scholarly journals Estimations of anthropogenic dust emissions at global scale from 2007 to 2010

2017 ◽  
Author(s):  
Siyu Chen ◽  
Jianping Huang ◽  
Nanxuan Jiang ◽  
Zhou Zang ◽  
Xiaodan Guan ◽  
...  
Keyword(s):  
Rural Areas ◽  
Urban Areas ◽  
Eastern China ◽  
Dust Emission ◽  
Global Scale ◽  
Dust Particles ◽  
Dust Emissions ◽  
Carbon Cycles ◽  
A Value ◽  
Spatio Temporal

Abstract. Dust emissions refer to the spatial displacement of dust particles from wind forcing, which is a key component of dust circulation. It plays an important role in the energy, hydrological, and carbon cycles of the Earth's systems. However, most dust emission schemes only consider natural dust, neglecting anthropogenic dust induced by human activities, which led to large uncertainties in quantitative estimations of dust emissions in numerical modeling. To fully consider the mechanisms of anthropogenic dust emissions, both indirect and direct anthropogenic dust emission schemes were constructed and developed in the study. Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) retrievals were used to constrain the simulations at global scale. The results showed that the schemes reasonably reproduced the spatio-temporal distributions of anthropogenic dust from 2007 to 2010. The high centers of anthropogenic dust emission flux appeared in India, eastern China, North America, and Africa range from 0.9 to 11 μg m−2 s−1. Compared with natural dust emissions, indirect anthropogenic dust emissions have indistinctive seasonal variation, with differences less than 3.2 μg m−2 s−1. Pasturelands contribute higher anthropogenic dust emissions than croplands, with emissions of approximately 6.8 μg m−2 s−1, accounting for 60 % of indirect anthropogenic dust emissions. Moreover, average anthropogenic dust emissions in urban areas have a value of 13.5 μg m−2 s−1, which is higher than those in rural areas (7.9 μg m−2 s−1). This study demonstrates that the environmental problems caused by anthropogenic dust in urban areas cannot be ignored.

scholarly journals Seasonal patterns of dengue incidence in Thailand across the urban-rural gradient

2020 ◽  
Author(s):  
Qifang Bi ◽  
Derek AT Cummings ◽  
Nicholas G. Reich ◽  
Lindsay T. Keegan ◽  
Joshua Kaminsky ◽  
...  
Keyword(s):  
Wavelet Analysis ◽  
Temporal Variation ◽  
Rural Areas ◽  
Urban Areas ◽  
Dynamic Models ◽  
Seasonal Patterns ◽  
Disease Dynamics ◽  
Urban Rural ◽  
Spatio Temporal ◽  
Dengue Epidemics

AbstractIn Southeast Asia, endemic dengue follows strong spatio-temporal patterns with major epidemics occurring every 2-5 years. However, important spatio-temporal variation in seasonal dengue epidemics remains poorly understood. Using 13 years (2003-2015) of dengue surveillance data from 926 districts in Thailand and wavelet analysis, we show that rural epidemics lead urban epidemics within a dengue season, both nationally and within health regions. However, local dengue fade-outs are more likely in rural areas than in urban areas during the off season, suggesting rural areas are not the source of viral dispersion. Simple dynamic models show that stronger seasonal forcing in rural areas could explain the inconsistency between earlier rural epidemics and dengue “over wintering” in urban areas. These results add important nuance to earlier work showing the importance of urban areas in driving multi-annual patterns of dengue incidence in Thailand. Feedback between geographically linked locations with markedly different ecology is key to explaining full disease dynamics across urban-rural gradient.

scholarly journals Regional Variations of Land-Use Development and Land-Use/Cover Change Dynamics: A Case Study of Turkey

2019 ◽  
Vol 11 (7) ◽  
pp. 885 ◽  
Author(s):  
Ustaoglu ◽  
Aydınoglu
Keyword(s):  
Land Use ◽  
Land Use Change ◽  
Rural Areas ◽  
Urban Areas ◽  
Urban Land ◽  
Temporal Changes ◽  
Rapid Expansion ◽  
Land Uses ◽  
Hierarchical Levels ◽  
Spatio Temporal

