scholarly journals Assessment of urban aerosol pollution over the Moscow megacity by the MAIAC aerosol product

2020 ◽  
Vol 13 (2) ◽  
pp. 877-891
Author(s):  
Ekaterina Y. Zhdanova ◽  
Natalia Y. Chubarova ◽  
Alexei I. Lyapustin
Keyword(s):  
Agricultural Development ◽  
Moscow Region ◽  
Pollutant Emissions ◽  
City Centre ◽  
Construction Sites ◽  
Aerosol Pollution ◽  
Aerosol Sources ◽  
The Mean ◽  
The Difference ◽  
The City

Abstract. We estimated the distribution of aerosol optical thickness (AOT) with a spatial resolution of 1 km over the Moscow megacity using the MAIAC aerosol product based on MODIS satellite data (Lyapustin et al., 2018) for the warm period of the year (May–September, 2001–2017). AERONET (Aerosol Robotic Network)-based validation of satellite estimates near the city centre at Moscow_MSU_MO and over the Moscow suburbs at Zvenigorod revealed that MAIAC AOT at 0.47 µm is in agreement with AERONET AOT though underestimated by 0.05–0.1 for AOT<1 and overestimated for smoke conditions with AOT>1. The MAIAC AOT biases were almost the same for the Moscow_MSU_MO and Zvenigorod AERONET sites, which indicated that the MAIAC algorithm effectively removed the effect of the bright urban surface in the city centre. For the ground-based measurements, the difference between annual median AOT at Moscow_MO_MSU and Zvenigorod (ΔAOT) varied within −0.002 to +0.03, with statistically significant positive bias for most years, and an average ΔAOT was about 0.02. According to the MAIAC dataset, the ΔAOT varied within ±0.01 and was not statistically significant. The ΔAOT started decreasing recently due to intensive urban development of the territory around Zvenigorod and the decrease in pollutant emissions in Moscow, which is mainly caused by the environmental regulations. According to the MAIAC dataset, the most pronounced spatial AOT differences over the territory of Moscow were observed at the 5 % quantile level, where they reached 0.05–0.06 over several locations and could be attributed to the stationary sources of aerosol pollution, for example, large areas of construction sites, aerosol pollution from roads and highways, or agriculture activities. The differences between the maximum and the mean AOT for different quantiles, except the 95 % quantile, within the Moscow region, were about 0.02–0.04, which could be attributed to the local aerosol sources. The application of the MAIAC algorithm over the whole Moscow region has revealed a decreasing AOT trend over the centre of Moscow and an increasing trend over the “New” Moscow territory which experienced an intensive build-up and agricultural development.

scholarly journals Assessment of urban aerosol pollution over Moscow megacity by MAIAC aerosol product

2019 ◽  
Author(s):  
Ekaterina Y. Zhdanova ◽  
Natalia Y. Chubarova ◽  
Alexei I. Lyapustin
Keyword(s):  
Power Plants ◽  
Agricultural Development ◽  
Moscow Region ◽  
Pollutant Emissions ◽  
City Centre ◽  
The North ◽  
Aerosol Pollution ◽  
Aerosol Sources ◽  
The Difference ◽  
The City

Abstract. We estimated the distribution of aerosol optical thickness (AOT) with a spatial resolution of 1 km over Moscow megacity using MAIAC aerosol product based on MODIS satellite data (Lyapustin et al., 2018) for the warm period of year (May–September). AERONET (Aerosol Robotic Network)-based validation near the city centre at Moscow_MSU_MO and over Moscow suburbs at Zvenigorod revealed that MAIAC AOT at 470 nm is in agreement with AERONET AOT though underestimated by 0.05–0.1 for AOT  1. The MAIAC AOT biases were almost the same for the Moscow_MSU_MO and Zvenigorod AERONET sites, which indicated that MAIAC effectively removed the effect of the bright urban surface in the city centre. For the ground-based measurements, the annual median AOT difference between Moscow_MO_MSU and Zvenigorod (ΔAOT) varied within −0.002±0.03 with statistically significant positive bias for most years and an average ΔAOT of ~ 0.02. According to MAIAC dataset, ΔAOT varied within ±0.01 and was not statistically significant. The ΔAOT started decreasing recently due to intensive urban development of the territory around Zvenigorod and the decrease of pollutant emissions in Moscow, which is mainly caused by the environmental regulations. According to the MAIAC dataset, the most pronounced spatial AOT difference over the territory of Moscow was observed at 5 % quantile level, where it reached 0.05–0.06 over several locations and could be attributed to the stationary sources of aerosol pollution, for example, power plants, or aerosol pollution from roads. The difference between the maximum and the mean AOT for different quantiles, except the 95 % quantile, within the Moscow region, was about 0.02–0.04 which could be attributed to the local aerosol sources. The application of the MAIAC algorithm over the whole Moscow region has revealed a decreasing AOT trend over the centre of Moscow and an increasing trend over the New Moscow territory which experienced an intensive build-up and agricultural development in the north and the south parts of this district, respectively.

