The Global Impacts of COVID-19 Lockdowns on Short-Lived Climate Forcers: Highlights from a Critical Review

2021 ◽  
Author(s):  
Georgios Gkatzelis ◽  
Jessica Gilman ◽  
Steven Brown ◽  
Henk Eskes ◽  
Rita Gomes ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Current Knowledge ◽  
Atmospheric Pollutants ◽  
Future Research ◽  
Data Sets ◽  
Government Interventions ◽  
Pollutant Concentrations ◽  
Transportation Sector ◽  
Global Impacts ◽  
The Government

<p>The coronavirus-19 (COVID-19) pandemic led to government interventions to limit the spread of the disease that are unprecedented in the last decades. Stay at home orders and other measures led to sudden decreases in atmospheric emissions, most visibly from the transportation sector. We present a review of the current knowledge and understanding of the influence of these emission reductions on atmospheric pollutants concentration and notably air quality with a focus on NO<sub>2</sub>, PM<sub>2.5</sub>, and O<sub>3</sub> based on more than 200 papers utilizing observations from ground-based and satellite remote sensing instruments. We use the government stringency index as an indicator for the severity of lockdown measures and show how key air pollutants change as the stringency index increases. Changes in NO<sub>2</sub> and PM<sub>2.5</sub> mass concentration are well-studied globally. The observed decrease of NO<sub>2</sub> with increasing stringency index is in general agreement with emission inventories that account for the lockdown. Due to the important influence of atmospheric chemistry on O<sub>3</sub> and PM<sub>2.5</sub> concentrations, their responses may not be linear with respect to primary pollutants. At most sites, we found O<sub>3</sub> increased, whereas PM<sub>2.5</sub> decreased slightly, with increasing stringency index. Changes in the PM<sub>2.5</sub> composition are found to be understudied and not well-quantified so far. We highlight future research needs for utilizing the emerging data sets covering a full seasonal cycle as a preview of a future state of the atmosphere in a world with targeted permanent reductions of emissions. Finally, we emphasize the need to account for the effects of meteorology, long-term trends, and atmospheric chemistry when determining the lockdown effects on pollutant concentrations, especially on PM<sub>2.5</sub>.</p>

scholarly journals The global impacts of COVID-19 lockdowns on urban air pollution

Elem Sci Anth ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Georgios I. Gkatzelis ◽  
Jessica B. Gilman ◽  
Steven S. Brown ◽  
Henk Eskes ◽  
A. Rita Gomes ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Urban Air Pollution ◽  
Future Research ◽  
Specific Method ◽  
Data Sets ◽  
Atmospheric Pollutant ◽  
Government Interventions ◽  
Pollutant Concentrations ◽  
Global Impacts ◽  
The Government

The coronavirus-19 (COVID-19) pandemic led to government interventions to limit the spread of the disease which are unprecedented in recent history; for example, stay at home orders led to sudden decreases in atmospheric emissions from the transportation sector. In this review article, the current understanding of the influence of emission reductions on atmospheric pollutant concentrations and air quality is summarized for nitrogen dioxide (NO2), particulate matter (PM2.5), ozone (O3), ammonia, sulfur dioxide, black carbon, volatile organic compounds, and carbon monoxide (CO). In the first 7 months following the onset of the pandemic, more than 200 papers were accepted by peer-reviewed journals utilizing observations from ground-based and satellite instruments. Only about one-third of this literature incorporates a specific method for meteorological correction or normalization for comparing data from the lockdown period with prior reference observations despite the importance of doing so on the interpretation of results. We use the government stringency index (SI) as an indicator for the severity of lockdown measures and show how key air pollutants change as the SI increases. The observed decrease of NO2 with increasing SI is in general agreement with emission inventories that account for the lockdown. Other compounds such as O3, PM2.5, and CO are also broadly covered. Due to the importance of atmospheric chemistry on O3 and PM2.5 concentrations, their responses may not be linear with respect to primary pollutants. At most sites, we found O3 increased, whereas PM2.5 decreased slightly, with increasing SI. Changes of other compounds are found to be understudied. We highlight future research needs for utilizing the emerging data sets as a preview of a future state of the atmosphere in a world with targeted permanent reductions of emissions. Finally, we emphasize the need to account for the effects of meteorology, emission trends, and atmospheric chemistry when determining the lockdown effects on pollutant concentrations.

