Changes In Air Pollution Levels Research Articles

Alleviation of PM2.5-associated Risk of Daily Influenza Hospitalization by COVID-19 Lockdown Measures: A Time-series Study in Northeastern Thailand.

Abrupt changes in air pollution levels associated with the coronavirus disease 2019 (COVID-19) outbreak present a unique opportunity to evaluate the effects of air pollution on influenza risk, at a time when emission sources were less active and personal hygiene practices were more rigorous. This time-series study examined the relationship between influenza cases (n=22 874) and air pollutant concentrations from 2018 to 2021, comparing the timeframes before and during the COVID-19 pandemic in and around Thailand's Khon Kaen province. Poisson generalized additive modeling was employed to estimate the relative risk of hospitalization for influenza associated with air pollutant levels. Before the COVID-19 outbreak, both the average daily number of influenza hospitalizations and particulate matter with an aerodynamic diameter of 2.5 μm or less (PM2.5) concentration exceeded those later observed during the pandemic (p<0.001). In single-pollutant models, a 10 μg/m3 increase in PM2.5 before COVID-19 was significantly associated with increased influenza risk upon exposure to cumulative-day lags, specifically lags 0-5 and 0-6 (p<0.01). After adjustment for co-pollutants, PM2.5 demonstrated the strongest effects at lags 0 and 4, with elevated risk found across all cumulative-day lags (0-1, 0-2, 0-3, 0-4, 0-5, and 0-6) and significantly greater risk in the winter and summer at lag 0-5 (p<0.01). However, the PM2.5 level was not significantly associated with influenza risk during the COVID-19 outbreak. Lockdown measures implemented during the COVID-19 pandemic could mitigate the risk of PM2.5-induced influenza. Effective regulatory actions in the context of COVID-19 may decrease PM2.5 emissions and improve hygiene practices, thereby reducing influenza hospitalizations.

Spatio-temporal analysis of air pollution dynamics over Bangalore city during second wave of COVID-19

The country wide lockdown implemented during 27th April to 14th June 2021 in order to prevent the spread of COVID-19 during the second wave in India. Effect of the restricted lockdown resulted in improved air quality. This study focuses on analyzing the spatio-temporal distribution analysis of major air pollutant concentration over Bangalore city in India. The inverse distance weighting (IDW) method is implemented for the spatial analysis in order to quantify the distribution of the pollutant concentrations at each location in the Urban city of Bangalore. The research considers the distinct periods of pre-lockdown and lockdown during the second wave of COVID-19 pandemic in 2021 to investigate the impact of reduced human activities on air quality over the city. The study mainly utilizes the air pollution data collected from Central Pollution Control Board (CPCB) monitoring stations across Bangalore, including measurements of pollutants such as PM2.5, PM10, O3, NO2, SO2, and CO. The IDW method is implemented to create the high-resolution pollution concentration maps for both the pre-lockdown and lockdown periods. This spatial distribution provides valuable insights into the variations in the pollution levels though out the Bangalore city. The comparative analysis of the concentration maps reveals significant changes in air pollution levels between the two periods; similarly, the temporal weekly average analysis also witnessed negative anomalies during the lockdown weeks. The results indicate substantial reductions in pollutant concentrations during the second wave COVID-19 lockdown, attributed to decreased vehicular emissions, industrial activities, and construction operations. The pre-lockdown period serves as a baseline for assessing the improvements in air quality during the lockdown. The spatio-temporal modeling approach enhances our understanding of the distribution patterns of air pollutants across the Bangalore metropolitan city. The findings underscore the potential benefits of implementing sustainable strategies to maintain improved air quality even after the pandemic subsides.

