Dust Storm Days Research Articles

Dust storms and cardiorespiratory emergency department visits in three Southwestern United States: application of a monitoring-based exposure metric

Climate change is projected to increase the risk of dust storms, particularly in subtropical dryland, including the southwestern US. Research on dust storm’s health impacts in the US is limited and hindered by challenges in dust storm identification. This study assesses the potential link between dust storms and cardiorespiratory emergency department (ED) visits in the southwestern US. We acquired data for 2005–2016 from eight IMPROVE (Interagency Monitoring of PROtected Visual Environments) sites in Arizona, California, and Utah. We applied a validated algorithm to identify dust storm days at each site. We acquired patient-level ED visit data from state agencies and ascertained visits for respiratory, cardiovascular, and cause-specific subgroups among patients residing in ZIP codes within 50 km of an IMPROVE site. Using a case-crossover design, we estimated short-term associations of ED visits and dust storms, controlling for temporally varying covariates. During 2005–2016, 40 dust storm days occurred at the eight IMPROVE sites. Mean PM10 and PM2.5 levels were three to six times greater on dust storm days compared to non-dust storm days. Over the study period, there were 2 524 259 respiratory and 2 805 925 cardiovascular ED visits. At lags of 1, 2, and 3 days after a dust storm, we observed 3.7% (95% CI: 1.0%, 7.6%), 4.9% (95% CI: 1.1%, 8.9%), and 5.0% (95% CI: 1.3%, 8.9%) elevated odds of respiratory ED visits compared to non-dust storm days. Estimated associations of dust storm days and cardiovascular disease ED visits were largely consistent with the null. Using a monitoring-based exposure metric, we observed associations among dust storms and respiratory ED visits. The results add to growing evidence of the health threat posed by dust storms. The dust storm metric was limited by lack of daily data; future research should consider information from satellite and numerical models to enhance dust storm characterization.

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.

Investigation of the characteristics of atmospheric and meteorological parameters of a severe dust storm in the Mumbai during January 2022

In recent years, India has experienced frequent dust storms, which have a significant impact on local climatic conditions. This research focuses on a significant dust storm event that took place in January 2022 across the Arabian Sea and its effects on the Mumbai region. The study utilizes a combination of ground-based measurements and satellite observations of optical parameters to investigate different atmospheric and meteorological parameters. The analysis of aerosol optical characteristics observed through Moderate Resolution Imaging Spectroradiometer (MODIS) and Ozone Monitoring Instrument (OMI) data indicates significant variations during the dust storm day in comparison to pre- and post-dust storm days. There is a huge surge in the Aerosol Optical Depth (AOD) values Ångström Exponent (AE) values decrease. This confirms the presence of coarser particles in the affected region. The elevated values of the Aerosol Index (AI) on dusty days shows the presence of UV-absorbing aerosols. The ground-based measurements obtained by Central Pollution Control Board (CPCB) in the Mumbai region shows a rapid surge in the PM concentrations during the dust storm day. This study also highlights the change in the meteorological conditions associated with the occurrence of dust storm. The back trajectory analysis shows that most of the air-mass parcels transported from the Arabian Sea. The findings of this study collectively emphasize the substantial impact of dust storms on local atmospheric chemistry and the climatic system.

Aerosol-CCN characteristics and dynamics associated with a pre-monsoon dust storm over a high-altitude site in Western Ghats, India.

Aerosol-CCN characteristics and dynamics during a pre-monsoon dust storm (April 6-11, 2015) over a high-altitude site ((17.92°N, 73.66°E, and 1348m above mean sea level (MSL)) in Western Ghats, India, has been studied using ground-based observations, satellite, and reanalysis datasets. Spatial distribution of dust surface mass concentration along with the back trajectory analysis showed the Arabian Desert area (Rub-Al-khali desert) as the source region and strong westerly winds transported the dust particles toward the Indian subcontinent. High values noticed in the surface PM10 (PM2.5), i.e., ~ 450 (~ 130) µg m-3, MODIS AOD550nm (0.6), and MERRA 2 dust surface mass concentration (5 × 10-7kgm-3) along MODIS true color images confirmed the dust storm event on April 6, 2015 over the observational site. Size-segregated aerosol number concentration measured from ground-based observations showed the dominance of Aitken, accumulation, and coarse mode particles during dust period. CCN concentrations at 0.1, 0.3, 0.5, 0.7, and 0.9% SS were analyzed. A low value of CCN concentration and activation fraction (~ 0.3) near surface was noticed during dust storm day, suggesting insoluble mineral dust particle being transported. Analyzed vertical velocity during pre-dust period showed downdraft between 900 and 750hPa, suggesting dust transport from upper altitudes toward the observational site. WRF-Chem model simulation also captured the dust storm event, and the results are in good agreement with the observation with a significance of 95% confidence level.

