COVID-19 strict lockdown impact on urban air quality and atmospheric temperature in four megacities of India

COVID-19 pandemic has forced to lockdown entire India starting from 24th March 2020 to 14th April 2020 (first phase), extended up to 3rd May 2020 (second phase), and further extended up to 17th May 2020 (third phase) with limited relaxation in non-hotspot areas. This strict lockdown has severely curtailed human activity across India. Here, aerosol concentrations of particular matters (PM) i.e., PM₁₀, PM_2.5, carbon monoxide (CO), nitrogen dioxide (NO₂), sulphur dioxide (SO₂), ammonia (NH₃) and ozone (O₃), and associated temperature fluctuation in four megacities (Delhi, Mumbai, Kolkata, and Chennai) from different regions of India were investigated. In this pandemic period, air temperature of Delhi, Kolkata, Mumbai and Chennai has decreased about 3 °C, 2.5 °C, 2 °C and 2 °C respectively. Compared to previous years and pre-lockdown period, air pollutants level and aerosol concentration (?41.91%, ?37.13%, ?54.94% and ?46.79% respectively for Delhi, Mumbai, Kolkata and Chennai) in these four megacities has improved drastically during this lockdown period. Emission of PM_2.5 has experienced the highest decrease in these megacities, which directly shows the positive impact of restricted vehicular movement. Restricted emissions produce encouraging results in terms of urban air quality and temperature, which may encourage policymakers to consider it in terms of environmental sustainability.     

Assessment of spatial variations of particulate matter (PM<Subscript>10</Subscript> and PM<Subscript>2.5</Subscript>) in Bahrain identified by air quality index (AQI)

The rapid urbanization, industrialization, modernization, and the frequent Middle Eastern dust storms have negatively impacted the ambient air quality in Bahrain. The objective of this study is to identify the most critical atmospheric air pollutants with emphasis on their potential risk to health based on calculated AQI (air quality index) values using EPA approach. The air quality datasets of particulate matters (PM₁₀ and PM_2.5), ozone (O₃), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and carbon monoxide (CO) were measured in January 2012 and August 2012 using five mobile air quality monitoring stations located at different governorates. The results of this study demonstrated that PM₁₀ and PM_2.5 are the most critical air pollutants in Bahrain with PM_2.5 prevailing during January 2012 and PM₁₀ prevailing during August 2012. The corresponding AQI categories were utilized to evaluate spatial variability of particulate matters in five governorates. The impact of meteorological factors such as ambient air temperature, wind speed, relative humidity, and total precipitation on ambient air quality were discussed. The analysis demonstrated that the highest PM₁₀ concentrations were observed in the Northern Governorate while the highest PM_2.5 concentrations were observed in the Capital, Central, and Northern Governorates during August 2012. It was observed that the levels of PM_2.5 pollution were higher within proximity of the industrial zone. The results suggested that the average PM_2.5/PM₁₀ ratio in August 2012 was lower than in January 2012 due to the Aeolian processes. This study concludes that higher wind speed, total precipitation, relative humidity rates, and lower ambient air temperature in January 2012 assisted with the dissipation of particulate matter thus lowering the pollution levels of both PM₁₀ and PM_2.5 in comparison to August 2012.     

A cheap and third-age-friendly home device for monitoring indoor air quality

Nowadays, thanks to the hardware costs reduction everyone at home owns at least one hi-technology devices to support life quality. This paper proposes a new methodology to analyse the indoor air quality with a cheap and third-age-dedicated device. A new prototype, called Home Pollution Embedded System (HOPES), was developed to give simple and understandable information, also comprehensible for people with cognitive problems or that are not familiar with new technologies. The device gathers pollutants data and displays to the user different air pollutants concentrations, from toxics gasses up to explosives. Moreover, an overall air quality index has been elaborated and is displayed by HOPES with lights and numerical information. HOPES is an Internet of things device that works in real time and that can be connected to the web and to a geographic information system platform to add spatial information of each pollutant. The hardware architecture employs a set of gas semiconductor sensors and an IR particulate matter sensor. Experimental results demonstrated that HOPES has an accurate sensor response and is suitable to be used with the proposed indices. In fact, despite of the poor-selective metal oxide sensors, the results highlighted how it is possible to get useful air quality information with a cheap device. However, the system needs more tests to validate the sensors array with different substances.     

