Quote:
Learning Goal: To understand data that lend strong support to the idea that human activity may cause global warming.
Introduction. The graphs display real data on global average temperature and carbon dioxide (CO2) concentration. The more recent data (shown in the zoomed-out graph on the right) come from direct CO2 measurements (made at Mauna Loa). Most of the earlier data are based on studies of air bubbles trapped in Antarctic ice core samples. The carbon dioxide concentration is measured in parts per million, which is the number of CO2 molecules among every million air molecules.
Part A -
The average temperature over the past 1000 years has been about 15^C. From the graphs, you can conclude that Earth's average temperature during the past 400,000 years has __________.
-varied between about 7^C and 19^C
-varied between about -10^C and +4^C
-stayed remarkable steady, never varying by more than about 2^C
-never been as high as it is today
The zero level on the graph represents the 15^C average temperature over the past millennium, so the peaks near +4 on the graph represent a temperature of about 15^C + 4^C = 19^C and the troughs near -8 represent 15^C - 8^C = 7^C.
Part B
On the graphs shown, you can identify an ice age by looking for __________.
-a peak on the temperature graph
-a place on the temperature graph where the temperature curve falls steeply
-a trough (bottom of a dip) on the temperature graph
-a trough (bottom of a dip) on the carbon dioxide graph
The graph shows that one ice age ended only about 10,000 years ago, and there have been numerous other ice ages during the past 400,000 years.
Part C
Notice that the peaks and troughs on the temperature graph occur at the about the same times as peaks and troughs on the carbon dioxide graph. What can we infer from this fact alone?
-Higher carbon dioxide concentrations cause higher global average temperatures.
-The carbon dioxide concentration is inversely related to the global average temperature.
-There is a correlation between the carbon dioxide concentration and the global average temperature.
-Higher global average temperatures cause higher carbon dioxide concentrations.
A correlation means that two things go up and down together. In this case, there is a correlation between the temperature and the carbon dioxide concentration because both were generally high at the same times in the past and low at the same times in the past.
Part D
Although the data show only a correlation between the carbon dioxide concentration and the global average temperature, there are other reasons to think that a rise in the carbon dioxide concentration actually causes a rise in the global average temperature. All of the following statements are true. Which statements lend support to the idea that carbon dioxide is a cause of planetary warming?
Check all that apply.
-Models of the greenhouse effect successfully predict the temperatures of Venus and Mars from their atmospheric carbon dioxide amounts.
-We understand the physical mechanism of the greenhouse effect, through which carbon dioxide can increase a planet's temperature.
-Models of Earth's climate that include recent increases in the carbon dioxide concentration match observed temperature increases better than those that do not include it.
-Isotope ratios in atmospheric carbon dioxide show that much of the carbon dioxide in Earth's atmosphere today comes from the burning of fossil fuels.
Together, the success of the models and our clear understanding of the mechanism of the greenhouse effect leave little room for doubt that carbon dioxide is indeed a cause of higher temperatures on a planet.
Part E
Based on the evidence that atmospheric carbon dioxide is a cause of planetary warming, what aspect of the graphs should most concern us?
-The carbon dioxide concentration today is significantly higher than at any time in the past 400,000 years and is rapidly rising.
-Earth's past carbon dioxide concentration rises and falls naturally.
-Earth's past temperature rises and falls naturally.
Therefore, if past trends continue, we would expect Earth's temperature to rise substantially as a result of this increase in the carbon dioxide concentration.
Part F
Make a prediction: If the rise in carbon dioxide concentration continues at its current pace, the concentration in the year 2037 will be about _____ parts per million.
-330
-390
-430
-510
Introduction. The graphs display real data on global average temperature and carbon dioxide (CO2) concentration. The more recent data (shown in the zoomed-out graph on the right) come from direct CO2 measurements (made at Mauna Loa). Most of the earlier data are based on studies of air bubbles trapped in Antarctic ice core samples. The carbon dioxide concentration is measured in parts per million, which is the number of CO2 molecules among every million air molecules.
Part A -
The average temperature over the past 1000 years has been about 15^C. From the graphs, you can conclude that Earth's average temperature during the past 400,000 years has __________.
-varied between about 7^C and 19^C
-varied between about -10^C and +4^C
-stayed remarkable steady, never varying by more than about 2^C
-never been as high as it is today
The zero level on the graph represents the 15^C average temperature over the past millennium, so the peaks near +4 on the graph represent a temperature of about 15^C + 4^C = 19^C and the troughs near -8 represent 15^C - 8^C = 7^C.
Part B
On the graphs shown, you can identify an ice age by looking for __________.
-a peak on the temperature graph
-a place on the temperature graph where the temperature curve falls steeply
-a trough (bottom of a dip) on the temperature graph
-a trough (bottom of a dip) on the carbon dioxide graph
The graph shows that one ice age ended only about 10,000 years ago, and there have been numerous other ice ages during the past 400,000 years.
Part C
Notice that the peaks and troughs on the temperature graph occur at the about the same times as peaks and troughs on the carbon dioxide graph. What can we infer from this fact alone?
-Higher carbon dioxide concentrations cause higher global average temperatures.
-The carbon dioxide concentration is inversely related to the global average temperature.
-There is a correlation between the carbon dioxide concentration and the global average temperature.
-Higher global average temperatures cause higher carbon dioxide concentrations.
A correlation means that two things go up and down together. In this case, there is a correlation between the temperature and the carbon dioxide concentration because both were generally high at the same times in the past and low at the same times in the past.
Part D
Although the data show only a correlation between the carbon dioxide concentration and the global average temperature, there are other reasons to think that a rise in the carbon dioxide concentration actually causes a rise in the global average temperature. All of the following statements are true. Which statements lend support to the idea that carbon dioxide is a cause of planetary warming?
Check all that apply.
-Models of the greenhouse effect successfully predict the temperatures of Venus and Mars from their atmospheric carbon dioxide amounts.
-We understand the physical mechanism of the greenhouse effect, through which carbon dioxide can increase a planet's temperature.
-Models of Earth's climate that include recent increases in the carbon dioxide concentration match observed temperature increases better than those that do not include it.
-Isotope ratios in atmospheric carbon dioxide show that much of the carbon dioxide in Earth's atmosphere today comes from the burning of fossil fuels.
Together, the success of the models and our clear understanding of the mechanism of the greenhouse effect leave little room for doubt that carbon dioxide is indeed a cause of higher temperatures on a planet.
Part E
Based on the evidence that atmospheric carbon dioxide is a cause of planetary warming, what aspect of the graphs should most concern us?
-The carbon dioxide concentration today is significantly higher than at any time in the past 400,000 years and is rapidly rising.
-Earth's past carbon dioxide concentration rises and falls naturally.
-Earth's past temperature rises and falls naturally.
Therefore, if past trends continue, we would expect Earth's temperature to rise substantially as a result of this increase in the carbon dioxide concentration.
Part F
Make a prediction: If the rise in carbon dioxide concentration continues at its current pace, the concentration in the year 2037 will be about _____ parts per million.
-330
-390
-430
-510
Edited, Oct 13th 2009 6:51pm by AshOnMyTomatoes
