Ice cloud

{{Short description|Atmospheric phenomenon}}

An ice cloud is a colloid of ice particles dispersed in air. The term has been used to refer to clouds of both water ice and carbon dioxide ice on Mars.

{{cite web |url=http://www.esa.int/esaCP/SEM1DV3MDAF_index_0.html |title=ESA Portal - Ice clouds put Mars in the shade |publisher=European Space Agency |date=16 January 2008 |accessdate=2009-12-20 }} Such clouds can be sufficiently large and dense to cast shadows on the Martian surface.

Cirrus and noctilucent clouds on Earth contain ice particles.{{cite web |url=http://www.projects.eu.com/news/new_satellite_to_measure_ice_cloud_particles_could_provide_valuable_new_climate_data |title=New satellite to measure ice cloud particles could provide valuable new climate data |date=December 8, 2009 |author=Tom Freeman|accessdate=2009-12-20 }}