scholarly journals Vehicle Traffic as a Source of CO2, CO, HC and Particulate Polycyclic Aromatic Hydrocarbon in the Mingora City, District Swat, KP, Pakistan and Their Effect on Health, Temperature and Tourism

2021 ◽  
Vol 12 (1) ◽  
pp. 32
Author(s):  
Mian Gul Sayed ◽  
Naeem Ullah ◽  
Shah Khalid ◽  
Fazal Mabood ◽  
Muhammad Naveed Umar

In this work we collected a large number of vehicular emission data of carbon dioxide (CO2), carbon monoxide (CO) and hydrocarbons (HC) from custom paid and non-custom paid vehicles in the Swat district, which are responsible for changing the climate and global warming. Swat valley is facing severe threats and impacts of the climate change as there is a record high increase in the temperature with flash floods and droughts becoming increasingly common. The main cause of the increasing warm weather is vehicle emissions along with the cutting of forest on a large scale in the valley. Hospital records for 2768 children aged 0 to 18 years (697 of whom had two encounters) were obtained for a main city area of two hospitals in Saidu Sharif, Swat. Residential addresses were geocoded. A line source dispersion model was used to estimate individual seasonal exposures to local traffic-generated pollutants (nitrogen oxides, carbon monoxide and hydroxide).

2005 ◽  
Vol 5 (12) ◽  
pp. 3313-3329 ◽  
Author(s):  
M. Buchwitz ◽  
R. de Beek ◽  
S. Noël ◽  
J. P. Burrows ◽  
H. Bovensmann ◽  
...  

Abstract. The near-infrared nadir spectra measured by SCIAMACHY on-board ENVISAT contain information on the vertical columns of important atmospheric trace gases such as carbon monoxide (CO), methane (CH4), and carbon dioxide (CO2). The scientific algorithm WFM-DOAS has been used to retrieve this information. For CH4 and CO2 also column averaged mixing ratios (XCH4 and XCO2) have been determined by simultaneous measurements of the dry air mass. All available spectra of the year 2003 have been processed. We describe the algorithm versions used to generate the data (v0.4; for methane also v0.41) and show comparisons of monthly averaged data over land with global measurements (CO from MOPITT) and models (for CH4 and CO2). We show that elevated concentrations of CO resulting from biomass burning have been detected in reasonable agreement with MOPITT. The measured XCH4 is enhanced over India, south-east Asia, and central Africa in September/October 2003 in line with model simulations, where they result from surface sources of methane such as rice fields and wetlands. The CO2 measurements over the Northern Hemisphere show the lowest mixing ratios around July in qualitative agreement with model simulations indicating that the large scale pattern of CO2 uptake by the growing vegetation can be detected with SCIAMACHY. We also identified potential problems such as a too low inter-hemispheric gradient for CO, a time dependent bias of the methane columns on the order of a few percent, and a few percent too high CO2 over parts of the Sahara.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6507 ◽  
Author(s):  
Jaya Thakur ◽  
Prajesh Thever ◽  
Biswadip Gharai ◽  
MVR Sesha Sai ◽  
VNRao Pamaraju

The richly forested Indian state of Uttarakhand experienced widespread forest fires in April to May 2016. The current study examines dispersion of carbon monoxide (CO) from the source regions of forest fire to distant places, using the Lagrangian particle dispersion model, FLEXPART. Atmospheric Infrared Sounder (AIRS) observations revealed that CO columnar concentrations had increased by almost 28 percentage during 24 April to 02 May 2016 with respect to the previous non-burning period of April 2016 at Uttarakhand. It is also seen that there is considerable enhancement of 45 percentage in average columnar concentration of CO during the burning period, compared to that in the previous 5 years as observed by AIRS. In the present study, concentrations of CO at different pressure levels and columnar CO over Uttarakhand during the forest fire event have been simulated using FLEXPART. The area averaged profile of model derived CO has been compared with the profile from AIRS onboard Aqua. Comparison between model derived columnar CO and satellite observations shows good agreement with coefficient of correlation (r) approximately 0.91 over the burnt areas. Further analysis using FLEXPART reveals that the transport of pollutants is towards north-eastern and eastern regions from the locations of forest fire events. Model derived vertical distribution of CO over Tibet, which is situated at the north-east of Uttarakhand, shows significant increase of CO concentration at higher altitudes around 3 km from the mean sea level during the fire event. FLEXPART results show that the emissions from the Uttarakhand fires were transported to Tibet during the study period.