Civil Wars, Scientific Study of

2014 ◽  
Author(s):  
Idean Salehyan ◽  
Clayton L. Thyne
Keyword(s):  
Civil War ◽  
Civil Wars ◽  
Civil Conflict ◽  
Future Research ◽  
Data Sets ◽  
Conflict Duration ◽  
Breeding Grounds ◽  
The Government ◽  
Negative Impacts ◽  
External Actors

Civil war is an armed conflict between the state and another organized domestic party over a contested political incompatibility, which results in a number of casualties exceeding a certain threshold for both parties. Attempts to operationalize these criteria have produced many data sets, which conceptualize civil war as distinct from one-sided violence, organized crime, and communal fighting. Civil wars are devastating for states experiencing them, their neighbors, and the entire global community. Combatant and civilian deaths, rape, massive refugee flight, negative impacts on economy and infrastructure, spread of infectious diseases, global spread of illegal narcotics, and the promotion of terrorism are all consequences of civil wars. Theories explaining why civil wars occur focus on objectives of the rebels, ability of rebels to successfully challenge the government, influence of external actors on interactions between the government and the opposition, external financing of potential rebel groups, and impact of a state’s neighbors on the likelihood of civil conflict or how neighboring conflicts and refugee communities serve as breeding grounds for cross-border rebel movements. Conflicts persist until neither side believes that it can achieve unilateral victory and continued fighting is costly. Governments are more likely to win early when they have large armies, but time to government victory increases when they are faced with secessionist rebels and when external parties are involved. Meanwhile, external mediation diminishes informational and credible commitment problems during bargaining and reduces conflict duration. Promising directions for future research on civil war include geographic disaggregation, survey research, and computational/agent-based modeling.

scholarly journals Review of environmental performance of permeable pavement systems: state of the knowledge

2013 ◽  
Vol 48 (3) ◽  
pp. 203-222 ◽  
Author(s):  
Jennifer A. P. Drake ◽  
Andrea Bradford ◽  
Jiri Marsalek
Keyword(s):  
Environmental Performance ◽  
Current Knowledge ◽  
Polyaromatic Hydrocarbons ◽  
Future Research ◽  
Permeable Pavement ◽  
Current State ◽  
Pollutant Concentrations ◽  
The Usa ◽  
Guidance Documents ◽  
And Performance

Permeable pavement (PP) systems provide opportunities to mitigate the impacts of urbanization on receiving water systems by providing at source treatment and management of stormwater. However, they do not receive mainstream use throughout much of Canada and the USA because of a lack of local guidance documents, demonstration projects and performance data. Studies have repeatedly shown that PPs attenuate stormwater flows by reducing volume and frequency of stormwater flows, reducing and delaying peak flow rates, and increasing flow durations. PP systems have been shown to improve stormwater quality by reducing stormwater temperature, pollutant concentrations and pollutant loadings of suspended solids, heavy metals, polyaromatic hydrocarbons, and some nutrients. This review is intended as a comprehensive summary of the current state of knowledge of the environmental performance of PP systems. Published research is synthesized to examine the hydrologic performance, impacts to water quality, longevity and functionality and maintenance needs of PP systems. Where appropriate, the limitations of current knowledge are discussed and emerging and future research needs are presented. The intent of this review is to provide stakeholders in stormwater management with the critical information that is needed to foster acceptance of PPs as a viable alternative to traditional systems.