Dust Outbreaks across East Iran: Application of Multi-Source Remote Sensing Data (AMSR-E and FengYun3-MWRI) on the Effects of Soil Moisture

One of the most significant hydro-meteorological and agricultural variables is soil moisture, yet measuring it remains a difficult task. Due to the significant spatial fluctuation of soil moisture, it is difficult to quantify it in a particular spot or field across a sizable region. Despite the thermal band's limitations in assessing soil moisture, MODIS and AVHRR, which are inappropriate were utilized in this investigation. The study examined the impact of soil moisture on dust outbreak. Soil moisture in the study domain was monitored using field techniques and the hybrid model. It combined multi-sourced remote sensing data, obtained from AMSER-E and FY-3 satellites. AMSER-E satellite measures the light temperature in five frequencies ranging from 6. 9 to 89 GHz based on data obtained from AMSER-E. Findings revealed areas with a spatial scale of 25 km2 has a 12-hour time step or variability in dust storm, thereby influencing soil moisture content within the zone of study. In addition to introducing acceptable potentials of the passive microwave band for accurate and applied monitoring of the soil moisture, the present results are viewed as a reliable source for studies on drought in time scale. The study shows that Zabol in Sistan has the highest annual average of 80.7 dust storm days. Soil moisture estimates serve a great deal for preparing soil moisture maps and the evaluation of temporal and spatial variations of soil moisture in study region to address issues related to dust storms.
 In order to identify the areas affected by dust storms and understand how dust particles are dispersed in the Sistan region, satellite image processing was employed using MODIS 1 sensor images obtained from the TERRA satellite.

Dust-storm frequencies, community attitudes, government policy and land management practices during three major droughts in New South Wales, Australia

This study assessed whether dust-storm frequency during major droughts in New South Wales (NSW), Australia, has changed and what may have caused any change. The frequency of days with dust storms, i.e. when visibility is <1000 m, is presented for the dust storm year (July to June), with the maximum number of dust storms for three major droughts, namely, 2017/20, Millennial and World War II droughts. Community attitudes, government policy and land management practices have changed since the 1940s, and these factors were reviewed to determine whether they explain changes in dust-storm frequency. Two data sources were used: meteorological weather codes from the Australian Bureau of Meteorology and dust particulate matter <10 µm (PM10) from the DustWatch/Rural Air Quality Monitoring Network. The particulate-matter data were converted to dust-storm days (DSD) to create a yearly time series. The meteorological data records were coded as dust storms and required no modification. Results showed that 1944/45 was the dustiest year, with 4.4 times more DSD than in 2019/20 and 9.9 times more DSD than in 2009/10. One reason for the higher DSD in 2019/20 than in 2009/10 was the area protected from wind erosion by vegetation cover above 50%. In 2019/20, 69% of NSW was protected from wind erosion, compared with 79% in 2009/10. We suggest the primary reasons for lower DSD in 2019/20 and 2009/10 than in 1944/45 were community attitudes, government policy and land management practices; these, in combination, help maintain vegetation cover. Since the 1940s, the focus of land management has changed from ‘taming the land’ to ‘sustainably using the land’. Government policy in the 2000s is focused on supporting farming businesses and communities to manage and prepare so as to successfully manage drought. Land management practices that maintain ground cover are now widely practised.