Pengetahuan dan pelaksanaan Kemahiran Proses Sains (KPS) dalam dalam kalangan guru

2017 ◽  
Vol 7 (1) ◽  
pp. 56-67
Author(s):  
Saniah Sembak ◽  
Norazilawati Abdullah
Keyword(s):  
Science Teachers ◽  
School Teacher ◽  
Secondary Science Teachers ◽  
School Based ◽  
Significant Difference ◽  
Level Of Knowledge ◽  
The Mean ◽  
The Difference ◽  
Manova Analysis ◽  
The City

This study aims to assess the level of knowledge and the implementation of five Integrated Science Process Skills (ISPS) comprising Build hypothesis, control variables, redefinition In operation, interpreting data and experimenting in School Based Assessment (PBS). In addition, this study is to identify the difference between knowledge and implementation of the ISPS gender and school location. The sample consisted of 407 lower secondary science teachers in Melaka and randomly selected from 66 schools. Quantitative data analysis using SPSS version 19. The instrument consists of a questionnaire (Cronbach Alpha 0.884), and Knowledge Test ISPS and implementation checklist ISPS. Descriptive statistics as a whole that the level of knowledge and implementation of ISPS is moderate (Mean = 3.11 and 32.81). MANOVA analysis found no significant difference in terms of the mean scores of Knowledge and implementation between male and female teachers. While the mean score of knowledge Build hypothesis teachers in rural schools, higher and significantly different than the city school teacher. A number of recommendations put forward to improve the knowledge and implementation of the ISPS teachers. This is expected to meet the goals of the Malaysia Education Blueprint 2013-2025 that is to achieve the vision and aspirations of the student’s education system that can meet the needs of the country in the field of science and technology.

scholarly journals Análisis de las edades, trayectos y minutos de uso en la utilización de un sistema de bicicletas compartidas: el caso del VaiBike en Vilagarcía de Arousa (España) (Analysis of ages, routes, and minutes of use in a shared bicycle system: the case of VaiBi

Retos ◽  
2018 ◽  
pp. 314-319
Author(s):  
Alberto Sanmiguel-Rodríguez
Keyword(s):  
City Centre ◽  
Men And Women ◽  
Obesity And Overweight ◽  
Frequency Of Use ◽  
The Difference ◽  
Las Mujeres ◽  
Shared Bicycle ◽  
Bicycle Sharing System ◽  
The City

La creciente contaminación en las ciudades y el incremento de la obesidad y sobrepeso aconsejan medios de transporte activos. Uno de los sistemas que está en auge en los últimos años es el de bicicletas compartidas de uso público. En la actualidad, en España, apenas existen estudios que aporten información sobre las características de los usuarios y los hábitos de utilización del servicio, por lo que con este estudio se pretende categorizar las edades de los usuarios del sistema de bicicletas compartidas, así como la frecuencia de uso, características de los itinerarios y media de minutos de uso de las bicicletas.                 La edad media de los usuarios, durante la primera etapa del 2009 al 2012, fue de 46 años (hombres 49; mujeres 38.7), siendo las diferencias significativas t=83,06; p <0,001. La mayor frecuencia de uso se inicia y finaliza en el centro de la ciudad (15.947 usos; 18.9%). Los hombres entre 50 y 69 años y las mujeres entre 30 y 49 años son los que más utilizan las bicicletas. Los itinerarios por la costa son los preferidos por las mujeres. La media de minutos de uso de los viajes de las bicicletas públicas fue de 36,1 (hombres 38,1; mujeres 31,4), siendo las diferencias estadísticamente significativas t84181=26,30; p <0,001. Abstract. The growing pollution in cities and the increase in obesity and overweight suggest the use of active means of transport. One of these means is the bicycle sharing system, which has become extremely popular in recent years. Currently, hardly any study provides information about the users’ characteristics and the usage habits of the mentioned service in Spain. Therefore, this study is intended to categorize the ages of users of this system, as well as their frequency of use, the route characteristics, and average minutes of use of bicycles. Users’ average age was 46 years during the first period, from 2009 to 2012 (men 49; women 38.7), the difference between men and women being significant (t=83.06; p<0.001). The highest frequency of use begins and ends in the city centre (15,947 uses; 18.9%). Men between 50 and 69 years old and women between 30 and 49 years old are those who use bicycles the most. Coastal routes are the most popular in women. The average minutes of use in public bicycle trips were 36,1 (men 38,1; women 31,4), with statistically significant differences between genders (t84181=26,30; p<0,001).

