scholarly journals Annual Variation of Global Air Pollution: Initial Aerosol Effect or Climate Interaction?

2021 ◽  
Vol 9 ◽  
Author(s):  
Huihui Feng ◽  
Ying Ding ◽  
Bin Zou ◽  
Chuanfeng Zhao

The aerosol at the previous time (initial aerosol) and climate conditions control the next step annual variation of global air pollution through the complex aerosol-climate interaction. However, the individual influences remain unclear, leaving a great gap for understanding the mechanism of air pollution evolution and supporting the environment management. We estimate the annual variation using statistical methods and satellite observations at global scale from 2001 to 2016 Results show that significant variation of annual aerosol occurs over 13.6% of land areas, in which a perturbation of aerosol may cause 0.58 ± 0.45 times change in the next phase. Initial aerosol and climate influences contribute 48.4–51.6% of the total variation, respectively. Specifically, the influences of precipitation, air temperature and surface temperature represent 0.1, 18.3 and 33.2% of the total variation. Physically, the observed variation is strongly correlated with fine mode aerosols, radiative scattering and warm/hot summers in temperate and cold zones. The environmental management therefore should implement cause-oriented strategies for emission control or climatic adaption.

2014 ◽  
Vol 10 (2) ◽  
pp. 681-686 ◽  
Author(s):  
C. Hély ◽  
A.-M. Lézine ◽  
APD contributors

Abstract. Although past climate change is well documented in West Africa through instrumental records, modeling activities, and paleo-data, little is known about regional-scale ecosystem vulnerability and long-term impacts of climate on plant distribution and biodiversity. Here we use paleohydrological and paleobotanical data to discuss the relation between available surface water, monsoon rainfall and vegetation distribution in West Africa during the Holocene. The individual patterns of plant migration or community shifts in latitude are explained by differences among tolerance limits of species to rainfall amount and seasonality. Using the probability density function methodology, we show here that the widespread development of lakes, wetlands and rivers at the time of the "Green Sahara" played an additional role in forming a network of topographically defined water availability, allowing for tropical plants to migrate north from 15 to 24° N (reached ca. 9 cal ka BP). The analysis of the spatio–temporal changes in biodiversity, through both pollen occurrence and richness, shows that the core of the tropical rainbelt associated with the Intertropical Convergence Zone was centered at 15–20° N during the early Holocene wet period, with comparatively drier/more seasonal climate conditions south of 15° N.


2002 ◽  
Vol 2 ◽  
pp. 827-841 ◽  
Author(s):  
Michael Bredemeier

The focus in this review of long-term effects on forest ecosystems is on human impact. As a classification of this differentiated and complex matter, three domains of long-term effects with different scales in space and time are distinguished: 1- Exploitation and conversion history of forests in areas of extended human settlement 2- Long-range air pollution and acid deposition in industrialized regions 3- Current global loss of forests and soil degradation.There is an evident link between the first and the third point in the list. Cultivation of primary forestland — with its tremendous effects on land cover — took place in Europe many centuries ago and continued for centuries. Deforestation today is a phenomenon predominantly observed in the developing countries, yet it threatens biotic and soil resources on a global scale. Acidification of forest soils caused by long-range air pollution from anthropogenic emission sources is a regional to continental problem in industrialized parts of the world. As a result of emission reduction legislation, atmospheric acid deposition is currently on the retreat in the richer industrialized regions (e.g., Europe, U.S., Japan); however, because many other regions of the world are at present rapidly developing their polluting industries (e.g., China and India), “acid rain” will most probably remain a serious ecological problem on regional scales. It is believed to have caused considerable destabilization of forest ecosystems, adding to the strong structural and biogeochemical impacts resulting from exploitation history.Deforestation and soil degradation cause the most pressing ecological problems for the time being, at least on the global scale. In many of those regions where loss of forests and soils is now high, it may be extremely difficult or impossible to restore forest ecosystems and soil productivity. Moreover, the driving forces, which are predominantly of a demographic and socioeconomic nature, do not yet seem to be lessening in strength. It can only be hoped that a wise policy of international cooperation and shared aims can cope with this problem in the future.


2011 ◽  
Vol 16 (6) ◽  
pp. 657-684 ◽  
Author(s):  
Steven Yamarik ◽  
Sucharita Ghosh

AbstractIn this paper, we estimate the individual effects of natural openness and trade policy on air pollution. Natural openness is the component of the trade share (imports and exports as a percentage of GDP) attributable to population, geography and factor endowment differences. We find that natural openness reduces air pollution, while trade policy has a limited impact. The implication is that ‘natural’ geographic and endowment differences play a more important role than deliberate trade policy decisions in explaining the trade and environment link.