Water-soluble ions and source apportionment of PM2.5 depending on synoptic weather patterns in an urban environment in spring dust season

Emission sources and meteorological conditions are key factors affecting the intensity and duration of air pollution events. In the current study, using the daily concentrations of PM2.5 (particulate matter with a diameter ≤ 2.5 μm) and the water-soluble ions thereof in Lanzhou from March 1, 2021, to May 31, 2021, we investigated the contributions of emission sources and locations of potential sources through positive matrix factorization and potential source contribution function analysis. In addition, synoptic weather patterns affecting pollution were typed using T-model principal component analysis. The results revealed that the average concentrations of PM2.5 for the entire spring, dust storm days, and normal days were 54.3, 158.1 and 33.0 μg/m3, respectively. During dust storm days, sulfate produced from primary emissions was mainly present in the form of K2SO4, Na2SO4, MgSO4, and CaSO4, and nitrate was mainly produced through secondary conversion and took the form of NH4NO3. Dust, industrial entities, biomass combustion, metal smelting, secondary aerosol, and sea salt contributed to 32.0, 29.8, 13.4, 11.2, 10.8 and 2.7% of the spring PM2.5, respectively, in Lanzhou. The main potential sources of PM2.5 during the normal days were in the western parts of Lanzhou. Dust storms entered Lanzhou through the Hexi Corridor from several dust sources: southeastern Kazakhstan, Mongolia, the Kurbantungut Desert, and the Badain Jaran Desert. The northwest high-pressure; northern strong high-pressure and southwest low-pressure; northwest high-pressure and southwest high-pressure synoptic weather circulation types were prone to dust storms. Our results may provide a basis for local environmental governance.

Dust Storms and Respiratory Emergency Department Visits in the Southwestern United States

BACKGROUND AND AIM: Climate change is projected to increase the risk of dust storms, particularly in the southwestern US. Research on dust storm impacts is hindered by challenges in dust storm identification. This study assesses the potential link between dust storms and respiratory-related emergency department (ED) visits in the southwestern US. METHODS: We acquired data for 2005-2016 from IMPROVE (Interagency Monitoring of PROtected Environments) monitoring sites in California (n=2), Arizona (n=5), Nevada (n=2), and Utah (n=1). Applying a validated algorithm that identifies dust events of natural origin, dust storm days at each IMPROVE site were identified. We acquired patient-level ED visit data from state agencies and selected visits for respiratory diseases, asthma, and chronic obstructive pulmonary disease (COPD) among patients residing within 50 km of a monitoring site. Using a case-crossover design, we estimated associations of ED visits and dust storms, controlling for meteorology, ozone, and holidays. RESULTS: During 2005-2016, 37 dust storm days occurred at the 10 IMPROVE sites. Mean PM10 and PM2.5 levels were 3-6 times greater on dust compared to non-dust storm days. We observed associations of respiratory ED visits and dust storms, with strongest associations at lag 3 [odds ratio of 1.049 (95% confidence interval: 1.002-1.098)]. Results were driven by Arizona, with an odds ratio for respiratory ED visits of 1.068 (95% confidence interval: 1.008-1.133). Associations for asthma were similar, although with larger uncertainty given fewer ED visits. Associations for COPD were consistent with the null. CONCLUSIONS: Using a monitoring-based exposure metric, we observed associations among respiratory ED visits and dust storms. The results add to growing evidence of the health threat posed by dust storms. The dust storm metric was limited by lack of daily monitoring data; future research will incorporate satellite and models for enhanced dust storm characterization. KEYWORDS: Climate, Dust, PM, Morbidity

Status of TNF-α and IL-6 as pro-inflammatory cytokines in exhaled breath condensate of late adolescents with asthma and healthy in the dust storm and non-dust storm conditions.

Exposure to airborne particulate matter (PM) can be considered as an important risk factor for human health. Some cytokines have been recognized as the biomarkers of exposure to air pollution. Experimental studies indicate that PM exposure could be associated with inflammation. Thus, the purpose of this study was to evaluate whether the exposure to air PM is associated with biomarkers of inflammation. The specific aim of this study was to determine the correlation between airborne PM levels and IL-6 and TNF-α as airway inflammation biomarkers among two groups of late adolescents in northwest of Iran. This study included 46 subjects, comprising 23 asthmatic subjects and 23 non-asthmatic persons. Environmental PM (PM10, PM2.5 and PM1) levels were measured in dust storm and non-dust storm days during both cold and warm seasons. Following the sampling of PM, Two pro-inflammatory cytokines of IL-6 and TNF-α in exhaled breath condensate (EBC) were also determined in the EBC samples via commercial ELISA kits. Daily mean ambient air PM10, PM2.5 and PM1 concentrations during the dust storm days was 221.79, 93.13 and 25.52 μg m-3 and in non-dusty days 48.37, 18.54 and 6.1 μg m-3, respectively. Biomarkers levels were significantly (p < 0.001) higher in asthmatic students compared to the non-asthmatic subjects. EBC cytokines levels were increased in dust storm days compared to the non-dusty days (p < 0.001) and were positively correlated with different size of ambient PM concentration. Dust storm conditions can increase the pro-inflammatory cytokines and cause adverse effects on pulmonary health and lung tissue damage.

