importance of the atmosphere

keeps earths temperature moderate

Along with the oceans, the atmosphere keeps Earths temperatures within an acceptable range. Without an atmo- sphere, Earths temperatures would be frigid at night and scorching during the day. If the 12-year-old in the scenario above asked why, she would find out. Greenhouse gases trap heat in the atmosphere. Important greenhouse gases include carbon dioxide, methane, water vapor, and ozone.

provides the substance for waves to travel through

The atmosphere is made of gases that take up space and transmit energy. Sound waves are among the types of energy that travel though the atmosphere. Without an atmosphere, we could not hear a single sound. Earth would be as silent as outer space (explosions in movies about space should be silent). Of course, no insect, bird, or airplane would be able to fly, because there would be no atmosphere to hold it up. Click image to the left or use the URL below. URL:

crucial part of the water cycle

As part of the hydrologic cycle, water spends a lot of time in the atmosphere, mostly as water vapor. The atmosphere is an important reservoir for water. Chlorophyll indicates the presence of photosynthesizing plants as does the veg- etation index.


ozone makes life on earth possible

Ozone is a molecule composed of three oxygen atoms, (O3 ). Ozone in the upper atmosphere absorbs high-energy ultraviolet (UV) radiation coming from the Sun. This protects living things on Earths surface from the Suns most harmful rays. Without ozone for protection, only the simplest life forms would be able to live on Earth. The highest concentration of ozone is in the ozone layer in the lower stratosphere.


In photosynthesis, plants use CO2 and create O2 . Photosynthesis is responsible for nearly all of the oxygen currently found in the atmosphere. The chemical reaction for photosynthesis is: 6CO2 + 6H2 O + solar energy C6 H12 O6 (sugar) + 6O2


By creating oxygen and food, plants have made an environment that is favorable for animals. In respiration, animals use oxygen to convert sugar into food energy they can use. Plants also go through respiration and consume some of the sugars they produce. The chemical reaction for respiration is: C6 H12 O6 + 6O2 6CO2 + 6H2 O + useable energy How is respiration similar to and different from photosynthesis? They are approximately the reverse of each other. In photosynthesis, CO2 is converted to O2 and in respiration, O2 is converted to CO2 (Figure 1.2).

what is the atmosphere

Earths atmosphere is a thin blanket of gases and tiny particles together called air. We are most aware of air when it moves and creates wind. Earths atmosphere, along with the abundant liquid water at Earths surface, are the keys to our planets unique place in the solar system. Much of what makes Earth exceptional depends on the atmosphere. For example, all living things need some of the gases in air for life support. Without an atmosphere, Earth would likely be just another lifeless rock. Lets consider some of the reasons we are lucky to have an atmosphere.

gases indispensable for life on earth

Without the atmosphere, Earth would look a lot more like the Moon. Atmospheric gases, especially carbon dioxide (CO2 ) and oxygen (O2 ), are extremely important for living organisms. How does the atmosphere make life possible? How does life alter the atmosphere? The composition of Earths atmosphere.


instructional diagrams

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the atmosphere is composed of 78% _ and 21% _.

a) carbon dioxide; oxygen

b) oxygen; nitrogen

c) nitrogen; carbon dioxide

-->  d) nitrogen; oxygen

photosynthesis helps plants create _ from _.

-->  a) food energy; solar energy

b) solar energy; food energy

c) sugar; carbon dioxide gas

d) carbon dioxide gas; sugar

the atmosphere is a reservoir for water.

-->  a) true

b) false

in space, no one can hear you scream, because there is not medium for the sound waves to travel through

-->  a) true

b) false

the ozone molecule is made of

a) two water molecules

-->  b) three oxygen atoms

c) one carbon dioxide molecule with a water molecule

d) two oxygen atoms with one water molecule

the red chlorophyll hotspots on the chlorophyll map are directly related to the excess nutrients in those areas.

-->  a) true

b) false

without oxygen in the atmosphere, there would be

a) no plants.

-->  b) no animals.

c) no plants or animals.

d) no difference in life forms.

what is the relationship between photosynthesis in plants and the respiration of animals?

-->  a) plants use co2 and produce o2; animals use o2 and produce co2.

b) plants use o2 and produce co2; animals use co2 and produce o2.

c) plants use nitrogen and produce water vapor; animals use water vapor and produce nitrogen.

d) plants use water vapor and produce nitrogen; animals use nitrogen and produce water vapor.

what would happen if there were no greenhouse gases in the atmosphere?

a) temperatures would be frigid all the time and the ice ages would return.

b) temperatures would be extremely hot all the time.

-->  c) temperatures would be frigid at night and scorching in the day.

d) ultraviolet radiation from the sun would fry all live on the surface.

how does the atmosphere protect us from the sun?

a) ozone in the lower atmosphere absorbs all wavelengths of electromagnetic radiation from the sun.

b) greenhouse gases in the atmosphere absorb solar radiation to block out the harmful rays.

c) greenhouse gases in the upper atmosphere absorb heat from the planet and block out harmful radiation.

-->  d) ozone in the upper atmosphere absorbs the highest energy ultraviolet radiation coming

diagram questions

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