2016 ◽  
pp. 120-125
Author(s):  
N. L. Mamaeva ◽  
S. A. Petrov

In the article there were calculated near-surface concentrations of pollutants in the atmospheric air of Purovsk area, Jamal-Nenets Autonomous region. The purpose was to compare these with the maximum permissible concentration. The geo-ecological maps of dispersion of substances emissions into the air were made up using the unified program for calculating the air pollution taking into account the technical characteristics of sources and emissions themselves, natural, especially climate, conditions, as well as protection urban development activities and the lay of land. The conclusions were made about the excess in the atmosphere of maximum permissible concentration of solids on carbon monoxide in Purovsk, and on nitrogen dioxide in Purovsk, as well as in Ust-Purovsk Tazovskaya Guba permafrost areas.


2009 ◽  
Vol 37 (108) ◽  
pp. 188-217
Author(s):  
Ulrik Schmidt

Keaton and the Masses:This article explores conflicts between individual and mass and the process of massification (i.e. the becoming and unfolding of masses) as comic potential in Buster Keaton’s physical comedies. This comic potential is basically characterized by a formalized and aestheticized reduction of human individuality when confronted with objective, non-human matter. De-individualization plays an important role in modern comedy in general. With his intense focus on massification, though, Keaton is not only one of the first, but also one of the most dedicated investigators of comic de-individualization by purely physical means.The first part of the article considers the complex relations in Keaton between gag and narrative with specific regard to the conflict between the individual and the masses. Furthermore, the basic compositional elements in Keaton’s cinematographic staging of individual-mass conflicts are explored, including deactivation and isolation of the individual in relation to his immediate surroundings.Subsequently, the different forms of massification in Keaton are examined more closely with reference to variation in their comic potential. Here, Keaton’s masses are grouped into three basic forms: In the solid mass—typically materialized in heavy objects and hard surfaces—the comic potential is due to its ability to violently tumble or jam the pacified individual into de-subjectified body mass. In the fluid mass, the comic potential is basically found in the unmanageable character of the soft, formless and constantly transforming phenomenon. In pure accumulation, Keaton focuses on the comic potential of the very formation of masses as a process of accumulation (i.e., the repetitive addition of discrete, more or less identical elements). Here, Keaton’s interest lies above all in the formation of human masses (crowds).The last section considers Keaton’s cinematographic distribution of individual gags on the global scale of the entire film. Here, it is analyzed how Keaton incessantly glues the individual gags together into one large and seamlessly continuous gag. It is thus concluded that not only is each individual gag characterized by massification, but the way the different gags are interrelated throughout Keaton’s films also has a profound mass character.


2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Vijaytha Vijayakumar ◽  
A. Sabu ◽  
M. Haridas

Abstract Background The 21st century already witnessed many deadly epidemics and pandemics. The major ones were respiratory tract infections like SARS (2003), H1N1 (2009), MERS (2012) and the most recent pandemic COVID-19 (2019). The COVID-19 story begins when pneumonia of unknown cause was reported in the WHO country office of China at the end of 2019. SARS-CoV-2 is the causative agent that enters the host through the receptor ACE2, a component of the renin–angiotensin system. Main body of the abstract Symptoms of COVID-19 varies from patient to patient. It is all about the immunity and health status of the individual that decides the severity of the disease. The review focuses on the significant and often prevailing factors, those that influence the lung function. The factors that compromise the lung functions which may prepare the ground for severe COVID-19 infection are interestingly looked into. Focus was more on air pollution and cigarette smoke. Short conclusion The fact that the forested areas across the world show very low COVID-19 infection rate suggests that we are in need of the “Clean Air” on the fiftieth anniversary of World Earth Day. As many policies are implemented worldwide to protect from SARS-CoV-2, one simple remedy that we forgot was clean air can save lives. SARS-CoV-2 infects our lungs, and air pollution makes us more susceptible. In this crucial situation, the focus is only on the main threat; all other conditions are only in words to console the situation.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  

Purpose This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting-edge research and case studies. Design/methodology/approach This briefing is prepared by an independent writer who adds their own impartial comments and places the articles in context. Findings For organizational success on a global scale, companies are looking for employees who will perform above and beyond the job description. These extra-role behaviors benefit both the individual and the organization. Good strategic human resource practices (SHRPs) such as reward management (RM) and employee development (ED) can increase the potential for employees performing such organizational citizenship behaviors (OCBs). Employees who have emotional exhaustion (EE) are likely to demonstrate reduced extra-role behaviors. Managers need to ensure there are good SHRPs in place and that employee EE is reduced. Good congruence (Person-Organization fit) is beneficial for increasing OCB. Originality/value The briefing saves busy executives and researchers hours of reading time by selecting only the very best, most pertinent information and presenting it in a condensed and easy-to-digest format.


