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This paper assesses the temporal variations of surface ozone concentrations during the period 2001–2010 in 3 regions of Spain with different geographical and socioeconomic features (northern coastland, central inland and northeast inland), as well as its link with atmospheric circulation. Specifically, daily surface atmospheric patterns over the aforementioned regions are characterized using NCEP/NCAR reanalysis data and an objective classification scheme in order to study the relationship between synoptic weather types and daily ozone levels. The results show that tropospheric ozone concentration has a tendency towards an increase during the study period, both during daytime and nighttime. Moreover, in general, this upward trend is seen throughout all of the seasons. The observed trends are in line with a reported decrease of NO X emissions and increase in surface solar radiation during the 2000s in Spain. On the other hand, interestingly, median concentrations were statistically significantly lower in days with anticyclonic weather conditions than in the rest of meteorological situations, while days with a directional weather type showed higher median levels of ozone concentration, with maximum values in days with northern and eastern component. Due to the detrimental effect that ozone has on human health, the relationship between synoptic weather patterns and daily ozone levels shown in this work could potentially be used for implementing pollution level alert protocols depending on forecast weather types. [ABSTRACT FROM AUTHOR]

This paper investigates regional sources and transport routes of Asian dust observed in Korea over the past 40 years, that is from 1965 to 2004. These long-term changes were studied in relation to climatic changes and causes. About 87% of dust events in Korea occur in the spring and have been increasing steadily since the 1980s. These trends can be attributed to regional changes in dust sources to windward and the resultant transport pathways of dust storms. This study establishes that dust events have greatly increased during the 3 years from 2000 to 2002. It may be the result of not only an eastward shift in the regional source of dust but also changes in upper-level synoptic transport patterns. Intensified atmospheric circulation and an associated increase in wind speed as well as changes in snow cover, surface wetness and potential evaporation rates throughout Inner Mongolia and Manchuria are likely to be the main causes of the steadily increasing number of dusty days in Korea. [Copyright &y& Elsevier]