Dust Weather Research Articles

Increasing cross-border dust storm from Mongolia to China during 1987–2022

Mongolia and northern China have the highest frequency of dust weather in Northeast Asia. Dust transport from Mongolia to China is a major cause of dust weather in northern China. However, there has been limited research on the frequency changes of cross-border dust storms from Mongolia to China over the past few decades. Based on observational data, we analyzed the variation in cross-border dust storms between China and Mongolia during 1987–2022. The results indicate that, on average, approximately seven cross-border dust storm events occur annually between China and Mongolia, predominantly during the spring. The frequency of cross-border dust storms from Mongolia to China significantly increased from 2.2 events in P1 (1987–1999) to 7.5 events in P2 (2000−2022). Long-term trends suggest that rising dust emissions in east-central Mongolia largely contributed to this increase. The increase in cross-border dust storms from Mongolia to China in the spring was driven by more frequent cyclones in eastern Mongolia and Northeast China during P2. This is evidenced by a negative height anomaly and increased vorticity at 850 hPa over Northeast China. The cyclones were linked to the northward shift of the East Asian Polar Front Jet Stream (EAPJ) at 300 hPa between 50°N and 60°N. Additionally, surface conditions such as higher temperatures and decreased vegetation in Mongolia contributed to the increased frequency of cross-border dust storms from P1 to P2.

Establishing an Early Warning System for Dust Storms in Peri-Desert Regions

The Taklimakan Desert in northwest China stands as a significant contributor to dust storms, with its fringe oases already designated as ecologically fragile due to the severe impacts of these storms. This study focuses on Moyu County, situated on the southwest edge of the Taklimakan Desert, examining the origin and transport pathways of dust storms from 2004 to 2021. The classification involves utilizing a 36 h backward trajectory model and the k-means clustering technique, resulting in three clusters displaying distinct transport pathways and entry directions. Air pollutant concentrations at the study site corresponding to each cluster are analyzed to elucidate the contribution of dust storms from different directions. The results categorize 1952 dusty days into three categories: NE-SE (cluster 1), N-N (cluster 2), and NW-W (cluster 3). The highest frequency of dust storms, accounting for 64% of the total suspended dust weather, originates from the northeast and southeast direction (NE-SE category), with relatively weak intensity, mainly as suspended dust (71.5%). Strong sand storms predominantly occur from the northwest direction (57.8%). Cluster 1 (the southeast direction) exhibits a higher concentration of SO2, NO2, and CO, mainly associated with its pathway over anthropogenically polluted areas. Conversely, Cluster 3 (northwest direction) shows higher PM10 and PM2.5 concentrations due to increased wind speed and stronger dust storm intensity. The study develops dust storm early warning schemes based on 15-day advance predictions, utilizing an 18-year trajectory model and local monitoring data. This proposed warning scheme serves as a predictive tool for potential dust storm events and air pollution levels, aiding in both scientific research and policy formulation for dust storm mitigation and adaptation. The data obtained also hols relevance for conducting further scientific research in this field.

Assessing the impact of dust events on the Holiday Climate Index in the Taklimakan Desert region.

As a significant sector within the tourism industry, desert tourism has developed rapidly in recent years, contributing significantly to local economic development. On the other hand, desert tourism is constantly influenced by the desert climate, characterized by high temperatures, aridity, and dust events. This study examines and analyzes the impact of dust events on the Holiday Climate Index (HCI) using an improved methodology. It incorporates comprehensive meteorological data including temperature, relative humidity, cloud cover, precipitation, wind speed and dust events of Tazhong, located in the heart of the Taklimakan Desert. The results indicate that the maximum mean monthly HCI dips from an ideal level (91) to a very good level (73), the minimum dips from good level (66) to a marginal level (47), and the annual comfortable days (HCI ≥ 80) decrease from 180.5 to 95.3 after considering the impacts of dust events. The corrective HCI indicates that autumn, especially October, offers relatively comfortable climatic conditions for tourism, with the mean monthly comfortable days reach 20.1. These findings can better guide desert tourism activities and also demonstrate that the impact of dust weather on tourism activities cannot be ignored.