scholarly journals Tropospheric aerosol hygroscopicity measurements in China

2020 ◽  
Author(s):  
Chao Peng ◽  
Yu Wang ◽  
Zhijun Wu ◽  
Lanxiadi Chen ◽  
Ru-Jin Huang ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Current Knowledge ◽  
Chemical Reactivity ◽  
Measurement Data ◽  
Field Studies ◽  
Critical Discussion ◽  
Future Research ◽  
Tropospheric Aerosol ◽  
State Chemical ◽  
Aerosol Hygroscopicity

Abstract. Hygroscopicity largely determines phase state, chemical reactivity, optical properties and cloud nucleation activities of aerosol particles, thus significantly affecting their impacts on visibility, atmospheric chemistry and climate. In the last twenty years a large number of field studies have investigated hygroscopicity of tropospheric aerosols in China under sub- and super-saturated conditions. Aerosol hygroscopicity measurements in China are reviewed in this paper: 1) a comprehensive summary and critical discussion of aerosol hygroscopicity measurements in China is provided; 2) available measurement data are compiled and presented under a consistent framework to enhance their accessibility and usability; 3) current knowledge gaps are identified, and an outlook which could serve as guidelines for planning future research is also proposed.

scholarly journals Tropospheric aerosol hygroscopicity in China

2020 ◽  
Vol 20 (22) ◽  
pp. 13877-13903
Author(s):  
Chao Peng ◽  
Yu Wang ◽  
Zhijun Wu ◽  
Lanxiadi Chen ◽  
Ru-Jin Huang ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Current Knowledge ◽  
Chemical Reactivity ◽  
Measurement Data ◽  
Field Studies ◽  
Critical Discussion ◽  
Future Research ◽  
Tropospheric Aerosol ◽  
State Chemical ◽  
Aerosol Hygroscopicity

Abstract. Hygroscopicity largely determines phase state, chemical reactivity, optical properties, and cloud nucleation activities of aerosol particles, thus significantly affecting their impacts on visibility, atmospheric chemistry, and climate. In the last 20 years, a large number of field studies have investigated the hygroscopicity of tropospheric aerosols in China under subsaturated and supersaturated conditions. Aerosol hygroscopicity measurements in China are reviewed in this paper: (1) a comprehensive summary and critical discussion of aerosol hygroscopicity measurements in China are provided; (2) available measurement data are compiled and presented under a consistent framework to enhance their accessibility and usability; and (3) current knowledge gaps are identified, and an outlook which could serve as guidelines for planning future research is also proposed.

Landscape Influences on Stream Habitats and Biological Assemblages

2006 ◽  
Keyword(s):  
Current Knowledge ◽  
River Network ◽  
Future Research ◽  
Data Sets ◽  
River Ecology ◽  
River Systems ◽  
Knowledge Gaps ◽  
Spatial And Temporal Scales ◽  
Network Characteristics ◽  
Decision Tools

<em>Abstract.</em>—Viewing river systems within a landscape context is a relatively new and rapidly developing approach to river ecology. Although the linkages among landscapes and associated physicochemical and biological characteristics of rivers have long been recognized, the development of conceptual frameworks and tools for measuring and synthesizing such linkages is relatively recent. In this book, authors from the United States and Canada explore new ideas about landscape–river relationships, river research, and river management; compile large regional, spatially referenced, survey data sets on river network characteristics; explore and describe patterns and relationships across survey sites, reaches, and catchments; and develop management and decision tools. In synthesizing these chapters, we have identified key challenges to studying and managing landscape–river systems. Key challenges include identifying appropriate units of measurement and interpretation of the river network, understanding how human alterations of land cover modify river characteristics and biological assemblages, understanding and measuring how various spatial-scale factors interactively influence instream habitat and biota, and collecting and gathering appropriate landscape and instream habitat data. This book also reveals the major current knowledge gaps that deserve more attention in landscape–river ecology. These include improving river–landscape classification, capturing appropriate spatial- and temporal-scale data, developing accurate predictive models where study data are limited, and improving our ability to measure connectivity among river segments and their networks. Future research that focuses on overcoming the challenges and filling the knowledge gaps will substantially improve our understanding of river ecosystems, fuel the development of tools for linking the functions and processes operating at different spatial- and temporal-scales, and stimulate the development of new hypotheses and frameworks to provide foundations for the next phases of riverine science and management.