2021 ◽  
Vol 13 (14) ◽  
pp. 7782
Author(s):  
Wenjing Zeng ◽  
Yongde Zhong ◽  
Dali Li ◽  
Jinyang Deng

The recreation opportunity spectrum (ROS) has been widely recognized as an effective tool for the inventory and planning of outdoor recreational resources. However, its applications have been primarily focused on forest-dominated settings with few studies being conducted on all land types at a regional scale. The creation of a ROS is based on physical, social, and managerial settings, with the physical setting being measured by three criteria: remoteness, size, and evidence of humans. One challenge to extending the ROS to all land types on a large scale is the difficulty of quantifying the evidence of humans and social settings. Thus, this study, for the first time, developed an innovative approach that used night lights as a proxy for evidence of humans and points of interest (POI) for social settings to generate an automatic ROS for Hunan Province using Geographic Information System (GIS) spatial analysis. The whole province was classified as primitive (2.51%), semi-primitive non-motorized (21.33%), semi-primitive motorized (38.60%), semi-developed natural (30.99%), developed natural (5.61%), and highly developed (0.96%), which was further divided into three subclasses: large-natural (0.63%), small natural (0.27%), and facilities (0.06%). In order to implement the management and utilization of natural recreational resources in Hunan Province at the county (city, district) level, the province’s 122 counties (cities, districts) were categorized into five levels based on the ROS factor dominance calculated at the county and provincial levels. These five levels include key natural recreational counties (cities, districts), general natural recreational counties (cities, districts), rural counties (cities, districts), general metropolitan counties (cities, districts), and key metropolitan counties (cities, districts), with the corresponding numbers being 8, 21, 50, 24, and 19, respectively.


2017 ◽  
Vol 107 (10) ◽  
pp. 1175-1186 ◽  
Author(s):  
M. Meyer ◽  
L. Burgin ◽  
M. C. Hort ◽  
D. P. Hodson ◽  
C. A. Gilligan

In recent years, severe wheat stem rust epidemics hit Ethiopia, sub-Saharan Africa’s largest wheat-producing country. These were caused by race TKTTF (Digalu race) of the pathogen Puccinia graminis f. sp. tritici, which, in Ethiopia, was first detected at the beginning of August 2012. We use the incursion of this new pathogen race as a case study to determine likely airborne origins of fungal spores on regional and continental scales by means of a Lagrangian particle dispersion model (LPDM). Two different techniques, LPDM simulations forward and backward in time, are compared. The effects of release altitudes in time-backward simulations and P. graminis f. sp. tritici urediniospore viability functions in time-forward simulations are analyzed. Results suggest Yemen as the most likely origin but, also, point to other possible sources in the Middle East and the East African Rift Valley. This is plausible in light of available field surveys and phylogenetic data on TKTTF isolates from Ethiopia and other countries. Independent of the case involving TKTTF, we assess long-term dispersal trends (>10 years) to obtain quantitative estimates of the risk of exotic P. graminis f. sp. tritici spore transport (of any race) into Ethiopia for different ‘what-if’ scenarios of disease outbreaks in potential source countries in different months of the wheat season.


2011 ◽  
Vol 75 (7) ◽  
pp. 1392-1394 ◽  
Author(s):  
Takahiro INOUE ◽  
Takashi YOSHIDA ◽  
Kei WADA ◽  
Takashi DAIFUKU ◽  
Keiichi FUKUYAMA ◽  
...  

2000 ◽  
Vol 122 (2) ◽  
pp. 403-411 ◽  
Author(s):  
P. W. Longest, ◽  
C. Kleinstreuer ◽  
J. S. Kinsey

