How Are Cirrostratus Clouds Formed

Cirrostratus are sheet-like, high-level clouds composed of ice crystals. … These high-level clouds typically form when a broad layer of air is lifted by large-scale convergence. Photograph by: Rauber. Sometimes the only indication of their presence is given by an observed halo around the sun or moon.

Where are cirrostratus clouds formed?

Cirrostratus is usually located above 5.5 km (18,000 ft). Its presence indicates a large amount of moisture in the upper troposphere. Clouds resembling cirrostratus occasionally form in polar regions of the lower stratosphere.

What causes cirrocumulus clouds?

Cirrocumulus cloudlets are usually made up of both ice and ‘supercooled’ water. … They form when turbulent vertical currents meet a cirrus layer, creating the puffy cumulus shape. Cirrocumulus clouds can also form through contrails, the vapour trails left by planes as they fly through a dry upper troposphere.