scholarly journals The use of tunnel concentration profile data to determine the ratio of NO<sub>2</sub>/NO<sub>x</sub> directly emitted from vehicles

2005 ◽  
Vol 5 (6) ◽  
pp. 12723-12740 ◽  
Author(s):  
X. Yao ◽  
N. T. Lau ◽  
C. K. Chan ◽  
M. Fang
Keyword(s):  
Air Quality ◽  
Urban Areas ◽  
Air Pollutants ◽  
Quality Data ◽  
Concentration Profiles ◽  
Profile Data ◽  
Annual Average ◽  
Air Quality Data ◽  
Monitoring Platform

Abstract. Recently, it is reported that primary vehicular NO2/NOx ratio to be 10–30% and primary vehicular NO2 has raised much interest and concern in the control of NO2 in urban areas. In this study, primary vehicular NO2/NOx ratio in Hong Kong was investigated based on intensive long tunnel (3.7–4 km in length) experiments where concentration profiles of air pollutants along the entire lengths of the tunnels were obtained. Long tunnels were selected because of the inherent low O3 concentrations in the partially enclosed environment. In addition the concentrations of pollutants from vehicles are high. Thus, the NO2 measured inside long tunnels would be more representative of the primary NO2 emitted by vehicles and contribution due to atmospheric transformation would be limited. This dataset was supported by a long-term on-road air quality dataset (June 2002–August 2003). Both datasets were obtained using the Mobile Real-time Air Monitoring Platform (MAP). The primary on-road vehicular NO2/NOx ratio was less than 2%, detected in the mid sections of tunnels investigated, where O3 concentration was at a minimum. In sections of the tunnels (entrance and exit) where O3 concentrations were relatively high, the NO2/NOx ratio could be as high as 19%. Long-term (annual average) on-road air quality data in open air yielded NO2/NOx ratios up to 28%. Thus, it is apparent that directly emitted NO2 from vehicles is not significant in atmospheric NO2 concentration. A simple model was used to segregate the contribution of background NO2 and transformed NO2 measured in vehicle plumes.

Temporal patterns and trends of surface ozone concentrations over Portugal

2021 ◽  
Author(s):  
Carla Gama ◽  
Alexandra Monteiro ◽  
Myriam Lopes ◽  
Ana Isabel Miranda
Keyword(s):  
Air Quality ◽  
Iberian Peninsula ◽  
Human Health ◽  
Temporal Variability ◽  
Urban Areas ◽  
Surface Ozone ◽  
Quality Data ◽  
Ozone Concentrations ◽  
Long Term Study

&lt;p&gt;Tropospheric ozone (O&lt;sub&gt;3&lt;/sub&gt;) is a critical pollutant over the Mediterranean countries, including Portugal, due to systematic exceedances to the thresholds for the protection of human health. Due to the location of Portugal, on the Atlantic coast at the south-west point of Europe, the observed O&lt;sub&gt;3&lt;/sub&gt; concentrations are very much influenced not only by local and regional production but also by northern mid-latitudes background concentrations. Ozone trends in the Iberian Peninsula were previously analysed by Monteiro et al. (2012), based on 10-years of O&lt;sub&gt;3&lt;/sub&gt; observations. Nevertheless, only two of the eleven background monitoring stations analysed in that study are located in Portugal and these two stations are located in Porto and Lisbon urban areas. Although during pollution events O&lt;sub&gt;3&lt;/sub&gt; levels in urban areas may be high enough to affect human health, the highest concentrations are found in rural locations downwind from the urban and industrialized areas, rather than in cities. This happens because close to the sources (e.g., in urban areas) freshly emitted NO locally scavenges O&lt;sub&gt;3&lt;/sub&gt;. A long-term study of the spatial and temporal variability and trends of the ozone concentrations over Portugal is missing, aiming to answer the following questions:&lt;/p&gt;&lt;p&gt;-&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; What is the temporal variability of ozone concentrations?&lt;/p&gt;&lt;p&gt;-&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; Which trends can we find in observations?&lt;/p&gt;&lt;p&gt;-&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; How were the ozone spring maxima concentrations affected by the COVID-19 lockdown during spring 2020?&lt;/p&gt;&lt;p&gt;In this presentation, these questions will be answered based on the statistical analysis of O&lt;sub&gt;3&lt;/sub&gt; concentrations recorded within the national air quality monitoring network between 2005 and 2020 (16 years). The variability of the surface ozone concentrations over Portugal, on the timescales from diurnal to annual, will be presented and discussed, taking into account the physical and chemical processes that control that variability. Using the TheilSen function from the OpenAir package for R (Carslaw and Ropkins 2012), which quantifies monotonic trends and calculates the associated p-value through bootstrap simulations, O&lt;sub&gt;3&lt;/sub&gt; concentration long-term trends will be estimated for the different regions and environments (e.g., rural, urban).&amp;#160; Moreover, taking advantage of the unique situation provided by the COVID-19 lockdown during spring 2020, when the government imposed mandatory confinement and citizens movement restriction, leading to a reduction in traffic-related atmospheric emissions, the role of these emissions on ozone levels during the spring period will be studied and presented.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;Carslaw and Ropkins, 2012. Openair&amp;#8212;an R package for air quality data analysis. Environ. Model. Softw. 27-28,52-61. https://doi.org/10.1016/j.envsoft.2011.09.008&lt;/p&gt;&lt;p&gt;Monteiro et al., 2012. Trends in ozone concentrations in the Iberian Peninsula by quantile regression and clustering. Atmos. Environ. 56, 184-193. https://doi.org/10.1016/j.atmosenv.2012.03.069&lt;/p&gt;

