scholarly journals VERTICAL PROFILES OF WIND VELOCITY UNDER THE TYPICAL ATMOSPHERIC PRESSURE DISTRIBUTION IN THE WINTER SEASON

1999 ◽  
Vol 43 ◽  
pp. 227-232
Author(s):  
Nobuhiro MATSUNAGA ◽  
Kazuyo FUKUDA ◽  
Osamu KATAOKA
Keyword(s):  
Pressure Distribution ◽  
Wind Velocity ◽  
Atmospheric Pressure ◽  
Winter Season ◽  
Vertical Profiles ◽  
Atmospheric Pressure Distribution

scholarly journals Measurements of the amount of ozone in the Earth’s atmosphere arid its relation to other geophysical conditions.— part II

1927 ◽  
Vol 114 (768) ◽  
pp. 521-541 ◽  
Keyword(s):  
Pressure Distribution ◽  
Atmospheric Pressure ◽  
General Type ◽  
Upper Atmosphere ◽  
Earth’S Atmosphere ◽  
Atmospheric Pressure Distribution ◽  
Earth's Atmosphere

In a previous paper we have described in detail the method of measuring the total quantity of ozone in the earth’s atmosphere above any locality. Results of measurements made on about 200 days at Oxford in 1925 were also discussed, and it was shown that there was a marked connection between the amount of ozone and the general type of atmospheric pressure distribution, the amount being larger in cyclonic, and smaller in anticyclonic, conditions. As there is evidence that the ozone is entirely in the upper atmosphere, it was obviously desirable to investigate this connection further, and to see if it would throw any light on these meteorological phenomena.

scholarly journals The relation between wind velocity at 1000 metres altitude and the surface pressure distribution

1908 ◽  
Vol 80 (540) ◽  
pp. 436-443 ◽  
Keyword(s):  
Angular Velocity ◽  
Pressure Distribution ◽  
Wind Velocity ◽  
Centrifugal Force ◽  
Surface Pressure ◽  
Atmospheric Pressure ◽  
Horizontal Motion ◽  
Radius Of Curvature ◽  
Surface Pressure Distribution ◽  
The Earth

For the steady horizontal motion of air along a path whose radius of curvature is r , we may write directly the equation (ω r sin λ ± v ) 2 / r = 1/ρ ∂ p / ∂ r +(ω r sin λ ) 2 / r , expressing the fact that the part of the centrifugal force arising from the motion of the wind is balanced by the effective gradient of pressure. In the equation p is atmospheric pressure, ρ density, v velocity of moving air, λ is latitude, and ω is the angular velocity of the earth about its axis.

III—The Meteorological Limitations on Pressure Pattern Flying

1948 ◽  
Vol 1 (01) ◽  
pp. 55-61
Author(s):  
J. S. Sawyer
Keyword(s):  
Pressure Distribution ◽  
Atmospheric Pressure ◽  
Geostrophic Wind ◽  
Pressure Pattern ◽  
Low Latitudes ◽  
Atmospheric Pressure Distribution

The preceding papers indicate that the theory of pressure pattern flying assumes that the wind satisfies the conditions imposed by the geostrophic wind equation and that the atmospheric pressure distribution is not changing. These conditions are not satisfied in the atmosphere, and the errors caused by their non-fulfilment are discussed in the following paragraphs.Effect of departures of wind from geostrophic. The geostrophic wind equation is derived on the assumption that the wind blows uniformly without acceleration and without friction. These conditions are never satisfied in the atmosphere, nevertheless the practising meteorologist has found that the geostrophic wind represents a useful approximation to the true wind. There are certain exceptions of which the most important are in low latitudes and at levels below 2000 feet.

scholarly journals Computational analysis of micro wind turbine with bamboo blades for domestic applications

2021 ◽  
Vol 70 (9&10) ◽  
pp. 150
Author(s):  
J. Suraj Sayed ◽  
P. V. Sreeram ◽  
R. Ramesh Kumar
Keyword(s):  
Wind Turbine ◽  
Pressure Distribution ◽  
Wind Velocity ◽  
Structural Integrity ◽  
Average Value ◽  
Average Wind ◽  
Blade System ◽  
Blade Tip ◽  
Average Wind Velocity ◽  
Domestic Purpose

