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Impact of Mineral Dust on Summertime Precipitation Over the Taiwan Region
Author(s) -
Zhang Yanda,
Yu Fangqun,
Luo Gan,
Chen JenPing,
Chou Charles C.K.
Publication year - 2020
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
eISSN - 2169-8996
pISSN - 2169-897X
DOI - 10.1029/2020jd033120
Subject(s) - precipitation , ice nucleus , environmental science , atmospheric sciences , water vapor , mineral dust , typhoon , climatology , aerosol , meteorology , geology , chemistry , geography , organic chemistry , nucleation
Dust particles are effective ice nuclei and are known to affect precipitation. Here, the possible impacts of mineral dust on summertime cloud and precipitation over the Taiwan region are investigated through analysis of 25 years (1989–2013) of multiple observational and modeling data sets. Due to the unique mechanism, typhoon precipitations are excluded from this study. Statistical methods (partial correlation and stratification) are used to untangle the influences of dust from the covarying meteorological conditions (water vapor, horizontal wind, sea surface temperature, and moisture flux). The results suggest a statistically significant positive correlation between nontyphoon precipitation and the number concentration of dust particles larger than 0.5 μm ( N d ) in July and August in the regions with heavy precipitation. From clean ( N d = ~ 0.008 cm −3 ) to dusty days ( N d = ~ 0.2 cm −3 ), averaged ice (liquid) water paths and precipitation increase by ~25% (~20%) and ~70% over the orographic region, and vertically, ~30% more cloud ice content is generated at ~350 hPa ( T = ~ −20°C), enhancing the development of the mixed‐phase cloud and precipitation. The results also indicate the critical role of the atmospheric water vapor in the responses of precipitation to N d , with precipitation increasing more significantly with N d in higher water vapor circumstances.