. Population growth, economic development and rural-urban migration have caused rapid expansion of urban areas and metropolitan regions in Turkey. The structure of urban administration and planning has faced different socio-economic and political challenges, which have hindered the structured and planned development of cities and regions, resulting in an irregular and uneven development of these regions. We conducted detailed comparative analysis on spatio-temporal changes of the identified seven land-use/cover classes across different regions in Turkey with the use of Corine Land Cover (CLC) data of circa 1990, 2000, 2006 and 2012, integrated with Geographic Information System (GIS) techniques. Here we compared spatio-temporal changes of urban and non-urban land uses, which differ across regions and across different hierarchical levels of urban areas. Our findings have shown that peri-urban areas are growing more than rural areas, and even growing more than urban areas in some regions. A deeper look at regions located in different geographical zones pointed to substantial development disparities across western and eastern regions of Turkey. We also employed multiple regression models to explain any possible drivers of land-use change, regarding both urban and non-urban land uses. The results reveal that the three influencing factors-socio-economic characteristics, regional characteristics and location, and development constraints, facilitate land-use change. However, their impacts differ in different geographical locations, as well as with different hierarchical levels.

scholarly journals The spatial distribution of mineral dust and its shortwave radiative forcing over North Africa: modeling sensitivities to dust emissions and aerosol size treatments

2010 ◽  
Vol 10 (18) ◽  
pp. 8821-8838 ◽  
Author(s):  
C. Zhao ◽  
X. Liu ◽  
L. R. Leung ◽  
B. Johnson ◽  
S. A. McFarlane ◽  
...  
Keyword(s):  
North Africa ◽  
Radiative Forcing ◽  
Mineral Dust ◽  
Regional Climate ◽  
Dust Emission ◽  
Radiative Properties ◽  
Lower Atmosphere ◽  
Dust Particles ◽  
Dust Emissions ◽  
Sahel Region

Abstract. A fully coupled meteorology-chemistry-aerosol model (WRF-Chem) is applied to simulate mineral dust and its shortwave (SW) radiative forcing over North Africa. Two dust emission schemes (GOCART and DUSTRAN) and two aerosol models (MADE/SORGAM and MOSAIC) are adopted in simulations to investigate the modeling sensitivities to dust emissions and aerosol size treatments. The modeled size distribution and spatial variability of mineral dust and its radiative properties are evaluated using measurements (ground-based, aircraft, and satellites) during the AMMA SOP0 campaign from 6 January to 3 February of 2006 (the SOP0 period) over North Africa. Two dust emission schemes generally simulate similar spatial distributions and temporal evolutions of dust emissions. Simulations using the GOCART scheme with different initial (emitted) dust size distributions require ~40% difference in total emitted dust mass to produce similar SW radiative forcing of dust over the Sahel region. The modal approach of MADE/SORGAM retains 25% more fine dust particles (radius<1.25 μm) but 8% less coarse dust particles (radius>1.25 μm) than the sectional approach of MOSAIC in simulations using the same size-resolved dust emissions. Consequently, MADE/SORGAM simulates 11% higher AOD, up to 13% lower SW dust heating rate, and 15% larger (more negative) SW dust radiative forcing at the surface than MOSAIC over the Sahel region. In the daytime of the SOP0 period, the model simulations show that the mineral dust heats the lower atmosphere with an average rate of 0.8 ± 0.5 K day−1 over the Niamey vicinity and 0.5 ± 0.2 K day−1 over North Africa and reduces the downwelling SW radiation at the surface by up to 58 W m−2 with an average of 22 W m−2 over North Africa. This highlights the importance of including dust radiative impact in understanding the regional climate of North Africa. When compared to the available measurements, the WRF-Chem simulations can generally capture the measured features of mineral dust and its radiative properties over North Africa, suggesting that the model is suitable for more extensive simulations of dust impact on regional climate over North Africa.

