Publication Date:
2015-04-01
Description:
Polar stratospheric clouds (PSCs) are critical elements of Arctic and Antarctic ozone depletion. We establish a PSC microphysics model using coupled chemistry, climate and microphysics models driven by specific dynamics. We explore the microphysical formation and evolution of STS (Super-cooled Ternary Solution) and NAT (Nitric-Acid Trihydrate). Characteristics of STS particles dominated by thermodynamics compare well with observations. For example, the mass of STS is close to the thermodynamic equilibrium assumption when the particle surface area is larger than 4 µm 2 /cm 3 . We derive a new nucleation rate equation for NAT based on observed denitrification in the 2010-2011 Arctic winter. The homogeneous nucleation scheme leads to supermicron NAT particles as observed. We also find that as the number density of NAT particles increases, the denitrification also increases. Simulations of the PSC lidar backscatter, denitrification and gas phase species are generally within error bars of the observations. However, the simulations are very sensitive to temperature, which limits our ability to fully constrain some parameters (e.g. denitrification, ozone amount) based on observations. This article is protected by copyright. All rights reserved.
Electronic ISSN:
1942-2466
Topics:
Geography
,
Geosciences
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