Prediction of Asian Dust Days over Northern China Using the KMA-ADAM2 Model

Abstract This study evaluates the Korea Meteorological Administration (KMA) Asian Dust Aerosol Model 2 (ADAM2) for Asian dust events over the dust source regions in northern China during the first half of 2017. Using the observed hourly particulate matter (PM) concentration from the China Ministry of Environmental Protection (MEP) and station weather reports, we find that a threshold value of PM10–PM2.5 = 400 μg m−3 works well in defining an Asian dust event for both the MEP-observed and the ADAM2-simulated data. In northwestern China, ADAM2 underestimates the observed dust days mainly due to underestimation of dust emissions; ADAM2 overestimates the observed Asian dust days over Manchuria due to overestimation of dust emissions. Performance of ADAM2 in estimating Asian dust emissions varies quite systematically according to dominant soil types within each region. The current formulation works well for the Gobi and sand soil types, but substantially overestimates dust emissions for the loess-type soils. This suggests that the ADAM2 model errors are likely to originate from the soil-type-dependent dust emissions formulation and that the formulation for the mixed and loess-type soils needs to be recalibrated. In addition, inability to account for the concentration of fine PMs from anthropogenic sources results in large false-alarm rates over heavily industrialized regions. Direct calculation of PM2.5 in the upcoming ADAM3 model is expected to alleviate the problems related to anthropogenic PMs in identifying Asian dust events.

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Performance of KMA-ADAM3 in Identifying Asian Dust Days over Northern China

Atmosphere ◽

10.3390/atmos11060593 ◽

2020 ◽

Vol 11 (6) ◽

pp. 593

Author(s):

Sang-Boom Ryoo ◽

Jinwon Kim ◽

Jeong Hoon Cho

Keyword(s):

Dust Emission ◽

Northern China ◽

Asian Dust ◽

Probability Of Detection ◽

Soil Types ◽

Dust Source ◽

Aerosol Model ◽

Dust Generation ◽

Source Regions ◽

Dust Events

Recently, the Korea Meteorological Administration developed Asian Dust Aerosol Model version 3 (ADAM3) by incorporating additional parameters into ADAM2, including anthropogenic particulate matter (PM) emissions, modification of dust generation by considering real-time surface vegetation, and assimilations of surface PM observations and satellite-measured aerosol optical depth. This study evaluates the performance of ADAM3 in identifying Asian dust days over the dust source regions in Northern China and their variations according to regions and soil types by comparing its performance with ADAM2 (from January to June of 2017). In all regions the performance of ADAM3 was markedly improved, especially for Northwestern China, where the threat score (TS) and the probability of detection (POD) improved from 5.4% and 5.5% to 30.4% and 34.4%, respectively. ADAM3 outperforms ADAM2 for all soil types, especially for the sand-type soil for which TS and POD are improved from 39.2.0% and 50.7% to 48.9% and 68.2%, respectively. Despite these improvements in regions and surface soil types, Asian dust emission formulas in ADAM3 need improvement for the loess-type soils to modulate the overestimation of Asian dust events related to anthropogenic emissions in the Huabei Plain and Manchuria.

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Characterization of atmospheric bioaerosols along the transport pathway of Asian dust during the Dust-Bioaerosol 2016 Campaign

10.5194/acp-2017-1172 ◽

2017 ◽

Author(s):

Kai Tang ◽

Zhongwei Huang ◽

Jianping Huang ◽

Teruya Maki ◽

Shuang Zhang ◽

...

Keyword(s):

Climate Change ◽

Bacterial Communities ◽

Northern China ◽

Asian Dust ◽

Sequencing Analysis ◽

Dapi Staining ◽

Transport Pathway ◽

Dust Clouds ◽

Airborne Microbes ◽

Dust Events

Abstract. Previous studies have shown that bioaerosols are injected into the atmosphere during dust events. These bioaerosols may affect leeward ecosystems, human health and agricultural productivity and may even induce climate change. However, bioaerosol dynamics have rarely been investigated along the transport pathway of Asian dust, especially in China, where dust events affect huge areas and massive numbers of people. Given this situation, the Dust-Bioaerosol (DuBi) Campaign was carried out over northern China, and the effects of dust events on the amount and diversity of bioaerosols were investigated. The results indicate that the number of bacteria showed remarkable increases during the dust events, and the diversity of the bacterial communities also increased significantly, as determined by means of microscopic observations with 4,6-diamidino-2-phenylindole (DAPI) staining and MiSeq sequencing analysis. These results indicate that dust clouds can carry many bacteria of various types into downwind regions and may have potentially important impacts on ecological environments and climate change. The abundances of DAPI-stained bacteria in the dust samples were one to two orders of magnitude greater than those in the non-dust samples and reached 105 ~ 106 particles m−3. Moreover, the charge capacity of yellow fluorescent particles associated with the DAPI-stained bacteria increased from 5.1 % ± 6.3 % (non-dust samples) to 9.8 % ± 6.3 % (dust samples). A beta diversity analysis of the bacterial communities demonstrated the distinct clustering of separate prokaryotic communities in the dust and non-dust samples. Actinobacteria, Bacteroidetes, Proteobacteria remained the dominant phyla in all samples. As for Erenhot, the relative amounts of Acidobacteria and Chloroflexi have a remarkable rise in dust events. Alphaproteobacteria made the major contribution of the increasing relative amounts of the phylum proteobacteria in all dust samples. In the future, the viability and activity of airborne microbes, the interactions between bioaerosols and other gaseous and solid components in the air, and the effects of bioaerosols on animals and plants, ecological environments and the climate system must be studied in depth to help us understand the behavior of bioaerosols in the air and dust clouds in greater detail.

