Search Results

You are looking at 1 - 5 of 5 items for

  • Author: Sfîcă Lucian x
Clear All Modify Search
Open access

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

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).

Open access

Ion Constantin, Baltag Emanuel Ştefan, Ursu Adrian, Sfîcă Lucian, Ignat Alina Elena and Stoleriu Cristian Constantin

Abstract

The avian habitats in Eastern Europe are poorly managed in last decades. It is of highly noteworthy influence importance to obtain more information regarding the link between birds’ presence and environmental features in wetlands to improve this poorly managed system. In our study we investigated the effects of the various habitat, landscape fragmentation and weather variables on the bird assemblages in Eastern Romania, described by diversity, species richness and abundance of non-passerine birds in wetlands. Poisson regression modelling revealed wetland area, wetland heterogeneity, proportion of open-water, density of patches and habitats, landscape shape and temperature conditions have a noteworthy influence on the bird assemblages (p<0,05). Our results suggest that the link between environmental features and birds’ assemblage, in our study areas could be dependent on the presence of the emergent vegetation (shelter / reproduction zones), the balance between open-water area (feeding / nesting zones) and also other variables, as the temperature, the presence of the human living facilities and/or intensive fish nurseries in the neighboring zones. Waterbird distribution and abundance in eastern part of Romania are driven by similar factors to other part of the world and this study could be one of the first published on the topic in a region where It is a lack of information on waterbirds ecology. Such studies would bring valuable information about the ecologic factors influencing the lives of the birds, in the areas that were not stueid before, resulting in better conservation efforts and wetland protection, in estern part of Europe.

Open access

Lucian Sfîcă, Iulian Iordache, Pavel Ichim, Alina Leahu, Marius-Mihai Cazacu, Silviu Gurlui and Cătălin-Răzvan Trif

Abstract

The aim of this study is to evaluate the role of the weather conditions and local climate on the temporal and spatial variability of particulate matters (PM 10) in Iași city which is facing major pollution problems in the recent years. Daily data from 4 monitoring stations of Environmental Protection Agency-Iași–for main weather parameters and particulate matters – and the temperature from an inner temperature and relative humidity observation network inside the city were used for a three year study (2013-2015). Linear correlation, composite analysis and multiple regression are the main statistical methods applied in the analysis. In brief, the most important meteorological parameters enhancing air pollution in Iași seem to be represented by thermal inversions developing in the region strongly related to local climate conditions. The Pearson correlation coefficient (stronger than -0.40) between PM10 and thermal gradient, the difference in the PM10 concentration exceeding 20 μg/m3 between strong thermal inversions and unstable conditions and the leading role of thermal gradients in multiple regression are the main indicators of the great role of thermal inversion in generating and sustaining pollution conditions in this area. The maximum concentrations of PM10 occur in May and March, gathering more than 30% of the days for the entire year. Complementary studies were taken into account in order to analyse the aerosol optical properties retrieved from Aerosol Robotic Network (AERONET-NASA).

Open access

Irimia Liviu Mihai, Patriche Cristian Valeriu, LeRoux Renan, Quénol Herve, Tissot Cyril and Sfîcă Lucian

Abstract

Climate projections have revealed the perspective of changing the climate of the world's wine regions in the coming decades by diversifying heliothermal resources. Research in the Cotnari winegrowing region over the past decade has shown that the local climate has been affected by such developments especially after 1980. This research continues the series of studies on the climate of the Cotnari winegrowing region through projections of the climatic conditions for the 2020-2100 time period based on the RCP 4.5 scenario. Average annual temperature, warmest month temperature, precipitation during the growing season, length of the growing season and the Huglin, IAOe and AvGST bioclimatic indices for the 2020-2050, 2051-2080 and 2081-2100 time periods indicate the evolution of Cotnari area climate towards suitability for red wines and loss of suitability for the white wines. Climatic suitability classes for wine production, shift between 2020-2100 to the higher, cooler zone of the winegrowing region, narrowing down their surface and disappearing successively at the maximum altitude of 315 m asl. They are further replaced from the lower zone by classes specific to warmer climates. The suitability for white wines, specific to wine region, disappears at the maximum altitude of 315 m asl around 2060, being replaced by climate suitability for the red wine production. The average temperature of the growing season will exceed 19.5°C after 2080, becoming unsuitable for the production of red quality wines of Cabernet Sauvingnon variety. After 2050, in the lower zone of the winegrowing region the warm IH5 class, suitable for Mediterranean varieties such as Carignan and Grenache will install, as compared to temperate IH3 class which characterizes today the lower zone and allows the production of white wines of the local Feteasca albă, Grasa de Cotnari, Frâncușa and Tămâioasa românească varieties. The results suggest the need to develop strategies for adapting the viticulture of the Cotnari area to climate change.