Temporal analysis of air pollution and its relationship with meteorological parameters in Bahrain, 2006–2012

The objective of this paper is to analyze temporal and seasonal trends of air pollution in Bahrain between 2006 and 2012 by utilizing datasets from five air quality monitoring stations. The non-parametric and robust Theil-Sen approach is employed to study quantitatively temporal variations of particulate matter (PM₁₀ and PM_2.5), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and ozone (O₃). The calculated annual concentrations for PM₁₀ and PM_2.5 in Bahrain were substantially higher than recommended World Health Organization (WHO) guideline standards. Results showed increasing trends for PM₁₀, PM_2.5, and SO₂ whereas O₃ and its precursor NO₂ showed decreasing behavior. The general increase in air pollution trends is in agreement with prediction of air pollution models for Middle East region due to economic growth, industrialization, and urbanization. The significances of long-term trends were examined. Additional to actual (unadjusted) trends, meteorological adjusted (deseasonalized) trends and seasonal trends were quantified. The box-plot analysis visually illustrated monthly variations of key air pollutants. It showed that only PM₁₀ and PM_2.5 exhibited seasonal pattern, and their concentrations increased during summer and decreased during winter. The effects of ambient air temperature, relative humidity, wind speed, and rainfall on particulate matter (PM) concentrations were further investigated. The Spearman correlation coefficient results demonstrated significant negative correlation between relative humidity and PM concentrations (??0.595 for PM₁₀ and ??0.526 for PM_2.5) while significant positive correlation was observed between temperature and PM concentrations (0.420 for PM₁₀ and 0.482 for PM_2.5).     

基于PDA的雨水情查询系统设计与应用

水利信息化的不断发展,使得在防汛现场获得实时水文信息成为可能。分析了基于PDA的雨水情查询系统的关键问题,并介绍了系统设计和应用示例。系统以实时雨水情数据库为基础,基于移动网络技术和PDA设备,设计实现了随时随地查询防汛雨水情信息及各类图片文档等信息的功能,为防汛指挥决策提供了技术支撑。     

基于时间算子的煤矿监控系统查询机制设计

数据查询是监控系统的核心功能之一,有效的数据监控需建立在灵活、高效的数据查询机制之上。但目前,煤矿监控系统查询机制仅关注单一传感器数值变化情况,无法针对不同对象及同一对象不同时间段等查询,限制了煤矿监控系统作用。设计了一种基于时间算子的事件驱动查询机制,为增强煤矿监控系统查询能力提供基础支撑。      

山西省煤炭资源有效保障能力分析信息系统设计与开发

在分析以往煤炭资源管理信息系统优缺点的基础上,利用Visual C＋＋6．0、SQL Server2000、ADO技术以及MapGIS二次开发技术,开发了山西省煤炭资源有效保障能力分析信息系统。该系统具有数据管理、信息查询、地图操作、统计输出、环境承载力评价、煤炭用途评价、煤炭优质环保评价、矿井资源保障度评价、估算井田生产规模等功能,为煤炭资源管理提供适时、动态和高效有序的资源数据,为加强煤炭资源的开发部署及管理,制定能源政策以及中长期规划,合理开发利用煤炭资源,保障煤炭工业可持续发展提供科学的宏观决策依据。     

Risk assessment of traffic-related air pollution in a world heritage city

To support environmental risk management in a world heritage city, this paper presents high spatial-resolution maps of air pollutants for the Macao Peninsula. In particular, the risk of exposure to traffic-related nitrogen dioxide pollution for the 22 world heritage monuments in the Historic Center of Macao was assessed. The air-pollution mapping was performed by a building-based air quality model system, in which the traffic-related air pollutions at 5,965 receptor points in the Macao Peninsula were modeled and the average spatial resolution was 727 receptors/km². The results indicate that under the conditions of the evening peak hour and the north wind direction sector 0–20°, air quality in the Macao Peninsula is the worst. About 14.1% of the modeled nitrogen dioxide concentrations at the 5,965 receptor points exceed the national ambient air quality standard for scenic spot of 120 μg/m³ in China. Two world heritage monuments, i.e., the “Leal Senado” Building and the Cathedral, are exposed to excessively high nitrogen dioxide concentrations of 135.9 and 121.1 μg/m³, respectively. The results in this paper could help decision makers to develop effective strategies to protect the world cultural heritages in Macao for future human generations to appreciate and enjoy.     