Variation Characteristics and Potential Sources of the Mt. Haituo Aerosol Chemical Composition in Different Pollution Processes During Winter in Beijing, China

In order to investigate the chemical composition and source apportionment of aerosols during winter in the Beijing-Tianjin-Heibei region, the particular matter (PM) and aerosol chemical composition at Mt. Haituo were observed by using a GRIMM 180, a single-particle soot photometer (SP2), and a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS) from December 28, 2020 to February 3, 2021. Combining these observations with meteorological data and the HYSPLIT model, we calculated the potential source contribution factor (PSCF) and concentration weighted trajectory (CWT) and analyzed the temporal evolution and potential sources apportionment of PM and aerosol chemical composition under different pollution processes. The results showed that the dust storm process mainly affected PM10 and PM2.5 in Mt. Haituo during the winter and had a small impact on PM1; by contrast, haze pollution mainly affected PM1. Chemical components of aerosol accounted for 85.0% and 73.4% of PM1 on clean and haze days, respectively, but only 47.4% of PM1 in dust storm processes. NO3- was the chemical component with the largest mass concentration in haze, accounting for 25.2% of PM1; black carbon (BC) had the largest mass concentration on clean and dust storm days, accounting for 24.1% and 12.8% of PM1, respectively. The median diameters of BC were 209.7, 207.5, and 204.7 nm on clean, dust storm, and haze days, respectively. Dp/Dc was 2.15 in haze pollution, which was 1.38 and 1.39 times that on dust storm and clean days, respectively. Diurnal variations in PM and aerosol chemical components were different during the different processes. PM10 and PM2.5had high mass concentrations at night and low mass concentrations during the daytime on clean and dust storm days and had a unimodal distribution with a peak at 14:00 in haze. Diurnal variations in chemical composition had a unimodal distribution on clean days and a bimodal distribution on dust storm and haze days. The chemical compositions of the BC coating layer were different under different processes. The coating layers of BC were mainly NH4NO3, (NH4)2SO4, and organic matter on the clean, dust storm, and haze days, respectively. The distribution of potential sources of PM1 and its chemical components were different under different processes. The high-value area of the potential sources was mainly concentrated in the Beijing-Baoding-Shijiazhuang-Yangquan area in the southwestern portion of the site during dust storms and was mainly concentrated in Yanqing, Huailai, and Changping in the areas around the site during haze.

Effects of the Karkheh Dam construction on haze generation due to geomorphological changes in the Khuzestan Province, Southwest Iran

Abstract The construction of the Karkheh Dam is an important factor contributing to the occurrence of dust storms in the Khuzestan Province of Iran. It has reduced the annual mean flow discharge in the Karkheh River from 120 to 50 m3/s and dried land around the river. The area of dried land is 90.17 km2 around the river and 333.45 km2 in the Hawr-al-Azim wetland. The Rosgen method, Fluvial-12 software, and Shulits equation demonstrate the instability of the plan, cross sections and longitudinal slope of the river, respectively, around Pay-e-pol hydrometric station (upstream of the river). After dam construction, extreme erosion occurred in this part of the river. The type of sediment is clay and silt with D50 = 8 μm. The eroded sediment settles downstream (around Hamidiyeh hydrometric station) and the Hawr-al-Azim wetland. The wind can easily lift these particles especially from May to July. Because of the size of these particles, the haze concentration increased from 25% to 45% in dust storms. After construction of the dam, the dust storm days increased to 90 days in 2008. By increasing the stability of the river, the dust storms reduced from 2011. The annual volume of generated haze by geomorphological characteristic changes is almost 3107 m3.