Precipitation of amorphous iron and aluminum during the weathering of rock dust in soil columns

Precipitation of amorphous iron and aluminum during the weathering of rock dust in soil columns

The Importance of Wind Simulations over Dried Lake Beds for Dust Emissions in the Middle East

Dust storms are one of the major environmental hazards affecting the Middle East countries, and largely originate in vast deserts and narrow dried lake beds. This study analyzes the inter-annual variation in dust weather conditions from 2000 to 2020 using data obtained from ten meteorological stations located around dried (completely or partly) lakes in Northwest (Urmia Lake) and South (Bakhtegan Lake) Iran. Since the wind regime is one of the most important factors controlling dust emissions in the dust source areas, wind speed simulations from the Weather Research and Forecasting (WRF) Model for 134,113 grid points covering the Middle East area, with a resolution of 5 km, were analyzed and compared with wind measurements at the stations around Urmia and Bakhtegan Lakes from 2005 to 2015. The analysis shows that the annual number of dust days was highly variable, presenting a significant increase at the stations around Urmia Lake during 2008–2011 and at the stations around Bakhtegan Lake in 2007–2012. Eleven years of WRF simulations of the mean diurnal wind patterns revealed that the highest 10 m wind speed occurred mostly around the local noon (12 to 15 UTC), generally coinciding with the majority of the reported dust codes within this time frame, as a result of the association between wind speed and dust emissions (dust weather conditions) around these lake basins. Consequently, accurate wind simulation has high importance for unbiased numerical prediction and forecasting of dust conditions. The comparison between the measured mean monthly 10 m wind speed and WRF-simulated 10 m wind speed revealed that the model overestimated wind data in all the stations around the Bakhtegan Lake but performed better at reconstructing the wind speeds at stations around Urmia Lake. Furthermore, notable differences were observed between measured and simulated wind directions, thus leading to uncertainties in the simulations of the dust-plume transport.

Characteristics of spring Mongolian cyclones in the recent 70 years: Background circulations and weather influences

AbstractBased on the fifth‐generation reanalysis (ERA5) data of the European Centre for Medium Range Weather Forecasts (ECMWF), spring Mongolian cyclones were examined from 1950 to 2023. Then, based on the feature parameters of activity path information, machine learning method (k‐means) is used to classify the trajectories of spring Mongolian cyclone. Subsequently, the atmospheric circulation configurations of the three categories of Mongolian cyclones and their influence on the weather in China verify the reasonability of the classification method. Specifically: (1) eastward moving type, affecting Inner Mongolia and Northeast China (Clus‐1). The circulation background of the Clus‐1 cyclone displays a broad negative geopotential height anomaly centre over East Asia; (2) northeastward moving type, affecting northeast part of Northeast China (Clus‐2). The circulation background of the Clus‐2 cyclones shows a “positive–negative–positive” distribution of circulation anomalies in the European Plain, Lake Baikal and the Sea of Japan; (3) southeastward moving type, this type can move to the south of China (Clus‐3). The circulation background of the Clus‐3 cyclones is opposite to that of the Clus‐2 cyclones. The three categories of Mongolian cyclones will cause dust weather and strong winds in different regions of China, mainly affecting Inner Mongolia and Northeast China.

Effect of Grassland Fires on Dust Storms in Dornod Aimag, Mongolia

Grassland fires and dust weather in Mongolia can trigger major cascading disasters. Grassland fires from autumn to the following spring can indirectly affect dust weather occurrence in the spring by affecting land surface vegetation cover. In this paper, we selected the aimag (province) of Dornod, Mongolia, a typical temperate grassland area, as the study area. The study aims to (1) analyze the spatiotemporal patterns of grassland fire and dust weather in the past 22 years, as well as the effect of grassland fire on dust weather and to (2) explore in depth the mechanisms of the effects of grassland fire on dust weather. To achieve these goals, we utilize high-resolution satellite burned-area data and Synop dust data. In general, grassland fire and dust weather occurrence clearly varied spatiotemporally across the study area. Grassland fires are typically more frequent in spring and autumn, and dust weather is mainly concentrated in spring. Cumulative grassland fires (both days and burned area) from autumn to the following spring affected the spring cumulative dust weather days significantly, especially the spring cumulative dust storm days. Analysis of the mechanism of the effect of grassland fire on dust storms showed that abundant summer precipitation resulted in higher vegetation cover and more accumulated fuel from autumn to April of the following spring. Consequently, the cumulative grassland fire days were higher, and the cumulative burned area was larger during the period, leading to a significant increase in cumulative dust storm days in May of the spring. In Mongolia, grassland fires are often caused by human factors. The findings of the present study could facilitate the crafting of measures to prevent and reduce grassland fires and indirectly minimize dust weather frequency to protect the ecological environment and promote sustainable development.

