Clouds
It is well known that our planet is becoming a
warmer place right now. However, what scientists find really strange is that
higher levels in the atmosphere stay cool while the Earth's surface warms.
Clouds are probably responsible for this trend. "A systematic change in global cloud cover will change the atmospheric heating profile," said Fangqun Yu, author of a new study. High clouds reflect sunlight and low clouds retain surface energy, so, increases in amounts of thick, low clouds can warm the surface of the Earth, but not higher levels in the atmosphere.
How could the worldwide cloud cover change? Cosmic rays may be to blame for changes in the patterns of cloudiness, warming Earth's surface by generating a blanket of low, thick clouds. More cosmic rays, increases the number of low clouds that warm the surface. Additionally, greenhouse gasses boost the impact of cosmic rays. This means that as our pollution sends more greenhouse gasses into the atmosphere, cosmic rays are able to create even more low clouds.
Clouds can come in all sizes and shapes, and can form near the ground or high in the atmosphere. Clouds are groups of tiny water droplets or ice crystals in the sky. They are associated with different kinds of precipitation depending on the atmosphere's temperature. Cloud types are classified by height and appearance. The shape depends on the way the air moves around it. If air moves horizontally, clouds form in layers. However, clouds grow upward if air movement is vertical.
At any given time, clouds cover about 50% of the Earth. We would not have rain, thunderstorms, rainbows or snow without clouds. The atmosphere would be quite boring if the sky was always clear.
Answer the following:
1 What are clouds made of?
2 Can you name some different types of clouds?