GRE Reading Comprehension
Home > GRE Test > GRE Reading Comprehension Questions
Next steps
- Use your browser's back button to return to your test results.
- Do more GRE Reading Comprehension Questions.
Source: CHP
The molecules of carbon dioxide in the Earth's atmosphere affect the heat balance of the Earth by acting as a one-way screen. Although these molecules allow radiation at visible wavelengths, where most of the energy of sunlight is concentrated, to pass through, they absorb some of the longer-wavelength, infrared emissions radiated from the Earth's surface, radiation that would otherwise be transmitted back into space. For the Earth to maintain a constant aver age temperature, such emissions from the planet must balance incoming solar radiation. If there were no car-bon dioxide in the atmosphere, heat would escape from the Earth much more easily. The surface temperature would be so much lower that the oceans might be a solid mass of ice.
Question List: 1 2
According to the passage, atmospheric carbon dioxide performs which of the following functions
- A absorbing radiation at visible wavelengths
- B absorbing outgoing radiation from the Earth
- C helping to retain heat near the Earth's surface