Analysis and Research on the Differences in Observed Data of Sand–Dust Weather between China and Mongolia

The difference in meteorological factors (such as weather phenomena, wind speed, and visibility) of sand–dust weather between China and Mongolia from 2011 to 2021 was analyzed using meteorological observational data and international exchange of meteorological observation data. Additionally, consistency analysis was performed by integrating satellite retrieval products with meteorological observation data. The results showed that the average annual frequency of sand–dust weather in Mongolia was significantly higher than that in China. In China, the sand–dust weather was mainly characterized by floating dust or blowing dust, while in Mongolia, it was primarily characterized by blowing dust or a sand and dust storm. The average annual wind speed and visibility during sand–dust weather in Mongolia were relatively higher than those in China. Based on the dust grade standard of China, when the floating dust occurred in Mongolia, there were cases with wind speed > level 3 and visibility > 10 km; when the blowing dust or sand and dust storm occurred in Mongolia, there were cases with wind speed ≤ level 3 and visibility > 10 km. In China, the sand–dust weather mainly occurred in the spring, while the sand-dust weather occurred frequently throughout the year in Mongolia. The number of days with dust lasting for 2 days or more in Mongolia exceeded that of China, and Mongolia had a significant impact on the sand–dust weather in China. According to the ground observation data and satellite retrieve products during the dust events, all dust events that significantly affected China and Mongolia during the same period from 2021 to 2022 were classified into three categories; among them, the proportion of types of large-scale sand–dust weather phenomena observed by both satellite and ground observation stations was significantly higher (6 times). By integrating ground observation data and satellite retrieval products and following the dust grade standard of China, the consistent correction of sand–dust weather phenomena was carried out. This laid the foundation for the future development of international dust grade standards and provided technological support for improved dust forecasting services in the Asian region.

A Study on Heavy Metal Sources and Pollution: Challenge to Biological and Ecosystem

The heavy metals pollution is a major environmental problem the modem world is facing today. These are major inorganic contaminants in the environment. Though a number of heavy metals are essential micronutrients for both plants and animals, but these are toxic at higher concentrations. The heavy metal ions of Al, Cr, Mn,Ca, Fe, Ni, Ca, Zn, Cd, Hg and Pb are major inorganic contaminants in the environment. These also affect soil microbial populations and their metabolic activities. These adversely affect the molecular mechanisms of life. The weathering of bedrock, volcanoes, forest fires and dust are natural sources of heavy metals to soils and ecosystems. The man made activities such as mining, smelting, printing, battery-manufacturing, electroplating, tanning etc. are resulting in high concentrations of these metals in the environments. This study described the different sources of heavy metals and their health hazards.

Study on the vibration control method of a turboshaft engine rotor based on piezoelectric squeeze film damper oil film clearance

Abstract. In the complex environment of the battlefield and dust weather, hard objects including birds, bullets, sand and others will inevitably cause impact damage to the compressor blades of turboshaft engines. The damage will further result in fatigue vibration of the gas generator rotor and catastrophic accidents such as excessive engine vibration and even crash. The relation between oil film clearance of dampers and damping of rotor systems as well as the damping and vibration amplitude of a rotor system are analyzed. The functional relation between oil film clearance and vibration amplitude is derived. Taking the gas generator rotor of a certain turboshaft engine as an example, the rotor dynamic model of a gas generator rotor with oil film bearing clearance is constructed, and the vibration response of the rotor system under different oil film clearances is analyzed. A new type of squeeze film damper (SFD) structure with piezoelectric-driven split pads is innovatively designed, and the vibration control system of the gas generator rotor is built. In addition, experimental research on rotor fault vibration control under different oil film clearances is carried out. The results show that, within a certain range, when oil film clearance decreases, amplitude will decrease. Under the experimental conditions, when the driving voltage of the piezoelectric actuator is adjusted from 0 to 70 V, the oil film clearance decreases from 156 to 118 µm. Then, the vibration amplitude decreases and gradually reaches stability after 0.036 s, and the vibration amplitude of the rotor system decreases by 12 %. When the driving voltage of the piezoelectric actuator is adjusted to 150 V, the oil film clearance decreases to 76 µm, and the vibration amplitude of the rotor system decreases by 28 %. When the new SFD adopts a piezoelectric-driven split-pad structure, the structure can adjust quickly the oil film clearance online so as to control the vibration of the rotor system. The research results can provide a technical reference for the vibration control of turboshaft engine rotor systems.

