scholarly journals Spatial and Annual Temporal Distribution of Ozone Concentrations in the Madrid Basin Using Passive Samplers

2001 ◽  
Vol 1 ◽  
pp. 785-795 ◽  
Author(s):  
M.J. Sanz ◽  
F. Sanz ◽  
G. Sanchez-Peaa
Keyword(s):  
Complex Terrain ◽  
Continuous Monitoring ◽  
Temporal Distribution ◽  
Early Spring ◽  
Passive Samplers ◽  
Ozone Concentrations ◽  
Ozone Distribution ◽  
Forested Areas ◽  
The City ◽  
Ozone Levels

Passive samplers are useful tools for helping to describe the ozone distribution in complex terrain situations. They are also a good complement to continuous monitoring stations. This paper discusses the results of a pilot study that used ozone passive samplers to describe the spatial and annual temporal distribution of ozone in several forested areas around the city of Madrid. The ozone concentrations around Madrid were found to be higher on the elevated sites located at a certain distance from the city�s urban zone. A seasonal ozone cycle was observed, with maximum concentrations found in the basin in late spring or summer depending on the location. The information obtained allowed us to group the locations into four classes. Altitude and distance to the city during the summer and winter explained the observed ozone concentrations. However, during the transition periods, especially in early spring and to a lesser extent in autumn, there was not a good correlation between ozone levels and elevation or distance from precursor sources. These data strongly suggest that altitudinal gradients for ozone are not always the case in the Madrid Basin.

scholarly journals Vertical Distribution of Ozone and Nitrogenous Pollutants in an Air Quality Class I Area, the San Gorgonio Wilderness, Southern California

2002 ◽  
Vol 2 ◽  
pp. 10-26 ◽  
Author(s):  
Rocio Alonso ◽  
Andrzej Bytnerowicz ◽  
Michael Arbaugh
Keyword(s):  
Nitric Acid ◽  
Air Pollutants ◽  
Elevation Gradient ◽  
Temporal Distribution ◽  
Air Pollutant ◽  
Passive Samplers ◽  
Class I ◽  
San Bernardino Mountains ◽  
Ozone Concentrations ◽  
Wilderness Area

Information about spatial and temporal distribution of air pollutants is essential for better understanding of environmental stresses affecting forests and estimation of potential risks associated with air pollutants. Ozone and nitrogenous air pollutants were monitored along an elevation gradient in the Class I San Gorgonio Wilderness area (San Bernardino Mountains, California, U.S.) during the summer of 2000 (mid-June to mid-October). Passive samplers were exposed for 2-week periods at six sampling sites located at 300 m intervals ranging from 1200 to 2700 m elevation. Elevated concentrations of ozone were found in this area with summer 24-h hourly means ranging from 53 to 59 ppb. The highest ozone concentrations were detected in the period July 25 to August 8, reaching values of 64 to 72 ppb expressed as 2-week mean. Passive-sampler ozone data did not show a clear relationship with elevation, although during the periods with higher ozone levels, ozone concentrations were higher at those sites below 2000 m than at sites located above that elevation. All nitrogenous pollutants studied showed a consistent decrease of concentrations with elevation. Nitrogen dioxide (NO2) levels were low, decreasing with increasing elevation from 6.4 to 1.5 ppb summer means. Nitric oxide (NO) concentrations were around 1 to 2 ppb, which is within the range of the detection levels of the devices used. Nitric acid (HNO3) vapor concentrations were lower at higher elevations (summer means 1.9 to 2.5 μg m-3) than at lower elevations (summer means 4.3 to 5.1 μg m-3). Summer concentrations of ammonia (NH3) were slightly higher than nitric acid ranging from 6 μg m-3at the lowest site to 2.5 μg m-3registered at the highest elevation. Since complex interactions between ozone and nitrogenous air pollutants have already been described for forests, simultaneous information about the distribution of these pollutants is needed. This is particularly important in mountain terrain where no reliable models of air pollutant distribution exist.

