2. Atmosphere
❖atmos meaning vapor and sphaira meaning sphere
❖a sphere of vapor, or a gaseous envelope, surrounding a sphere or globe
Divisions of the Atmosphere
3. Troposphere
❖“Tropos” means change
❖Closest to the surface of Earth
❖This layer has the air we breathe
and the clouds in the sky.
❖between 5 and 9 miles (8 and 14
kilometers)
❖thinnest at the North and South
Pole
❖temperature decreases with height
to about –55°C or –60°C (about
6.5°C per 1,000 meters of altitude)
❖78% nitrogen, 21% oxygen, 1%
argon, water vapor, and carbon
dioxide
4. Stratosphere
❖“Strat” means layer
❖There are no storms or turbulence
here to mix up the air so cold,
heavy air is at the bottom and
warm, light air is at the top
❖22 miles (35 kilometers) thick
❖Where to find ozone layer
❖Ozone layer helps protect us from
ultraviolet radiation (UV) from the
sun. In fact, the ozone layer
absorbs most of the UV radiation
the sun sends to us
5. Mesosphere
❖“Meso” means middle
❖highest layer of the atmosphere in
which the gases are all mixed up
rather than being layered by their
mass
❖22 miles (35 kilometers) thick
❖Where meteors burn up due to
friction from gases
6. Thermosphere
❖“Thermo” means heat
❖Temperature can reach up to 4,500 degrees
Fahrenheit
❖No enough gas molecules for heat to
transfer or sound to travel
❖about 319 miles (513 kilometers) thick
❖home to the International Space Station as
it orbits Earth
❖where low Earth orbit satellites can be
found
7. Exosphere
❖“Exo” means outside
❖separates the rest of the
atmosphere from outer space
❖about 6,200 miles (10,000
kilometers) thick
❖has gases like hydrogen and
helium
❖Extremely cold
8. Ionosphere
❖overlaps
the mesosphere, thermosphere,
and exosphere
❖very active part of the atmosphere,
and it grows and shrinks depending on
the energy it absorbs from the sun
❖gases in these layers are excited by
solar radiation to form “ions,” which
have an electrical charge
❖charged particles are affected by the
magnetic fields of both Earth and the
sun
❖where auroras happen
Exosphere
9.
10. Hydrosphere
• The hydrosphere consists of the
Earth’s water resources: oceans,
lakes, rivers, streams, groundwater,
and glaciers
• 97.5% of water on Earth is salt water
• Only 2.5% is freshwater
¾ of our planet is water
BLUE PLANET - Earth
11. Structure of Hydrosphere
• Marine/Ocean: 97.5%
• Fresh water distribution:
• Ice: 2.3%
• Groundwater: 0.4%
• Surface Fresh Water: 0.05%
• Atmosphere and soil: 0.05%
River
Pond
Streams
Lake
Ocean
Iceberg
Glacier
12. Surface Freshwater
River
Pond
Streams
Lake
Ponds: Shallow enough for sunlight to
hit bottom (allowing plants to grow
there)
Lakes (and large ponds): Too deep for
plants to grow on the bottom, so algae
grows and floats on top of water.
Streams are bodies of running
water (as a river or brook) flowing
on the earth
Rivers are large, natural stream of
flowing water
13. Surface Freshwater
River basin – the land that water
flows across or under on its way to a
river and out to an estuary or to the
ocean
Watershed – used to describe a
smaller area of land that drains to a
smaller stream, lake or wetland
14. Ground water
• The water found in cracks
and pores in sand, gravel and
rocks below the earth’s
surface
• Aquifer – porous rock layer
underground that is a
reservoir for water