Role of garbage classification in air pollution improvement of a municipal solid waste disposal base

Assessing the impact of garbage classification on air pollution in rapidly developing economic regions is particularly necessary in light of the current policy trends. We evaluated the resulting changes in air pollution levels before and after garbage classification based on a three-year field observation using high-resolution online instruments in a municipal solid waste comprehensive disposal base. A targeted scheme is proposed to analyze the variation characteristics of major sources in a complex multi-source environment (Environments with multiple sources of pollution). We found that the concentrations of hydrogen sulfide (H2S) and volatile organic compounds (VOCs) in ambient air decreased by 48% and 43% respectively after garbage classification, and their spike frequency was controlled at approximately 0.01. The average H2S and VOC concentrations were generally low during the daytime, but relatively high during the nighttime because of meteorology and photochemistry. The ozone formation potential of the base decreased by 56%. Alternatively, emissions from transportation and combustion sources increased, while landfill pollution decreased owing to changes in the method of waste disposal. This finding suggests that garbage classification is an effective means of improving the air quality. This new scheme has a good potential in actual research scenarios.

Monitoring the impact of the COVID-19 lockdown on air quality in Lanzhou: Implications for future control strategies

China implemented a one-month lockdown after the 2020 Spring Festival to prevent the spread of COVID-19. The closure measures provide a rare opportunity to understand the resulting changes in air pollution levels and to test the effectiveness of previous environmental protection measures. We used the time series decomposition method to quantify the air pollution in Lanzhou during the closure period. The results showed that during the epidemic lockdown period, although the concentration of SO2 in Lanzhou decreased substantially, there was a significant increase in the concentration of O3 (by 19.14%), followed by a gradual return to the normal level. Most of the changes during the COVID-19 lockdown were within the range of fluctuations over the past five years. The trend of decreasing SO2 and CO in 2020 was less than that during 2015–2019, and the continuous decline of the PM10 concentration exceeded expectations. NO2, PM2.5 and O3 maintained the trend of the previous five years. Our results show that temporary social closure measures have a limited effect on improving air quality in Lanzhou, and they emphasize the importance of reducing the O3 concentration in the future.

Demographic and Psychosocial Characteristics, Air Pollution Exposure, and Housing Mobility of Mexican Immigrant Families.

People of color and lower socioeconomic status groups in the USA, including those of Mexican origin, are exposed to higher concentrations of air pollution, including fine particulate matter (PM2.5). Associations were examined between neighborhood air pollution levels and the psychosocial and demographic characteristics of linguistically isolated Mexican-origin immigrant families. Housing mobility and changes in air pollution levels due to changes in residence were also examined. A sample of 604 linguistically isolated Mexican-origin families in central TX provided data on demographic and psychosocial experiences. Outdoor air pollution concentrations at participants' home addresses were based on high-resolution estimates of fine particulate matter (PM2.5) and its constituents. Movers were identified as families whose residential addresses changed during the study period; these participants were further grouped and compared based on the change in their residential PM2.5 concentration from before to after their move. Lower PM2.5 concentrations were associated with reports of more ethnic discriminatory experiences, higher socioeconomic status, and higher perceived neighborhood safety. Among the 23% of families who changed residences, PM2.5 concentrations were generally lower at the new family address. Families with mothers reporting a greater sense of neighborhood safety or acculturation levels tended to move from one area low in air pollutants to another, and mothers reporting the lowest levels of neighborhood safety or acculturation tended to move from one area high in air pollutants to another. There are limits to assimilation for Mexican immigrant families. Living in more advantaged neighborhoods is associated with experiencing better air quality, but this advantage may come at the cost of experiencing more ethnic discrimination.

Impactar Tool: Valuing Air Quality Health Impacts of Urban Bus Fleet Changes in Brazil (2022)

In Brazil, where the transport sector is one of the biggest contributors to air pollution in cities, replacing conventional buses with electric vehicles can save lives and positively impact the economy. This is what ImpactAr tool, a technical note and a valuation model, demonstrates. Developed in partnership with the Children’s Investment Fund Foundation (CIFF), ImpactAr provides the magnitude of the variations on the number of fatalities and hospitalizations and the consequent economic and welfare costs related to changes in air pollution levels caused by modifications in the Brazilian urban bus fleets. The methodology can be applied by any city, sector operators, academics and researchers. For São Paulo, Rio de Janeiro, Belo Horizonte and Niterói, spreadsheets are already set up with data for environmental, epidemiological and economic projections. By making the implicit impacts on health and well-being of air pollution visible, ImpactAr can encourage cities to initiate or accelerate the transition from public transport to green fleets.