Characteristics of Dust Weather in the Tarim Basin from 1989 to 2021 and Its Impact on the Atmospheric Environment

Dust emission is a common catastrophic weather phenomenon in Northern China. This phenomenon not only causes environmental problems, such as air pollution, but also has an important impact on the global dust cycle and climate change. On the basis of the dust weather observation data of 44 surface meteorological stations in the Tarim Basin from 1989 to 2021, combined with the dust aerosol optical depth (DAOD), dust surface mass concentration (DUSMASS) and wind speed data, this paper analyses the spatial and temporal dust weather characteristics in the Tarim Basin over the past 33 years. Results show that the frequency of dust weather in the Tarim Basin has declined in the past 33 years. Dust weather mainly consisted of floating dust, followed by blowing dust and dust storm. This weather had a significant seasonal change, with more dust in spring and summer and less in autumn and winter. The dust weather was mainly distributed along the south edge of the Tarim Basin and the desert hinterland of Tazhong. The spatial distribution of the dust intensity (DI) index was basically consistent with the dust weather days. Moreover, the DAOD was obviously affected by dust weather and had a significant positive correlation with the number of dust weather days and the DI, suggesting the vertical concentration of dust particles to a certain extent. Wind is also one of the most important factors affecting the release of dust. The frequency of strong wind weather decreases from the northeast to the southwest, which corresponds to the distribution of the DUSMASS.

Unsupervised Image Dedusting via a Cycle-Consistent Generative Adversarial Network

In sand–dust weather, the quality of the image is seriously degraded, which affects the ability of advanced applications to image using remote sensing. To improve the image quality and enhance the performance of image dedusting, we propose an end-to-end cyclic generative adversarial network (D-CycleGAN) for image dedusting, which does not require pairs of sand–dust images and corresponding ground truth images for training. In other words, we train the network in an unpaired way. Specifically, we designed a jointly optimized guided module (JOGM), comprised of the sandy guided synthesis module (SGSM) and the clean guided synthesis module (CGSM), which aim to jointly guide the generator through corresponding discriminator adversarials to reduce the color distortion and artifacts. JOGM can significantly improve image quality. We propose a network hidden layer adversarial branch to perform adversarials from inside the network, which better supervises the hidden layer to further improve the quality of the generated images. In addition, we improved the original CycleGAN loss function and propose a dual-scale semantic perception loss in feature space and a color identity-preserving loss in pixel space to constrain the network. Extensive experiments demonstrate that our proposed network model effectively removes sand dust, has better clarity and image quality, and outperforms the state-of-the-art techniques. In addition, the proposed method can help the target detection algorithm to improve its detection accuracy and capability, and our method generalizes well to the enhancement of underwater images and hazy images.

Distribution, Transport, and Impact on Air Quality of Two Typical Dust Events in China in 2021

The dust event from 12 January to 17 January 2021 (“1.12 event”) is the first dust process in 2021 and the earliest dust event in the last two decades. The dust event from 14 to 18 March 2021 (“3.15 event”) was the strongest dust storm in the past decade. Distribution, transport, and impact on urban air quality of these two typical dust events were studied using multi-source satellite data, a HYSPLIT trajectory model, and a 3D concentration-weighted trajectory model. Results show that both dust events affected a wide range of areas, covering Northwest, North, Northeast, East, and Central-South China. A strong dust belt spanning Northwest, North, and Northeast China was formed in northern China on 15 March 2021. The distribution heights of the 1.12 and 3.15 events were 0–5 km and 0–10 km, respectively. Dust from western Inner Mongolia and southern Mongolia dominated the 1.12 event, while dust from southern Mongolia dominated the 3.15 event. Both of these dust sources had eastward and southeastward transport paths. The majority of the dust was near-ground in downstream cities from an altitude of 0–3 km. Most cities were affected by the dust backflow. The 1.12 event generated more severe particulate pollution in southern China than the 3.15 event. During high-value dust days, ozone pollution levels decreased at the majority of stations. Dust weather with low dust rising heights and dust backflow phenomena should be taken seriously in urban dust pollution forecasting and warning work. International collaboration is needed to improve China’s desertification control.