A domestic purpose micro wind turbine realised using bamboo blade is tested for the power generation at an interval of two years and compared the performance. A CFD analysis of turbine with five blade system is carried out for an average wind velocity of 2.5m/s and structural integrity of the bamboo blade unit based on the pressure distribution is assessed. For the input wind velocity, a stream lined out flow of 5.9 m/s is found when wind turbine rotates at 300 rpm and corresponding pressure distribution is found to be maximum at the expected location of blade tip as129 Pa. The static analysis shows a good margin. For 2.5 m/s, a wind turbine generates an average value of 3.8V with 0.25A (based on 15 <span>Ω</span>/10W load). The wind turbine has produced nearly the same power even after a period of two years.

scholarly journals Robust Nonparametric Methods of Statistical Analysis of Wind Velocity Components in Acoustic Sounding of the Lower Layer of the Atmosphere

Symmetry ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 961 ◽  
Author(s):  
Krasnenko ◽  
Simakhin ◽  
Shamanaeva ◽  
Cherepanov
Keyword(s):  
Statistical Analysis ◽  
Wind Velocity ◽  
Numerical Experiments ◽  
Lower Layer ◽  
Statistical Characteristics ◽  
Nonparametric Method ◽  
Vertical Profiles ◽  
Acoustic Sounding ◽  
Sodar Data ◽  
First Four Moments

Statistical analysis of the results of minisodar measurements of vertical profiles of wind velocity components in a 5–200 m layer of the atmosphere shows that this problem belongs to the class of robust nonparametric problems of mathematical statistics. In this work, a new consecutive nonparametric method of adaptive pendular truncation is suggested for outlier detection and selection in sodar data. The method is implemented in a censoring algorithm. The efficiency of the suggested algorithm is tested in numerical experiments. The algorithm has been used to calculate statistical characteristics of wind velocity components, including vertical profiles of the first four moments, the correlation coefficient, and the autocorrelation and structure functions of wind velocity components. The results obtained are compared with classical sample estimates.

Characteristics of extreme wind wave events in the Gulf of Gdańsk and associated atmospheric conditions over the Baltic Sea

2020 ◽  
Author(s):  
Aleksandra Cupial ◽  
Witold Cieslikiewicz
Keyword(s):  
Baltic Sea ◽  
Wind Velocity ◽  
Atmospheric Pressure ◽  
Wind Wave ◽  
Atmospheric Conditions ◽  
The Baltic Sea ◽  
Wave Data ◽  
Extreme Wind ◽  
Characteristic Features ◽  
The Baltic

