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  • Author: Lucian Sfîcă x
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Lucian Sfîcă, Pavel Ichim, Liviu Apostol and Ovidiu Machidon

Abstract

This study is based on 3 years of hourly observations of global solar radiation (2014-2016), at a new weather station installed in the region of Central Moldavian Plateau, at Mădârjac (47.05°N, 27.25°E, 270 m). The main characteristics of annual, monthly and daily regime of global radiation were emphasized using for comparison similar data from Iașioficial weather station. Smaller annual amount of global solar radiation than those observed in previous studies were observed, reaching 4734 MJ/m2 in Iași and 4454 MJ/m2 in Mădârjac. An altidudinal gradient of global solar radiation close to 140 MJ/m2 was identified for the hilly region of Moldova. Despite the overall higher values in Iași, 30% of days indicates higher values of this parameter at Mădârjac weather station. These results can be used for the evaluation of the photo-voltaic potential in the region, but also to understand the altitudinal differences of solar radiation in the hilly region in Moldavia, since the only long-range actinometric stations from this part of Romania, Iași and Galați, are located at low altitudes.

Open access

Emanuel Ștefan Baltag, Viorel Pocora, Constantin Ion and Lucian Sfîcă

Abstract

Long-legged Buzzard (Buteo rufinus) is a medium sized bird of prey which is known as a breeding species for Romania. In the last years it started to become a common wintering presence in the south-eastern part of Romania (Dobrogea) but it was also recorded in the more northern areas (Moldova) during the cold season. Its presence in Moldova, during the winter period, was recorded in large river valleys, with agricultural lands or grasslands and with trees or timber poles, which are used for perching. Long-legged Buzzard is a new presence for Moldavian winter seasons and it could be observed only in warm periods of winter, when the daily mean temperature is above 0°C. The wintering places are maintained not only for all winter period, but also for the next years. This behaviour could be explained by its territorial fidelity, which was recorded also in other European buzzard species during the winter period.

Open access

Pavel Ichim, Liviu Apostol, Lucian Sfîcă, Adriana-Lucia Kadhim-Abid and Vasilică Istrate

Abstract

Temperature inversions represent complex phenomena, specific for depression forms of relief which introduce changes in vertical zoning (Apăvăloae, Apostle, Pîrvulescu, 1986 by stable air stratification (Erhan, 1981), because of their morphological features, this is due to the interdependence of general movement and characteristics of the active surface, being the cause of their production (Apăvăloae, et. al., 1984, 1986, 1987). The generation of thermal inversions, their intensity and frequency is a consequence of altitude topography, morphology, fragmentation, orientation and degree of closure to external drives. (Apăvăloae, Apostle, Pîrvulescu, 1988). Thermal inversions represent complex phenomena, specific to depression landforms that introduce changes within the vertical zoning (Apăvăloae, Apostol, Pîrvulescu, 1986) by stable air stratification (Matveev, 1958, Erhan, 1981, Yinghui Liu, 2002) where vertical thermal gradient is negative (Matveev, 1958), due to their morphological features, also as a consequence of the interdependance of general circulation and characteristics of the active surface, the cause of their generation (Apăvăloae, et. al., 1984, 1986, 1987).