Assessment of Aerosol Mechanisms and Aerosol Meteorology Feedback over an Urban Airshed in India Using a Chemical Transport Model

The direct aerosol-radiative effects in the WRF-Chem model account for scattering/absorption of solar radiation due to aerosols, while aerosol–cloud interactions result in modifying wet scavenging of the ambient concentrations as an indirect aerosol effect. In this study, impact of aerosol on meteorological parameters, PM10 and ozone concentrations are analysed which revealed (i) that a net decrease in shortwave and longwave radiation by direct feedback results in decrease in temperature up to 0.05 K, (ii) that a net increase due to longwave and shortwave radiation when both direct and indirect effects are taken together results in an increase in temperature up to 0.25 K (where the mean of temperature is 33.5 °C and standard deviation 2.13 °C), (iii) a marginal increase in boundary layer height of 50 m with increase in temperature with feedbacks, (iv) overall net increase in radiation by direct and indirect effect together result in an increase in PM10 concentration up to 12 μg m−3 (with PM10 mean as 84.5 μg m−3 and standard deviation 28 μg m−3) and an increase in ozone concentration up to 3 μg m−3 (with ozone mean as 29.65 μg m−3 and standard deviation 5.2 μg m−3) mainly due to net increase in temperature. Furthermore, impact of sensitivity of different aerosol mechanisms on PM10 concentrations was scrutinized for two different mechanisms that revealed underestimation by both of the mechanisms with MOSAIC scheme, showing less fractional bias than MADE/SORGAM. For the dust storm period, MOSAIC scheme simulated higher mass concentrations than MADE/SORGAM scheme and performed well for dust-storm days while closely capturing the peaks of high dust concentrations. This study is one of the first few to demonstrate the impact of both direct and indirect aerosol feedback on local meteorology and air quality using a meteorology–chemistry modelling framework; the WRF-Chem model in a tropical urban airshed in India located in semi-arid climatic zone. It is inferred that semi-arid climatic conditions behave in a vastly different manner than other climatic zones for direct and indirect radiative feedback effects.

Sixteen years analysis of PM2.5 and mortality in Kuwait

BACKGROUND AND AIM: Middle Eastern desert countries like Kuwait are notoriously known for dramatic dust storms and enormous petrochemical industries affecting ambient air pollution. However, local health authorities have not been able to assess health impacts of air pollution due to limited monitoring networks and lack of historical exposure data. We aimed to estimate the relationship between estimated historical fine particulate matter (PM2.5) and mortality in Kuwait stratified by cause, gender and age. METHODS: We developed a novel approach using machine learning and remote sensing to estimate spatially and temporally resolved daily urban PM2.5 exposures from 2001 to 2016 in the country. We then used over-dispersed generalized additive models to investigate the association with cause-specific, gender- and age-stratified mortality timeseries. RESULTS:There was a total of 70,321 deaths during the study period of 16 years. The average urban PM2.5 was estimated to be 46.2±19.8 µg/m3. A 10 µg/m3 increase in a 5-day moving average of urban PM2.5 was associated with 1.31% (95% CI: 0.56 to 2.07%) increase in all-cause mortality and a 1.15% (0.13 to 2.18%) increase in daily cardiovascular deaths. The corresponding associations among males and females were 1.23% (0.29 to 2.17%) and 1.44% (0.33 to 2.56%), respectively. For the elderly (above 65 years) there was a 1.23% (0.15 to 2.31%) increase in all-cause mortality. The associations were unchanged after adjusting for dust storm days. CONCLUSIONS:We leveraged available pollution, weather and remote sensing data to predict historical PM2.5 with high temporal and spatial resolution. Urban PM2.5 concentrations were above the international regulatory limits. Our findings suggest that, PM2.5 is associated with increased mortality across different strata of the Kuwaiti population. The approach we used can be implemented in other countries that lack historical pollution data or those with insufficient monitoring networks. KEYWORDS: Desert, Dust storm, Kuwait, Middle East, Air Pollution, Machine Learning

Spatial Analysis of the Temporal Long-Term Variations in Frequency of Dust Storm Days in Iran

