Impact of Mineral Dust on Summertime Precipitation Over the Taiwan Region

Abstract. This paper presents the reconstruction of a 73-year time series of the aerosol optical depth (AOD) at 500 nm at the subtropical high-mountain Izaña Atmospheric Observatory (IZO) located in Tenerife (Canary Islands, Spain). For this purpose, we have combined AOD estimates from artificial neural networks (ANNs) from 1941 to 2001 and AOD measurements directly obtained with a Precision Filter Radiometer (PFR) between 2003 and 2013. The analysis is limited to summer months (July–August–September), when the largest aerosol load is observed at IZO (Saharan mineral dust particles). The ANN AOD time series has been comprehensively validated against coincident AOD measurements performed with a solar spectrometer Mark-I (1984–2009) and AERONET (AErosol RObotic NETwork) CIMEL photometers (2004–2009) at IZO, obtaining a rather good agreement on a daily basis: Pearson coefficient, R, of 0.97 between AERONET and ANN AOD, and 0.93 between Mark-I and ANN AOD estimates. In addition, we have analysed the long-term consistency between ANN AOD time series and long-term meteorological records identifying Saharan mineral dust events at IZO (synoptical observations and local wind records). Both analyses provide consistent results, with correlations >  85 %. Therefore, we can conclude that the reconstructed AOD time series captures well the AOD variations and dust-laden Saharan air mass outbreaks on short-term and long-term timescales and, thus, it is suitable to be used in climate analysis.

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The Impact of Ambient Atmospheric Mineral-Dust Particles on the Calcification of Lungs

Minerals ◽

10.3390/min11020125 ◽

2021 ◽

Vol 11 (2) ◽

pp. 125

Author(s):

Mariola Jabłońska ◽

Janusz Janeczek ◽

Beata Smieja-Król

Keyword(s):

Mineral Dust ◽

Smoking Habit ◽

Lower Lobe ◽

Ambient Air ◽

Dust Particles ◽

Masking Effect ◽

Amorphous Calcium Carbonate ◽

Calcium Salts ◽

The Impact ◽

First Time

For the first time, it is shown that inhaled ambient air-dust particles settled in the human lower respiratory tract induce lung calcification. Chemical and mineral compositions of pulmonary calcium precipitates in the lung right lower-lobe (RLL) tissues of 12 individuals who lived in the Upper Silesia conurbation in Poland and who had died from causes not related to a lung disorder were determined by transmission and scanning electron microscopy. Whereas calcium salts in lungs are usually reported as phosphates, calcium salts precipitated in the studied RLL tissue were almost exclusively carbonates, specifically Mg-calcite and calcite. These constituted 37% of the 1652 mineral particles examined. Mg-calcite predominated in the submicrometer size range, with a MgCO3 content up to 50 mol %. Magnesium plays a significant role in lung mineralization, a fact so far overlooked. The calcium phosphate (hydroxyapatite) content in the studied RLL tissue was negligible. The predominance of carbonates is explained by the increased CO2 fugacity in the RLL. Carbonates enveloped inhaled mineral-dust particles, including uranium-bearing oxides, quartz, aluminosilicates, and metal sulfides. Three possible pathways for the carbonates precipitation on the dust particles are postulated: (1) precipitation of amorphous calcium carbonate (ACC), followed by its transformation to calcite; (2) precipitation of Mg-ACC, followed by its transformation to Mg-calcite; (3) precipitation of Mg-free ACC, causing a localized relative enrichment in Mg ions and subsequent heterogeneous nucleation and crystal growth of Mg-calcite. The actual number of inhaled dust particles may be significantly greater than was observed because of the masking effect of the carbonate coatings. There is no simple correlation between smoking habit and lung calcification.

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INTERANNUAL VARIABILITY OF MINERAL DUST SIMULATED WITH A GENERAL CIRCULATION MODEL

Journal of Aerosol Science ◽

10.1016/s0021-8502(21)00060-4 ◽

2001 ◽

Vol 32 ◽

pp. 125-126

Author(s):

C. TIMMRECK ◽

M. SCHULZ ◽

Y. BALKANSKI ◽

J. FEICHTER

Keyword(s):

Interannual Variability ◽

General Circulation Model ◽

General Circulation ◽

Mineral Dust ◽

Circulation Model

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Cloud icing by mineral dust and impacts to aviation safety

Scientific Reports ◽

10.1038/s41598-021-85566-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Slobodan Nickovic ◽

Bojan Cvetkovic ◽

Slavko Petković ◽

Vassilis Amiridis ◽

Goran Pejanović ◽

...

Keyword(s):

Mineral Dust ◽

Weather Conditions ◽

Ice Nucleation ◽

Aircraft Accidents ◽

Ice Nuclei ◽

Loss And Damage ◽

Cloud Ice ◽

Convective Weather ◽

First Time ◽

Engine Power

AbstractIce particles in high-altitude cold clouds can obstruct aircraft functioning. Over the last 20 years, there have been more than 150 recorded cases with engine power-loss and damage caused by tiny cloud ice crystals, which are difficult to detect with aircraft radars. Herein, we examine two aircraft accidents for which icing linked to convective weather conditions has been officially reported as the most likely reason for catastrophic consequences. We analyze whether desert mineral dust, known to be very efficient ice nuclei and present along both aircraft routes, could further augment the icing process. Using numerical simulations performed by a coupled atmosphere-dust model with an included parameterization for ice nucleation triggered by dust aerosols, we show that the predicted ice particle number sharply increases at approximate locations and times of accidents where desert dust was brought by convective circulation to the upper troposphere. We propose a new icing parameter which, unlike existing icing indices, for the first time includes in its calculation the predicted dust concentration. This study opens up the opportunity to use integrated atmospheric-dust forecasts as warnings for ice formation enhanced by mineral dust presence.

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