scholarly journals An overview of mosquitoes and emerging arboviral infections in the Zagreb area, Croatia

2016 ◽  
Vol 10 (12) ◽  
pp. 1286-1293 ◽  
Author(s):  
Ana Klobucar ◽  
Nikola Benic ◽  
Darko Krajcar ◽  
Mirjana Lana Kosanovic-Licina ◽  
Vanja Tesic ◽  
...  
Keyword(s):  
Culex Pipiens ◽  
Mosquito Control ◽  
Mosquito Species ◽  
Early Spring ◽  
Breeding Sites ◽  
Human West Nile Virus ◽  
Recent Emergence ◽  
Forested Areas ◽  
Zagreb Area ◽  
The City

Mosquito control in the Zagreb area has been conducted for many years, whereas the fauna has only been investigated in the last 20 years. So far 30 mosquito species have been detected in the city area. Culex pipiens form molestus is the dominant mosquito species in indoor breeding sites. In forested areas and areas exposed to flooding, the active period is early spring and the dominant species are Ochlerotatus sticticus, Ochlerotatus cantans, Ochlerotatus geniculatus and Aedes vexans. The eudominant mosquito species found in the artificial breeding sites are Culex pipiens and the Asian tiger mosquito, Aedes albopictus. Invasive Ae. albopictus, present in the Zagreb area since 2004, has expanded to a larger area of the city during the last three years. The recent emergence of the human West Nile virus and Usutu virus neuroinvasive disease in Zagreb and its surroundings highlighted the role of mosquitoes as vectors of emerging arboviruses. The paper focuses on mosquito species and arboviral infections detected in humans and animals in the Zagreb area, Croatia.

Considerations on Ambient Levels of Ozone Concentrations and Relationship with NOx in an Urban Environment

2017 ◽  
Vol 68 (4) ◽  
pp. 824-829
Author(s):  
Cornel Ianache ◽  
Laurentiu Predescu ◽  
Mirela Predescu ◽  
Dumitru Dumitru
Keyword(s):  
Nitrogen Oxides ◽  
Urban Areas ◽  
Road Traffic ◽  
Temporal Distribution ◽  
Ground Level ◽  
Distinct Pattern ◽  
Weekend Effect ◽  
Monitoring Site ◽  
Ground Level Ozone ◽  
Ozone Concentrations

The serious air pollution problem has determined public concerns, worldwide. One of the main challenges for countries all over the world is caused by the elevated levels of ground-level ozone (O3) concentrations and its anthropogenic precursors. Ploiesti city, as one of the major urban area of Romania, is facing the same situation. This research aims to investigate spatial and temporal distribution characteristics of O3 in relationship with nitrogen oxides (NOx) using statistical analysis methods. Hourly O3 and NOx measurements were collected during 2014 year in Ploiesti. The results obtained showed that the ozone spatial distribution was non-normal for each month in 2014. The diurnal cycle of ground-level ozone concentrations showed a mid-day peak, while NOx diurnal variations presented 2 daily peaks, one in the morning (7:00 a.m.) and one in the afternoon (between 5:00 and 7:00 p.m.). In addition, it was observed a distinct pattern of weekly variations for O3 and NOx. Like in many other urban areas, the results indicated the presence of the �ozone weekend effect� in Ploiesti during the 2014 year, ozone concentrations being slightly higher on weekends compared to weekdays. For the same monitoring site, the nitrogen oxides were less prevalent on Saturdays and Sundays, probably due to reducing of road traffic and other pollution-generating activities on weekends than during the week.

scholarly journals Spatial–Temporal Distribution Variation of Ground-Level Ozone in China’s Pearl River Delta Metropolitan Region