scholarly journals Implementation of dust emission and chemistry into the Community Multiscale Air Quality modeling system and initial application to an Asian dust storm episode

2012 ◽  
Vol 12 (21) ◽  
pp. 10209-10237 ◽  
Author(s):  
K. Wang ◽  
Y. Zhang ◽  
A. Nenes ◽  
C. Fountoukis
Keyword(s):  
Air Quality ◽  
Dust Storm ◽  
Dust Emission ◽  
Forecast Model ◽  
Heterogeneous Reactions ◽  
Dust Particles ◽  
Aerodynamic Diameter ◽  
Dust Emissions ◽  
New Model ◽  
The Impact

Abstract. The US Environmental Protection Agency's (EPA) Community Multiscale Air Quality (CMAQ) modeling system version 4.7 is further developed to enhance its capability in simulating the photochemical cycles in the presence of dust particles. The new model treatments implemented in CMAQ v4.7 in this work include two online dust emission schemes (i.e., the Zender and Westphal schemes), nine dust-related heterogeneous reactions, an updated aerosol inorganic thermodynamic module ISORROPIA II with an explicit treatment of crustal species, and the interface between ISORROPIA II and the new dust treatments. The resulting improved CMAQ (referred to as CMAQ-Dust), offline-coupled with the Weather Research and Forecast model (WRF), is applied to the April 2001 dust storm episode over the trans-Pacific domain to examine the impact of new model treatments and understand associated uncertainties. WRF/CMAQ-Dust produces reasonable spatial distribution of dust emissions and captures the dust outbreak events, with the total dust emissions of ~111 and 223 Tg when using the Zender scheme with an erodible fraction of 0.5 and 1.0, respectively. The model system can reproduce well observed meteorological and chemical concentrations, with significant improvements for suspended particulate matter (PM), PM with aerodynamic diameter of 10 μm, and aerosol optical depth than the default CMAQ v4.7. The sensitivity studies show that the inclusion of crustal species reduces the concentration of PM with aerodynamic diameter of 2.5 μm (PM2.5) over polluted areas. The heterogeneous chemistry occurring on dust particles acts as a sink for some species (e.g., as a lower limit estimate, reducing O3 by up to 3.8 ppb (~9%) and SO2 by up to 0.3 ppb (~27%)) and as a source for some others (e.g., increasing fine-mode SO42− by up to 1.1 μg m−3 (~12%) and PM2.5 by up to 1.4 μg m−3 (~3%)) over the domain. The long-range transport of Asian pollutants can enhance the surface concentrations of gases by up to 3% and aerosol species by up to 20% in the Western US.

scholarly journals Suppression of Soil Dust Emissions from Large-Scale Construction Sites Using Starch and Polyvinyl Alcohol

2019 ◽  
Vol 8 (2) ◽  
pp. 38-46
Author(s):  
Jong-Soo Choi ◽  
Dong-Su Kim ◽  
Yu-Lim Choi ◽  
Lakshmi Prasanna Lingamdinne ◽  
Janardhan Reddy Koduru ◽  
...  
Keyword(s):  
Polyvinyl Alcohol ◽  
Urban Areas ◽  
Large Scale ◽  
Dust Emission ◽  
Aggregate Stability ◽  
Scale Construction ◽  
Soil Dust ◽  
Construction Sites ◽  
Limit Values ◽  
Dust Emissions

