scholarly journals Understanding Spatial Variability of NO2 in Urban Areas Using Spatial Modelling and Data Fusion Approaches

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 179
Author(s):  
Said Munir ◽  
Martin Mayfield ◽  
Daniel Coca
Keyword(s):  
Data Fusion ◽  
Spatial Variability ◽  
Urban Areas ◽  
Road Traffic ◽  
Dispersion Model ◽  
Low Cost ◽  
Spatial Modelling ◽  
City Centre ◽  
Small Scale ◽  
The City

Small-scale spatial variability in NO2 concentrations is analysed with the help of pollution maps. Maps of NO2 estimated by the Airviro dispersion model and land use regression (LUR) model are fused with measured NO2 concentrations from low-cost sensors (LCS), reference sensors and diffusion tubes. In this study, geostatistical universal kriging was employed for fusing (integrating) model estimations with measured NO2 concentrations. The results showed that the data fusion approach was capable of estimating realistic NO2 concentration maps that inherited spatial patterns of the pollutant from the model estimations and adjusted the modelled values using the measured concentrations. Maps produced by the fusion of NO2-LCS with NO2-LUR produced better results, with r-value 0.96 and RMSE 9.09. Data fusion adds value to both measured and estimated concentrations: the measured data are improved by predicting spatiotemporal gaps, whereas the modelled data are improved by constraining them with observed data. Hotspots of NO2 were shown in the city centre, eastern parts of the city towards the motorway (M1) and on some major roads. Air quality standards were exceeded at several locations in Sheffield, where annual mean NO2 levels were higher than 40 µg/m3. Road traffic was considered to be the dominant emission source of NO2 in Sheffield.

scholarly journals A Nonlinear Land Use Regression Approach for Modelling NO2 Concentrations in Urban Areas—Using Data from Low-Cost Sensors and Diffusion Tubes

Atmosphere ◽  
2020 ◽  
Vol 11 (7) ◽  
pp. 736
Author(s):  
Said Munir ◽  
Martin Mayfield ◽  
Daniel Coca ◽  
Lyudmila S Mihaylova
Keyword(s):  
Land Use ◽  
Urban Areas ◽  
Low Cost ◽  
City Centre ◽  
Small Scale ◽  
Land Use Regression ◽  
Diffusion Tubes ◽  
Using Data ◽  
The City ◽  
And Diffusion

Land Use Regression (LUR) based on multiple linear regression model is one of the techniques used most frequently for modelling the spatial variability of air pollution and assessing exposure in urban areas. In this paper, a nonlinear generalised additive model is proposed for LUR and its performance is compared to a linear model in Sheffield, UK for the year 2019. Pollution models were estimated using NO2 measurements obtained from 188 diffusion tubes and 40 low-cost sensors. Performance of the models was assessed by calculating several statistical metrics including correlation coefficient (R) and root mean square error (RMSE). High resolution (100 m × 100 m) maps demonstrated higher levels of NO2 in the city centre, eastern side of the city and on major roads. The results showed that the nonlinear model outperformed the linear counterpart and that the model estimated using NO2 data from diffusion tubes outperformed the models using data from low-cost sensors or both low-cost sensors and diffusion tubes. The proposed method provides a basis for further application of advanced nonlinear modelling approaches to constructing LUR models in urban areas which enable quantifying small scale variability in pollution levels.

scholarly journals Analysis of Air Pollution in Urban Areas with Airviro Dispersion Model—A Case Study in the City of Sheffield, United Kingdom

Atmosphere ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 285 ◽  
Author(s):  
Said Munir ◽  
Martin Mayfield ◽  
Daniel Coca ◽  
Lyudmila S Mihaylova ◽  
Ogo Osammor
Keyword(s):  
Air Pollution ◽  
United Kingdom ◽  
Situation Awareness ◽  
Urban Areas ◽  
Road Traffic ◽  
Dispersion Model ◽  
Point Sources ◽  
Spatiotemporal Variability ◽  
City Centre ◽  
Oxides Of Nitrogen

Two air pollutants, oxides of nitrogen (NOx) and particulate matter (PM10), are monitored and modelled employing Airviro air quality dispersion modelling system in Sheffield, United Kingdom. The aim is to determine the most significant emission sources and their spatial variability. NOx emissions (ton/year) from road traffic, point and area sources for the year 2017 were 5370, 6774, and 2425, whereas those of PM10 (ton/year) were 345, 1449, and 281, respectively, which are part of the emission database. The results showed three hotspots of NOx, namely the Sheffield City Centre, Darnall and Tinsley Roundabout (M1 J34S). High PM10 concentrations were shown mainly between Sheffield Forgemasters International (a heavy engineering steel company) and Meadowhall Shopping Centre. Several emission scenarios were tested, which showed that NOx concentrations were mainly controlled by road traffic, whereas PM10 concentrations were controlled by point sources. Spatiotemporal variability and public exposure to air pollution were analysed. NOx concentration was greater than 52 µg/m3 in about 8 km2 area, where more than 66 thousand people lived. Models validated by observations can be used to fill in spatiotemporal gaps in measured data. The approach used presents spatiotemporal situation awareness maps that could be used for decision making and improving the urban infrastructure.