2021 ◽  
Vol 118 (46) ◽  
pp. e2103178118
Author(s):  
Teresa Jarriel ◽  
John Swartz ◽  
Paola Passalacqua

River deltas are dynamic systems whose channels can widen, narrow, migrate, avulse, and bifurcate to form new channel networks through time. With hundreds of millions of people living on these globally ubiquitous systems, it is critically important to understand and predict how delta channel networks will evolve over time. Although much work has been done to understand drivers of channel migration on the individual channel scale, a global-scale analysis of the current state of delta morphological change has not been attempted. In this study, we present a methodology for the automatic extraction of channel migration vectors from remotely sensed imagery by combining deep learning and principles from particle image velocimetry (PIV). This methodology is implemented on 48 river delta systems to create a global dataset of decadal-scale delta channel migration. By comparing delta channel migration distributions with a variety of known external forcings, we find that global patterns of channel migration can largely be reconciled with the level of fluvial forcing acting on the delta, sediment flux magnitude, and frequency of flood events. An understanding of modern rates and patterns of channel migration in river deltas is critical for successfully predicting future changes to delta systems and for informing decision makers striving for deltaic resilience.


2021 ◽  
Author(s):  
Iva Hunova ◽  
Marek Brabec ◽  
Marek Malý ◽  
Alexandru Dumitrescu ◽  
Jan Geletič

<p>Fog is a very complex phenomenon (Gultepe et al., 2007). In some areas it can contribute substantially to hydrological and chemical inputs and is therefore of high environmental relevance (Blas et al., 2010). Fog formation is affected by numerous factors, such as meteorology, air pollution, terrain (geomorphology), and land-use.</p><p>In our earlier studies we addressed the role of meteorology and air pollution on fog occurrence (Hůnová et al., 2018) and long-term trends in fog occurrence in Central Europe (Hůnová et al., 2020). This study builds on earlier model identification of year-to-year and seasonal components in fog occurrence and brings an analysis of the deformation of the above components due to the individual explanatory variables. The aim of this study was to indicate the geographical and environmental factors affecting the fog occurrence.</p><p>       We have examined the data on fog occurrence from 56 meteorological stations of various types from Romania reflecting different environments and geographical areas. We used long-term records from the 1981–2017 period. </p><p>       We considered both the individual explanatory variables and their interactions. With respect to geographical factors, we accounted for the altitude and landform. With respect to environmental factors,   we accounted for proximity of large water bodies, and proximity of forests. Geographical data from Copernicus pan-European (e.g. CORINE land cover, high resolution layers) and local (e.g. Urban Atlas) projects were used. Elevation data from EU-DEM v1.1 were source for morphometric analysis (Copernicus, 2020).</p><p>        We applied a generalized additive model, GAM (Wood, 2017; Hastie & Tibshirani, 1990) to address nonlinear trend shapes in a formalized and unified way. In particular, we employed penalized spline approach with cross-validated penalty coefficient estimation. To explore possible deformations of annual and seasonal components with various covariates of interest, we used (penalized) tensor product splines to model (two-way) interactions parsimoniously, Wood (2006).</p><p>       The fog occurrence showed significant decrease over the period under review. In general the selected explanatory variables significantly affected the fog occurrence and their effect was non-linear. Our results indicated that, the geographical and environmental variables affected primarily the seasonal component of the model. Of the factors which were accounted for, it was mainly the altitude showing the clear effect on seasonal component deformation (Hůnová et al., in press).</p><p>      </p><p> </p><p>References:</p><p>Blas, M, Polkowska, Z., Sobik, M., et al. (2010). Atmos. Res. 95, 455–469.</p><p>Copernicus Land Monitoring Service (2020). Accessed online at: https://land.copernicus.eu/.</p><p>Gultepe, I., Tardif, R., Michaelidis, S.C., Cermak, J., Bott, A. et al. (2007). Pure Appl Geophys, 164, 1121-1159.</p><p>Hastie, T.J., Tibshirani, R.J. (1990). Generalized Additive Models. Boca Raton, Chapman & Hall/CRC.</p><p>Hůnová, I., Brabec, M., Malý, M., Dumitrescu, A., Geletič, J. (in press) Sci. Total Environ. 144359.</p><p>Hůnová, I., Brabec, M., Malý, M., Valeriánová, A. (2018) Sci. Total Environ. 636, 1490–1499.</p><p>Hůnová, I., Brabec, M., Malý, M., Valeriánová, A. (2020) Sci. Total Environ. 711, 135018.</p><p>Wood, S.N. (2006) Low rank scale invariant tensor product smooths for generalized additive mixed models. Biometrics 62(4):1025-1036</p><p>Wood, S.N. (2017). Generalized Additive Models: An Introduction with R (2nd ed). Boca Raton, Chapman & Hall/CRC.</p><p> </p>


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