Soil dust emitted from large-scale construction sites in urban areas impacts air quality and creates a severe health threat to residents. Water spraying is commonly practiced to lower dust emission in construction sites, but its long-term effectiveness is questionable. In this study the utility of starch, polyvinyl alcohol (PVA), and a blend of starch and PVA in various proportions was investigated for the suppression of soil dust emissions at construction sites in Seoul. The efficiency of each dust suppressant was tested with test soil samples in a laboratory-scale wind tunnel box under different concentrations of suppressants and soil textures. Starch and PVA showed superior ability to suppress soil dust emissions compared to moistening bare soil, resulting in PM10 lower than the daily limit values of 30 μg/m3. PVA showed higher soil dust suppression capability for all conditions over starch. Test soils sprayed with dust suppressants significantly improved aggregate stability compared to untreated soils.

scholarly journals Retrieving High-Resolution Aerosol Optical Depth from GF-4 PMS Imagery in Eastern China

2021 ◽  
Vol 13 (18) ◽  
pp. 3752
Author(s):  
Zhendong Sun ◽  
Jing Wei ◽  
Ning Zhang ◽  
Yulong He ◽  
Yu Sun ◽  
...  
Keyword(s):  
Aerosol Optical Depth ◽  
Optical Depth ◽  
Zenith Angle ◽  
Rural Areas ◽  
Urban Areas ◽  
Eastern China ◽  
Practical Significance ◽  
Retrieval Algorithm ◽  
Transfer Model ◽  
Surface Reflectance

Gaofen 4 (GF-4) is a geostationary satellite, with a panchromatic and multispectral sensor (PMS) onboard, and has great potential in observing atmospheric aerosols. In this study, we developed an aerosol optical depth (AOD) retrieval algorithm for the GF-4 satellite. AOD retrieval was realized based on the pre-calculated surface reflectance database and 6S radiative transfer model. We customized the unique aerosol type according to the long time series aerosol parameters provided by the Aerosol Robotic Network (AERONET) site. The solar zenith angle, relative azimuth angle, and satellite zenith angle of the GF-4 panchromatic multispectral sensor image were calculated pixel-by-pixel. Our 1 km AOD retrievals were validated against AERONET Version 3 measurements and compared with MOD04 C6 AOD products at different resolutions. The results showed that our GF-4 AOD algorithm had a good robustness in both bright urban areas and dark rural areas. A total of 71.33% of the AOD retrievals fell within the expected errors of ±(0.05% + 20%); root-mean-square error (RMSE) and mean absolute error (MAE) were 0.922 and 0.122, respectively. The accuracy of GF-4 AOD in rural areas was slightly higher than that in urban areas. In comparison with MOD04 products, the accuracy of GF-4 AOD was much higher than that of MOD04 3 km and 10 km dark target AOD, but slightly worse than that of MOD04 10 km deep blue AOD. For different values of land surface reflectance (LSR), the accuracy of GF-4 AOD gradually deteriorated with an increase in the LSR. These results have theoretical and practical significance for aerosol research and can improve retrieval algorithms using the GF-4 satellite.

scholarly journals Implementation of dust emission and chemistry into the Community Multiscale Air Quality modeling system and initial application to an Asian dust storm episode

2012 ◽  
Vol 12 (5) ◽  
pp. 13457-13514 ◽  
Author(s):  
K. Wang ◽  
Y. Zhang ◽  
A. Nenes ◽  
C. Fountoukis
Keyword(s):  
Air Quality ◽  
Dust Storm ◽  
Dust Emission ◽  
Heterogeneous Reactions ◽  
Dust Particles ◽  
Aerodynamic Diameter ◽  
Dust Emissions ◽  
New Model ◽  
The Us ◽  
The Impact

