Cadet Competition Written Practice Exam

Which type of cloud is found very high in the sky and mainly composed of ice crystals?

1. Stratus

2. Cumulus

3. Cirrus

4. Nimbus

The correct answer is: Cirrus

Cirrus clouds are characterized by their high altitude, typically forming above 20,000 feet in the atmosphere. They appear wispy and thin, resembling delicate strands or feathers due to their composition primarily of ice crystals, which form in cold atmospheric conditions. The presence of these ice crystals is a key distinguishing feature, as they reflect sunlight in a way that can give them a bright white appearance. In contrast, stratus clouds are low, uniform clouds that often cover the sky like a blanket, while cumulus clouds are puffy and have a more vertical structure, forming at lower altitudes and typically indicating fair weather. Nimbus refers to clouds that produce precipitation, such as rain or snow, and can encompass various types of clouds but does not specifically indicate a high-altitude cloud type. Thus, the choice of cirrus clouds aligns perfectly with the criteria of being high in the sky and primarily composed of ice crystals.