&lt;p&gt;Nowadays, with possible changes in wind patterns and growing interests in the development of wind farms and other forms of renewable energy on the Baltic Sea, statistical characteristic of prevailing wave conditions at the site and changes in energy distribution, are essential. The Gulf of Gda&amp;#324;sk (Southern Baltic Sea) is an especially interesting area due to the presence of very characteristic long peninsula which strongly affects wave propagation and, in consequence, wave energy distribution. The objective of this work is to obtain most characteristic features of extreme storms that had significant impact on the Gulf of Gda&amp;#324;sk during the last half-century and associated meteorological conditions&lt;/p&gt;&lt;p&gt;In this study we analyse two hindcast datasets which are the result of an EU-funded project HIPOCAS (Cie&amp;#347;likiewicz &amp; Papli&amp;#324;ska-Swerpel 2008). The first one is the 44-year long reanalysis of meteorological data produced with the atmospheric model REMO (Jacob &amp; Podzun 1997).&lt;/p&gt;&lt;p&gt;The second dataset used in this study is wave data produced with wave model WAM. For the modelling of waves over the Baltic Sea, a subset of gridded REMO data were extracted. Wave data have been produced in a rectangular grid in spherical rotated coordinates with the resolution 5&amp;#8217;&amp;#215;5&amp;#8217;.&lt;/p&gt;&lt;p&gt;The principal goal of our analysis is twofold. First, we want to estimate long-term stochastic characteristics of some basic meteorological parameters and wind wave fields. Atmospheric pressure at sea level and the wind velocity at 10 m height are analysed. As far as the wind wave data are concerned, we focus on the significant wave height (&lt;em&gt;H&lt;sub&gt;s&lt;/sub&gt;&lt;/em&gt;), mean wave period and the mean direction of wave propagation. Secondly, this study aims to find out the characteristic features of atmospheric conditions causing extreme wind wave events in the Gulf of Gda&amp;#324;sk. To this end, a number of extreme storms, that are critical for a few chosen Gulf of Gda&amp;#324;sk regions, are selected based on &lt;em&gt;H&lt;sub&gt;s&lt;/sub&gt;&lt;/em&gt;&amp;#160;time series. For those selected storm periods, the storm depressions&amp;#8217; tracks and the overall evolution of atmospheric pressure and wind velocity fields are examined.&lt;/p&gt;&lt;p&gt;Our analysis showed two distinct metrological conditions that cause extreme storms in the Gulf of Gda&amp;#324;sk. Cyclones moving along the east side of the Baltic Sea are associated with strong northerly winds, which cause extremely high waves in the Gulf. On the other hand, cyclones travelling east in the zonal direction over the northern Baltic bring strong westerly winds. They significantly raise &lt;em&gt;H&lt;sub&gt;s&lt;/sub&gt;&lt;/em&gt;, although not to the extent observed for the northerly winds.&lt;/p&gt;&lt;p&gt;In our study, we also look for the essential characteristics of the extreme meteorological conditions via results of the Empirical Orthogonal Functions (EOF) method, applied to the wind velocity vector fields.&lt;/p&gt;&lt;p&gt;Computations performed within this study were conducted in the TASK Computer Centre, Gda&amp;#324;sk with partial funding from eCUDO.pl project and the Project for Young Scientist No. 539-G210-B412-19.&lt;/p&gt;&lt;p&gt;Cie&amp;#347;likiewicz, W. &amp; Papli&amp;#324;ska-Swerpel, B. (2008), Coastal Engineering, &lt;strong&gt;55&lt;/strong&gt;, 894&amp;#8211;905.&lt;/p&gt;&lt;p&gt;Jacob, D. &amp; Podzun, R., (1997). Meteorol. Atmos. Phys., &lt;strong&gt;63&lt;/strong&gt;, 119&amp;#8211;129.&lt;/p&gt;

DIURNAL BEHAVIOR AND BITING HABITS OF BLACK FLIES (DIPTERA: SIMULIIDAE) IN THE FORESTS OF QUEBEC

1960 ◽  
Vol 38 (3) ◽  
pp. 489-497 ◽  
Author(s):  
L. S. Wolfe ◽  
D. G. Peterson
Keyword(s):  
Relative Humidity ◽  
Light Intensity ◽  
Wind Velocity ◽  
Atmospheric Pressure ◽  
Flight Activity ◽  
Black Flies ◽  
Late Afternoon ◽  
Early Afternoon ◽  
Diurnal Behavior

Studies in the region of Baie Comeau, Quebec, from 1954 to 1956, showed that black flies were most active in the morning 1 to 2 hours after dawn and in the evening [Formula: see text] to 1 hour before sunset. Flight activity appeared to depend on light intensity if the temperature was not below 45° F, the wind velocity not above 2 m.p.h., and the relative humidity not below 50%. In the morning, activity was greatest at higher levels of light intensity, i.e., 20 ft-c, than in the evening, 5 ft-c. Activity increased before thunderstorms and rain and the increase appeared related more to the change in light intensity than to changes in atmospheric pressure or humidity. At night, black flies moved to resting places in the tops of the trees, probably because of the more suitable light intensity at the higher levels just before dark. Oviposition commenced in the late afternoon and continued until dark except on overcast days, when it commenced in early afternoon. Simulium (Simulium) venustum Say bit man mainly on the back of the neck.

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