Abstract. The US Environmental Protection Agency (EPA)'s Community Multiscale Air Quality (CMAQ) modeling system version 4.7 is further developed to enhance its capability in simulating the photochemical cycles in the presence of dust particles. The new model treatments implemented in CMAQ v4.7 in this work include two online-dust emission schemes, nine dust-related heterogeneous reactions, an updated aerosol inorganic thermodynamic module ISORROPIA II with an explicit treatment of crustal species, and the interface between ISORROPIA II and the new dust treatments. The resulting improved CMAQ (referred to as CMAQ-Dust), offline-coupled with the Weather Research and Forecast model (WRF), are applied to the April 2001 dust storm episode over the trans-Pacific domain to examine the impact of new model treatments and understand associated uncertainties. WRF/CMAQ-Dust produces reasonable spatial distribution of dust emissions and captures the dust outbreak events, with the total dust emissions of ∼111 and 223 Tg when the erodible fraction is assumed to be 0.5 and 1.0, respectively, for the April 2001 episode. The model system can reproduce well observed meteorological and chemical concentrations, with significant improvements for suspended particulate matter (PM), PM with aerodynamic diameter of 10 μm and aerosol optical depth than default CMAQ v4.7. The sensitivity studies show that the inclusion of crustal species reduces the concentration of PM with aerodynamic diameter of 2.5 μm (PM2.5) over polluted areas. The heterogeneous chemistry occurring on dust particles acts as a sink for some species (e.g., as a lower limit estimate, O3 by up to 3.8 ppb (∼9%) and SO2 by up to 0.3 ppb (∼27%)) and as a source for some others (e.g., fine-mode SO42− by up to 1.1 μg m−3 (∼12%) and PM2.5 by up to 1.4 μg m−3 (∼3%) over the domain. The long-range transport of Asian pollutants can enhance the background concentrations of gases by up to 3% and aerosol species by up to 20% in the US.

scholarly journals Sensitivity of the WRF-Chem (V3.6.1) model to different dust emission parametrisation: assessment in the broader Mediterranean region

2017 ◽  
Vol 10 (8) ◽  
pp. 2925-2945 ◽  
Author(s):  
Emmanouil Flaounas ◽  
Vassiliki Kotroni ◽  
Konstantinos Lagouvardos ◽  
Martina Klose ◽  
Cyrille Flamant ◽  
...  
Keyword(s):  
North Africa ◽  
Eastern Mediterranean ◽  
Dust Emission ◽  
Model Performance ◽  
Dust Particles ◽  
Dust Transport ◽  
Dust Emissions ◽  
Extinction Coefficients ◽  
Airborne Measurements ◽  
Model Aerosol

Abstract. In this study we aim to assess the WRF-Chem model capacity to reproduce dust transport over the eastern Mediterranean. For this reason, we compare the model aerosol optical depth (AOD) outputs to observations, focusing on three key regions: North Africa, the Arabian Peninsula and the eastern Mediterranean. Three sets of four simulations have been performed for the 6-month period of spring and summer 2011. Each simulation set uses a different dust emission parametrisation and for each parametrisation, the dust emissions are multiplied with various coefficients in order to tune the model performance. Our assessment approach is performed across different spatial and temporal scales using AOD observations from satellites and ground-based stations, as well as from airborne measurements of aerosol extinction coefficients over the Sahara. Assessment over the entire domain and simulation period shows that the model presents temporal and spatial variability similar to observed AODs, regardless of the applied dust emission parametrisation. On the other hand, when focusing on specific regions, the model skill varies significantly. Tuning the model performance by applying a coefficient to dust emissions may reduce the model AOD bias over a region, but may increase it in other regions. In particular, the model was shown to realistically reproduce the major dust transport events over the eastern Mediterranean, but failed to capture the regional background AOD. Further comparison of the model simulations to airborne measurements of vertical profiles of extinction coefficients over North Africa suggests that the model realistically reproduces the total atmospheric column AOD. Finally, we discuss the model results in two sensitivity tests, where we included finer dust particles (less than 1 µm) and changed accordingly the dust bins' mass fraction.

