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Abstract. A new inlet for studying the aerosol particles andhydrometeor residuals that compose mixed-phase clouds – the phaSeseParation Inlet for Droplets icE residuals and inteRstitial aerosolparticles (SPIDER) – is described here. SPIDER combines a large pumpedcounterflow virtual impactor (L-PCVI), a flow tube evaporation chamber, anda pumped counterflow virtual impactor (PCVI) to separate droplets, icecrystals (∼3–25 µm), and interstitial aerosolparticles for simultaneous sampling. Laboratory verification tests of eachindividual component and the composite SPIDER system were conducted.Transmission efficiency, evaporation, and ice crystals' survival weredetermined to show the capability of the system. The experiments show theSPIDER system can separate distinct cloud elements and interstitial aerosolparticles for subsequent analysis. As a field instrument, SPIDER will helpexplore the properties of different cloud elements and interstitial aerosolparticles in mixed-phase clouds.
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High Supersaturation in the Wake of Falling Hydrometeors: Implications for Cloud Invigoration and Ice Nucleation
Abstract Aerosol particles, cloud droplets, and ice crystals, coupled through the supersaturation field, play an important role in the buoyancy and life cycle of convective clouds. This letter reports laboratory observations of copious cloud droplets and ice crystals formed in the wake of a warm, falling water drop, which is a laboratory surrogate for a relatively warm hydrometeor in atmospheric clouds, such as a graupel particle in the wet growth regime. Aerosols were activated in the regions of very high supersaturation due to mixing in the wake. A mechanism is explored for attaining very high supersaturations capable of activating significant fractions of the interstitial aerosols within the lifetime of a convective cloud. The latent heat released from the activation of interstitial aerosols and subsequent growth may provide an additional source of buoyancy for cloud invigoration and may lead to larger concentrations of ice crystals.
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- Award ID(s):
- 1754244
- PAR ID:
- 10447388
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 47
- Issue:
- 10
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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