An ice crystal halo display that contains several previously unknown halo phenomena was observed in Northern Chile. Analysis of computer simulations of the halos demonstrates that most of the new halo arcs in the display can be explained by the presence of airborne and preferentially oriented crystals of cubic ice. These observations therefore provide evidence of the existence of the cubic phase of ice in the Earth’s atmosphere.
© 2000 Optical Society of America
Marko Riikonen, Mika Sillanpää, Leena Virta, Daniel Sullivan, Jarmo Moilanen, and Ismo Luukkonen, "Halo Observations Provide Evidence of Airborne Cubic Ice in the Earth’s Atmosphere," Appl. Opt. 39, 6080-6085 (2000)