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Radiative feedbacks of dust in snow over eastern Asia in CAM4-BAM

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-12683-2018 ◽

2018 ◽

Vol 18 (17) ◽

pp. 12683-12698 ◽

Cited By ~ 6

Author(s):

Xiaoning Xie ◽

Xiaodong Liu ◽

Huizheng Che ◽

Xiaoxun Xie ◽

Xinzhou Li ◽

...

Keyword(s):

Snow Cover ◽

Radiative Forcing ◽

Source Region ◽

Asian Dust ◽

Significant Feature ◽

The Tibetan Plateau ◽

Eastern Asia ◽

Dust Emissions ◽

Snow Albedo ◽

Aerosol Model

Abstract. Dust in snow on the Tibetan Plateau (TP) could reduce the visible snow albedo by changing surface optical properties and removing the snow cover through increased snowmelt, which leads to a significant positive radiative forcing and remarkably alters the regional energy balance and the eastern Asian climate system. This study extends our previous investigation in dust–radiation interactions to investigate the dust-in-snow radiative forcing (SRF) and its feedbacks on the regional climate and the dust cycle over eastern Asia through the use of the Community Atmosphere Model version 4 with a Bulk Aerosol Model parameterizations of the dust size distribution (CAM4-BAM). Our results show that SRF increases the eastern Asian dust emissions significantly by 13.7 % in the spring, countering a 7.6 % decrease in the regional emissions by the dust direct radiative forcing (DRF). SRF also remarkably affects the whole dust cycle, including transport and deposition of dust aerosols over eastern Asia. The simulations indicate an increase in dust emissions of 5.1 %, due to the combined effect of DRF and SRF. Further analysis reveals that these results are mainly due to the regional climatic feedbacks induced by SRF over eastern Asia. By reducing the snow albedo over the TP, the dust in snow mainly warms the TP and influences its thermal effects by increasing the surface sensible and latent heat flux, which in turn increases the aridity and westerly winds over northwestern China and affects the regional dust cycle. Additionally, the dust in snow also accelerates the snow-melting process, reduces the snow cover and then expands the eastern Asian dust source region, which results in increasing the regional dust emissions. Hence, a significant feature of SRF on the TP is the creation of a positive feedback loop that affects the dust cycle over eastern Asia.

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Seasonal Asian Dust Forecasting Using GloSea5-ADAM

Atmosphere ◽

10.3390/atmos11050526 ◽

2020 ◽

Vol 11 (5) ◽

pp. 526

Author(s):

Sang-Boom Ryoo ◽

Yun-Kyu Lim ◽

Young-San Park

Keyword(s):

South Korea ◽

Dust Emission ◽

Northeast Asia ◽

Bare Soil ◽

Asian Dust ◽

Forecasting Model ◽

Aerosol Model ◽

Soil Fraction ◽

Temporary Solution ◽

Dust Events

The springtime dust events in Northeast Asia pose many economic, social, and health-related risks. Statistical models in the forecasting of seasonal dust events do not fully account for environmental variations in dust sources due to climate change. The Korea Meteorological Administration (KMA) recently developed the GloSea5-ADAM, a numerically based seasonal dust forecasting model, by incorporating the Asian Dust and Aerosol Model (ADAM)’s emission algorithm into Global Seasonal Forecasting Model version 5 (GloSea5). The performance of GloSea5 and GloSea5-ADAM in forecasting seasonal Asian dust events in source (China) and leeward (South Korea) regions was compared. The GloSea5-ADAM solved the limitations of GloSea5, which were mainly attributable to GloSea5′s low bare-soil fraction, and successfully simulated 2017 springtime dust emissions over Northeast Asia. The results show that GloSea5-ADAM’s 2017 and 2018 forecasts were consistent with surface PM10 mass concentrations observed in China and South Korea, while there was a large gap in 2019. This study shows that the geographical distribution and physical properties of soil in dust source regions are important. The GloSea5-ADAM model is only a temporary solution and is limited in its applicability to Northeast Asia; therefore, a globally applicable dust emission algorithm that considers a wide variety of soil properties must be developed.