Air Pollution Mediates the Association between Human Mobility and COVID-19 Infection

The effects of the restriction policies on human mobility and on the prevention of SARS-CoV-2 (coronavirus disease 2019 (COVID-19) transmission were reported. The efficiency of human mobility restriction due to the social distancing measures of cities on preventing SARS-CoV-2 spread remains unclear. The objective of this study was to investigate the mediating effects of air pollution on the association between human mobility and daily confirmed COVID-19 cases. Daily mobility data (i.e., walking, driving, and using public transport), air pollutants, and confirmed COVID-19 cases were collected in Taiwan during 1 to 30 May 2021. Associations of air pollution with 7-day-lag confirmed COVID-19 cases and with mobility were examined by linear regression models, while the mediating effects were assessed using a PROCESS analysis. We observed that an increase in air pollution was associated with an increase in confirmed COVID-19 cases (p < 0.05). We found that 1 min spent on mobility was associated with changes in air pollution levels (p < 0.05). We observed that levels of particulate matter with an aerodynamic diameter of < 10 µm (PM10), PM2.5, NO2, and CO mediated associations of walking, driving, and using public transport with confirmed COVID-19 cases (p < 0.05). Our findings suggest that the nationwide restrictions (social distancing measures) may reduce human mobility and activities, which was associated with a decrease in confirmed COVID-19 cases due to the mediating effects of air pollution. Reductions in human mobility and air pollution could be effective measures for controlling COVID-19 transmission.

Change Points Detection and Trend Analysis to Characterize Changes in Meteorologically Normalized Air Pollutant Concentrations

Identifying changes in ambient air pollution levels and establishing causation is a research area of strategic importance to assess the effectiveness of air quality interventions. A major challenge in pursuing these objectives is represented by the confounding effects of the meteorological conditions which easily mask or emphasize changes in pollutants concentrations. In this study, a methodological procedure to analyze changes in pollutants concentrations levels after accounting for changes in meteorology over time was developed. The procedure integrated several statistical tools, such as the change points detection and trend analysis that are applied to the pollutants concentrations meteorologically normalized using a machine learning model. Data of air pollutants and meteorological parameters, collected over the period 2013–2019 in a rural area affected by anthropic emissive sources, were used to test the procedure. The joint analysis of the obtained results with the available metadata allowed providing plausible explanations of the observed air pollutants behavior. Consequently, the procedure appears promising in elucidating those changes in the air pollutant levels not easily identifiable in the original data, supplying valuable information to identify an atmospheric response after an intervention or an unplanned event.

Inflammatory and oxidative stress responses of healthy elders to solar-assisted large-scale cleaning system (SALSCS) and changes in ambient air pollution: A quasi-interventional study in Xi'an, China

An outdoor solar assisted large-scale cleaning system (SALSCS) was constructed to mitigate the levels of fine particulate matter (PM2.5) in urban areas of Xi'an China, providing a quasi-experimental opportunity to examine the biologic responses to the changes in pollution level. We conducted this outdoor SALSCS based real-world quasi-interventional study to examine the associations of the SALSCS intervention and changes in air pollution levels with the biomarkers of systemic inflammation and oxidative stress in healthy elders. We measured the levels of 8-hydrox-2-deoxyguanosine (8-OHdG), Interlukin-6 (IL-6), as well as tumor necrosis factor alpha (TNF-α) from urine samples, and IL-6 from saliva samples of 123 healthy retired participants from interventional/control residential areas in two sampling campaigns. We collected daily 24-h PM2.5 samples in two residential areas during the study periods using mini-volume samplers. Data on PM10, gaseous pollutants and weather factors were collected from the nearest national air quality monitoring stations. We used linear mixed-effect models to examine the percent change in each biomarker associated with the SALSCS intervention and air pollution levels, after adjusting for time trend, seasonality, weather factors and personal characteristics. Results showed that the SALSCS intervention was significantly associated with decreases in the geometric mean of biomarkers by 47.6% (95% confidence interval: 16.5–67.2%) for 8-OHdG, 66% (31.0–83.3%) for TNF-α, 41.7% (0.2–65.9%) and 43.4% (13.6–62.9%) for urinary and salivary IL-6, respectively. An inter-quartile range increase of ambient PM2.5 exposure averaged on the day of the collection of bio-samples and the day before (34.1 μg/m3) was associated, albeit non-significantly so, with 22.8%–37.9% increases in the geometric mean of these biomarkers. This study demonstrated that the SALSCS intervention and decreased ambient air pollution exposure results in lower burden of systemic inflammation and oxidative stress in older adults.