2021 ◽  
Vol 18 (3) ◽  
pp. 872
Author(s):  
An Zhang ◽  
Jinhuang Lin ◽  
Wenhui Chen ◽  
Mingshui Lin ◽  
Chengcheng Lei
Keyword(s):  
Ozone Concentration ◽  
Pearl River Delta ◽  
Temporal Distribution ◽  
Ground Level ◽  
Metropolitan Region ◽  
Pearl River ◽  
Ozone Pollution ◽  
Ground Level Ozone ◽  
Ozone Concentrations ◽  
The North

Long-term exposure to ozone pollution will cause severe threats to residents’ physical and mental health. Ground-level ozone is the most severe air pollutant in China’s Pearl River Delta Metropolitan Region (PRD). It is of great significance to accurately reveal the spatial–temporal distribution characteristics of ozone pollution exposure patterns. We used the daily maximum 8-h ozone concentration data from PRD’s 55 air quality monitoring stations in 2015 as input data. We used six models of STK and ordinary kriging (OK) for the simulation of ozone concentration. Then we chose a better ozone pollution prediction model to reveal the ozone exposure characteristics of the PRD in 2015. The results show that the Bilonick model (BM) model had the highest simulation precision for ozone in the six models for spatial–temporal kriging (STK) interpolation, and the STK model’s simulation prediction results are significantly better than the OK model. The annual average ozone concentrations in the PRD during 2015 showed a high spatial variation in the north and east and low in the south and west. Ozone concentrations were relatively high in summer and autumn and low in winter and spring. The center of gravity of ozone concentrations tended to migrate to the north and west before moving to the south and then finally migrating to the east. The ozone’s spatial autocorrelation was significant and showed a significant positive correlation, mainly showing high-high clustering and low-low clustering. The type of clustering undergoes temporal migration and conversion over the four seasons, with spatial autocorrelation during winter the most significant.

scholarly journals Abundance and spatial-temporal distribution of Macrobrachium surinamicum Holthuis, 1948 (Palaemonidae) in the Amazon estuary, north of Brazil

2016 ◽  
Vol 77 (3) ◽  
pp. 594-601
Author(s):  
D. V. Cavalcante ◽  
B. S. Bentes ◽  
J. M. Martinelli-Lemos
Keyword(s):  
Significant Influence ◽  
Abiotic Factors ◽  
Temporal Distribution ◽  
Artisanal Fisheries ◽  
Spatial And Temporal Distribution ◽  
Low Salinity ◽  
Amazon Estuary ◽  
Disturbed Areas ◽  
Macrobrachium Amazonicum ◽  
The City

Abstract Macrobrachium surinamicum is a small shrimp that inhabits rivers of low salinity. It is mainly caught as bycatch in Amazon shrimp Macrobrachium amazonicum fisheries, which is widely exploited by artisanal fisheries for food and economic needs of the riverside population. This study aimed to characterize the spatial and temporal distribution of the freshwater shrimp M. surinamicum in the Guajará Bay and on Mosqueiro Island, correlating the abundance of this species with abiotic factors (temperature and salinity). Samples were taken from May 2006 to April 2007 in six locations: Mosqueiro Island (Furo das Marinhas and Porto do Pelé); Icoaraci district; Arapiranga Island, edge of the city of Belém; and Combu Island, using traps named 'matapis'. A total of 361 shrimps were caught. The abundance was higher in December and lower in July 2006. The biggest catch occurred on Arapiranga Island and the lowest on Mosqueiro Island. The abundance differed significantly in December 2006 and no variable studied had significant influence on M. surinamicum abundance. In Guajará Bay, particularly the more sheltered places, as Arapiranga and Combu islands, favor the development of M. surinamicum, indicating that this species has preference for less disturbed areas.

scholarly journals Head for the Hills

2021 ◽  
Author(s):  
◽  
William Briscoe
Keyword(s):  
Complex Terrain ◽  
Visual Programming ◽  
City Council ◽  
Proof Of Concept ◽  
Generative Design ◽  
Urban Theory ◽  
Urban Networks ◽  
Difficult Terrain ◽  
Visual Programming Language ◽  
The City