Numerical simulations of anthropogenic dust

2021 ◽  
Author(s):  
Siyu Chen
Keyword(s):  
Wind Erosion ◽  
Agricultural Land ◽  
Premature Mortality ◽  
Global Scale ◽  
Developing Regions ◽  
Dust Emissions ◽  
Source Regions ◽  
Crucial Component ◽  
Spatio Temporal ◽  
High Concentrations

&lt;p&gt;Approximately 90% of people worldwide breathe air that contains&amp;#160;high concentrations of particulate matter (PM) pollution. Anthropogenic dust (AD), as a crucial component of PM, can be interpreted as dust emitted by modifying or disturbing soil particles through direct (e.g., construction and driving of vehicles) and indirect (e.g., wind erosion over agricultural land, grassland, dry lakes, etc.) human activities. The compositions and properties of AD are more complex and variable than those of natural dust (ND). Current studies on dust aerosols have mostly focused on ND emissions, transport, and climate effects. However, the quantitative knowledge of the sources, characteristics, and impacts of AD is inadequate.&lt;/p&gt;&lt;p&gt;To comprehensively reproduce the AD emissions process, both &amp;#8220;indirect&amp;#8221; and &amp;#8220;direct&amp;#8221; AD&amp;#160;emission were constructed to simulate AD&amp;#160;emissions originated from diverse kinds of source regions in the study. Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) retrievals were utilized as the constraint of AD&amp;#160;simulations. Results showed that using both indirect and direct AD&amp;#160;emission schemes show good performance on reproducing the spatio-temporal distributions of AD&amp;#160;at the global scale. Compared with natural dust emissions, indirect AD&amp;#160;emissions show an indistinctive seasonal variation, with seasonal differences generally less than 0.42 &amp;#956;g m&lt;sup&gt;&amp;#8722;2 &lt;/sup&gt;s&lt;sup&gt;&amp;#8722;1&lt;/sup&gt;. Among indirect AD&amp;#160;emissions, pasturelands produce more AD&amp;#160;particles emission into the atmosphere than croplands at approximately 0.28 &amp;#956;g m&lt;sup&gt;&amp;#8722;2&lt;/sup&gt;&amp;#160;s&lt;sup&gt;&amp;#8722;1&lt;/sup&gt;, contributing 75.9% of indirect AD&amp;#160;emissions. The developing regions emit much higher direct AD&amp;#160;emissions than those from developed regions. In addition, AD-induced surface radiative cooling of up to -10.0 W m&lt;sup&gt;-2&lt;/sup&gt;&amp;#160;regionally, especially in the developing countries. The estimated global total premature mortality due to AD is 0.7&amp;#160;million deaths per year and is more severe in populous regions.&lt;/p&gt;

scholarly journals Scenario Analysis for Incremental Community Planning in an African Context

2020 ◽  
Vol 12 (19) ◽  
pp. 8133
Author(s):  
Santiago Restrepo Arias ◽  
Sara Torabi Moghadam ◽  
Patrizia Lombardi
Keyword(s):  
Rural Areas ◽  
Urban Areas ◽  
Life Quality ◽  
Global Scale ◽  
Preference Ranking ◽  
Documentary Analysis ◽  
Urban Scenario ◽  
African Context ◽  
Evaluation Stage ◽  
Identification Stage

Urban areas are gradually becoming more viable places in terms of life quality than most rural areas. This phenomenon generates human movements, both at a local and at an international scale, the latter usually being labeled as irregular migration. This study aims at analyzing urban scenario proposals that part from incremental urbanism principles to create opportunities for youth and women in the area of Pikine Est (Senegal), a neighborhood with a high vocation toward migration. An integrated planning approach is proposed, where an initial project identification stage reveals through documentary analysis and discussion the adequate project strategies to apply and shines a light on proper life quality indicators (LQIs). In the successive stage, project formulation, future-oriented scenarios are proposed. Finally, at the evaluation stage, each urban scenario is assessed to determine which one contains a more suitable set of strategies in function of the community’s needs, employing multi-criteria analysis (MCA) and preference ranking organization method for enrichment evaluation (PROMETHEE) methods. As a result, this study proves through measurable data that assessing incremental urban interventions makes sense in developing communities, not only as a study of their response to scarce financial resources, but also as means to overcome and avoid environmental issues that cities face at a global scale today.

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