CBSE Class 9 Social Science Atmosphere and Climate (Class 9 NCERT New) Quiz 7

1. Some human and natural activities cool Earth, while others cause average temperatures to increase. When all the different ways Earth's atmosphere is warmed and cooled are added up, the net effect currently is

A Earth's average atmospheric temperatures are warming B Earth's average atmospheric temperatures are fluctuating every few years, but generally are stable C Earth's average atmospheric temperatures are cooling

2. Even if we stop using fossil fuels immediately, Earth's atmosphere will continue to warm for a few more years. Why?

A fossil fuel emissions multiply in the presence of sunlight B chemical reactions from secondary pollutants will warm the atmosphere C the sun itself is emitting an increasing amount of radiation D there is a lag time between our emission of greenhouse gases and actual warming of Earth

3. Which of the following has been found to be true about where excess carbon dioxide from fossil fuel combustion is stored?

A most is stored in the atmosphere for a few decades then absorbed by the ocean B most is stored in the ocean for a few decades, then released to the atmosphere C most is stored in the atmosphere for centuries D most is stored in the ocean for centuries

4. Since the Industrial Revolution, scientists have known burning fossil fuels would add greenhouse gases to the atmosphere. What misconception caused them to conclude it would be harmless?

A they thought animals taking in carbon dioxide during respiration would compensate for the increase from fossil fuels B they thought the ocean would absorb all of the extra carbon dioxide being released C they thought forests would take in enough carbon dioxide to reduce the impact D they thought most of the carbon dioxide would be removed from the atmosphere as it interacted with exposed rocks

5. Rising sea levels are a result of

A increased amounts of precipitation B melting ice only C increased carbon dioxide levels in the ocean D melting ice and expansion of heated water

6. What causes Earth to have seasons?

A different areas of Earth are closer or further from the sun as it revolves throughout the year B Earth is tilted, causing some areas to be closer to the sun than others at various points in its revolution C some areas receive the sun's radiation at a more direct angle than others because the Earth is tilted D the planet is shaped like a slightly flattened beach ball (an oblate spheroid)

7. Which of the following best descries the approach scientists take to study climate change?

A Scientists only look at direct measurements being made today, because we cannot accurately estimate conditions from many years ago. B Scientists rely mainly on evidence from Earth's geologic history, because today's technology is not precise enough to give consistent readings. C Scientists measure atmospheric conditions around the world now and combine that information with indirect evidence gathered about past climates. D Scientists rely on modern data collection and computer models, which help predict possible changes to Earth's climate in the future, but past climates are not included in the models because they may not be accurate.

8. How is the ocean changing in response to climate change?

A it is becoming warmer and more acidic B it is becoming warmer and less acidic C it is becoming cooler and more acidic D it is becoming cooler and less acidic

9. Which of the following is not one of the impacts of climate change currently observed on Earth?

A more frequent outbreaks of disease and insect infestations in forests B saltwater intrusion into aquifers has increased due to sea levels decreasing C economic impacts due to storm damage and lower crop productivity D heat waves have caused more cases of heat stroke

10. What is the largest source of greenhouse gas emissions in the United States?

A fertilizer production B agriculture C industrial plants D electricity production