<p><b>In the context of urban design, generative design has been examined as a tool for expansion or optimisation of existing urban networks. This optimisation uses information such as geometry of the existing urban fabric and available space for expansion. However, very little research exists into designing around terrain factors, instead usually opting to consider difficult terrain as simply a boundary for network expansion. </b></p> <p>This research seeks to answer the question ‘How can generative design improve the way urban networks are designed in complex terrain?’ It does this by creating a tool that can interpret any terrain information, and with simple designer input, can create conceptual urban schemes in complex terrain. </p> <p>The tool is developed using visual programming language Grasshopper, an extension for the Rhinoceros3D modelling software. Its development and proof-of-concept scheme are executed in Wellington, New Zealand. The city is one uniquely situated between harbour and steep hills, leading to several typologies of hillside urban schemes to use as precedent and comparison with the tool’s outputs. The Wellington City Council Urban Growth Plan anticipates an increase of 80,000 people in the next 30 years, and the city requires additional areas to house the growing population. </p> <p>Through a discussion of urban theory and existing generative design exemplars, the thesis settles on an urban grid-based logic for the tool. The thesis then records the process of designing the tool, using a Wellington site as a base for development. </p> <p>Evaluation of the tool is undertaken using space syntax theory as a key framework, as well as qualitative comparisons with existing hill suburbs in Wellington.</p>

scholarly journals ACADEMICIAN ALEKSANDR FYODOROVICH TUR (ON THE 125TH ANNIVERSARY OF THE BIRTH OF THE TEACHER)

2019 ◽  
Vol 21 (4) ◽  
pp. 249-254
Author(s):  
N. P. Shabalov ◽  
L. V. Erman ◽  
M. V. Erman
Keyword(s):  
Continuous Monitoring ◽  
Pediatric Endocrinology ◽  
Medical Sciences ◽  
75Th Anniversary ◽  
Pediatric Hematology ◽  
Children's Nutrition ◽  
Great Patriotic War ◽  
125Th Anniversary ◽  
The City ◽  
Lenin Prize

The article is dedicated to the 125th anniversary of the birth of the outstanding Russian pediatrician, Academician Aleksandr Fyodorovich Tur and the 75th anniversary of the lifting the siege of Leningrad in the Great Patriotic War. Professor A.F. Tur directly participated in the organization of medical care for children in the besieged city of Leningrad, for 10 years he was the chief pediatrician of the city. The experience of the work of children’s polyclinics in Leningrad on the basis of a single pediatrician subsequently became the property of the whole country. A.F. Tur made a huge contribution to the protection of children of the besieged city, directed the Children’s Nutrition Board, proposed original methods for combating alimentary dystrophy, helped to create a system of rigorous provision of children with food, shelter, fuel, organization of the correct regime in shelters, and continuous monitoring of vaccinations for children. The Society of Pediatric Doctors headed by Prof. Yu.A. Mendeleva and A.F. Tur was one of the first to renew its meetings in the besieged Leningrad. The name of A.F. Tur is associated with the establishment of domestic dietetics, neonatology, pediatric hematology, pediatric endocrinology. Among his students, there are more than 110 candidates and 28 doctors of medical sciences. In peacetime, A.F. Tur was awarded two orders of Lenin, in 1970 he was awarded (jointly with G.N. Speranskii and Yu.F. Dombrovskaya) the title of the Laureate of the Lenin Prize “... for a series of works on the physiology and pathology of young children, contributing to a sharp decline in morbidity and mortality among them».

scholarly journals The impacts of precursor reduction and meteorology on ground-level ozone in the Greater Toronto Area

2014 ◽  
Vol 14 (15) ◽  
pp. 8197-8207 ◽  
Author(s):  
S. C. Pugliese ◽  
J. G. Murphy ◽  
J. A. Geddes ◽  
J. M. Wang
Keyword(s):  
Health Hazard ◽  
Ground Level ◽  
Ozone Production ◽  
Ground Level Ozone ◽  
Ozone Concentrations ◽  
Greater Toronto Area ◽  
High Solar Radiation ◽  
Linear Effects ◽  
Human Health Hazard ◽  
Ozone Levels

