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arXiv · 2210.15766

Enhancements in cloud condensation nuclei concentrations from turbulent fluctuations in supersaturation

Jesse C. Anderson·Payton Beeler·Mikhail Ovchinnikov·Will Cantrell·Steven Krueger·Raymond A. Shaw·Fan Yang·Laura Fierce
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Abstract

The effect of aerosol emissions on the properties and distribution of clouds is a large source of uncertainty in predictions of weather and climate. These aerosol-cloud interactions depend critically on the ability of aerosol particles to activate into cloud condensation nuclei (CCN). A key challenge in modeling CCN activation and the formation of cloud droplets is the representation of interactions between turbulence and cloud microphysics. Turbulent mixing leads to small-scale fluctuations of water vapor and temperature that are not resolved in large-scale atmospheric models. We used Lagrangian parcel simulations driven by a high-resolution Large Eddy Simulation of a convective cloud chamber to quantify the impact of these small-scale fluctuations on CCN activation. We show that small-scale fluctuations in environmental properties strongly enhance CCN activation, which suggests that conventional Large Eddy Simulations and Earth System Models that neglect these fluctuations underestimate cloud droplet formation.

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Jesse C. Anderson, Payton Beeler, Mikhail Ovchinnikov, Will Cantrell, Steven Krueger, Raymond A. Shaw, Fan Yang, Laura Fierce. 2022-10-27. Enhancements in cloud condensation nuclei concentrations from turbulent fluctuations in supersaturation. https://arxiv.org/abs/2210.15766

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