scholarly journals A biological basis for planned burning

2012 ◽  
Vol 124 (1) ◽  
pp. 7 ◽  
Author(s):  
David Cheal
Keyword(s):  
Current Knowledge ◽  
Future Research ◽  
Management Approach ◽  
Data Sets ◽  
Management Processes ◽  
Fire Planning ◽  
Anthropogenic Fires ◽  
Experimental Management ◽  
Current Knowledge Base ◽  
Fire Intervals

Fires in Victoria have shaped the vegetation for many millennia. Anthropogenic fires have been used to manage the landscape, initially as an agricultural tool, latterly for ecological reasons and as a means of minimizing the damage done by wildfires. Some characteristics of Victoria’s fire planning and management processes are discussed, such as the requirement for maintenance of biodiversity values and the Adaptive Experimental Management approach being followed. Similarly, some of the most critical regeneration characteristics of plants and vegetation types are highlighted and how these affect burning plans. Given the lack of fully-populated data sets various synthetic whole-of-ecosystem approaches are necessary and the derivation and application of one of these (establishment of Maximum and Minimum Tolerable Fire Intervals) is presented. Ecological constraints on existing (fire and fuel) management are discussed and directions for future research and on-going management considered, including the gaps in our current knowledge base.

Contemporary Employee Recruitment Practices and Areas of Future Research in Indian Railways

Think India ◽  
2019 ◽  
Vol 22 (2) ◽  
pp. 745-763
Author(s):  
Akhila Rao ◽  
Shailashri V. T ◽  
Molly Sanjay Chaudhuri ◽  
Kondru Sudheer Kumar
Keyword(s):  
Selection Process ◽  
Secondary Data ◽  
Manpower Planning ◽  
Future Research ◽  
Technological Advancement ◽  
Employee Recruitment ◽  
Recruitment Practices ◽  
Modern Business ◽  
The Government ◽  
Recruitment And Selection

The modern business milieu is highly competitive due to vast technological advancement which makes employees a vital source of competitive advantage. Precisely, the recruitment process has become a key determinant of an organization’s success and a logistic capital resource to the human resource; thus, the process should be entirely modern. A conventional recruitment and selection process comprises of job analysis, manpower planning, and recruitment and selection. The current study seeks to explore employee recruitment practices and proposes areas of future research in Indian Railways using secondary data. It also gives recommendations on how to improve the recruitment practices in the government-owned Indian Railways. The trends investigated in the study include the applicant tracking software (ATS), use of video resumes, Chatbots, the utilization of social networks, and increased focus on passive candidates.

The Zoning System for Strategy Development of SMEs Go Online: A Literature Review

2018 ◽  
Author(s):  
Sumitro Sarkum
Keyword(s):  
Development Strategy ◽  
Online Marketing ◽  
Strategy Development ◽  
Future Research ◽  
Information And Communication ◽  
Qualitative Descriptive ◽  
The Government ◽  
Market Needs ◽  
Marketing Information ◽  
Relationship Of

This study aims to figure out what the relationship of empowerment of SMEs through methods of zoning as marketing strategy of SMEs in two different markets (offline and online). The zoning strategy with information and communication system integrated brings together socialization and promotion in a market. This system can help the government in taking and formulating policies to unite SMEs in a new market by not leaving the old market. The method in this study uses qualitative descriptive. There are three propositions produced in this initial research, the first; Offline and online marketing is very relevant for SMEs in Indonesia. Second; marketing information system is access for SMEs to find out the demand or market needs both domestically and internationally. And third; The zoning system can be used as an online development strategy for SMEs to synchronize two different markets, namely offline and online. Further research is needed to validate the propositions found, to generate hypotheses and empirical evidence, we recommend using mix methods for future research.

