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Open access

Simona Condurache-Bota, Mirela Voiculescu and Carmelia Dragomir

Abstract

Climate variability is a hot topic not only for scientists and policy-makers, but also for each and every one of us. The anthropogenic activities are considered to be responsible for most climate change, however there are large uncertainties about the magnitude of effects of solar variability and other extraterrestrial influences, such as galactic cosmic rays on terrestrial climate. Clouds play an important role due to feedbacks of the radiation budget: variation of cloud cover/composition affects climate, which, in turn, affects cloud cover via atmospheric dynamics and sea temperature variations. Cloud formation and evolution are still under scientific scrutiny, since their microphysics is still not understood. Besides atmospheric dynamics and other internal climatic parameters, extraterrestrial sources of cloud cover variation are considered. One of these is the solar wind, whose effect on cloud cover might be modulated by the global atmospheric electrical circuit. Clouds height and composition, their seasonal variation and latitudinal distribution should be considered when trying to identify possible mechanisms by which solar energy is transferred to clouds. The influence of the solar wind on cloud formation can be assessed also through the ap index - the geomagnetic storm index, which can be readily connected with interplanetary magnetic field, IMF structure. This paper proposes to assess the possible relationship between both cloud cover and solar wind proxies, as the ap index, function of cloud height and composition and also through seasonal studies. The data covers almost three solar cycles (1984-2009). Mechanisms are looked for by investigating observed trends or correlation at local/seasonal scale

Open access

Carmelia Mariana Dragomir, Daniel Eduard Constantin, Mirela Voiculescu and Lucian Puiu Georgescu Georgescu

Abstract

One way of monitoring the atmospheric pollution is to estimate anthropogenic emissions. This paper presents a study of PM10 emissions in a city SE of Romania (Braila) for the period 2009-2012. PM10 emissions decrease from 304.75 t in 2009 to 78.01 t in 2012. Using data from the Environmental Protection Agency Braila and the METI-LIS dispersion model, four maps were produced in order to estimate the spatial distribution of PM10 emission in each year. Results of dispersion models show that the air quality can change abruptly between points at few meters away. Expectedly, PM10 emissions increase towards the centre of the city centre, are generally higher in the vicinity of busy streets and roads.