Steady incompressible turbulent air flow and transient carbon monoxide transport in an empty Rochester-style human exposure chamber have been numerically simulated and compared with experimental data sets. The system consisted of an inlet duct with a continuous carbon monoxide point source, 45- and 90-degree bends, a round diffuser, a round-to-square transition, a rectangular diffuser, the test chamber, a perforated floor, and again transition pieces from the chamber to an outlet duct. Such a configuration induced highly nonuniform vortical flow patterns in the chamber test area where a pollutant concentration is required to be constant at breathing level for safe and accurate inhalation studies. Presented are validated momentum and mass transfer results for this large-scale system with the main goals of determining the development of tracer gas (CO) distributions in the chamber and analyzing the contributions to CO-mixing. Numerical simulations were conducted employing a k-ε model and the latest available RNG k-ε model for air and CO-mixing. Both models predict similar velocity fields and are in good agreement with measured steady and transient CO-concentrations. It was found that secondary flows in the inlet section and strong vortical flow in the chamber with perforated flooring contributed to effective mixing of the trace gas at breathing levels. Specifically, in the height range of 1.4 m<h<2.0 m above the chamber floor, predicted CO-concentrations rapidly reached a near constant value which agrees well with experimental results. This work can be extended to analyze trace gas mixing as well as aerosol dispersion in occupied test chambers with or without flow redirection devices installed in the upstream section. A complementary application is particle transport and deposition in clean rooms of the electronic, pharmaceutical, and health care industries. [S0098-2202(00)01702-8]


Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 452
Author(s):  
Jan Bitta ◽  
Vladislav Svozilík ◽  
Aneta Svozilíková Krakovská

Land Use Regression (LUR) is one of the air quality assessment modelling techniques. Its advantages lie mainly in a much simpler mathematical apparatus, quicker and simpler calculations, and a possibility to incorporate more factors affecting pollutant concentration than standard dispersion models. The goal of the study was to perform the LUR model in the Polish-Czech-Slovakian Tritia region, to test two sets of pollution data input factors, i.e., factors based on emission data and pollution dispersion model results, to test regression via neural networks and compare it with standard linear regression. Both input datasets, emission data and pollution dispersion model results, provided a similar quality of results in the case when standard linear regression was used, the R2 of the models was 0.639 and 0.652. Neural network regression provided a significantly higher quality of the models, their R2 was 0.937 and 0.938 for the factors based on emission data and pollution dispersion model results respectively.


2021 ◽  
Author(s):  
Kristen Kieta ◽  
Philip Owens ◽  
Ellen Petticrew

&lt;p&gt;The Nechako River Basin (NRB) in central British Columbia is a large (52,000 km&lt;sup&gt;2&lt;/sup&gt;), regulated basin that supports populations of sockeye and chinook salmon and the endangered Nechako white sturgeon. These important species are experiencing population declines and one potential cause of this decline is excess sediment, which can clog their spawning habitat and reduce juvenile success. This excess sediment is likely the product of a combination of factors, the most visible being the significant land cover changes that have occurred in the basin, which includes pressure from forestry and agriculture, the Mountain Pine Beetle epidemic, and large-scale wildfires in 2018. Focusing specifically on the impact of the 2018 wildfires on sediment transport from upland burned areas to adjacent waterways, this research aimed to determine the spatial and temporal contamination of tributaries and the mainstem of the Nechako River with polycyclic aromatic hydrocarbons (PAHs), which are produced during the combustion of organic matter and have been identified as toxic to aquatic organisms and to humans. Additionally, this study intended to determine if burned areas were a more significant contributor of sediment than unburned areas and better understand the utility of PAHs as a potential tracer. Source soil samples were collected in 2018 and 2020 from burned and unburned sites, and suspended sediment samples were collected throughout the ice-free period from 2018-2020 in three tributaries and three mainstem sites. All samples were analysed for PAHs, magnetic susceptibility, colour, and particle size. Results from the fall 2018 source samples show a significant difference in PAH concentrations between unburned and burned soils, and while concentrations of PAHs in source soils in 2020 were lower than in 2018, they were still elevated compared to unburned soils. Sediment samples showed that concentrations of total PAHs are higher in the mainstem sites than in the tributaries, with the greatest concentrations consistently found at the most downstream site on the mainstem of the Nechako River. Concentrations across sites were highest in samples taken during the spring snowmelt period in 2019, have decreased throughout the rest of the sampling period (2019-2020), and are well below sediment quality guidelines for total PAHs. In addition to determining the spatial and temporal extent of PAH contamination, this study also aims to use PAHs along with colour and measurements of magnetic susceptibility to trace sediments associated with the 2018 wildfires. The high cost of PAH analysis limits the number of samples that can be analysed and thus, these additional tracers will allow for the use of models such as MixSIAR that improve with a more robust number of samples. As large-scale megafires continue to burn across the globe, understanding their potential to contribute PAHs to local waterbodies and potentially be used as a tracer is as prescient as ever.&lt;/p&gt;


Sign in / Sign up

Export Citation Format

Share Document