title: Laser-induced plasma cloud interaction and ice multiplication under cirrus cloud conditions.
abstract: Potential impacts of lightning-induced plasma on cloud ice formation and precipitation have been a subject of debate for decades. Here, we report on the interaction of laser-generated plasma channels with water and ice clouds observed in a large cloud simulation chamber. Under the conditions of a typical storm cloud, in which ice and supercooled water coexist, no direct influence of the plasma channels on ice formation or precipitation processes could be detected. Under conditions typical for thin cirrus ice clouds, however, the plasma channels induced a surprisingly strong effect of ice multiplication. Within a few minutes, the laser action led to a strong enhancement of the total ice particle number density in the chamber by up to a factor of 100, even though only a 10(-9) fraction of the chamber volume was exposed to the plasma channels. The newly formed ice particles quickly reduced the water vapor pressure to ice saturation, thereby increasing the cloud optical thickness by up to three orders of magnitude. A model relying on the complete vaporization of ice particles in the laser filament and the condensation of the resulting water vapor on plasma ions reproduces our experimental findings. This surprising effect might open new perspectives for remote sensing of water vapor and ice in the upper troposphere.
authors.affiliation: Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany. thomas.leisner@kit.edu
authors.forename: Thomas
authors.initials: T
authors.lastname: Leisner
authors.forename: Denis
authors.initials: D
authors.lastname: Duft
authors.forename: Ottmar
authors.initials: O
authors.lastname: Möhler
authors.forename: Harald
authors.initials: H
authors.lastname: Saathoff
authors.forename: Martin
authors.initials: M
authors.lastname: Schnaiter
authors.forename: Stefano
authors.initials: S
authors.lastname: Henin
authors.forename: Kamil
authors.initials: K
authors.lastname: Stelmaszczyk
authors.forename: Massimo
authors.initials: M
authors.lastname: Petrarca
authors.forename: Raphaëlle
authors.initials: R
authors.lastname: Delagrange
authors.forename: Zuoqiang
authors.initials: Z
authors.lastname: Hao
authors.forename: Johannes
authors.initials: J
authors.lastname: Lüder
authors.forename: Yannick
authors.initials: Y
authors.lastname: Petit
authors.forename: Philipp
authors.initials: P
authors.lastname: Rohwetter
authors.forename: Jérôme
authors.initials: J
authors.lastname: Kasparian
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Wolf
authors.forename: Ludger
authors.initials: L
authors.lastname: Wöste
mesh_terms: D000336:Aerosols / Q000737:chemistry; D001272:Atmosphere / Q000737:chemistry*; D001273:Atmosphere Exposure Chambers; D002980:Climate; D006813:Humidity; D007053:Ice / Q000032:analysis*; D007834:Lasers; D008030:Lightning; D008962:Models, Theoretical; D017711:Nonlinear Dynamics; D055095:Optics and Photonics / Q000295:instrumentation; D058998:Remote Sensing Technology / Q000379:methods; D013227:Steam / Q000032:analysis*; D013696:Temperature
chemical_list: D000336:Aerosols; D007053:Ice; D013227:Steam
keywords: lightning; nonlinear optics; secondary ice