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Mineralogy and geochemistry of Asian dust: dependence on migration path, fractionation, and reactions with polluted air

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-7411-2020 ◽

2020 ◽

Vol 20 (12) ◽

pp. 7411-7428

Author(s):

Gi Young Jeong

Keyword(s):

Northern China ◽

Asian Dust ◽

Chinese Loess Plateau ◽

Geochemical Data ◽

Gobi Desert ◽

Data Sets ◽

Migration Path ◽

Chinese Loess ◽

Dust Events ◽

A Minor

Abstract. Mineralogical and geochemical data are essential for estimating the effects of long-range transport of Asian dust on the atmosphere, biosphere, cryosphere, and pedosphere. However, consistent long-term data sets of dust samples are rare. This study analyzed 25 samples collected during 14 Asian dust events occurring between 2005 and 2018 on the Korean Peninsula and compared them to 34 soil samples (<20 µm) obtained from the Mongolian Gobi Desert, which is a major source of Asian dust. The mineralogical and geochemical characteristics of Asian dust were consistent with those of fine source soils in general. In dust, clay minerals were most abundant, followed by quartz, plagioclase, K-feldspar, calcite, and gypsum. The trace element contents were influenced by the mixing of dust with polluted air and the fractionation of rare earth elements. Time-series analyses of the geochemical data of dust, combined with satellite remote sensing images, showed a significant increase in the Ca content in the dust crossing the Chinese Loess Plateau and the sandy deserts of northern China. Calcareous sediments in the sandy deserts and pedogenic calcite-rich loess are probable sources of additional Ca. Dust-laden air migrating toward Korea mixes with polluted air over East Asia. Gypsum, a minor mineral in source soils, was formed by the reaction between calcite and pollutants. This study describes not only the representative properties of Asian dust but also their variation according to the migration path, fractionation, and atmospheric reactions.

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Spring 2018 Asian Dust Events: Sources, Transportation, and Potential Biogeochemical Implications

Atmosphere ◽

10.3390/atmos10050276 ◽

2019 ◽

Vol 10 (5) ◽

pp. 276 ◽

Cited By ~ 3

Author(s):

Joo-Eun Yoon ◽

Jae-Hyun Lim ◽

Jeong-Min Shim ◽

Jae-Il Kwon ◽

Il-Nam Kim

Keyword(s):

Pacific Ocean ◽

North Pacific ◽

Mineral Dust ◽

Model Simulation ◽

North Pacific Ocean ◽

Northern China ◽

Asian Dust ◽

The North ◽

Dust Events ◽

The North Pacific

The input of aeolian mineral dust to the oceans is regarded as the major source in supplying bioavailable iron for phytoplankton growth. Severe dust events swept over East Asia during the 26 March to the 4 April 2018, decreasing air quality to hazardous levels, with maximum PM10 mass concentrations above 3000 μg m−3 in northern China. Based on a comprehensive approach that combines multiple satellite measurements, ground observations, and model simulation, we revealed that two severe Asian dust events originating from the Taklimakan and Gobi deserts on 26 March and 1 April, were transported through northern China and the East/Japan Sea, to the North Pacific Ocean by westerly wind systems. Transportation pathways dominated by mineral dust aerosols were observed at altitudes of 2–7 km in the source regions, and then ascending to 3–10 km in the North Pacific Ocean, with relatively denser dust plumes within the second dust episode than there were during the first. Our results suggest that mineral dust emitted from the Taklimakan and Gobi deserts could increase ocean primary productivity in the North Pacific Ocean by up to ~50%, compared to average conditions. This emphasizes the potential importance of the deposition of Asian mineral dust over the North Pacific Ocean for enhancing the biological pump.

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Inverting the East Asian Dust Emission Fluxes Using the Ensemble Kalman Smoother and Himawari-8 AODs: A Case Study with WRF-Chem v3.5.1

Atmosphere ◽

10.3390/atmos10090543 ◽

2019 ◽

Vol 10 (9) ◽

pp. 543

Author(s):

Dai ◽

Cheng ◽

Goto ◽

Schutgens ◽

Kikuchi ◽

...

Keyword(s):

Dust Emission ◽

Asian Dust ◽

Geostationary Satellite ◽

Satellite Observations ◽

Dust Emissions ◽

Total Dust ◽

Kalman Smoother ◽

Independent Observations ◽

Moderate Resolution Imaging Spectroradiometer ◽

Horizontal And Vertical Distributions

We present the inversions (back-calculations or optimizations) of dust emissions for a severe winter dust event over East Asia in November 2016. The inversion system based on a fixed-lag ensemble Kalman smoother is newly implemented in the Weather Research and Forecasting model and is coupled with Chemistry (WRF-Chem). The assimilated observations are the hourly aerosol optical depths (AODs) from the next-generation geostationary satellite Himawari-8. The posterior total dust emissions (2.59 Tg) for this event are 3.8 times higher than the priori total dust emissions (0.68 Tg) during 25–27 November 2016. The net result is that the simulated aerosol horizontal and vertical distributions are both in better agreement with the assimilated Himawari-8 observations and independent observations from the ground-based AErosol RObotic NETwork (AERONET), the satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS) and the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). The developed emission inversion approach, combined with the geostationary satellite observations, can be very helpful for properly estimating the Asian dust emissions.

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