Impacts of Aerosol Loading on Surface Precipitation from Deep Convective Systems over North Central Mongolia

• Published in: Asia-Pacific journal of atmospheric sciences Vol. 54; no. 4; pp. 587 - 598
• Main Authors: Lkhamjav, Jambajamts, Lee, Hyunho, Jeon, Ye-Lim, Seo, Jaemyeong Mango, Baik, Jong-Jin
• Format: Journal Article
• Language: English
• Published: Seoul Korean Meteorological Society 01.11.2018; Springer Nature B.V; 한국기상학회
• Subjects: Aerosol effects; Aerosols; Atmospheric Sciences; Climatology; Coalescence; Condensation; Convective systems; Crystals; Earth and Environmental Science; Earth Sciences; Geophysics/Geodesy; High altitude; Ice; Ice crystals; Mass; Microphysics; Original Article; Precipitation; Snow; 대기과학; Mongolia; Aerosol loading impacts on surface precipitation; WRF model; Mongolia; Deep convective systems; Bin microphysics scheme
• ISSN: 1976-7633; 1976-7951
• DOI: 10.1007/s13143-018-0080-5

The impacts of aerosol loading on surface precipitation from mid-latitude deep convective systems are examined using a bin microphysics model. For this, a precipitation case over north central Mongolia, which is a high-altitude inland region, on 21 August 2014 is simulated with aerosol number concentrations of 150, 300, 600, 1200, 2400, and 4800 cm −3 . The surface precipitation amount slightly decreases with increasing aerosol number concentration in the range of 150–600 cm −3 , while it notably increases in the range of 600–4800 cm −3 (22% increase with eightfold aerosol loading). We attempt to explain why the surface precipitation amount increases with increasing aerosol number concentration in the range of 600–4800 cm −3 . A higher aerosol number concentration results in more drops of small sizes. More drops of small sizes grow through condensation while being transported upward and some of them freeze, thus increasing the mass content of ice crystals. The increased ice crystal mass content leads to an increase in the mass content of small-sized snow particles largely through deposition, and the increased mass content of small-sized snow particles leads to an increase in the mass content of large-sized snow particles largely through riming. In addition, more drops of small sizes increase the mass content of supercooled drops, which also leads to an increase in the mass content of large-sized snow particles through riming. The increased mass content of large-sized snow particles resulting from these pathways contributes to a larger surface precipitation amount through melting and collision-coalescence.