Question 1

Which of the following conditions likely caused the "year without a summer" in 1816?

Accepted Answer

A) a dust cloud produced when a meteorite collided with the Earth 
B) deforestation 
C) particulate matter and gases from volcanoes 
D) soot from coal fires

Question 2

Climatic models predict that the concentration of a certain gas must increase in the atmosphere for CO2 to produce a global warming of between 2°C and 5°C. According to this prediction, which of the following gases must increase?

Accepted Answer

A) chlorofluorocarbons (CFCs) 
B) water vapour (H2O) 
C) sulfur dioxide (SO2) 
D) ozone (O3)

Question 3

Which of the following statements represents the global climate throughout much of the Earth's history?

Accepted Answer

A) It was likely warmer than it is today. 
B) It was likely about the same temperature as it is today. 
C) It was likely colder than it is today. 
D) It was likely more variable than it is today.

Question 4

Which of the following reasons for climatic change is proposed by the Milankovitch theory?

Accepted Answer

A) volcanic eruptions 
B) changing levels of CO2 in the Earth's atmosphere 
C) particles suspended in the Earth's atmosphere 
D) variations in the Earth's orbit as it travels through space

Question 5

Which of the following patterns refers to a quasi-biennial oscillation?

Accepted Answer

A) reversal of stratospheric winds above the tropics 
B) 2 million-year cycle of ice advances and retreats 
C) cycle of increase and decrease in carbon dioxide concentrations 
D) 22-year cycle of sunspots

Question 6

In addition to carbon dioxide, what other gases may contribute to the problem of global warming? Why might global warming lead to an increase in global cloudiness? What possible effects would an increase in cloudiness have on global warming?

Accepted Answer

The answer of In addition to carbon dioxide, what other...

Question 7

Which of the following changes to the sun's total energy output will likely occur as the number of sunspots increases?

Accepted Answer

A) slight decrease 
B) no change 
C) alternately increase and decrease above average values 
D) slight increase

Question 8

Which of the following refers to the precession of the equinox?

Accepted Answer

A) changes in the seasons, especially from winter to summer 
B) changes in the tilt of the Earth's axis as it orbits the sun 
C) the wobble of the Earth on its axis 
D) changes in the shape of the Earth's orbit as the Earth revolves around the sun

Question 9

Which of the following describes the apparent change in the average global temperatures over the past 100 years or so?

Accepted Answer

A) They have increased slightly. 
B) They have fluctuated widely but shown no overall change. 
C) They have decreased slightly. 
D) They have remained constant.

Question 10

Consider the ratio of oxygen 18 to oxygen 16 in the shells of organisms that lived in the sea during the geologic past. Which of the following describes the relationship between this ratio and the climate at that time?

Accepted Answer

A) the higher the ratio, the drier climate at that time 
B) the higher the ratio, the wetter climate at that time 
C) the higher the ratio, the colder climate at that time 
D) the higher the ratio, the warmer climate at that time

Question 11

Where is the Sahel located? Is this a region of scarce, variable, or abundant rainfall? Describe the biogeophysical feedback mechanism whereby a reduction in surface vegetation might cause a reduction in precipitation amounts.

Accepted Answer

The answer of Where is the Sahel located? Is this...

Question 12

Which of the following statements describes the overall effect of clouds?

Accepted Answer

A) They have a net warming effect on climate. 
B) They have a net cooling effect on climate. 
C) They are the most important feature in determining climate. 
D) They have no net effect on climate.

Question 13

Discuss some of the challenges that climatologists face when attempting to reconstruct the climate of the past.

Accepted Answer

The answer of Discuss some of the challenges that climatologists...

Question 14

Describe some of the techniques used to infer past climates. About how far into the past are these different methods able to reconstruct past climatic conditions?

Accepted Answer

The answer of Describe some of the techniques used to...

Question 15

Assume that you have 100 years of continuous temperature records from your local weather service office. Discuss some of the difficulties you might have trying to determine whether average temperatures have increased during this period.

Accepted Answer

The answer of Assume that you have 100 years of...

Question 16

If the Earth was in a warming trend, which of the following processes would most likely act as a negative feedback mechanism?

Accepted Answer

A) decreasing the amount of cloud cover around the Earth 
B) increasing the carbon dioxide content of the air 
C) increasing the snow cover around the Earth 
D) increasing the water vapour content of the air

Question 17

What is meant by the term positive feedback? What role could positive feedback play in the atmospheric greenhouse effect? Would this enhance or reduce global warming? What is an example of a "negative feedback" mechanism?

Accepted Answer

The answer of What is meant by the term positive...

Question 18

Which of the following conditions most likely produces warming at the Earth's surface?

Accepted Answer

A) an increase in low-level global cloudiness 
B) a decrease in energy output of the sun 
C) an increase in high-level global cloud cover 
D) an increase in sulphur-rich particles in the stratosphere

Question 19

Which of the following describes the Maunder Minimum?

Accepted Answer

A) It occurred during the Little Ice Age. 
B) There were many sunspots. 
C) It caused a significant change in the eccentricity of Earth's orbit. 
D) It has been studied by analysis of ice cores in Antarctica.

Question 20

In a warmer world, which of the following changes will likely happen to the growing season at higher latitudes?

Accepted Answer

A) The growing season will remain unchanged. 
B) The growing season will be shorter at first, but then will be longer. 
C) The growing season will be shorter. 
D) The growing season will be longer.

Exam 17: Earths Changing Climate