Exam 17: Earths Changing Climate

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

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?

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

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

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

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?

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

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

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

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?

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.

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

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

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?

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.

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

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?

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

Which of the following describes the Maunder Minimum?

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