Environmental and geologic application of solid-state methane sensors

The analysis of methane concentration in natural systems, such as soil, water and atmosphere, is becoming an important and delicate task for environmental research. (1)The characterization of the spatial and temporal variability of these emissions is an important and urgent target for greenhouse-gas and global change studies. In this respect a series of technical specifications are demanded by the scientific community, including sensor portability, low detection limit and the need of analyzing small volumes of gas. Solid-state gas sensors are increasingly used for environmental measurements. A metal oxide semiconductor (e.g., SnO₂, ZnO₂,) is used to fabricate chemical sensors for several gases, in particular methane. The potential of this technique is based on the low conductivity of the material in clean air, which increases with the methane gas concentration in the air. Sensitivity, selectivity, power consumption, long-term stability, and reaction time are all linked together. They all depend on the physico-chemical and geometrical structure of the sensitive layer. This means that improving one parameter has an influence on the others. Therefore, it is necessary to make compromises and select the combination of performances that best meet the application requirements.     

GMM—a gas monitoring module for long-term detection of methane leakage from the seafloor

A new seafloor lander module, the Gas Monitoring Module (GMM), has been developed for continuous and long-term measurements of methane concentration in seawater at the benthic boundary layer, as a result of marine environmental geology and technology synergy. The module is designed to host a series of sensors controlled and managed by a data acquisition and control system able to perform first-level data quality checks. The prototype includes semiconductor methane sensors, an H₂S sensor and a CTD for temperature, salinity, pressure recording, as well as interfaces for additional sensors. The GMM can be linked to submarine cables for real-time data transmission to onshore operators and is suitable for long-term monitoring of natural gas emissions from seafloor or leakages from pipelines and boreholes.     

分布式基坑监测信息管理与预警系统的研制

针对基坑监测的信息化、集成化、共享化要求,开发了基于GIS的分布式基坑监测信息管理与预警系统。介绍了系统的结构框架,着重介绍了系统实现的功能。在GIS图形可视化技术基础上,系统地实现了区域内多个基坑地质勘察、设计、施工等资料及测点信息、监测仪器、监测数据、周边建筑物等相关资料的全面采集,并在此基础上实现了信息的存储、处理、分析、查询、预测、预警以及成果输出的自动化。系统采用C/S结构实现信息共享与多人协作,在网络环境下可高效运行,为基坑监测提供了一个功能强大的信息平台。     

矿山环境可持续发展决策支持系统空间数据库设计与开发

介绍了矿山环境决策支持系统空间数据库设计思路、构成、功能以及系统建立的主要技术环节.该数据库包括10个子空间数据库.该数据库提供信息输入、空间检索和查询、空间分析、输出功能.矿山环境决策支持决策系统空间数据库的建立将为矿山开发与环境保护协调发展提供帮助.     

贵州省石炭纪早期古土壤的发现及其意义

古土壤蕴涵着古老时期的大气氧、二氧化碳以及生态植被的演化信息 ,利用有效的手段提取这些信息并据此推测古气候环境。在贵州省的遵义苟江、道真县、正安县等地发现了保存完好的石炭纪早期的古土壤剖面 ,为恢复该地质时期云贵高原的大气氧演化、二氧化碳浓度与生态植被提供了天然的现场条件。     

CO2 geological storage: The environmental mineralogy perspective

Geological storage of carbon dioxide (CO₂) is one of the options envisaged for mitigating the environmental consequences of anthropogenic CO₂ increases in the atmosphere. The general principle is to capture carbon dioxide at the exhaust of power plants and then to inject the compressed fluid into deep geological formations. Before implementation over large scales, it is necessary to assess the efficiency of the process and its environmental consequences. The goal of this paper is to discuss some environmental mineralogy research perspectives raised by CO₂ geological storage.     