Differential Effects of the COVID-19 Lockdown and Regional Fire on the Air Quality of Medellín, Colombia

Governments’ responses to the COVID-19 pandemic provide a unique opportunity to study the effects of restricted socioeconomic activity on air quality. Here, we study the changes in air pollution levels during the lockdown in Medellín and its metropolitan area, Colombia, for periods with and without enhanced regional fire activity, considering the effects of meteorology using random forest and multiple linear regression methods. The lockdown measures, which reduced mean traffic volume by 70% compared to 2016–2019, resulted in reductions for PM2.5 (50–63%), PM10 (59–64%), NO (75–76%), NO2 (43–47%), and CO (40–47%), while O3 concentration increased by 19–22%. In contrast, when fire activity was high, the effects of the lockdown on air quality were shadowed by the long-range transport of biomass burning emissions, increasing fine particulate matter and ozone. This study shows that healthier levels are achievable through significant efforts from decision-makers and society. The results highlight the need to develop integral measures that do not only consider reductions in the local emissions from transportation and industry, but also the role of fire activity in the region, as well as the difficulties of achieving reductions in ozone from measures that are effective at reducing primary pollutants.

Unprecedented reduction in air pollution and corresponding short-term premature mortality associated with COVID-19 lockdown in Delhi, India

ABSTRACT Countries around the world introduced strict restrictions on movement and activities known as ‘lockdowns’ to restrict the spread of the novel coronavirus disease (COVID-19) from the end of 2019. A sudden improvement in air quality was observed globally as a result of these lockdowns. To provide insight into the changes in air pollution levels in response to the COVID-19 restrictions we have compared surface air quality data in Delhi during four phases of lockdown and the first phase of the restriction easing period (25 March to 30 June 2020) with data from a baseline period (2018–2019). Simultaneously, short-term exposure of PM2.5 and O3 attributed premature mortality were calculated to understand the health benefit of the change in air quality. Ground–level observations in Delhi showed that concentrations of PM10, PM2.5 and NO2 dropped substantially in 2020 during the overall study period compared with the same period in previous years, with average reductions of ~49%, ~39%, and ~39%, respectively. An overall lower reduction in O3 of ~19% was observed for Delhi. A slight increase in O3 was found in Delhi’s industrial and traffic regions. The highest peak of the diurnal variation decreased substantially for all the pollutants at every phase. The decrease in PM2.5 and O3 concentrations in 2020, prevented 904 total premature deaths, a 60% improvement when compared to the figures for 2018–2019. The restrictions on human activities during the lockdown have reduced anthropogenic emissions and subsequently improved air quality and human health in one of the most polluted cities in the world. Implications: I am submitting herewith the manuscript entitled “Unprecedented Reduction in Air Pollution and Corresponding Short-term Premature Mortality Associated with COVID-19 Forced Confinement in Delhi, India” for potential publishing in your journal. The novelty of this research lies in: (1) we utilized ground-level air quality data in Delhi during four phases of lockdown and the first phase of unlocking period (25th March to 30th June) for 2020 as well as data from the baseline period (2018–2019) to provide an early insight into the changes in air pollution levels in response to the COVID-19 pandemic, (2) Chatarize the change of diurnal variation of the pollutants and (3) we assess the health risk due to PM2.5 and O3. Results from ground-level observations in Delhi showed that concentrations of PM10, PM2.5 and NO2 substantially dropped in 2020 during the overall study period compared to the similar period in previous years, with an average reduction of ~49%, ~39%, and ~39%, respectively. In the case of O3, the overall reduction was observed as ~19% in Delhi, while a slight increase was found in industrial and traffic regions. And consequently, the highest peak of the diurnal variation decreased substantially for all the pollutants. The health impact assessment of the changes in air quality indicated that 904 short-term premature deaths (~60%) were prevented due to the decline in PM2.5 and O3 concentrations in the study period. The restrictions on human activities during the lockdown have reduced the anthropogenic emissions and subsequently improved air quality and human health in one of the most polluted cities in the world.