Abstract. Tropospheric ozone (O3) is a major component of photochemical smog and is a known human health hazard, as well as a damaging factor for vegetation. Its precursor compounds, nitrogen oxides (NOx) and volatile organic compounds (VOCs), have a variety of anthropogenic and biogenic sources and exhibit non-linear effects on ozone production. As an update to previous studies on ground-level ozone in the Greater Toronto Area (GTA), we present an analysis of NO2, VOC and O3 data from federal and provincial governmental monitoring sites in the GTA from 2000 to 2012. We show that, over the study period, summertime 24 h VOC reactivity and NO2 midday (11:00–15:00) concentrations at all sites decreased significantly; since 2000, all sites experienced a decrease in NO2 of 28–62% and in measured VOC reactivity of at least 53–71%. Comparing 2002–2003 to 2011–2012, the summed reactivity of OH towards NO2 and a suite of measured VOCs decreased from 8.6 to 4.6 s−1. Ratios of reactive VOC pairs indicate that the effective OH concentration experienced by primary pollutants in the GTA has increased significantly over the study period. Despite the continuous decrease in precursor levels, ozone concentrations are not following the same pattern at all stations; it was found that the Canada-wide Standard for ozone continues to be exceeded at all monitoring stations. Additionally, while the years 2008–2011 had consistently lower ozone levels than previous years, 2012 experienced one of the highest recorded summertime ozone concentrations and a large number of smog episodes. We demonstrate that these high ozone observations in 2012 may be a result of the number of days with high solar radiation, the number of stagnant periods and the transport of high ozone levels from upwind regions.

Simulation of the Cooking Organic Aerosol Concentration Variability in an Urban Area

2021 ◽  
Author(s):  
Evangelia Siouti ◽  
Ksakousti Skyllakou ◽  
Ioannis Kioutsioukis ◽  
Giancarlo Ciarelli ◽  
Spyros N. Pandis
Keyword(s):  
Urban Area ◽  
Urban Areas ◽  
Temporal Distribution ◽  
Late Summer ◽  
Field Studies ◽  
Organic Aerosol ◽  
Basis Set ◽  
Cooking Times ◽  
The City ◽  
Lunch Time

&lt;p&gt;Cooking operations can be an important fine PM source for urban areas. Cooking emissions are a source of pollution that has been often ignored and are not included or are seriously underestimated in urban emission inventories. However, several field studies in cities all over Europe suggest that cooking organic aerosol (COA) can be an important component of the total organic PM. In this study we propose and evaluate a methodology for the simulation of the COA concentration and its variability in space and time in an urban area. The city of Patras, the third biggest in Greece is used for this first application for a typical late summer period. The spatial distribution of COA emissions is based on the exact location of restaurants and grills, while the emissions on the meat consumption in Greece. We estimated COA emissions of 150 kg d&lt;sup&gt;-1&lt;/sup&gt; that corresponds to 0.6 g d&lt;sup&gt;-1&lt;/sup&gt; per person. The temporal distribution of COA was based on the known cooking times and the results of the past field studies in the area. Half of the daily COA is emitted during dinner time (21:00-0:00 LT), while approximately 25% during lunch time (13:00-16:00 LT). The COA is simulated using the Volatility Basis Set with a volatility distribution measured in the laboratory and is treated as semivolatile and reactive. The maximum average COA concentration during the simulation period is predicted to be 1.3 &amp;#956;g m&lt;sup&gt;-3&lt;/sup&gt; in a mainly pedestrian area with a high density of restaurants. Peak hourly COA concentrations in this area exceed 10 &amp;#956;g m&lt;sup&gt;-3&lt;/sup&gt; during several nights. The local production of secondary COA is predicted to be slow and it represents just a few percent of the total COA.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;

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