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Laser vaporization of cirrus-like ice particles with secondary ice multiplication.

ABSTRACT: We investigate the interaction of ultrashort laser filaments with individual 90-μm ice particles, representative of cirrus particles. The ice particles fragment under laser illumination. By monitoring the evolution of the corresponding ice/vapor system at up to 140,000 frames per second over 30 ms, we conclude that a shockwave vaporization supersaturates the neighboring region relative to ice, allowing the nucleation and growth of new ice particles, supported by laser-induced plasma photochemistry. This process constitutes the first direct observation of filament-induced secondary ice multiplication, a process that strongly modifies the particle size distribution and, thus, the albedo of typical cirrus clouds.

SUBMITTER: Matthews M

PROVIDER: S-EPMC4928985 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Laser vaporization of cirrus-like ice particles with secondary ice multiplication.

Matthews Mary M Pomel François F Wender Christiane C Kiselev Alexei A Duft Denis D Kasparian Jérôme J Wolf Jean-Pierre JP Leisner Thomas T

Science advances 20160520 5

We investigate the interaction of ultrashort laser filaments with individual 90-μm ice particles, representative of cirrus particles. The ice particles fragment under laser illumination. By monitoring the evolution of the corresponding ice/vapor system at up to 140,000 frames per second over 30 ms, we conclude that a shockwave vaporization supersaturates the neighboring region relative to ice, allowing the nucleation and growth of new ice particles, supported by laser-induced plasma photochemist ...[more]

PMID: 27386537

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