Elvira Kovač-Andrić

Impact of meteorological factors on ozone concentrations modelled by time series analysis and multivariate statistical methods

Abstract The ozone concentrations in Slavonia (eastern part of Croatia) were measured for the first time in spring–summer season 2002. Fourier analysis, principal components analysis (PCA) and multiple linear regression analysis (MLR) were applied to these time series. Weekday effect in spring and weekend effect in summer period were observed. Correlation with meteorological parameters is strongly emphasized from 10xa0a.m.–3xa0p.m. MLR models showed that variations in ozone concentrations are attributed to variation of few meteorological parameters with R2xa0≈xa00.7 and 0.8 in the spring and summer, respectively.

Photochemical pollution indicators— an analysis of 12 European monitoring stations

Indicators were devised to classify air pollution monitoring sites according to the type of expected photochemical pollution. The indicators are based on measured ozone volume fractions, the most frequently monitored component of photochemical pollution, and in particular on two contributions: one due to the ratio of daily maximum-to-minimum ozone volume fractions and the other to observed peak values. The two contributions regarded as independent are logically connected by “and” and therefore mathematically combined by multiplication. The criterion of classification is mainly described by the mentioned ratio and incidences of ozone volume fractions exceeding the limit of 80xa0ppb. Twelve monitoring stations within the European network (Cooperative programme for monitoring and evaluation of long-range transmission of air pollutants in Europe, EMEP) were classified according to this indicator predicting what ozone levels can be expected at the particular sites during the growth season (April through September) into three groups: clean, medium, and polluted, based on the data for the 7xa0years (1997 to 2003).

Temporal Variations in Concentrations of Ozone, Nitrogen Dioxide, and Carbon Monoxide at Osijek, Croatia

The purpose of this study was to investigate the ozone, carbon monoxide, and nitrogen dioxide variations and their correlation with meteorological parameters in Osijek (Eastern Croatia) during the summer seasons of 2002, 2007, and 2012. The measured data are discussed in relation to the EU guidelines (Directive 2002/3/EC, Directive 2008/50/EC). In order to characterize ambient air with respect to ozone photochemical pollution we calculated three photochemical pollution indicators. These indicators may also be a valid measure for harmful effects on living organisms. The influence of local meteorological parameters on the measured concentrations of ozone, carbon monoxide, and nitrogen dioxide was also investigated. We have attempted to establish correlations between measured pollutant concentrations and meteorological parameters using the technique of multivariate principal component analysis (PCA).

Assessment of ozone variations and meteorological influences in a tourist and health resort area on the island of Mali Lošinj (Croatia).

The purpose of this study was to investigate ozone, variations, and its correlation with meteorological parameters at a remote location on the Mali Lošinj Island, which has been a tourist and health resort area in the northern Adriatic. The measured data are discussed in relation to the EU guidelines (Directive 2002/3/EC; Directive 2008/50/EC). In order to characterize ambient air with respect to ozone vegetation injury and photochemical pollution, we calculated accumulated dose over a threshold of 40 parts per billion index and two photochemical pollution indicators. The influence of local meteorological parameters on the measured ozone volume fractions was also investigated. We used the multivariate technique principal component analysis to trace correlations between measured ozone concentration and meteorological parameters.

CONDIÇÕES CLIMÁTICAS E O RISCO DE EXACERBAÇÃO DA ASMA

Objetivo: Foi investigada a associacao entre diferencas horarias da poluicao do ar e exacerbacao da asma em Campo Grande, usando dados relacionados com internacoes por asma e verificada a sazonalidade e status socioeconomico com uma resolucao temporal horaria. Metodologia : Foi aplicado caso de cruzamento estratificada ajustado para o tempo; o atraso foi estratificado com 1 e 6, 7 e 12, 13 e 18, 19 e 24, 25 e 48, e 49 e 72 hs; (95% intervalo de confianca), o aumento do intervalo interquartil foi apos 19 e 24xa0 para O 3 . Resultados: O efeito foi de lag 25 e 48 h no inverno para o ozonio (O 3) . Os efeitos para o O 3 foram para a idade de baixo estatus socioeconomico modificado em lag 7e12 h (1,252 (1.04 e 1.51)). O O 3 aumentou o risco de exacerbacao da asma. Niveis mais altos de O 3 foram associados com risco aumentado de exposicao das exacerbacoes da asma. Conclusao : Os efeitos adversos da estacao do ano do O 3 foram modificados por idade. Os resultados indicam que a politica de saude no municipio deve se concentrar nas populacoes vulneraveis, como portadores de asma. Descritores : Poluicao do Ar; Asma; Risco.

IMPACTO DE FATORES METEOROLÓGICOS SOBRE AS CONCENTRAÇÕES DE OZÔNIO MODELADOS POR ANÁLISE DE SÉRIES TEMPORAIS E MÉTODOS ESTATÍSTICOS MULTIVARIADOS

O objetivo desta pesquisa foi de desenvolver um modelo para prever as concentracoes de ozonio em funcao das variaveis climaticas. As medidas de concentracao do ozonio foram realizadas na Universidade Federal de Mato Grosso do Sul, utilizando dados do periodo de janeiro a dezembro de 2014. As variaveis preditoras referentes ao clima (umidade relativa, velocidade do vento, chuva, aeerossois, indice de claridade, radiacao solar global e temperatura) foram cedidas pela CEMTEC-Campo Grande-MS. Foram realizadas analise de componentes principais (PCA) e analise de regressao linear multipla (MLR) aplicadas a estas series temporais. As principais relacoes observadas nestas analises foram entao usadas para obter uma equacao de regressao que liga as concentracoes de ozonio diurnas com parâmetros climaticos. O modelo desenvolvido e capaz de explicar 99% da variabilidade nas concentracoes de ozonio de superficie com um erro de 0,2%

Assessment of Ozone Variations and Meteorological Influences in West Center of Brazil, from 2004 to 2010

The study of the time series from the township of Campo Grande in the State of Mato Grosso do Sul (from January 2004 to 31 December 2010) is presented. Various statistical methods were used for the data analysis. Using robust statistics, very pronounced skewness of the ozone volume part distribution during each month of the year was obtained. The variability in data is the largest during a month of September. The average annual values have asymmetrical distribution of the ozone volume fraction. Within the measured period, these averages are between 15 and 20xa0ppb. Particularly pronounced ozone distribution asymmetry throughout the year 2007 could be explained by observing meteorological parameters. Principal component analysis (PCA) presented here clearly shows that air temperature and wind speed are contributing factors in ozone formation, while relative humidity and atmospheric pressure cause the decrease in the ozone volume fraction in the air. Further, the hierarchical cluster analysis (CA) was performed for meteorological and ozone data using the Ward’s methods. The correlation between ozone and the effective temperature index (TEv) showed a development of the ozone with high temperature of air. From the Pearson’s correlation coefficients, it is clear that the relative humidity and the air temperature have a negative effect on respiratory system, causing respiratory illnesses.