Earth's Systems and Resources - Environmental Science - page 31

A. Volcanoes erupt.
B. Magma pushes through the Earth's crust at the mid-ocean ridge and hardens.
C. Plates continually move, disrupting the magma.
D. Oceanic plates are subducted at plate boundaries.
E. Heated ocean water rises and sinks at the mid-ocean ridge.
14. In which way do volcanic gases NOT temporarily affect the atmosphere?
A. Ozone is broken down when reactions occur with HCl or SO 2 .
B. Gases ultimately lower the mean global temperature.
C. Acid rain is reduced.
D. The temperature of the planet increases over time.
E. Smog is created regionally.
15. Three convection currents impact atmospheric circulation: the Ferrel, Hadley, and polar air circulation
cells. Which of the following is NOT true of these convection cells?
A. The polar air circulation cells are characterized by two major biomes, tundra and taiga.
B. Both the Hadley and polar circulation cells influence the Ferrel air circulation cells.
C. Two distinct regions—the equatorial region of high humidity and heavy rain and the subtropical re-
gion of low humidity, few clouds, and high water evaporation—characterize the Hadley air circula-
tion cells.
D. The three types of convection cells occur only in the northern hemisphere.
E. Ferrel circulation cells are defined by the four traditional seasons—spring, summer, fall, and winter.
Answers
1. C Earthquakes, volcanoes, and the formation of mountain ranges take place at plate boundaries and oc-
cur due to the continual movement of the tectonic plates. Plates can converge, diverge, or slide past one
another, leading to geologic activity and the creation of geologic structures.
2. A Sulfur dioxide chemically reacts with hydrogen and oxygen to form H 2 SO 4 , which forms acid and in-
creases the rate of ozone depletion.
3. C Hydrogen fluoride can cause bone deterioration, poisoning of animals, and acid rain. Excess fluorine
in animals can poison animals and can lead to fluorosis, which deteriorates bones and may lead to
death.
4. B Carbon dioxide is denser than air, so excess amounts can create pockets of CO 2 close to the ground in
low-lying areas. Ultimately, this could lead to asphyxiation and death.
5. C Summer occurs when the sun's rays hit the Earth's surface at the most direct angles. Summer is also
marked by the longest daylight hours.
6. E Of the Earth's water, 97.5 percent is held in oceans, while 2.5 percent is freshwater.
7. B Ocean currents are impacted by the movement of wind, the heating of the ocean's surface by the sun,
the Coriolis effect, and density differences in the water.
8. B The A horizon is considered the topsoil and is an organic and inorganic mix of materials.