Search results for "wind direction"
showing 10 items of 18 documents
The influence of the wind direction and plants on the variability of topsoil magnetic susceptibility in industrial and urban areas of southern Poland
2016
Volume magnetic susceptibility (κ) was measured on the soil surface and in the vertical topsoil profile within a 300 km2 area located in an urban-industrial conurbation. The results were compared to plant species compositions in the forest storeys, elevation above sea level, and terrain geomorphology. The content and mineral composition of the magnetic fraction were determined in the soil horizons. It was found that the extent of the area with enhanced topsoil magnetic susceptibility was similar to the dominant wind direction (south–west). Enhanced κ values were observed for the soil at the forest margin on the leeward side of the emitters as well as at sites located on exposed local elevat…
Fluorescent biological aerosol particle measurements at a tropical high-altitude site in southern India during the southwest monsoon season
2016
An ultraviolet aerodynamic particle sizer (UV-APS) was continuously operated for the first time during two seasons to sample the contrasting winds during monsoon and winter to characterize the properties of fluorescent biological aerosol particles (FBAPs), at a high-altitude site in India. Averaged over the entire monsoon campaign (1 June–21 August 2014), the arithmetic mean number and mass concentrations of coarse-mode (> 1 µm) FBAPs were 0.02 cm−3 and 0.24 µg m−3, respectively, which corresponded to ∼ 2 and 6 % of total aerosol loading, respectively. Average FBAP number size distribution exhibited a peak at ∼ 3 µm, which is attributed to the fungal spores, as supported by scanning …
Banner clouds observed at Mount Zugspitze
2012
Abstract. Systematic observations of banner clouds at Mount Zugspitze in the Bavarian Alps are presented and discussed. One set of observations draws on daily time lapse movies, which were taken over several years at this mountain. Identifying banner clouds with the help of these movies and using simultaneous observations of standard variables at the summit of the mountain provides climatological information regarding the banner clouds. In addition, a week-long measurement campaign with an entire suite of instruments was carried through yielding a comprehensive set of data for two specific banner cloud events. The duration of banner cloud events has a long-tailed distribution with a mean of…
Spatio-temporal variability of fog-water collection in the eastern Iberian Peninsula: 2003-2012
2019
Abstract Among the different inputs involved in the hydrological system, fog water measured by man-made passive devices is one of the most unknown components, although it could be an additional water resource for specific environmental applications (forest restoration, forest firefighting, etc.). Focusing on the Mediterranean Iberian Peninsula, the aim of this work is to quantify fog-water collected by a 24-fog-stations network spread across three latitudinal sectors with different locations (coastal, pre-littoral and inland), and to determine the most productive sites. Measurements from the network show that distance-to-sea, latitude or elevation differences between stations are factors af…
PCA analysis of wind direction climate in the baltic states
2021
Wind direction is one of the fundamental parameters of weather. In this study we investigate the wind direction climate 10 m above surface level in the Baltic States (Estonia, Latvia, Lithuania). The analysis of wind direction over larger regions is usually hindered by the fact that wind direction is a circular variable, which means that averaged values are meaningless. Here we show how Principal Component Analysis (PCA) can be applied to give a large scale overview of typical wind direction patterns in the region. Here we apply PCA to both observational and reanalysis data. The most significant wind direction patterns are detected in both synoptic scale and mesoscale, and we attempt to lin…
Dust mobilization due to density currents in the Atlas region: Observations from the Saharan Mineral Dust Experiment 2006 field campaign
2007
[1] Evaporation of precipitation is a ubiquitous feature of dry and hot desert environments. The resulting cooling often generates density currents with strong turbulent winds along their leading edges, which can mobilize large amounts of dust. Mountains support this process by triggering convection, by downslope acceleration of the cool air, and by fostering the accumulation of fine-grained sediments along their foothills through the action of water. For the Sahara, the world's largest dust source, this mechanism has been little studied because of the lack of sufficiently high resolution observational data. The present study demonstrates the frequent occurrence of density currents along th…
Impact of Building Layouts on Wind Turbine Power Output in the Built Environment: A Case Study of Tsu City
2014
In city planning, it is important to consider the future growth of renewable energy systems in the built environment. Wind speed analysis in the built environment is very important for analysing the wind turbine performance installed in the built environment. In this work, building topologies / layouts in Tsu city are considered for investing the wind speed distributions and directions. Wind speed profile in the built environment are developed by using CFD-ACE+. This work focusses on the analysis of the wind speed directions and distribution characteristics for finding out the proper location of the wind turbines in the built environment. The wind speed profiles and their directions and win…
Analysis of four years of ceilometer-derived aerosol backscatter profiles in a coastal site of the western Mediterranean
2018
Abstract We present the analysis of four years of measurements by a CL51 ceilometer in Burjassot (39.51 N, 0.42 W), a research station in the western Mediterranean coast. The 1-min resolution profiles of the CL51 are corrected, calibrated, grouped and cloud-screened to create a 1-h resolution database of aerosol backscatter profiles at 910 nm (βa) spanning from July 2013 to August 2017. A total of 21,247 βa profiles are obtained, covering 58% of the considered period. The analysis of the βa profiles as a function of the main aerosol in the atmosphere reveals that dust arrives at Burjassot mainly in the form of elevated layers, with a highest impact between 1 and 4 km. The βa profiles obtain…
Hourly Forecasting of SO2 Pollutant Concentration Using an Elman Neural Network
2006
In this paper the first results produced by an Elman neural network for hourly SO2 ground concentration forecasting are presented. Time series has been recorded between 1998 and 2001 and are referred to a monitoring station of SO2 in the industrial site of Priolo, Syracuse, Italy. Data has been kindly provided by CIPA (Consorzio Industriale per la Protezione dell'Ambiente, Siracusa, Italia). Time series parameters are the horizontal and vertical wind velocity, the wind direction, the stability classes of Thomas, the base level of the layer of the atmospheric stability, the gradient of the potential temperature and the difference of the potential temperature of reference.
Dispersion models and air quality data for population exposure assessment to air pollution
2014
Evaluating the extent of exposure to chemicals in absence of continuous measurements of their concentration in air and direct measures of personal exposure is crucial for epidemiological studies. Dispersion models can be a useful tool for reproducing spatio-temporal distribution of contaminants emitted by a specific source. However, they cannot easily be applied to short-term epidemiological studies because they require precise information on daily emission scenarios for a long time, which are generally not available. The aim of this study was to better assess the exposure in the industrial area of Brindisi, which suffers from various critical epidemiological situations, by integrating air …