scholarly journals NanoSen-AQM: From Sensors to Users

2020 ◽  
Vol 16 (04) ◽  
pp. 51
Author(s):  
Pedro Lucas ◽  
Jorge Silva ◽  
Filipe Araujo ◽  
Catarina Silva ◽  
Paulo Gil ◽  
...  
Keyword(s):  
Air Quality ◽  
Low Cost ◽  
Sensor Data ◽  
Quality Data ◽  
Easy Access ◽  
The Public ◽  
Nano Sensors ◽  
The Cost ◽  
Air Quality Data ◽  
Monitoring Platform

With the raising of environmental concerns regarding pollution, interest in monitoring air quality is increasing. However, air pollution data is mostly originated from a limited number of government-owned sensors, which can only capture a small fraction of reality. Improving air quality coverage in-volves reducing the cost of sensors and making data widely available to the public. To this end, the NanoSen-AQM project proposes the usage of low-cost nano-sensors as the basis for an air quality monitoring platform, capa-ble of collecting, aggregating, processing, storing, and displaying air quality data. Being an end-to-end system, the platform allows sensor owners to manage their sensors, as well as define calibration functions, that can im-prove data reliability. The public can visualize sensor data in a map, define specific clusters (groups of sensors) as favorites and set alerts in the event of bad air quality in certain sensors. The NanoSen-AQM platform provides easy access to air quality data, with the aim of improving public health.

Street level air quality data collected by the Mobile Real-time Air Monitoring Platform (MAP)

2015 ◽  
Author(s):  
Ming Fang ◽  
Xiaohong Yao ◽  
Chak-Keung Chan ◽  
Ngai Ting Lau ◽  
Arthur P. S Lau
Keyword(s):  
Air Quality ◽  
Real Time ◽  
Air Monitoring ◽  
Quality Data ◽  
Street Level ◽  
Air Quality Data ◽  
Monitoring Platform

scholarly journals Mapping pediatric A&E respiratory presentations with air quality

2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Dermot Glackin
Keyword(s):  
Public Health ◽  
Emergency Department ◽  
Air Quality ◽  
Air Pollutants ◽  
Causal Link ◽  
Quality Monitoring ◽  
Quality Data ◽  
Air Quality Monitoring ◽  
Respiratory Condition ◽  
Air Quality Data

IntroductionWest Belfast Partnership Board undertook a collaborative public health investigation to explore what if any correlation exists between air quality and children from the Falls Divis area presenting to RBHSC with a respiratory condition. BackgroundAn analysis of Emergency Department Attendances showed monthly trend in 2015/16 differed from previous years with a peak in November 2015 which was 27% higher than the number of attendances in November of 2014. The overall increase in 2015/16 across the 4 main paediatric categories was 10%. The increase for respiratory was 34% higher. West Belfast accounted for 32% (248n) of this spike. There exists a compelling case for linkage between air quality and a range of conditions which is socially patterned. Falls and Divis area appears in the top 3 areas of multiple deprivation. ApproachWe identified periods of elevated paediatric presentation at A&E with repository compliant and mapped over air quality monitoring data from the same period in the Falls Divis area; Factoring potential incubation time between exposure to potential harmful air pollutants. ConclusionBased upon a review of air quality data no causal link was established between air quality and periods of elevated presentation of children at A&E with respiratory evident.

scholarly journals COVID-19 and the Improvement of the Global Air Quality: The Bright Side of a Pandemic

