多选题 The correlation between carbon dioxide and temperature throughout the Vostok record is consistent and predictable. The absolute temperature changes, however, are from 5 to 14 times greater than would be expected on the basis of carbon dioxide's own ability to absorb infrared radiation, or radiant heat. {{U}}This reaction suggests that, quite aside from changes in heat-trapping gases, commonly known as greenhouse gases, certain positive feedbacks are also amplifying the temperature change.{{/U}} Such feedbacks might involve ice on land and sea, clouds, or water vapor, which also absorb radiant heat.
The author mentions "certain positive feedbacks" in order to indicate that

• A. increased concentration of carbon dioxide in the Earth's atmosphere is responsible for global temperature increase.
• B. some climate simulation models have produced useful information.
• C. greenhouse gases alone do not account for global temperature increase.
• D. variables that benefit life are causing global temperature to increase.
• E. beneficial substances that are not heat-trapping gases and that contribute to global temperature increase have been found in the Vostok ice core.