Amruthapala (Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter): A Comprehensive Review on Diversity, Therapeutic Uses, and Valorization of Bioactive Constituents

2019 ◽  
Vol 20 (5) ◽  
pp. 376-389 ◽  
Author(s):  
Sonali Mishra ◽  
Nupur Srivastava ◽  
Velusamy Sundaresan ◽  
Karuna Shanker
Keyword(s):  
Secondary Metabolite ◽  
Current Knowledge ◽  
Experimental Studies ◽  
Critical Discussion ◽  
Future Research ◽  
Bioactive Constituents ◽  
Medicinal Uses ◽  
Comprehensive Review ◽  
Therapeutic Uses ◽  
Decalepis Arayalpathra

Background: Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter is used primarily for nutrition besides its therapeutic values. Traditional preparations/formulations from its tuber are used as a vitalizer and blood purifier drink. The folklore medicinal uses cover inflammation, cough, wound healing, antipyretic, and digestive system management. A comprehensive review of the current understanding of the plant is required due to emerging concerns over its safety and efficacy. Objective: The systematic collection of the authentic information from different sources with the critical discussion is summarised in order to address various issues related to botanical identity, therapeutic medicine, nutritional usage, phytochemical, and pharmacological potentials of the D. arayalpathra. Current use of traditional systems of medicine can be used to expand future research opportunities. Materials and Methods: Available scripted information was collected manually, from peered review research papers and international databases viz. Science Direct, Google Scholar, SciFinder, Scopus, etc. The unpublished resources which were not available in database were collected through the classical books of ‘Ayurveda’ and ‘Siddha’ published in regional languages. The information from books, Ph.D. and MSc dissertations, conference papers and government reports were also collected. We thoroughly screened the scripted information of classical books, titles, abstracts, reports, and full-texts of the journals to establish the reliability of the content. Results: Tuber bearing vanilla like signature flavor is due to the presence of 2-hydroxy-4-methoxybenzaldehyde (HMB). Among five other species, Decalepis arayalpathra (DA) has come under the ‘critically endangered’ category, due to over-exploitation for traditional, therapeutic and cool drink use. The experimental studies proved that it possesses gastro-protective, anti-tumor, and antiinflammatory activities. Some efforts were also made to develop better therapeutics by logical modifications in 2-Hydroxy-4-methoxy-benzaldehyde, which is a major secondary metabolite of D. arayalpathra. ‘Amruthapala’ offers the enormous opportunity to develop herbal drink with health benefits like gastro-protective, anti-oxidant and anti-inflammatory actions. Results: The plant has the potential to generate the investigational new lead (IND) based on its major secondary metabolite i.e. 2-Hydroxy-4-methoxy-benzaldehyde. The present mini-review summarizes the current knowledge on Decalepis arayalpathra, covering its phytochemical diversity, biological potentials, strategies for its conservation, and intellectual property rights (IPR) status. Chemical Compounds: 2-hydroxy-4-methoxybenzaldehyde (Pubchem CID: 69600), α-amyrin acetate (Pubchem CID: 293754), Magnificol (Pubchem CID: 44575983), β-sitosterol (Pubchem CID: 222284), 3-hydroxy-p-anisaldehyde (Pubchem CID: 12127), Naringenin (Pubchem CID: 932), Kaempferol (Pubchem CID: 5280863), Aromadendrin (Pubchem CID: 122850), 3-methoxy-1,2-cyclopentanedione (Pubchem CID: 61209), p-anisaldehyde (Pubchem CID: 31244), Menthyl acetate (Pubchem CID: 27867), Benzaldehyde (Pubchem CID: 240), p-cymene (Pubchem CID: 7463), Salicylaldehyde (Pubchem CID: 6998), 10-epi-γ-eudesmol (Pubchem CID: 6430754), α -amyrin (Pubchem CID: 225688), 3-hydroxy-4-methoxy benzaldehyde (Pubchem CID: 12127).

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