the Earth, to 7 miles up (11 km). Almost all of the clouds we see are in the troposphere. The movement of the troposphere is responsible for weather!
Troposphere The higher up you go in the troposphere, the colder it is (Temp at top: -70.6 ºF) At the top, it stops getting colder.
Stratosphere Extends from 7 31 miles (11 50 km) up from the surface. The gases in the stratosphere do not mix very well meaning if pollution reaches the stratosphere, it stays there. As you ascend the stratosphere, it gets warmer. (Temp at top: 26.6 ºF) Warmest temperatures are at the top of the stratosphere.
Stratosphere Planes fly in the stratosphere
Stratosphere The Ozone layer (O 3 ) is in the stratosphere as well. The upper layer of the stratosphere is the warmest due to UV rays from the sun absorbing and scattering at the top. The deeper you go down, the UV rays do not penetrate as deep.
Stratosphere If we did not have the ozone layer, there would not be life on Earth.
Mesosphere Extends 31 50 miles (50 80 km) above the surface of the earth. As you ascend in the Mesosphere, temperature decreases. Temperatures reach as low as -226ºF Cold temperatures are due to seasonal changes, less solar heating, and CO 2 cooling.
Mesosphere Meteors burn up meteors when they approach Earth. This is why Earth is not covered in craters like other planets.
Mesosphere Here s a video of the Mesosphere in action. Link This is the least-researched layer of the atmosphere. It s too high for planes to reach, but too low for orbital spacecraft to navigate.
Thermosphere Last official layer of the atmosphere. The air is INCREDIBLY thin here. Thermosphere extends 50 miles above the surface of the Earth and beyond. The temperature here is very high (3,630 ºF) due to solar activity.
Thermosphere Since the air is so thin, and there are so few gas molecules, you would actually not feel that heat. Molecules of air are so far away from each other, sound does not transmit either.
Thermosphere The International Space Station maintains its orbit in the thermosphere
Thermosphere Aurorae borealis occur in the thermosphere as well
The last layer. Exosphere This is where the atmosphere ends and merges with space. Sometimes it is just considered part of outer space. It is mostly made up of hydrogen, helium, CO 2, and atomic oxygen.