The correct choice is B) Changes in Cloud Cover
Explanation:
In recent times, the cloud factor has become the most worrying development in the science of climate change. Recent studies suggest that the ability of clouds to keep us cool could be drastically reduced as the world warms — pushing global heating into overdrive.
There are two types of clouds which help to cool the Earth.
Marine stratus and Stratocumulus clouds.
Reflecting 30 to 60 percent of the solar radiation that hits them back into space, they provide shade to approximately one fifth of the oceans. This reduced the amount of radiation reaching us by between 4 and 7 percent.
Lately, however, it is beginning to look like the clouds could become thinner or burn off entirely as the world gets warmer. If it does, we will be left with more desert like skies through which the sun may add a degree Celsius or more to global warming.
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