Download presentation
Presentation is loading. Please wait.
Published byLorin Mosley Modified over 9 years ago
1
Earth’s Atmosphere What’s Up There? Image Source: www.NASA.gov
2
The atmosphere is a layer of gasses that surrounds our planet 90% of its mass is within about 11 km (6 mi) of the surface The atmosphere is very thin compared to the size of Earth Image Source: NASA Image Source: www.NASA.gov
3
The Atmosphere is Layered Exosphere Thermosphere Mesosphere Stratosphere Troposphere Altitude Image Source: www.NASA.gov 8-14.5 Km 50 Km 85 Km 600 Km
4
Atmosphere Ionosphere (Neutral) Thermosphere Mesosphere Stratosphere Troposphere (Charged) F Layer E Layer D Layer Image Source: www.NASA.gov
5
Neutral layers commonly defined by: Changes in Temperature Image Source: www.srh.NOAA.gov
6
What’s in the Air we Breathe? 78% Nitrogen (N 2 ) 21% Oxygen (O 2 ) 1% Other Water (H 2 O) Argon (Ar) Carbon Dioxide (CO 2 ) Neon (N) Helium (He) Methane (CH 4 ) Hydrogen (H) Nitrous Oxide (N 2 O) Ozone (O 3 ) N2N2 O2O2 other
7
Troposphere (0 - 15 km) Weather happens here Thinnest at poles, thickest at equator 90% of mass found here Warmed by radiation from Earth As you go up: – Temperature drops – Pressure drops Image Source: www.Public-Domain-Photos.com
8
Stratosphere (15 – 50 km) Contains the ozone (O 3 ) layer – Absorbs harmful ultraviolet radiation (UVC and many UVB rays) As you go up: – Temperature increases (ozone layer causes this) – Pressure drops Dry
9
Mesosphere (50 – 85 km) Coldest layer (coldest place on the planet!) As you go up: – Temperature drops – Pressure drops Meteors burn up here Image Source: www.NASA.gov
10
Thermosphere (85 – 600 km) Very few molecules Incoming solar energy readily absorbed As you go up: – Temperature increases – Pressure drops Space shuttle, International Space Station and commercial satellites orbit here Same altitude as most of Ionosphere; auroras occur here Image Source: www.NASA.gov
11
Exosphere (600+ km) Atoms and molecules escape into space – 5x10 25 molecules lost every second (That’s 50,000,000,000,000,000,000,000,000!) Don’t worry: atmosphere should last several more billion years Upper limit not well defined Image Source: Hubblesite.org
12
Ionosphere Region of charged ions (positive) and electrons within Thermosphere. Ionosphere represents only about 2% of Thermosphere. Electrons are torn off atoms by sunlight of short wavelengths (called ionization) Electrons don’t recombine easily because the distance between molecules is large at high altitudes and collisions are not frequent
13
Ionosphere Discovery In 1901 Marconi received a radio signal from North America in Europe. It must have bounced off something in the atmosphere, otherwise it couldn’t have reached around the curve of the earth! Image Source: oceanservice.noaa.gov
Similar presentations
© 2024 SlidePlayer.com Inc.
All rights reserved.