Airborne Asian Dust: Case Study of Long-Range Transport and Implications for the Detection of Volcanic Ash

Abstract. As a part of the IGAC (International Global Atmospheric Chemistry) Mega-cities program, aerosol physical and optical properties were continuously measured from March 2007 to March 2008 at an urban site (37.57° N, 126.94° E) in Seoul, Korea. Spectral optical properties of long-range transported Asian dust and pollution aerosols have been investigated based on the year long measurement data. Optically measured black carbon/thermally measured elemental carbon (BC/EC) ratio showed clear monthly variation with high values in summer and low values in winter mainly due to the enhancement of light attenuation by the internal mixing of EC. Novel approach has been suggested to retrieve the spectral light absorption coefficient (babs) from Aethalometer raw data by using BC/EC ratio. Mass absorption efficiency, σabs (=babs/EC) at 550 nm was determined to be 9.0±1.3, 8.9±1.5, 9.5±2.0, and 10.3±1.7 m2 g−1 in spring, summer, fall, and winter, respectively with an annual mean of 9.4±1.8 m2 g−1. Threshold values to classify severe haze events were suggested in this study. Increasing trend of aerosol single scattering albedo (SSA) with wavelength was observed during Asian dust events while little spectral dependence of SSA was observed during long-range transport pollution (LTP) events. Satellite aerosol optical thickness (AOT) and Hysplit air mass backward trajectory analyses as well as chemical analysis were performed to characterize the dependence of spectral optical properties on aerosol type. Results from this study can provide useful information for studies on regional air quality and aerosol's effects on climate change.

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Long-range transport of polycyclic aromatic hydrocarbons (PAHs) from the eastern Asian continent to Kanazawa, Japan with Asian dust

Atmospheric Environment ◽

10.1016/j.atmosenv.2006.11.021 ◽

2007 ◽

Vol 41 (12) ◽

pp. 2580-2593 ◽

Cited By ~ 59

Author(s):

Shuji Tamamura ◽

Tsutomu Sato ◽

Yukie Ota ◽

Xilong Wang ◽

Ning Tang ◽

...

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Long Range ◽

Aromatic Hydrocarbons ◽

Asian Dust ◽

Long Range Transport ◽

Asian Continent ◽

Range Transport ◽

Polycyclic Aromatic

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Asian Long-Range Transport in Relation to Atmospheric Rivers in Northern California

Atmosphere ◽

10.3390/atmos10060313 ◽

2019 ◽

Vol 10 (6) ◽

pp. 313

Author(s):

Catherine N. Liu ◽

Sen Chiao ◽

Ju-Mee Ryoo

Keyword(s):

Long Range ◽

Cold Season ◽

Asian Dust ◽

Long Range Transport ◽

Back Trajectory ◽

Northern California ◽

Atmospheric Rivers ◽

Back Trajectory Analysis ◽

Range Transport ◽

Moderate Resolution Imaging Spectroradiometer

The study investigates the effect of aerosol long-range transport on precipitation over Northern California during atmospheric river (AR) events in the 2017 cold season (January–April). ARs in 2017 were one of the strongest to date, and the intense precipitation associated with the ARs resulted in flooding, destruction of property, and contamination of water supplies. The Aerosol Optical Depth (AOD) from Moderate Resolution Imaging Spectroradiometer (MODIS) data shows Asian dust traveling across the Northern Pacific Ocean along with AR events. Aerosol measurements in California, provided by the Interagency Monitoring of Protected Visual Environments (IMPROVE), show that more Asian dust tends to be observed over the coast, while non-Asian/localized dust is observed inland. A mixture of Asian and localized dust is observed over the mountains, although higher amounts of both are observed in the spring (March–April). Back trajectory analysis confirms that Asian aerosols are transported along the air parcels, and each AR event has its own transport pattern in terms of horizontal advection and vertical lifting. Correlation between precipitation and aerosols is low. This suggests that aerosols contribute little to the decrease of local precipitation during the 2017 AR events.

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Numerical simulations of windblown dust over complex terrain: The Fiambalá Basin episode in June 2015

10.5194/acp-2016-851 ◽

2016 ◽

Author(s):

Leonardo A. Mingari ◽

Estela A. Collini ◽

Arnau Folch ◽

Walter Báez ◽

Emilce Bustos ◽

...

Keyword(s):

Numerical Simulations ◽

Long Range ◽

Complex Terrain ◽

Volcanic Ash ◽

Dust Cloud ◽

Temporal Distribution ◽

Dust Particles ◽

Long Range Transport ◽

Mountain Range ◽

Range Transport

Abstract. On the 13 June 2015, the London Volcanic Ash Advisory Centre (VAAC) warned the Buenos Aires VAAC about a possible volcanic eruption from the Nevados Ojos del Salado volcano (6879 m), located in the Andes mountain range on the border between Chile and Argentina. A volcanic ash cloud was detected by the SEVIRI instrument on board the Meteosat Second Generation (MSG) satellites from 14:00 UTC on 13 June. Further studies concluded that the phenomenon was caused by remobilization of ancient pyroclastic deposits (circa 4.5 Ka Cerro Blanco eruption) from the Bolsón de Fiambalá (Fiambalá Basin) in northwestern Argentina. In this paper, we provide the first comprehensive description of the dust episode through observations and numerical simulations. We have investigated the spatio-temporal distribution of aerosols and the emission process over complex terrain to gain insight into the key role played by the orography and the condition that triggered the long-range transport episode. Numerical simulations of windblown dust were performed using the WRF-ARW/FALL3D modeling system with meteorological fields downscaled to a spatial resolution of 2 km in order to resolve the complex orography of the area. Results indicated that favourable conditions to generate dust uplifting occurred in northern Fiambalá Basin, where orographic effects caused strong surface winds. According to short-range numerical simulations, dust particles were confined to near-ground layers around the emission areas. On the other hand, dust aerosols were injected up to 5–6 km high in central and southern regions of the Fiambalá Basin, where intense ascending airflows are driven by horizontal convergence. Long-range transport numerical simulations were also performed to model dust cloud spreading over northern Argentina. Results of simulated vertical particle column mass were compared with the MSG-SEVIRI retrieval product. We tested two numerical schemes: with the default configuration of the FALL3D model, we found difficulties to simulate transport through orographic barriers, whereas an alternative configuration, using a numerical scheme to more accurately compute the horizontal advection in abrupt terrains, substantially improved the model performance.

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