Spatial Analysis of the Temporal Long-Term Variations in Frequency of Dust Storm Days in Iran

Analysis of Correlation and Coupling between El Niño-Southern Oscillation and Dust Storms in Iraq from 1971 to 2016

This study's main objective is to examine the impact of the El Niño-Southern Oscillation on dust storms in Iraq and trying to find a reasonable synoptic explanation of this relationship. In order to achieve our goal, various data collections related to dust storm days from eight stations in Iraq and the El Niño-Southern Oscillation data over the period 1971–2016 were analyzed. The results showed a negative relationship between dust storms and the El Niño-Southern Oscillation. This correlation means high dust storms are associated with La Niña, while the low dust storms occur during the El Niño event. The coupling between the tropical pacific sector and dust storms in Iraq is perhaps related to the El Niño-Southern Oscillation variations and how they can contribute to the change of the main pressure system values that mainly participate in triggering dust storms and their intensity. The subtropical high-pressure and the Indian monsoon low-pressure systems have been recognized as the responsible pressure systems for dust storms formation.

Aerosol optical properties over Delhi during a dust event in summer 2014: plausible implications

Delhi experiences frequent dust storms during the pre-monsoon season. We studied one such event that occurred on May 30th, 2014 at New Delhi to understand the changes in the optical properties of aerosols. The present study utilizes the aerosol optical depth (AOD) from the ground and satellite measurements along with reanalysis data. The aerosol characteristics were examined during the pre-week and post-week of the dust storm event. The results show that AOD values reach ~ 1.0 in all the modes of measurements (i.e., sun photometer, MODIS, and MERRA-2) on the dust event day. MODIS-derived Aerosol Angstrom Exponent (AAE), which gradually decreases from 1.7 ± 0.3 to 1.1 ± 0.3, shows the presence of coarse mode particles during the event. The aerosol layer at an elevation from 1 to 2 km was observed using indigenously developed dual-polarization micro-pulse lidar (MPL) system during the dust event. The source of the dust during the storm was identified by the air mass back-trajectories analysis. The dust column mass density averaged 24 hourly at 850 hPa is 780 mg m−2 with a prevailing wind direction of west to east with wind speed of 11–13 ms−1. Shortwave aerosol direct radiative forcing (SWADRF) diurnally averaged at the top of the atmosphere (TOA), the atmosphere (ATM), and surface (SUR) are found to be − 10 W m−2, 27 W m−2, and − 37 W m−2, respectively. The heating rate was enhanced by 56% (from 0.16 to 0.25 K day−1) during the event in the whole atmospheric column. Visibility decreased by 31% during the dust storm day compared with its average value of non-dust storm days.

Increases in the formation of water soluble organic nitrogen during Asian dust storm episodes

There is increasing interest in understanding the origin of atmospheric sources of water soluble organic nitrogen (WSON) and its impact on anthropogenic nutrient pollution for terrestrial and marine ecosystem. This study aims to investigate the role of Asian dust storm on atmospheric water soluble organic nitrogen. PM2.5 samples were collected simultaneously from April 1 to May 21, 2012 at the urban area of Zhangjiakou, Hebei province and the rural area of Tianjin near the coastal line, respectively. PM2.5 mass and chemical compositions including ions, total metals, WSON, organic carbon and elemental carbon were adopted for source apportionment using receptor modeling. The sources of PM2.5 mass at the two sampling sites were coal combustion, secondary source, industrial source, mobile source, dust source and biomass burning. The Asian dust storm was observed at the two sampling sites from April 25 to 28, 2012. Significant increases in WSON concentration from ~1.6 μg m−3 to 12 μg m−3 were found at the urban site (S1), and from ~1.3 μg m−3 to 18 μg m−3 at the coastal site (S2), respectively. Source apportionment results showed that the contributions to WSON from dust source increased from ~10% during normal days to ~45% during dust storm days, while the contributions from other sources kept relative stable (<5%) within normal days and dust storm days. The largest sources contributing to WSON at the two sampling sites were secondary sources and fuel combustions. Our study highlights the important role of Asian dust storm in the cycles of WSON in urban and coastal environments.