scholarly journals Green Spaces in Residential Areas of Dar es Salaam City: Types, Coverage and Uses

2021 ◽  
Vol 14 (3) ◽  
pp. 121
Author(s):  
Nicholaus Mwageni ◽  
Robert Kiunsi
Keyword(s):  
Urban Areas ◽  
Green Space ◽  
Dar Es Salaam ◽  
Economic Benefits ◽  
Natural Vegetation ◽  
Green Spaces ◽  
City Centre ◽  
Building Density ◽  
Dar Es Salaam City ◽  
The City

Green spaces in urban areas including in Dar es Salaam City provide multiple ecological, social and economic benefits. Despite their benefits they are inadequately documented in terms types, coverage and uses. This paper attempts to provide information on types, coverage and uses of green space in Dar es Salaam City. A number of methods including literature review, interpretation of remotely sensed image, interviews, focus group discussions and questionnaires were used to document city greenery. The research findings show that residential greenery is made up of greenery found within and external to plots. The dominant green spaces external to residential plots were natural and semi natural vegetation while within plots were woody plants, plots farms vegetable and ornamental gardens. Distribution of greenery varied among the wards due to differences in building density and distance from the city centre. Natural and semi natural vegetation increased with decrease of building density and increase of distance from the city centre, while the number of plots with trees for shade increased with increase of building density. Only Kawe ward that had greenery above Tanzania space planning standards, the other three wards which are informal settlements had green space deficit. Three quarters of the households use green spaces for shade provision and cooling, two thirds as a source of food products and a quarter for recreation and aesthetic purposes. The study reveals that Dar es Salaam City residents invest predominantly on shade trees in their residential plots compared to other green space types.

Urban DAS recording of a vibroseismic campaign with a 21km-long dark fibre in Potsdam, Germany

2021 ◽  
Author(s):  
CharLotte Krawczyk ◽  
Christopher Wollin ◽  
Stefan Lüth ◽  
Martin Lipus ◽  
Christian Cunow ◽  
...  
Keyword(s):  
Urban Areas ◽  
District Heating ◽  
Telecommunication Networks ◽  
Seismic Exploration ◽  
City Centre ◽  
Data Set ◽  
Geothermal Potential ◽  
First Results ◽  
Local Geology ◽  
The City

<p>The de-carbonization strategy of the city of Potsdam, Germany, incorporates the utilization of its geothermal potential.  As a first step of developing a deep geothermal project for district heating, an urban seismic exploration campaign of the Stadtwerke Potsdam took place in December 2020 in the city centre of Potsdam.  Since urban measurements are often difficult to setup and a low-footprint alternative is sought for, we supplemented the contractor-performed Vibroseis survey along three profiles by distributed acoustic sensing (DAS).  In close cooperation with the municipal utilities, we interrogated a 21 km-long dark telecommunication fibre whose trajectory followed the seismic lines as close as possible.  This was accompanied by a network of 15 three-component geophones for further control and research.</p><p>In this contribution we present the data set, the approach for geo-referencing the fibre, and first results regarding DAS recording capabilities of vibroseismic signals in an urban environment.  Following the paradigm that the high density of telecommunication networks in urban areas may facilitate the exploration of the often insufficiently known local geology, we strive to further shed light on the possibilities of their employment for urban exploration.  In this respect we aim at tackling the question of the accuracy of fibre localization, recording sensitivity and range of active stimulation.</p>

Effective Safety Improvements Through Low-Cost Treatments

2000 ◽  
Vol 1734 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Tapan K. Datta ◽  
David Feber ◽  
Kerrie Schattler ◽  
Sue Datta
Keyword(s):  
Traffic Control ◽  
Urban Areas ◽  
Joint Venture ◽  
Low Cost ◽  
Evaluation Study ◽  
Traffic Crashes ◽  
Traffic Crash ◽  
Study Results ◽  
Before And After ◽  
The City

