looking at the earth’s atmosphere earth’s protective bubble nasa accessed via wikipedia

LOOKING AT THE EARTH’S ATMOSPHERE

EARTH’S PROTECTIVE

BUBBLE

NASA accessed via Wikipedia

Earth is surrounded by a blanket of air called the atmosphere

Extends near or over 600 kilometers from Earth’s surface

Held by Earth’s gravitational pull

Composed of many diff erent gases

Separated into several diff erent layers

Protects us from outer space

Blocks out dangerous rays (UV) from the sun

Quite transparent to visible light

WHAT’S SO SPECIAL?

A PROFILE OF THE ATMOSPHERE REVEALS IT CAN BE DIVIDED INTO DISTINCT LAYERS

EACH LAYER CAN BE DEFINED BY THE GASES THAT COMPRISES IT ORTEMPERATURE VARIATION OR ELECTRICAL PROPERTIES

SEPARATING THE LAYERS IS A BOUNDARY OR “PAUSE” WHERE THE GREATEST CHANGES PROPERTIES OCCUR

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Heterosphere

Homosphere

Ionosphere

The source of this material is Windows to the Universe, at http://www.windows2universe.org http://www.windows.ucar.edu/ at the National Earth Science Teachers Association (NESTA) <http://www.ucar.edu>. Windows to the Universe® is a registered trademark. All Rights Reserved

H o m o s p h er el o w e r a t m o s p h e r e

The air we breathe is very well mixed The air is comprised of

78%: Nitrogen (N2)

21%: Oxygen (O2) other 1%: “trace” gases

Argon (Ar) Carbon Dioxide (CO2)

Ozone (O3)

Water (H2O) … and more

Heterosphereupper atmosphere

The air in the upper atmosphere is very diff erent from the air we breathe

The air is not well mixed

Atoms get sorted by atomic weight

Hydrogen and Helium can sometimes escape gravity

MIXING IT UP

Wikipedia | Public Domain

Troposphere Surface ~ 15km

THE LOWER ATMOSPHERE

THE WEATHER ZONEALMOST ALL WEATHER OCCURS IN THIS LAYER

HEIGHT OF THE TROPOSPHERE VARIES FROM THE EQUATOR (15KM) TO THE POLES (9KM)

TRANSPORT OF ENERGY HEATS THIS LAYER

AS YOU GO UP … (INCREASE IN ALTITUDE)

PRESSURE DECREASESDENSITY OF GASES DECREASESTEMPERATURE DECREASES

UNIFORMLY

A TRANSITION ZONE KNOWN AS THE TROPOPAUSE IS THE BOUNDARY BETWEEN THE TROPOSPHERE AND STRATOSPHERE … ALL DRY (ALMOST)!

Kathryn Haughn


Stratosphere 15km ~ 50km

STABLE LAYER (IDEAL FOR JET PLANES

OZONE LAYER IS IN THIS LAYER

LET IT LINGER (CFC’S, VOLCANIC ASH, AEROSOLS)

WEATHER BALLOONS

AS YOU GO UP … PRESSURE DECREASESAIR IS DRY AND LESS DENSETEMPERATURE INCREASES (-52°C

~ -3°C)

99% OF THE ATMOSPHERE IS LOCATED IN THE TROPOSPHERE AND STRATOSPHERE!

A TRANSITION ZONE KNOWN AS THE STRATOPAUSE IS THE BOUNDARY BETWEEN THE STRATOSPHERE AND MESOSPHERE … WHAT PRESSURE?

NASA


THE COLD LAYER

NOCTILUCENT CLOUDS

METEORS BURN UP IN THIS LAYER

NOT EASY TO STUDY

AS YOU GO UP …PRESSURE DECREASESDENSITY OF GASES CONTINUES TO

DECREASE TEMPERATURE DECREASES (-3°C ~ -90°C)

A TRANSITION ZONE KNOWN AS THE MESOPAUSE IS THE BOUNDARY BETWEEN THE MESOSPHERE AND THERMOSPHERE … COLDEST PLACE ON EARTH!

Mesosphere

50KM ~ 85 KM

NASA


Thermosphere

85km ~ 600km

THE UPPER ATMOSPHERE

HOT! HOT! HOT!

NOT MUCH AROUND (MOLECULES THAT IS)

X-RAY AND UV RADIATION ABSORBED

SPACE SHUTTLES AND INTERNATIONAL SPACE STATION ORBIT IN THIS LAYER

SENSITIVE TO SOLAR ACTIVITY

AURORA

OVERLAPS AND SHARES SPACE WITH IONOSPHERE

AS YOU GO UP …PRESSURE DECREASESDENSITY OF MOLECULES IS EXTREMELY LOWTEMPERATURE INCREASES (-90°C ~ 2000°C)

NASA


Exosphere

600+ kmTHE ESCAPE ZONE

EXTENDS UNTIL IT MERGES WITH SPACE

UPPER LIMIT OF OUR ATMOSPHERE

COMPRISED OF MAINLY HYDROGEN AND HELIUM

SATELLITES ORBIT EARTH IN THIS LAYER

NASA


THE ELECTRIFIED REGION SHOWS YET ANOTHER WAY LAYERS OF THE ATMOSPHERE CAN BE DEFINED

Windows to the Universe® (http://windows2universe.org) © 2010, National Earth Science Teachers Association.

IONOSPHERE (60KM – TOP OF ATMOSPHERE)

AN ELECTRIFIED REGION (NOT REALLY A LAYER ITSELF) WITHIN THE UPPER ATMOSPHERE

EXISTENCE IS DUE TO THE SUN’S RADITATION THE DENSITY CHANGES FROM DAYTIME TO NIGHTTIME

AM RADIO COMMUNICATION RELIES ON THE IONOSPHERE

CONSISTS OF IONS AND FREE ELECTRONS

IONS ARE ATOMS AND MOLECULES THAT HAVE LOST OR GA INED ELECTRON(S)

STARTS AT ABOUT 60KM AND EXTENDS TO THE TOP OF THE ATMOSPHERE

DIVIDED INTO 3 LAYERS; THE D, E, AND F LAYERS

MIT Haystack

NOAA

LOWEST LAYERABSORBS GAMMA AND X-RAYSREFLECTS AM RADIO

WAVES BACK TO EARTHAT NIGHT THE LAYER

DISAPPEARS (GRADUALLY) AT NIGHT

WHAT HAPPENS TO THE AM RADIO WAVES THEN?

THE D LAYER

NOAA

THE E LAYER

PEAKS AT 105KMABSORBS X-RAYS

THE F LAYER

HIGHEST LAYERUP TO 600KM or

MOREABSORBS EXTREME

UV

MORE ON THE IONOSPHERE

MIT Haystack

Kathryn Haughn

Credit: John Emmert/NRL

looking at the earth’s atmosphere earth’s protective bubble nasa accessed via wikipedia

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