Origin and Transport Pathway of Dust Storm and Its Contribution to Particulate Air Pollution in Northeast Edge of Taklimakan Desert, China

The Taklimakan Desert in Northwest China is the major source of dust storms in China. The northeast edge of this desert is a typical arid area which houses a fragile oasis eco-environment. Frequent dust storms cause harmful effects on the oasis ecosystem and negative impacts on agriculture, transportation, and human health. In this study, the major source region, transport pathway, and the potential contribution of dust storms to particulate air pollution were identified by using both trajectory analysis and monitoring data. To assess the source regions of dust storms, 48 h backward trajectories of air masses arriving at the Bugur (Luntai) County, which is located at the northeast edge of Taklimakan Desert, China on the dusty season (spring) and non-dusty month (August, representing non-dusty season) in the period of 1999–2013, were determined using Hybrid Single Particle Lagrangian Integrated Trajectory model version 4 (HYSPLIT 4). The trajectories were categorized by k-means clustering into 5 clusters (1a–5a) in the dusty season and 2 clusters (1b and 2b) in the non-dusty season, which show distinct features in terms of the trajectory origins and the entry direction to the site. Daily levels of three air pollutants measured at a station located in Bugur County were analyzed by using Potential Source Contribution Function (PSCF) for each air mass cluster in dusty season. The results showed that TSP is the major pollutant, with an average concentration of 612 µg/m3, as compared to SO2 (23 µg/m3) and NO2 (32 µg/m3) in the dusty season. All pollutants were increased with the dust weather intensity, i.e., from suspended dust to dust storms. High levels of SO2 and NO2 were mostly associated with cluster 1a and cluster 5a which had trajectories passing over the anthropogenic source regions, while high TSP was mainly observed in cluster 4a, which has a longer pathway over the shifting sand desert area. Thus, on strong dust storm days, not only higher TSP but also higher SO2 and NO2 levels were observed as compared to normal days. The results of this study could be useful to forecast the potential occurrence of dust storms based on meteorological data. Research focusing on this dust-storm-prone region will help to understand the possible causes for the changes in the dust storm frequency and intensity, which can provide the basis for mitigation of the negative effects on human health and the environment.

Investigating the culturable atmospheric fungal and bacterial microbiome in West Texas: implication of dust storms and origins of the air parcels.

Individuals often experience ailments such as allergies, asthma and respiratory tract infections throughout the year. Weather reports often include estimations of common allergens that can affect these individuals. To describe the local 'atmospheric microbiome' in Lubbock, Texas, USA, we examined the culturable fungal and bacterial microbiome present in the air on calm and dust storm days using internal transcribed spacer (ITS)-1 and 16S rRNA amplicon sequencing, respectively. While some types of airborne fungi were frequently present throughout the year, distinct differences were also observed between calm and dust storm days. We also observed the influence of the origin of air parcels and wind elevation of the air trajectory. The most abundant genera of fungi identified during the study period were Cryptococcus, Aureobasidium, Alternaria, Cladosporium and Filobasidium. This observation was not surprising considering the agricultural intensive environment of West Texas. Interestingly, Cladosporium, a common allergenic mold, was increased during days with dust storm events. The predominant bacterial genera observed were Bacillus, Pseudomonas, Psychrobacter, Massilia and Exiguobacterium. The relative abundance of the psychrophiles, Psychrobacter and Exiguobacterium, was surprising, given the semi-aridity of West Texas. Coupling our observations with back trajectories of the wind (Hybrid Single-Particle Lagrangian Integrated Trajectory models) demonstrated that dust storms, regional anthropogenic activity and origin of air parcels are important influences on the diversity and temporal presence of the atmospheric microbiome.

Assessment performance parameters correlation of a grid-connected PV system

The primary objective of this examination is to show the impact of climate conditions on grid-connected photovoltaic (PV) framework execution introduced in the Saharan territory of south Algeria (Adrar). This area is described by high surrounding temperature in the late spring, solid sun-based insolation potential and low moistness rate. The information estimation was done in Zaouiet Kounta in different day by day climatic conditions (clear, shady and Dust storm day). The presentation assessment dependent on the checking of execution parameters, for example, last yield, reference yield, execution proportion and Framework proficiency. The got outcomes demonstrate that the framework execution predominantly influenced by the natural changes.