A vast majority of traffic crashes in urban areas occur at signalized intersections. Roadway geometry, traffic control, adjacent land uses, and environmental factors at intersections often contribute to the high incidence of traffic crashes and injuries. A public-private partnership project to identify high-crash and high-risk locations in the city of Detroit was initiated in 1996. Eighteen candidate sites were selected, and an extensive engineering study was conducted to develop countermeasures to help alleviate the traffic crash problem at the selected sites. The Automobile Association of America, Michigan, was the private partner in this joint venture and, in partnership with the city of Detroit, was a major contributor to covering the cost of improvements. The selection of countermeasures was based on state-of-the-art methodology and analysis, and implementation of the selected countermeasures at some of the sites was undertaken as the initial phase of the project. A comprehensive before-and-after evaluation study was performed at three of the improved sites. The study revealed that the safety improvements that were implemented lowered both crash and severity experience. The differences between the before and after crash frequencies proved to be statistically significant. Additionally, a benefit-cost analysis at the study locations indicated extraordinary results. This research presents the evaluation study results and discusses the countermeasures and improvements that were the most successful in mitigating traffic crash problems at the selected study locations.

scholarly journals DIY Urbanism: Influences & Impacts on Community Planning

Topophilia ◽  
2017 ◽  
pp. 67-71
Author(s):  
Steven Shuttle
Keyword(s):  
Community Engagement ◽  
Urban Areas ◽  
Public Safety ◽  
Low Cost ◽  
Community Planning ◽  
Small Scale ◽  
Community Members ◽  
Do It Yourself

‘Do It Yourself’ (DIY) urbanism is usually initiated by community members using a grassroots approach to change urban areas. Community planning involves making decisions about urban areas. This paper examines topics regarding DIY urbanism and community planning. Community engagement, neoliberalism and municipal support are key influences of DIY urbanism related to planning. DIY urbanism impacts the planner’s role as well as the relationships between planners, communities and municipalities. Three Canadian examples of DIY urbanism are introduced, including the Urban Repair Squad, PARK(ing) Day, and CITYlab. Discussion focuses on the opportunities and potential challenges of DIY urbanism for planners to consider. Potential challenges include public safety and municipal liability. Recommendations for planners regarding DIY urbanism are provided. DIY urbanism can be beneficial if planners work collaboratively and focus on small scale, low cost improvements.

scholarly journals Reducing post-harvest losses in fruits and vegetables for ensuring food security – Case of Sri Lanka

2021 ◽  
Vol 9 (1) ◽  
pp. 7-16
Author(s):  
Leelananda Rajapaksha ◽  
DMC Champathi Gunathilake ◽  
SM Pathirana ◽  
TN Fernando
Keyword(s):  
Food Security ◽  
Sri Lanka ◽  
Urban Areas ◽  
Low Cost ◽  
Economic Benefits ◽  
Fruit And Vegetables ◽  
Cold Chain ◽  
Small Scale ◽  
Post Harvest ◽  
Wide Range

In Sri Lanka, 70% of 21 million population live in non-urban areas, and agriculture provides livelihood for approximately 40% of them. The agricultural marketing process in the country is a complex operation due to services and functions involved in moving a crop product from where it was produced to where it would finally be consumed. Further, with a wide range of agricultural crops being produced, post-harvest handling process create different degrees of quantitative and qualitative losses in a complex market chain, which are estimated at 20% to 40% for vegetables and 30% - 40% for fruits. Improper and non-scientific post-harvest practices and handling, gaps in integration of cold chain practices & elements with post-harvest process, and lack of knowledge & awareness on many related aspects at grass root farmer level etc. appear to contribute to losses that finally prevent due economic benefits reaching the small-scale producer. In order to increase the effectiveness of post-harvest process handling of fruit and vegetables, appropriate corrective measures targeting small scale producers as well as commercial scale producers need to be popularized and practiced. At small scale producer level, promotion of appropriate low-cost post-harvest practices and procedures, facilitating low-cost cold chain elements and user-friendly information flow mechanism on market situation would certainly help avoid some of the steps that lead to losses. Monitoring system of commercial post-harvest handling process that ensure scientific bulk handling, storage and transportation of fruit and vegetables, properly designed economic centers with well regulated environmentcontrolled storages etc. would greatly reduce loses in bulk handling, ensuring better food security in the island.

scholarly journals High-resolution measurements from the airborne Atmospheric Nitrogen Dioxide Imager (ANDI)

2015 ◽  
Vol 8 (11) ◽  
pp. 4735-4754 ◽  
Author(s):  
J. P. Lawrence ◽  
J. S. Anand ◽  
J. D. Vande Hey ◽  
J. White ◽  
R. R. Leigh ◽  
...  
Keyword(s):  
Nitrogen Dioxide ◽  
Column Density ◽  
Road Traffic ◽  
City Centre ◽  
Background Concentration ◽  
Atmospheric Nitrogen ◽  
Vertical Column ◽  
East Midlands ◽  
Test Flight ◽  
The City