Urban Air Quality Guidance Based on Measures Categorization in Road Transport

Air pollution is a cause for serious concerns in urban areas in Republic of North Macedonia. Intensive development of road transport increases the main air pollutants’ concentrations - particulate matter and nitrogen dioxide, whose monitored values are continuously exceeding the limit. The main disadvantage of the national plans and annual reports is the absence of comprehensive and categorized list of reduction/mitigation measures for road transport impacts on air quality. Analyzing the current air pollution problem and road transport contribution this paper provides the needed and detailed categorization of short-to-long term reduction/mitigation measures consisting of five subcategories. Based on measure categorization, a guiding frame for urban air quality is designed, intended for further support and assistance for local authorities in the process of air pollution control. Designed with integrated activities, the air quality guidance enables them to select suitable measures to manage road transport pollution and to evaluate their effects estimating the changes in air pollution levels. Hence, the guidance can be used for thorough planning of air quality issues caused by road transport and for policy making. Contributing for urban air quality improvement the guidance is a first step towards the implementation of air pollution management in urban areas. Doi: 10.28991/cej-2021-03091651 Full Text: PDF

Four-Month Changes in Air Quality during and after the COVID-19 Lockdown in Six Megacities in China.

The pandemic of coronavirus disease 2019 (COVID-19) resulted in a stringent lockdown in China to reduce the infection rate. We adopted a machine learning technique to analyze the air quality impacts of the COVID-19 lockdown from January to April 2020 for six megacities with different lockdown durations. Compared with the scenario without lockdowns, we estimated that the lockdown reduced ambient NO2 concentrations by 36–53% during the most restrictive periods, which involved Level-1 public health emergency response control actions. Several cities lifted the Level-1 control actions during February and March, and the avoided NO2 concentrations subsequently dropped below 10% in late April. Traffic analysis during the same periods in Beijing and Chengdu confirmed that traffic emission changes were a major factor in the substantial NO2 reduction, but they were also associated with increased O3 concentrations. The lockdown also reduced PM2.5 concentrations, although heavy pollution episodes occurred on certain days due to the enhanced formation of secondary aerosols in association with the increased atmospheric oxidizing capacity. We also observed that the changes in air pollution levels decreased as the lockdown was gradually eased in various cities.

Changes in air pollution levels after COVID-19 outbreak in Korea

In order to control the spread of COVID-19, social distancing measures were implemented in many countries. This study investigated changes in air pollution during the social distancing after the COVID-19 outbreak in Korea. Ambient PM2.5, PM10, NO2, and CO that are particularly related to industrial activities and traffic were reduced during the social distancing in response to the COVID-19 outbreak. In March 2020, immediately after social distancing, mean levels of PM2.5, PM10, NO2, and CO decreased nationwide from last year's mean levels by 16.98 μg/m3, 21.61 μg/m3, 4.16 ppb, and 0.09 ppm, respectively (p-value for the year-to-year difference <0.001, =0.001, =0.008, <0.001), a decrease by 45.45%, 35.56%, 20.41%, and 17.33%, respectively. Changes in ambient O3 or SO2 were not observed to be attributable to social distancing. Our findings, that such effort for a short period of time resulted in a significant reduction in air pollution, may point toward reducing air pollution as a public health problem in a more sustainable post-COVID-19 world.

