Particulate Matter Mortality Rates and Their Modification by Spatial Synoptic Classification

Air pollution levels are highly correlated with temperature or humidity, so we investigated the relationship between PM10 and the spatial synoptic classification (SSC) scheme on daily mortality, according to age group and season. Daily death data for 2000–2014 from Seoul, Korea, were acquired, and time-series analysis was applied with respect to season and to each of seven distinct SSC types: dry moderate (DM); dry polar (DP); dry tropical (DT); moist moderate (MM); moist polar (MP); moist tropical (MT); and transition (T). Modification effects were estimated for daily, non-accidental, cardiovascular, and respiratory mortality between PM10 and SSC types. The following SSC-type-specific increased mortalities were observed, by cause of death: non-accidental mortality: DT (1.86%) and MT (1.86%); cardiovascular mortality: DT (2.83%) and MM (3.00%); respiratory mortality: MT (3.78%). Based on simplified weather types, increased PM10 effects in non-accidental mortality rates were observed in dry (1.54%) and moist (2.32%) conditions among those aged 40–59 years and were detected regardless of conditions in other age groups: 60–74 (1.11%), 75–84 (1.55%), and 85+ (1.75%). The effects of particulate air pollution, by SSC, suggest the applicability of SSC to the comparison and understanding of acute effects of daily mortality based on weather type.

Association between Weather Types based on the Spatial Synoptic Classification and All-Cause Mortality in Sweden, 1991–2014

Much is known about the adverse health impact of high and low temperatures. The Spatial Synoptic Classification is a useful tool for assessing weather effects on health because it considers the combined effect of meteorological factors rather than temperature only. The aim of this study was to assess the association between oppressive weather types and daily total mortality in Sweden. Time-series Poisson regression with distributed lags was used to assess the relationship between oppressive weather (Dry Polar, Dry Tropical, Moist Polar, and Moist Tropical) and daily deaths over 14 days in the extended summer (May to September), and 28 days during the extended winter (November to March), from 1991 to 2014. Days not classified as oppressive weather served as the reference category. We computed relative risks with 95% confidence intervals, adjusting for trends and seasonality. Results of the southern (Skåne and Stockholm) and northern (Jämtland and Västerbotten) locations were pooled using meta-analysis for regional-level estimates. Analyses were performed using the dlnm and mvmeta packages in R. During summer, in the South, the Moist Tropical and Dry Tropical weather types increased the mortality at lag 0 through lag 3 and lag 6, respectively. Moist Polar weather was associated with mortality at longer lags. In the North, Dry Tropical weather increased the mortality at shorter lags. During winter, in the South, Dry Polar and Moist Polar weather increased mortality from lag 6 to lag 10 and from lag 19 to lag 26, respectively. No effect of oppressive weather was found in the North. The effect of oppressive weather types in Sweden varies across seasons and regions. In the North, a small study sample reduces precision of estimates, while in the South, the effect of oppressive weather types is more evident in both seasons.

GÊNESE DAS CHUVAS EM SÃO PAULO (SP): ESTUDO COMPARATIVO ENTRE A “SPATIAL SYNOPTIC CLASSIFICATION” E A "ANÁLISE RÍTMICA EM CLIMATOLOGIA"

Trata-se de um trabalho que buscou empregar o método “Spatial Synoptic Classification” (SSC) para a região de São Paulo – SP e, por meio de um ensaio comparativo, confrontar os resultados alcançados com os da "Análise Rítmica em Climatologia" (ARC). Para tanto, o uso do método SSC possibilitou avaliar - no nível diário - tanto a atuação geral dos tipos de tempo como aquelas situações geradoras de chuvas, ao longo do período de 1958 a 2014. Do mesmo modo, dentro desse período de 57 anos, foram selecionados dois anos-padrão, um chuvoso (2010) e outro seco (2014), cujos respectivos ritmos diários (atuação geral dos sistemas atmosféricos e gênese pluvial) também foram interpretados pelo método ARC. O confronto dos resultados obtidos no emprego desses dois métodos apontou para resultados promissores e demonstrou que o método SSC é capaz de complementar a ARC. Ambos as metodologias revelaram as nítidas diferenças de ritmo quando comparadas as variações pluviais entre os dois anos analisados, sobretudo durante o verão. Tais métodos trouxeram à luz, ainda, os tipos de tempo geradores de grandes volumes de chuva no verão de 2010 e as sequências rítmicas responsáveis pela longa e severa estiagem que ocorreu na metrópole paulistana durante o ano de 2014.