Science Final Exam Atmosphere Directed Readings
What is the life process by which plants and animals give off water vapor?
transpiration
It can be said that atmospheric pressure decreases as altitude
increases
the lower region of the thermosphere
ionosphere
Because the pull of gravity is not as strong at higher altitudes, the air molecules there are farther apart and exert
less pressure
Nitrogen is removed from the air primarily by
nitrogen-fixing bacteria
In addition to containing gaseous elements and compounds, the atmosphere carries various kinds of tiny solid particles such as dust and
pollen
What are three factors that affect the percentage of water vapor in the air?
day, location and season
The pressure of the atmosphere is exerted
equally in all directions
The most abundant elements in air include all of the following gases EXCEPT
Hydrogen
Explain why the temperature in the troposphere decreases as altitude increases.
It is heated below by thermal energy
How do large particles in the atmosphere differ from small particles?
Large particles remain in the atmosphere briefly while tiny particles can remain suspended for months or years.
the layer of atmosphere between the troposphere and the mesosphere, in which temperature increases as altitude increases
Stratosphere
Besides altitude, what are two other factors that cause atmospheric pressure to change?
Temperature and the amount of water vapor
What percentage of water is in dry air?
1%
Describe the four steps of the nitrogen cycle.
1. Nitrogen-fixing bacteria in soil change N2 into nitrogen compounds. 2. Nitrogen compounds in plants are consumed by animals 3. Nitrogen compounds return to the soil in wastes. 4. Decay and processes in the soil return N2 to the atmosphere.
How is water vapor removed as it enters the atmosphere?
condensation and precipitation
How do fossil fuels cause air pollution?
As fossil fuels (coal and petroleum) burn, they may release harmful chemicals such as sulfur dioxide gas, hydrocarbons, nitrogen oxides, carbon monoxide and lead into the air.
The pressure exerted on a surface by the atmosphere is called
Atmospheric pressure
phenomena caused by interactions between solar radiation and the ionosphere
Auroras
an instrument used to measure atmospheric pressure
Barometer
the region above the ionosphere, where Earth's atmosphere blends into the almost complete vacuum of space
Exosphere
What holds the gases of the atmosphere near Earth's surface?
Gravity
Identify six ways oxygen is removed from the atmosphere.
1. animals 4. fires 2. bacteria 5. burning of fuels 3. plants 6. weathering of some rocks
List seven different particulates.
1. volcanic dust 2. ash from fires 3. microscopic organisms 4.mineral particles 5. pollen 6. salt particles 7. soil
Describe four common sources of particulates
1. volcanoes 3. plants 2. tornadoes 4. ocean
What percentage of Earth's atmosphere is made up of oxygen?
21%
What percentage of water is in moist air?
4%
How much of Earth's atmosphere is composed of nitrogen?
78%
The composition of air is approximately the same all over Earth up to an altitude of about
80 km
How much of the total mass of the atmosphere does gravity keep within 32 km of Earth's surface?
99%
What is smog?
A combination of smoke and fog.
Is the current oxygen content of the atmosphere lower, higher, or about the same as it was millions of years ago? Explain your answer.
About the same. The amount of oxygen produced by plants equals the amount consumed by all animal life processes so it remains the same.
What purpose does the ozone layer serve?
Absorbs harmful ultraviolet radiation from the sun.
instrument that measures atmospheric pressure; changes in atmospheric pressure cause the sides of a sealed metal container to bend inward or bulge out
Altimeter
an aneroid barometer that registers altitude above sea level rather than air pressure
Aneroid barometer
What is an air pollutant?
Any substance in the atmosphere that is harmful to living things.
instrument that measures atmospheric pressure using a column of liquid mercury
Mecurial barometer
upper boundary of the mesosphere
Mesopause
the coldest layer of the atmosphere, between the stratosphere and the thermosphere, in which temperature decreases as altitude increases
Mesophere
Why does temperature begin to increase in the upper stratosphere?
Nitrogen and oxygen atoms receive radiation
The process by which nitrogen moves from air to the soil and then to plants and animals and eventually returns to the air is called the
Nitrogen cycle
What are two important functions of Earth's atmosphere?
Protect Earth's surface from the sun's radiation and help regulate the temperature of Earth's surface.
1 atmosphere; the average atmospheric pressure at sea level, equalling 760 mm of mercury or 1,000 millibars
Standard atmospheric pressure
upper boundary of the stratosphere
Stratopause
Define atmosphere
The layer of gases that surround the Earth. It is made up of chemical elements and compounds commonly called air.
What is a temperature inversion?
The layering of warm air on cool air. The warm air traps the cool air.
In general, what happens to atmospheric pressure at sea level when the temperature increases?
The pressure decreases
In Earth's atmosphere, what causes the distinctive pattern of temperature changes with increasing altitude?
The temperature differences result from how solar energy is absorbed as it moves through the atmosphere,
the uppermost layer of atmosphere, in which temperature increases as altitude increases
Thermosphere
Describe the effect of chlorofluorocarbons (CFCs) on the ozone layer
They have caused the ozone to weaken in some areas.
What are particulates?
Tiny solid particles
the upper boundary of the troposphere
Tropopause
the lowest layer of the atmosphere, in which temperature drops at a constant rate as altitude increases
Troposphere
What is ozone? How does it differ from oxygen?
Upper atmosphere called the ozone layer. It has 3 molecules instead of 2
Why is air that contains a lot of water vapor less dense than drier air?
Water vapor has less mass than oxygen and nitrogen.
Explain how oxygen is returned to the atmosphere.
a process called photosynthesis - where plants use sunlight, water and carbon dioxide to make their own food and release oxygen as a byproduct.
What three units do meteorologists use to measure atmospheric pressure?
atmospheres (atm) millimeters or inches of mercury Millibars (mb)
Explain why the temperature in the thermosphere steadily rises.
because nitrogen and oxygen atoms absorb radiation
As water evaporates from oceans, lakes, streams, and soil, it enters air as
water vapor
The two most abundant compounds in air are the gases carbon dioxide and
water vapor