Short-term associations between ambient air pollution and acute atrial fibrillation episodes

IntroductionAtrial fibrillation (AF), prevalent in approximately 1–3% of the population, is associated with a higher risk of stroke, dementia, mortality, and a reduced quality of life. Air pollution may be associated with heart rhythm disturbances, but there is limited evidence regarding whether short-term changes in air pollution levels are associated with acute onset of AF episodes. MethodsWe screened 8,899 randomly selected 75-yearolds living in Stockholm without previously known AF for AF using home-based short-term ambulatory 1-lead ECG-measurements 2–4 times a day for 14 days. Screenings were carried out in 2012–2013 and 2016–2018. We used generalized estimating equations to quantify the association between PM2.5, PM10, NO2 and O3 obtained from a fixed monitoring station and risk of AF onset among participants with AF observed during the screening period, adjusting for temperature, relative humidity and temporal factors. We explored potential susceptible subgroups. ResultsAmong 218 participants with 469 AF episodes we observed higher odds of AF following higher 24-hour mean levels of PM10 and O3, reaching statistical significance for PM10 levels averaged over the previous 12–24-hours [OR 1.10 (95%CI 1.01–1.19) per IQR of PM10 (7.8 µg/m3)]. In subgroup analyses, PM2.5 was more strongly associated with AF among participants with hypertension and PM10 and O3 were more strongly associated with AF among participants with diabetes and overweight. ConclusionThese results suggest that in an urban setting with relatively low levels of ambient air pollution, hourly changes in pollutant levels may increase the risk of acute episodes of both asymptomatic and symptomatic AF, especially among people with diabetes, hypertension or overweight.

Changes in air quality during the lockdown in Barcelona (Spain) one month into the SARS-CoV-2 epidemic

Lockdown measures came into force in Spain from March 14th, two weeks after the start of the SARS-CoV-2 epidemic, to reduce the epidemic curve. Our study aims to describe changes in air pollution levels during the lockdown measures in the city of Barcelona (NE Spain), by studying the time evolution of atmospheric pollutants recorded at the urban background and traffic air quality monitoring stations. After two weeks of lockdown, urban air pollution markedly decreased but with substantial differences among pollutants. The most significant reduction was estimated for BC and NO2 (−45 to −51%), pollutants mainly related to traffic emissions. A lower reduction was observed for PM10 (−28 to −31.0%). By contrast, O3 levels increased (+33 to +57% of the 8 h daily maxima), probably due to lower titration of O3 by NO and the decrease of NOx in a VOC-limited environment. Relevant differences in the meteorology of these two periods were also evidenced. The low reduction for PM10 is probably related to a significant regional contribution and the prevailing secondary origin of fine aerosols, but an in-depth evaluation has to be carried out to interpret this lower decrease. There is no defined trend for the low SO2 levels, probably due to the preferential reduction in emissions from the least polluting ships. A reduction of most pollutants to minimal concentrations are expected for the forthcoming weeks because of the more restrictive actions implemented for a total lockdown, which entered into force on March 30th. There are still open questions on why PM10 levels were much less reduced than BC and NO2 and on what is the proportion of the abatement of pollution directly related to the lockdown, without meteorological interferences.

Research on the Impact of Air Pollution on the Real Estate Market-Take Shanghai’s Residential Commercial Housing Market as an Example

Based on urban economics, behavioural economics and western economics theory, we analysed the effects of air pollution on the real estate market through VAR model and IRF using the AQI and the residential commercial housing market data from January 1, 2015 to June 30, 2020. We found that there is intrinsic link between changes in air pollution levels and changes in real estate market. When air pollution levels increase, it will have a sustained inhibitory effect on housing price and housing turnover. The effect on housing price will last about 5 months and the effect on housing turnover will last about 2 months. After having a comparative analysis of the IRF of the average price in six jurisdictions in Shanghai we found that inhibitory effect which air pollution impact on real estate market has different forms of expression. Residents in areas with relatively poor air quality are more willing to pay for clean air and housing transactions in areas with relatively good air quality are more sensitive to air pollution.