Atmosphere ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1279
Author(s):  
Hamideh Habibi ◽  
Ripendra Awal ◽  
Ali Fares ◽  
Masoud Ghahremannejad
Keyword(s):  
Air Quality ◽  
Air Pollutants ◽  
Nitrogen Monoxide ◽  
Weather Conditions ◽  
Quality Data ◽  
Global Response ◽  
The Past ◽  
Air Quality Improvement ◽  
Bright Side ◽  
Air Quality Data

The objective of this investigation is to study the impacts of the global response to COVID-19 on air pollution and air quality changes in major cities across the globe over the past few months. Air quality data (NO2, CO, PM2.5, and O3) were downloaded from the World Air Quality Index project for the January 2019–April 2020 period. Results show a significant reduction in the levels of 2020 NO2, CO, and PM2.5 compared to their levels in 2019. These reductions were as high as 63% (Wuhan, China), 61% (Lima, Peru), and 61% (Berlin, Germany), in NO2, CO, and PM2.5 levels, respectively. In contrast, 2020 O3 levels increased substantially, as high as 86% (Milan, Italy), in an apparent response to the decrease in titration by nitrogen monoxide and its derivatives. Significant differences in the weather conditions across the globe do not seem to impact this air quality improvement trend. Will this trend in the reduction in most air pollutants to unprecedented levels continue in the next few weeks or even months? The response to this and other questions will depend on the future global economic and environmental policies.

scholarly journals Impacts of the COVID-19 lockdown on air quality and its association with human mortality trends in megapolis Mexico City

2020 ◽  
Author(s):  
Gurusamy Kutralam-Muniasamy ◽  
Fermín Pérez-Guevara ◽  
Priyadarsi D. Roy ◽  
I. Elizalde-Martínez ◽  
V.C. Shruti
Keyword(s):  
Air Pollution ◽  
Latin America ◽  
Air Quality ◽  
Mexico City ◽  
Air Pollutants ◽  
Mortality Rates ◽  
Quality Data ◽  
Mortality Trends ◽  
Human Mortality ◽  
Air Quality Data

Abstract Mexico City is the second most populated city in Latin America, and it went through two partial lockdowns between April 1 and May 31, 2020 for reducing the COVID-19 propagation. The present study assessed air quality and its association with human mortality rates during the lockdown by estimating changes observed in air pollutants (CO, NO2, O3, SO2, PM10 and PM2.5) between the lockdown (April 1 - May 31) and pre-lockdown (January 1 – March 31) periods, as well as by comparing the air quality data of lockdown period with the same interval of previous five-years (2015-2019). Concentrations of NO2 (-29%), SO2 (-55%) and PM10 (-11%) declined and the contents of CO (+1.1%), PM2.5 (+19%) and O3 (+63%) increased during the lockdown compared to the pre-lockdown period. This study also estimated that NO2, SO2, CO, PM10 and PM2.5 reduced by 19-36%, and O3 enhanced by 14% compared to the average of 2015-2019. Reduction in traffic as well as less emission from vehicle exhausts led to remarkable decline in NO2, SO2 and PM10. The significant positive associations of PM2.5, CO and O3 with the numbers of COVID-19 infections and deaths, however, underscored the necessity to enforce air pollution regulations to protect human health in one of the important cities of the northern hemisphere.

scholarly journals The Diamond League athletic series: does the air quality sparkle?

2021 ◽  
Author(s):  
James R. Hodgson ◽  
Lee Chapman ◽  
Francis D. Pope
Keyword(s):  
Particulate Matter ◽  
Air Quality ◽  
Performance Metrics ◽  
Urban Air Pollution ◽  
Quality Data ◽  
Performance Variation ◽  
Short And Long Term ◽  
Respiratory Conditions ◽  
Race Performance

AbstractUrban air pollution can have negative short- and long-term impacts on health, including cardiovascular, neurological, immune system and developmental damage. The irritant qualities of pollutants such as ozone (O3), nitrogen dioxide (NO2) and particulate matter (PM) can cause respiratory and cardiovascular distress, which can be heightened during physical activity and particularly so for those with respiratory conditions such as asthma. Previously, research has only examined marathon run outcomes or running under laboratory settings. This study focuses on elite 5-km athletes performing in international events at nine locations. Local meteorological and air quality data are used in conjunction with race performance metrics from the Diamond League Athletics series to determine the extent to which elite competitors are influenced during maximal sustained efforts in real-world conditions. The findings from this study suggest that local meteorological variables (temperature, wind speed and relative humidity) and air quality (ozone and particulate matter) have an impact on athletic performance. Variation between finishing times at different race locations can also be explained by the local meteorology and air quality conditions seen during races.

Sign in / Sign up

Export Citation Format

Share Document