Ice cloud


An ice cloud is a colloid of ice particles dispersed in air. Cirrus and noctilucent clouds on Earth contain ice particles. On Earth, ice clouds are distributed globally covering around 50% of the Earths surface. The term has been used to refer to clouds of both water ice and carbon dioxide ice on Mars. Such clouds can be sufficiently large and dense to cast shadows on the Martian surface.
Around the tropics at altitudes of 5 to 15 kilometers, the most frequently observed ice clouds are optically thin. Thicker ice clouds occur frequently in tropical convective areas and along storm tracks at midlatitudes.

Effects

Ice clouds play a crucial role in a variety of processes such as the heat balance of Earth and global water cycle.

Heat regulation

They play a crucial role in its radiation balance. They can cool the atmosphere by reflecting solar radiation back to space and warm it up by blocking outgoing thermal radiation. Their effects on the climate varies significantly depending on their location causing heating when in the upper troposphere of the tropics while causing strong cooling in lower altitudes.

Water cycle

They also play a crucial role in the global water cycle being involved in processes such as latent heat release, precipitation and radiative forcing.

Study

Despite their crucial importance to the energy balance of Earth, ice clouds remain poorly studied. Part of the difficulties of studying them is due to the many complexities and lathe variety of factors that influences them such as temperature, humidity, vertical wind and others. Several models have been made to accurately calculate the properties of ice clouds. However there are nanosatellites such as IceCube that are study the global atmospheric ice content and its effects on Earths climate. Other satellites such as CloudSat and the CALIPSO are used to study ice clouds.