Estimating the Health and Economic Impacts of Changes in Local Air Quality.

To demonstrate the benefits-mapping software Environmental Benefits Mapping and Analysis Program-Community Edition (BenMAP-CE), which integrates local air quality data with previously published concentration-response and health-economic valuation functions to estimate the health effects of changes in air pollution levels and their economic consequences. We illustrate a local health impact assessment of ozone changes in the 10-county nonattainment area of the Dallas-Fort Worth region of Texas, estimating the short-term effects on mortality predicted by 2 scenarios for 3 years (2008, 2011, and 2013): an incremental rollback of the daily 8-hour maximum ozone levels of all area monitors by 10 parts per billion and a rollback-to-a-standard ambient level of 65 parts per billion at only monitors above that level. Estimates of preventable premature deaths attributable to ozone air pollution obtained by the incremental rollback method varied little by year, whereas those obtained by the rollback-to-a-standard method varied by year and were sensitive to the choice of ordinality and the use of preloaded or imported data. BenMAP-CE allows local and regional public health analysts to generate timely, evidence-based estimates of the health impacts and economic consequences of potential policy options in their communities.

ANALYSIS AND ASSESSMENT OF THE AIR POLLUTION LEVEL OF KHARKIV

Purpose.Analysis and assessment of the Kharkov atmospheric air in the period 2010-2015 based on annual observations of air pollution. Methods.Theoretical analysis and synthesis.Results.The estimation of the ecological state of atmospheric air in the city of Kharkiv. Based on the analysis of theresults of observations of the Kharkiv Regional Center for Hydrometeorology investigated the dynamics of changes in air pollution levels during the 2010-2015 gg. The list of main pollutants (formaldehyde, dust, carbon monoxide, soot, phenol, nitrogen dioxide) and the contribution of each of them in the general level of air pollution. The comparative analysis of the level of air pollution in different parts of the city.Conclusions. Air quality in a scale pollution index meets the evaluation "slightly polluted". Maximum air pollution in the Shevchenko district,Kharkov. To improve air quality in the priority should be regarded as a set of measures to reduce emissions from road transport as a major source of air pollution.

Decadal changes in radiative fluxes at land and ocean surfaces and their relevance for global warming

Anthropogenic interference with climate occurs primarily through modification of radiative fluxes in the climate system. Increasing releases of greenhouse gases into the atmosphere lead to an enhancement of thermal radiation from the atmosphere to the surface by presently about 2 W m−2 per decade, thereby causing global warming. Yet not only thermal radiation undergoes substantial decadal changes at the Earth surface, but also incident solar radiation (SSR), often in line with changes in aerosol emissions. Land‐based observations suggest widespread declines in SSR from 1950s to 1980s (‘global dimming’), a partial recovery (‘brightening’) since mid‐1980s, and indication for an ‘early’ brightening in 1930s and 1940s. No similar extended observational records are available over oceans. However, modeling studies, conceptual frameworks and available satellite‐derived records point to the existence of decadal SSR variations also over oceans. SSR changes overall match with decadal variations in observed warming rates, suggesting that SSR variations may effectively modulate greenhouse gas‐induced warming. Specifically, on the Northern Hemisphere, the lack of warming from 1950s to 1980s and its subsequent acceleration in the 1990s fits to the trend reversal from dimming to brightening and associated changes in air pollution levels. From the 1950s to 1980s no warming was also observed over Northern Hemispheric Oceans, in line with conceptual ideas that subtle aerosol changes in pristine ocean areas, effectively amplified by aerosol–cloud interactions, can substantially alter SSR, thereby modulating Sea Surface Temperatures. On the Southern Hemisphere, the absence of significant aerosol levels fits to the observed stable (greenhouse gas‐induced) warming rates since the 1950s. WIREs Clim Change 2016, 7:91–107. doi: 10.1002/wcc.372This article is categorized under: Paleoclimates and Current Trends &gt; Modern Climate Change