scholarly journals PENERAPAN ALGORITMA K-MEDOIDS CLUSTERING UNTUK PENGELOMPOKKAN PENYEBARAN DIARE DI KOTA MEDAN (STUDI KASUS: KANTOR DINAS KESEHATAN KOTA MEDAN)

2019 ◽  
Vol 3 (1) ◽  
Author(s):  
Bambang Riyanto
Keyword(s):  
Data Mining ◽  
Rainy Season ◽  
Clustering Algorithm ◽  
The Mean ◽  
The Difference ◽  
The City

The health office is in charge of instructing and registering diarrhea sufferers in each region, then the area will be evaluated which areas are most affected by diarrhea. And checking directly into the field revealed that the most basic cause was about the unclean environment such as trenches that were too much garbage, causing floods during the rainy season. The health office also encourages the community to always maintain environmental cleanliness and familiarize people to always wash their hands with soap before eating and after cleaning with simple things like this is expected to help reduce diarrhea sufferers in the city of Medan. K-Medoids Clustering is clustering algorithm which is similar to K-Means. The difference between these two algorithms is the K-Medoids or PAM algorithm uses the object as a representative (medoid) as the center of the cluster for each cluster, while the K-Means uses the mean (mean) as the center of the cluster.Keywords: Diarrhea, Service office, Data mining, K-Medoids Algorithm

Modeling Effects of Tidal Barrier Closure of Venice Lagoon

1991 ◽  
Vol 24 (6) ◽  
pp. 149-155 ◽  
Author(s):  
G. T. Orlob ◽  
A. E. Bale ◽  
H. Rajbhandari ◽  
M. Malagoli
Keyword(s):  
Water Quality ◽  
Preliminary Investigation ◽  
Venice Lagoon ◽  
Past Century ◽  
Shallow Lagoon ◽  
The Mean ◽  
The Difference ◽  
Agricultural Areas ◽  
Water Quality Models ◽  
The City

As a combined result of land subsidence and sea level rise in the vicinity of the City of Venice there has been a net decrease in the difference between the mean elevations of land and sea of about 30 centimetres over the past century. This has resulted in an increased incidence of flooding in Venice with occasional disastrous consequences, as in November 1966 when storm and tide conditions combined to flood the Piazza San Marco to depths exceeding one metre. Among the solutions proposed to solve the flooding problem is a modular tidal barrier that is designed to close the three major entrances to the shallow lagoon in which Venice is situated. Because the lagoon is highly eutrophic and circulation is driven primarily by the tide in the Adriatic Sea, there is concern that operation of the barriers could exacerbate an already serious problem of pollution. The lagoon currently receives the untreated waste water from Venice with an organic loading equivalent to more than 400,000 persons during the tourist season, industrial discharges from the Port of Marghera, and non-point accretions of nutrients from adjacent agricultural areas. Preliminary investigation of the effects of the proposed barrier scheme using mathematical hydrodynamic and water quality models suggests that prolonged isolation of the lagoon from the sea, if this should become necessary for flood protection, may enhance primary production and induce unfavorable water quality conditions. This paper presents results of this investigation and offers suggestions for further refinement and application of the models to assist in the environmental impact assessment which must be performed prior to barrier construction.

scholarly journals SIMULATION OF THE INFLUENCE OF VEGETATION ON MICROCLIMATE AND THERMAL COMFORT IN THE CITY OF SÃO PAULO

2019 ◽  
Vol 3 (2) ◽  
pp. 1 ◽  
Author(s):  
Jörg Spangenberg ◽  
Paula Shinzato ◽  
Erik Johansson ◽  
Denise Duarte
Keyword(s):  
Thermal Comfort ◽  
Street Canyon ◽  
Sao Paulo ◽  
City Centre ◽  
São Paulo ◽  
Mean Radiant Temperature ◽  
Speed Up ◽  
The Mean ◽  
Radiant Temperature ◽  
The City

The microclimates of a park, a square and a street canyon were measured on a summer day in the city centre of São Paulo, Brazil. The field monitoring showed that the park was up to 2°C cooler than the square and the canyon. The effect of adding shading trees to the street canyon was simulated for the same day using the numerical model ENVI-met. The simulations showed that incorporating street trees in the urban canyon had a limited cooling effect on the air temperature (up to 1.1°C), but led to a significant cooling of the street surface (up to 12°C) as well as a great reduction of the mean radiant temperature at pedestrian height (up to 24°C). Although the trees lowered the wind speed up to 45% of the maximum values, the thermal comfort was improved considerably as the physiologically equivalent temperature (PET) was reduced by up to 12°C.