Abstract. Nitrogen dioxide is both a primary pollutant with direct health effects and a key precursor of the secondary pollutant ozone. This paper reports on the development, characterisation and test flight of the Atmospheric Nitrogen Dioxide Imager (ANDI) remote sensing system. The ANDI system includes an imaging UV/Vis grating spectrometer able to capture scattered sunlight spectra for the determination of tropospheric nitrogen dioxide (NO2) concentrations by way of DOAS slant column density and vertical column density measurements. Results are shown for an ANDI test flight over Leicester City in the UK on a cloud-free winter day in February 2013. Retrieved NO2 columns gridded to a surface resolution of 80 m × 20 m revealed hotspots in a series of locations around Leicester City, including road junctions, the train station, major car parks, areas of heavy industry, a nearby airport (East Midlands) and a power station (Ratcliffe-on-Soar). In the city centre the dominant source of NO2 emissions was identified as road traffic, contributing to a background concentration as well as producing localised hotspots. Quantitative analysis revealed a significant urban increment over the city centre which increased throughout the flight.

scholarly journals The Eulerian urban dispersion model EPISODE. Part II: Extensions to the source dispersion and photochemistry for EPISODE-CityChem v1.2 and its application to the city of Hamburg

2019 ◽  
Author(s):  
Matthias Karl ◽  
Sam-Erik Walker ◽  
Sverre Solberg ◽  
Martin O. P. Ramacher
Keyword(s):  
Air Quality ◽  
Atmospheric Chemistry ◽  
Urban Areas ◽  
Dispersion Model ◽  
Model Performance ◽  
Pollutant Dispersion ◽  
Lower Latitude ◽  
Urban Dispersion ◽  
Grid Model ◽  
The City

Abstract. This paper describes the CityChem extension of the Eulerian urban dispersion model EPISODE. The development of the CityChem extension was driven by the need to apply the model in lower latitude cities with higher insolation than in northern European cities. The CityChem extension offers a more advanced treatment of the photochemistry in urban areas and entails specific developments within the sub-grid components for a more accurate representation of the dispersion in the proximity of urban emission sources. The WMPP (WORM Meteorological Pre-Processor) is used in the point source sub-grid model to calculate the wind speed at plume height. The simplified street canyon model (SSCM) is used in the line source sub-grid model to calculate pollutant dispersion in street canyons. The EPISODE-CityChem model integrates the CityChem extension in EPISODE, with the capability of simulating photochemistry and dispersion of multiple reactive pollutants within urban areas. The main focus of the model is the simulation of the complex atmospheric chemistry involved in the photochemical production of ozone in urban areas. EPISODE-CityChem was evaluated with a series of tests and with a first application to the air quality situation in the city of Hamburg, Germany. A performance analysis with the FAIRMODE DELTA Tool for the air quality in Hamburg showed that the model fulfils the model performance objectives for NO2 (hourly), O3 (daily max. of the 8-h running mean) and PM10 (daily mean) set forth in the Air Quality Directive, qualifying the model for use in policy applications. Observed levels of annual mean ozone at the five urban background stations in Hamburg are captured by the model within 15 %. Envisaged applications of the EPISODE-CityChem model are urban air quality studies, emission control scenarios in relation to traffic restrictions and the source attribution of sector-specific emissions to observed levels of air pollutants at urban monitoring stations.

scholarly journals LIFE MONZA: project description and actions’ updating

Noise Mapping ◽  
2018 ◽  
Vol 5 (1) ◽  
pp. 60-70 ◽  
Author(s):  
Chiara Bartalucci ◽  
Francesco Borchi ◽  
Monica Carfagni ◽  
Rocco Furferi ◽  
Lapo Governi ◽  
...  
Keyword(s):  
Air Quality ◽  
Urban Areas ◽  
Air Pollutants ◽  
Road Traffic ◽  
Ambient Air ◽  
Limit Values ◽  
Low Emission ◽  
Project Description ◽  
Air Quality Improvement ◽  
The City

Abstract The introduction of Low Emission Zones, urban areas subject to road traffic restrictions in order to ensure compliance with the air pollutants limit values set by the European Directive on ambient air quality (2008/50/EC), is a common and well-established action in the administrative government of cities. The impacts on air quality improvement are widely analysed, whereas the effects and benefits concerning the noise have not been addressed in a comprehensive manner. As a consequence, the definition, the criteria for the analysis and the management methods of a Noise Low Emission Zone are not clearly expressed and shared yet. The LIFE MONZA project (Methodologies fOr Noise low emission Zones introduction And management - LIFE15 ENV/IT/000586) addresses these issues. The first objective of the project, co-funded by the European Commission, is to introduce an easy-replicable method for the identification and the management of the Noise Low Emission Zone, an urban area subject to traffic restrictions, whose impacts and benefits regarding noise issues will be analyzed and tested in the pilot area of the city of Monza, located in Northern Italy. Background conditions, structure, objectives of the project and actions’ progress will be discussed in this article.

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