Classification and sources of extremely severe sandstorms mixed with haze pollution in Beijing

Air quality has significantly improved in China; however, new challenges emerge when dust weather is combined with haze pollution during spring in northern China. On March 15, 2021, an extremely severe sandstorm occurred in Beijing, with hourly maximum PM10 and PM2.5 concentrations reaching 5267.7 μg m−3 and 963.9 μg m−3, respectively. Continuous sandstorm events usually lead to complicated pollution status in spring. Three pollution types were identified disregarding the time sequence throughout March. The secondary formation type was dominant, with high ratios of PM2.5/PM10 (mean 74%) and PM1/PM2.5 (mean 52%). This suggests that secondary transformations are the primary cause of heavy pollution, even during the dry seasons. Sandstorm type resulted in dramatic PM10 levels, with a noticeable decrease in PM2.5/PM10 levels (27%), although PM2.5 levels remain high. The transitional pollution type was distinguished by an independent increase in PM10 levels, although PM2.5 and PM1 levels differed from the PM10 levels. Throughout March, the sulfur oxidation rate varied considerably, with high levels during most periods (mean 0.52). A strong correlation indicated that relative humidity was the primary variable promoting the formation of secondary sulfate. Sandstorms promote heterogeneous reactions by providing abundant reaction surfaces from mineral particles, therefore aggravating secondary pollution. The sandstorm air mass from the northwest passing through the sand sources of Mongolia carried not only crustal matter but also organic components, such as bioaerosols, resulting in a sharp increase in the organic carbon in PM2.5.

Spatio-temporal variation of PM2.5 pollution in Xinjiang and its causes: The growing importance in air pollution situation in China

Due to the differences in topographic features, water vapor distribution and emission structures between the north and south of Xinjiang Uygur Autonomous Region (hereinafter Xinjiang), the air pollution exhibits remarkable spatial heterogeneity in this region. In this study, Xinjiang is divided into four regions from north to south at the municipality scale based on the data from air quality monitoring sites recorded from 2013–2019, namely, the clean area in the north of northern Xinjiang (region I), the heavily polluted area of the Urumqi-Changji-Shihezi region (region Ⅲ), the moderately polluted area in the north of southern Xinjiang (region Ⅱ), and the severely polluted area in the south of southern Xinjiang (region Ⅳ). For highly polluted regions in northern and southern Xinjiang, regions Ⅲ and Ⅳ are compared with those typical polluted regions in central and eastern China, and the spatio-temporal variation characteristics and the causes of PM2.5 pollution in each sub-region are discussed. The results show that the region Ⅲ is a typical area with anthropogenic air pollution source, where the occurrence frequency of PM2.5 pollution with the intensity of moderate level or above (18%) is higher than the most heavily polluted area in central and eastern China (16%, regions from the south of North China to the west of Huang-Huai). The region IV is a typical area affected by dust weather, where the pollution frequency being about 52% is much higher than that in other typical polluted regions. In addition, under the combined effects of anthropogenic sources and dust aerosols, the pollution duration in region II is prolonged. Therefore, in contrast to the remarkable improvement of air quality in central and eastern China, the air pollution in typical regions of Xinjiang has become relatively more severe in recent years. Moreover, as Xinjiang is in the upstream of the central and eastern China in the mid-latitude westerlies, the heavy pollution due to sand and dust, anthropogenic sources and their mixing effects has a far-reaching impact on the downstream areas, further highlighting the growing importance of pollution prevention and control in Xinjiang.