scholarly journals Modeling Effects of Climate Change on Air Quality and Population Exposure in Urban Planning Scenarios

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Lars Gidhagen ◽  
Magnuz Engardt ◽  
Boel Lövenheim ◽  
Christer Johansson
Keyword(s):  
Climate Change ◽  
Air Quality ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Ozone Exposure ◽  
City Centre ◽  
Population Exposure ◽  
Nox Emissions ◽  
Road Tunnels ◽  
The City

We employ a nested system of global and regional climate models, linked to regional and urban air quality chemical transport models utilizing detailed inventories of present and future emissions, to study the relative impact of climate change and changing air pollutant emissions on air quality and population exposure in Stockholm, Sweden. We show that climate change only marginally affects air quality over the 20-year period studied. An exposure assessment reveals that the population of Stockholm can expect considerably lower NO2exposure in the future, mainly due to reduced local NOx emissions. Ozone exposure will decrease only slightly, due to a combination of increased concentrations in the city centre and decreasing concentrations in the suburban areas. The increase in ozone concentration is a consequence of decreased local NOx emissions, which reduces the titration of the long-range transported ozone. Finally, we evaluate the consequences of a planned road transit project on future air quality in Stockholm. The construction of a very large bypass road (including one of the largest motorway road tunnels in Europe) will only marginally influence total population exposure, this since the improved air quality in the city centre will be complemented by deteriorated air quality in suburban, residential areas.

scholarly journals Distribution and abundance of the Red Squirrel Sciurus vulgaris in an urbanised environment

2014 ◽  
Vol 63 (3) ◽  
pp. 255-262 ◽  
Author(s):  
Grzegorz Kopij
Keyword(s):  
Group Size ◽  
Density Estimate ◽  
City Centre ◽  
Red Squirrel ◽  
Sciurus Vulgaris ◽  
Late Autumn ◽  
The Mean ◽  
The City

Abstract In late autumn 2004, 160 dreys were found in all parks in Wroclaw (N=21 parks), i.e. 2.8 dreys per 10 ha. In the same period, 145 squirrels, grouped in 69 families, were counted in all these parks (1.23 families per 10 ha). The mean group size (including records of single squirrels) was 1.93 (SD = 1.04; N = 157). The density estimate based on this (number of dreys/mean number of dreys per group) shall be 1.40 families per 10 ha, therefore close to the value based on the number of squirrels counted. Squirrels were most common (64% of all squirrels recorded in parks) in largest parks located c. 2-7 km from the city centre. In forests (N = 12), squirrels density was much lower than in parks (0.1-0.3 families per 10 ha).

scholarly journals Primary Soil Contaminants and Their Risks, and Their Relationship to Myocardial Infarction Susceptibility in Urban Krakow (Poland)

2021 ◽  
Author(s):  
Krystyna Ciarkowska ◽  
Ewa Konduracka ◽  
Florian Gambus
Keyword(s):  
Myocardial Infarction ◽  
Threshold Effect ◽  
City Centre ◽  
Metal Exposure ◽  
Hospitalised Patients ◽  
Polycyclic Aromatic ◽  
Probable Effect ◽  
The Mean ◽  
Industrial Zones ◽  
The City

AbstractWe recorded the concentrations, distributions and sources of 16 polycyclic aromatic hydrocarbons (PAHs), along with zinc (Zn), lead (Pb) and cadmium (Cd), in soils from different areas of Krakow––the city-centre, industrial and residential zones––and from outside the city. Their relationships to the soil properties were examined, and associations were established between the soil pollution in the different areas and myocardial infarction (MI) incidences in 5054 hospitalised patients who had lived in Krakow for more than 30 years. The PAH and Cd concentrations exceeded threshold-effect levels in the city-centre and industrial zones, while Zn, Pb and phenanthrene exceeded probable-effect levels. Industrial incineration processes, coal combustion and petrol-powered vehicles are the main sources of the PAHs, Zn and Cd, while the Pb originates mainly from historical accumulation and the use of Pb-enriched petrol. The mean number of MI incidences in Krakow equated to 0.72% of the residents, while in the city-centre and industrial zones it was ~ 2.8 and 1.2%, respectively. In the residential zone, the mean number of MI incidences was < 0.5% of the residents. These results may suggest that differences in MI incidence in Krakow residents is, at least in part, linked to chronic PAH and heavy-metal exposure.

Sign in / Sign up

Export Citation Format

Share Document