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Waves represent the most important factor in the evolution of the coastal zones. One of the main causes leading to the wave formation is the movement of the air masses. A particular influence on the wave agitation regime in the littoral sector is exerted by the shore configuration, water depth, bottom relief and the formation of ice cover in winter. The scope of this paper is to analyze the historical data on the wind and waves in the Danube discharge area. The emphasis is on the maximum values of wave heights and the insurance curves resulting from calculations, in the maritime sector of the Danube Delta. The research incorporates data from Jibrieni, Snake Island and Sulina stations, covering a timeframe of 5 years. Observation data have been processed and presented in order to generate an overall picture of these phenomena that affect the spatial unfolding of the shore. Furthermore, of a particular importance in the calculations is determining the correlations between wind speeds and wave height. The results suggest that the characteristics of the waves acquire significant values. This knowledge can be utilized in designing marine vessels or hydrotechnical structures. During the extreme events, storm-induced waves and the sea level are key factors in the evolution of the shore. The coastline response to these conditions takes into account the characteristics of the storm (intensity, direction and duration). In this respect, the hypothesis of the waves in the development stage was used, analyzing for each different wind direction the wind speed in correlation with wave height values. In conclusion, the present paper offers an overview of the wave characteristics in the maritime sector under different wind conditions. [ABSTRACT FROM AUTHOR]

The mobile environmental laboratory was located in a fuel distribution station located on a heavy traffic national road in Petroșani City, Hunedoara County (Romania) to investigate dust and gas pollution, as well as dispersion of pollutants to nearby homes, using the AUSTAL VIEW software. Measurements were performed over a period of eight hours in two working days in order to better capture the movement of air masses and the dispersion of measured pollutants. In the event of accidental spills of chemicals or chemical vapors into the environment that may come from gas stations, the ALOHA (Areal Locations of Hazardous Atmospheres) computer program was used, a free program developed and used by the USEPA (Environmental Protection Agency United States). The paper, structured on two levels, aims to quickly identify pollutants in the area of interest by simultaneously determining several samples and analysing the dispersion of concentrations, as well as assessing consequences of accidental pollution with flammable/volatile substances from a fuel station, to estimate the spatial extent of such an unwanted event. The simulation of volatile chemicals dispersion was performed for the accidental leakage of fuel into the environment when transferring fuel from tanker to reservoirs. Accidental release of toxic/flammable/explosive substances may have serious consequences for workers or neighbouring population, therefore the need to establish safety zones based on best practices in the field and on a scientific basis is fully justified. [ABSTRACT FROM AUTHOR]

Cut-off low altitude cyclones (COLs) are characterized by the presence of small cold air masses detached from the polar vortex as a consequence of Rossby waves development. Their displacement at a lower latitude is capable to induce higher atmospheric instability and they have a great influence on the amount of precipitation over Romania between April and September. This paper is based on the analysis from a synoptic point of view of the days when the precipitation amount was greater than 10 mm between 1961 and 2010, during the warm semester (April - September). Sea level pressure maps from Deutsche Wetterdienst and 500 hPa geopotential height from Climate Forecast Systems of NOAA, available at www.wetter3.de, the GFS forecasting numerical model (Global Forecast System) were used for the synoptic analysis. This study, by analyzing all days with the amount of rainfall greater than 10 mm, and by making all the cartographic materials presented, aims to highlight the most affected areas by them, using ROCADA dataset. Out of the total of 5,340 days with the precipitation amount greater than 10 mm at the level of Romania, 1498 of them (28%) are associated with COLs activity. In April, 74 days (4.94%) with COLs activity were found. Starting May, the COLs activity is much better evidenced, being present in 220 days (14.69%), in June 408 days (27.24%) and 437 days in July (29.17%). In August, with 252 days (16.82%) and in September with 107 days (7.14%), the COLs activity started to decrease. [ABSTRACT FROM AUTHOR]

Climate change and its impact on the environment is an urgent problem of the present time, causing hydrological changes and ecosystem change. As a result, formed ecosystem representing less valuable in economic terms, low productivity. Therefore, study of climate change is an important and urgent task. Global climate changes in the South part of Russia is reflected in the warming of the winter period and an increase in the amount of precipitation during the cold season. This paper analyzes the changes in meteorological conditions in Rostov region and its influence on water regime of the Lower Don. Rostov region is located in the Western subdomain of the Atlantic-continental steppe region, temperate zone. The climate of the region is moderate continental, formed under the influence of air mass transfer from the Atlantic, meridional Northern and southern transfers and transformation of air masses. Flat terrain favors the flow of air masses of different origin. The river flow is formed in the steppe zone. Spring flood depends on soil moisture and moisture reserve in the catchment area. The total water content of the river depends on the amount of winter precipitation and air temperature. The main flow (60 - 65%) formed by meltwater in the spring, 25-30% - through underground supply and 3-5% at the expense of atmospheric precipitation. River is characterized by high and long spring flood. In natural conditions, it accounts for about 70% of annual runoff. Tsimlyanskoe reservoir smoothed seasonal distribution of runoff. Until 1952, spring floods accounted for 78% of runoff and 22% for the rest of the year. After the launch of the reservoir, the situation changed. Only 47% the flow of the river falls in the spring. The rivers of the Don basin are now experiencing a decrease in spring runoff. At the same time, there is an increase in summer, autumn and winter runoff in comparison with the period of climatic norm. Analysis of the annual distribution of runoff led to the allocation of two periods: before the construction of the Tsimlyansk reservoir and after the start of operation. Since 2007, there has been a constant decrease in the water content of the river, which lasted until 2016, the low-water regime. [ABSTRACT FROM AUTHOR]

The paper deals with height determination in indoor environment using inertial sensors (accelerometers, gyroscopes) and barometer built in a smartphone, which is very important to detect upstairs and downstairs motion of the users. The algorithm proposed uses the barometric formula for height determination and the relationship between the decreasing barometric pressure and increasing height. The main advantage of the use of barometer is the long-term accuracy, because the algorithm is not recursive. The problem of the barometric measurement lies in the local disturbances of barometric pressure which is caused by temperature changes (increasing temperature cause increase of the pressure) and instable air mass (air-conditioning cause inhomogeneous air mass). These local disturbances of the barometric pressure lead to increase of errors in height determination. Reduce the errors caused by the temperature change, accelerometer data using step detection with average step height (without integration process), are used. Double integration of the acceleration measured is used only in specific situations (only in case when elevator is used during the movement). The benefit of the use of combined processing of barometer and accelerometer data against the use of only barometer or accelerometer data is analyzed on the base of experimental measurements. [ABSTRACT FROM AUTHOR]