Evaluation of a high-speed hybrid OAM-OFDM-MDM multiplexed coherent FSO system under desert conditions

To meet the needs of future wireless optical networks, this paper introduces a high-speed, hybrid multiplexed, coherent free-space optical (FSO) communication system that integrates an orbital angular momentum (OAM) multiplexed signal with an orthogonal frequency division multiplexing (OFDM) technique. Two independent QAM polarized beams, each carrying in-phase and quadrature (I/Q) phase 16-QAM-OFDM modulated data, are combined using mode division multiplexing (MDM) to increase the capacity of the proposed system. The reason of choosing OFDM is its capability to support higher data rate, and mitigating intersymbol interference (ISI). The signal is detected using a coherent detection-based digital signal processing (DSP) algorithm at the receiver end. The proposed hybrid FSO system is evaluated in low and heavy dust environments using bit error rate (BER), link distance, optical signal-to-noise ratio (OSNR), and received optical power performance matrices. The simulation results demonstrate the successful transmission of a 120 Gb/s single carrier over the longest link ranges of 1.5 and 0.40 km, respectively, under low and heavy dust weather environments below the signal degradation threshold value (forward error correction (FEC) limit) of BER 2.2 × 10–3 in strong turbulent conditions.

Summary of the impact of aeolian sand environment on key parts of wind turbine

<p indent="0mm">With the global implementation of the double carbon plan, the wind turbine industry has developed rapidly recently. The wind and sand environments significantly impact the operation of wind turbines. Wind farms are typically located in an area with large reserves of wind resources and can coexist harmoniously with the local environment. Although the desert area has substantial wind energy reserves, it is frequently affected by windy and dusty weather. First, this paper summarizes the distribution of deserts and the corresponding usage of wind energy globally; then, it briefly describes the core factors of the dusty weather, namely, sand source, dust movement form, and dust weather characteristics; finally, the research on the influence of wind and sand on the key components of wind turbines in the wind-sand environment is reviewed, and the research prospect is discussed. The purpose is to provide a reference for the technicians engaged in relevant research, hoping to support the collaborative improvement of wind energy usage and the desertification environment.

Dust radiation effect on the weather and dust transport over the Taklimakan Desert, China

The regional and longer-duration dust weather in the Taklimakan Desert (TD) is mostly caused by the east-pathway dust events, which bring large amounts of dust aerosol to impact the local weather and air quality, but the dust-induced radiation feedback on meteorological processes and the dust cycle in TD is still unclear. Both dust absorption and scattering of shortwave (SW) and longwave (LW) radiation are important for dust radiation feedback (DRF), while most numerical simulations neglect the dust LW scattering effect. In this paper, we modify WRF-Chem v3.8.1 (Weather Research and Forecasting model coupled with chemistry) to include the full dust radiation effect in an only-dust simulation. Three east-pathway TD dust events were simulated by this modified WRF-Chem. For each dust event, four sensitive experiments were conducted: with SW + LW DRF, with only SW DRF, with only LW DRF, and without DRF. The modified WRF-Chem can reproduce the dust evolution and reasonably simulate the DRF. DRF enhances the mean 2-m air temperature (T2m) field by ∼1 °C in the TD and lowers the daily T2m range in the southern TD by 1.9–4.3 °C. The positive feedback of mean T2m owns mostly to two equally important contributors, i.e., the dust LW radiation impact and the synergistic impact between dust SW and LW radiation quantified by the factor separation technique. For these dust events, DRF enhances both dust loading (10–20%) and dust deposition in most TD areas, but with different impacts on the dust emission in the hinter (increasing) and the southern edge (decreasing) of the TD area. With a dynamic lift caused by mountain forcing and the DRF, the dust plume could be lifted higher in the southern TD.

Characteristics and a mechanism of dust weather in Northern China

Characteristics and a mechanism of dust weather in Northern China

Dust image restoration based on channel difference prior and depth residual attention network

Images captured in dust weather have severe yellow and local red, and traditional color correction methods have low robustness. Thus, a dust image restoration method based on channel difference prior (CDP) and a depth residual attention network is proposed in this paper. First, CDP based on statistical observations is defined and used to acquire a dust image dataset. Then, a deep residual network that combines channel-spatial attention is introduced, and channel attention and spatial attention are used to describe important information for every residual block feature. Finally, channel fusion and nonlinear outputs are used to generate clear images. Rich experiments have confirmed the effectiveness and rationality of the proposed method.