Name: ____________________________________
Class: _____________
Date: _____________
Self Assessment: Changes in Earth's Climate over Time
1. Evidence of an ice age during the Paleozoic era, around 250 million years ago, has been found in India,
Africa, Australia, and South America. Which factor could explain how glaciers could have existed in these
locales, but not in Eurasia or North America, at the time?
a) Icebergs from Antarctica drifted to all these continents, bringing temporary cold and specimens from a
much colder climate.
b) The drift of the continents since then has since brought these areas away from the South Pole.
c) Variations in Earth's orbit (eccentricity, obliquity, and precession) produced a period of global cooling.
d) Changes in oceanic circulation caused cooling of these areas and altered the transport of heat and
moisture between water and land.
2. A major change in climate that resulted in a trend toward global cooling would most likely have which
short term result?
a) major flooding of coastlines
b) overall increase in cloud cover
c) drop in global sea levels
d) global mean precipitation increase
3. Under balanced conditions, the amount of solar radiation absorbed by Earth's atmosphere, oceans, and
landforms is approximately the same as the amount of energy reflected back into space. An increase in what
would affect this balance enough to cause global cooling?
a) the amount of landmass covered in ice and snow
b) the amount of carbon dioxide in the atmosphere
c) the speed of wind currents
d) the number of sunspots
4. A cross section of a tree trunk shows thin rings at the center that become wider toward the perimeter.
What generalization can be made about the climate of this tree's environment?
a) It was once dry, but now it is wet.
b) It was once cold, but now it is warm.
c) It was once wet, but now it is dry.
d) It was once warm, but now it is cold.
PAGE 1
Name: ____________________________________
Class: _____________
Date: _____________
Self Assessment: Changes in Earth's Climate over Time
5. Which factor could NOT cause a change in the amount of insolation, or solar radiation received by Earth,
that would significantly affect global climate?
a) variation in the number and frequency of sunspots
b) variation in the frequency of solar eclipses
c) variation in the angle of tilt of Earth's axis
d) variation in the shape of Earth's orbit around the Sun
6. El Niño is an abnormal climate event caused by changes in wind currents in the western Pacific. El Niño
occurs every 2 to 7 years, and can have a disastrous impact on the oceans and nearby land. The example of
El Niño illustrates the truth of which statement?
a) Scientists fully understand the effects of short term climate changes.
b) A change in one weather condition can affect others in a given region.
c) Changes in wind currents can create harsh conditions in isolated areas.
d) Ocean currents are caused by temperature differences in the water.
7. Spokane, Washington has a cool climate and receives little rainfall. Phoenix, Arizona has a hot climate and
also receives little rainfall. How would increased rainfall relatively affect Spokane and Phoenix's short term climates?
a) Spokane's climate would be more immediately affected.
b) Spokane's and Phoenix's climates would be affected the same.
c) Neither Spokane's nor Phoenix's climate would be affected.
d) Phoenix's climate would be more immediately affected.
8. Which factor is most likely NOT a major cause of long term climate change?
a) changes in the composition of Earth's atmosphere
b) eruption of volcanoes
c) motions of the Earth's tectonic plates
d) variations in the amount of solar energy received by Earth
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Name: ____________________________________
Class: _____________
Date: _____________
Self Assessment: Changes in Earth's Climate over Time
9. The most recent ice age ended about 10,500 years ago. Why was the average sea level during that ice age
much lower than it is today?
a) Much of the water was frozen into huge ice sheets.
b) Oceans covered a greater percentage of Earth's surface than they do today.
c) The water was funneled inland and into lakes.
d) Large amounts of water evaporated.
10. Which fact expresses a difference between the current warming trend and previous changes in the global
climate?
a) Earth has received increasing amounts of solar energy in the last few years.
b) Earth is at a time in its orbit when it is relatively close to the sun.
c) Since 1860, the atmosphere's CO 2 content has increased 25%.
d) Sea levels have risen by 10 to 20 centimeters over the last 100 years.
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ANSWER KEY
1. b
2. c
3. a
4. a
5. b
6. b
ANSWER KEY Page 1
7. a
8. b
9. a
10. c