Assessment of greenhouse gas emissions from coal and natural gas thermal power plants using life cycle approach

The importance of mitigation of climate change due to greenhouse gas (GHG) emissions from various developmental and infrastructure projects has generated interest at global level to reduce environmental impacts. Life cycle assessment may be used as a tool to assess GHG emissions and subsequent environmental impacts resulting from electricity generation from thermal power plants. This study uses life cycle approach for assessing GHG emissions and their impacts due to natural gas combined cycle (NGCC) and imported coal thermal power plants using the IPCC 2001 and Eco-Indicator 99(H) methods in India for the first time. The total GHG emission from the NGCC thermal power plant was 584 g CO₂ eq/kWh electricity generation, whereas in case of imported coal, it was 1,127 g CO₂ eq/kWh electricity generation. This shows that imported coal has nearly ~2 times more impacts when compared to natural gas in terms of global warming potential and human health as disability-adjusted life years from climate change due to GHG emissions such as carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O).     

Improving the indoor air quality using the individual air supply system

Indoor air quality attracts great interest. Many dwellings are ventilated naturally. The article presents the gravity system conversion into individual air supply system, which can be equipped with air fan. This solution’s impact on the interior microclimate was analyzed. The proposed solution uses the lower natural ventilation ducts sections, which are not normally used as air supply channels to bring air to the housing. Exhaust grilles were located in the adjacent rooms. Individual air supply system with switched off fan improves indoor air quality insufficiently; however, switching on the device causes a very significant change. A large carbon dioxide concentration reduction (which was used as an air quality indicator) has been confirmed by rigorous statistical analysis, the results of which were presented in the article.     

基于MapObjects的C/S管线信息系统的设计与实现

基于面向对象的地理信息系统技术，针对客户机／服务器(C／S)模式设计了一个包含数据库、应用服务器和客户端三个部分的管网管线地理信息系统。该系统由测量调查、图形编辑、数据统计、信息查询、空间分析、规划、资料输出、权限管理、系统维护九大功能模块组成；并具有用户界面友好，稳定实用，安全可靠，可扩充性强等特点。并在数据存储方式、图形数据与属性数据的连接、编辑功能设计、系统兼容性、符号库建立等关键技术的实现方面有新的突破。该系统除具有一般管理系统的基本功能外，还具有地理信息系统所特有的空间数据查询和分析功能；该系统还充分发挥了网络的优势,为CIS信息社会化共享提供了一个切实可行的解决方案。     

Gaseous air pollution background estimation in urban,suburban, and rural environments

There is a great demand for estimating the ambient air pollutant background concentrations in order to assess the effectiveness of different emission control strategies. In this paper, the background concentrations of four pollutants, namely sulfur dioxide (SO₂), nitrogen oxides (NOx), carbon monoxide (CO), and ozone (O₃) pollutants in urban, suburban, and rural environments were investigated using Kolmogorov–Zurbenko (KZ) filter technique. Air quality data from monitoring stations over a period of 4 years (2007–2010) was analyzed for three locations in Kuwait, namely urban, suburban, and rural. The spatial and temporal (daily, weekly, and monthly) variations of the four pollutants were analyzed. The results show that the levels of ambient air pollutant background concentrations were high in the urban site compared to suburban and rural area. The diurnal variation of SO₂ concentration showed an early morning peak, while the diurnal variation of NOx concentration constituted has two peaks, one was in the early morning hours (5 to 8 a.m.) and the second was in nighttime hours (8 to 11 p.m.). These two peaks were observed at all three locations. The monthly background NOx concentration reached a maximum in winter and minimum in summer. Diurnal variation of CO concentration showed a similar trend to SO₂ concentrations in all three locations. Because of the photochemical reactions that occur in the atmosphere, the background concentration of O₃ showed an inverse relation with respect to background concentration of NOx.     

基于Intranet的地热地理信息系统的设计与实现

通过建立Intranet网络及地热地理信息系统,为地热资源的可持续开发利用提供帮助.该系统具有数据存储、数据查询、数据更新功能,涉及资源管理、技术开发、开采监测等三个方面;具有空间查询及分析功能,图形信息与属性信息可以相互查询,也可以独立查询,空间分析功能包括资源量计算、资源开发评价等;自动制图功能,可自动绘制井身结构图、地层柱状图等多种标准图.     

基于MapObjects的威海市经济技术开发区地籍查询系统的设计与实现

该文介绍了威海市经济技术开发区地籍查询系统的设计与开发过程。系统开发的主要目的是为威海市经济技术开发区提供简单的地籍管理与查询平台。系统集成了现代电子地图预览、简单的查询与分析以及3D数字威海预览等功能,充分利用了第二次全国土地利用调查的成图数据,实现了地理信息系统应有的效用。