共查询到20条相似文献，搜索用时 78 毫秒
1.
S. N. Kulichkov N. D. Tsybulskaya I. P. Chunchuzov V. A. Gordin Ph. L. Bykov A. I. Chulichkov V. G. Perepelkin G. A. Bush E. V. Golikova 《Izvestiya Atmospheric and Oceanic Physics》2017,53(4):402-412
Internal gravity wave (IGW) data obtained during the passage of atmospheric fronts over the Moscow region in June–July 2015 is analyzed. IGWs were recorded using a group of four microbarographs (developed at the Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences) located at distances of 7 to 54 km between them. Regularities of variations in IGW parameters (spatial coherence, characteristic scales, propagation direction, horizontal propagation velocity, and amplitudes) before, during, and after the passage of an atmospheric front over the observation network, when the observation network finds itself inside the cyclone and outside the front, are studied. The results may be useful in studying the relationships between IGW effects in different physical fields at different atmospheric heights. It is shown that, within periods exceeding 30 min, IGWs are coherent between observation points horizontally spaced at distances of about 60 km (coherence coefficient is 0.6–0.9). It is also shown that there is coherence between wave fluctuations in atmospheric pressure and fluctuations in horizontal wind velocity within the height range 60–200 m. A joint analysis of both atmospheric pressure and horizontal wind fluctuations has revealed the presence of characteristic dominant periods, within which cross coherences between fluctuations in atmospheric pressure and wind velocity have local maxima. These periods are within approximate ranges of 20–29, 37–47, 62–72, and 100–110 min. The corresponding (to these dominant periods) phase propagation velocities of IGWs lie within an interval of 15–25 m/s, and the horizontal wavelengths vary from 52 to 99 km within periods of 35 to 110 min, respectively. 相似文献
2.
The first experimental studies of the spatial oblique and vertical spectra of temperature fluctuations in a stably stratified troposphere at heights of 2 to 8 km were conducted. The measurements were taken over northern European Russia. The spectra cover the wave number range from 5 10?4 to 3 10?2 rad/m. The estimates obtained for the spectral density are analyzed on the basis of a model developed previously for the three-dimensional (3D) spectrum of temperature fluctuations generated by a statistical ensemble of internal waves. This model made it possible to consider both oblique and horizontal spectra from a unified point of view and to use a unified set of parameters on the basis of the 3D spectrum concept. The quantitative estimates obtained for the parameters of the 3D spectrum have shown that large-scale temperature inhomogeneities with a vertical size of more than a hundred meters are strongly extended along the land surface. They have approximately the same form; their horizontal sizes are at least 20 times greater than their vertical sizes. The anisotropy of temperature inhomogeneities decreases with a decrease in their vertical sizes and reaches 1.5–2 for vertical sizes of 10–20 m or smaller. 相似文献
3.
Izvestiya, Atmospheric and Oceanic Physics - An updated numerical model of the propagation of a set of spectral harmonics of internal gravity waves (IGWs) in the inhomogeneous atmosphere from the... 相似文献
4.
渤海湾风浪场的数值模拟 总被引：14，自引：1，他引：13
采用SWAN模型对渤海湾在定常风和非定常风作用下的波浪场进行了模拟,并利用黄骅港附近波浪统计资料对模拟结果进行了验证。结果表明：SWAN模型较好地模拟了渤海湾在定常风和非定常风作用下风浪成长和传播过程。此外,还应用ADCIRC潮流模型,初步探讨了潮流对波浪要素的影响：(1)无流存在时,波高的成长和波周期的变化是一条光滑的曲线,但当有流加入时,由于其流速和水位在一个潮周期内随时间的变化足不均匀的,其对波浪成长产生影响,使波高和周期呈不规则变化;(2)波浪成长初期,流对波高增长的影响并不明显,但当波高增大到一定程度时,流的存在对波高的影响是很明显的。 相似文献
5.
次重力波（Infragravity Wave，IGW）是一种频率较低（0.05~0.005 Hz），波长较长（约10 km）的表面重力波。由IGW引起的海表面高度变化会被宽刈幅干涉高度计SWOT （Surface Water and Ocean Topography，SWOT）卫星观测到，因此在使用SWOT观测的海表面高度来反演中尺度、次中尺度大洋环流时，IGW是一种重要的误差来源。根据数值模型模拟的全球IGW时空分布特征，本文以IGW最为活跃的东北太平洋和欧洲西北陆架附近大西洋为研究海域，估算了上述海域由IGW所引起的海表面高度变化，并将计算结果与SWOT Simulator模拟的轨道噪声（±5 cm）比较，首次定量地估算了IGW在SWOT观测海表面高度时的干扰程度。研究表明，IGW所引起的厘米量级的海表面高度变化在SWOT卫星观测海表面流场时是一种重要的，不可忽略的误差来源。在大西洋欧洲西北陆架海域，冬季IGW对海表面高度的贡献可达到SWOT卫星噪声要求水平的25%；然而，对于大陆架狭窄的美国西岸太平洋而言，由岸线产生的IGW将迅速传入深海海域，在广阔的范围内产生显著的"噪声"影响，在SWOT反演海表面流场时由IGW引起的误差将达到SWOT卫星噪声要求水平的15%。 相似文献
6.
This paper presents the results of processing sea-surface optical images in the coastal zone of the Sea of Japan with manifestations of internal gravity waves (IGWs) in the region of the Gamov Peninsula and the results of an analysis of IGW field observations in the same region. The following parameters of IGWs have been determined from the results of processing: their lengths and phase velocities. We calculate the IGW parameters in the region of observations using a mathematical model that takes into account the field data on the vertical stratification of coastal waters and the nonlinearity of the wave process. A comparison of the IGW parameters obtained from model calculations with the parameters obtained from the processing of optical images demonstrates a good agreement between them. 相似文献
7.
Kan V. Gorbunov M. E. Shmakov A. V. Sofieva V. F. 《Izvestiya Atmospheric and Oceanic Physics》2020,56(5):435-447
Izvestiya, Atmospheric and Oceanic Physics - In this paper, we discuss a method for reconstructing the parameters of internal gravitational waves (IGWs) in the stratosphere from amplitude... 相似文献
8.
Shved G. M. Novikov S. S. Gavrilov N. M. 《Izvestiya Atmospheric and Oceanic Physics》2020,56(1):43-51
Izvestiya, Atmospheric and Oceanic Physics - A spatial distribution model for air density perturbations during the propagation of internal gravity waves (IGWs) is used to derive estimates for... 相似文献
9.
Kan V. Gorbunov M. E. Fedorova O. V. Sofieva V. F. 《Izvestiya Atmospheric and Oceanic Physics》2020,56(6):564-575
Izvestiya, Atmospheric and Oceanic Physics - The method of reconstructing the global distribution of statistical parameters of internal gravity waves (IGWs) in the atmosphere has been tested using... 相似文献
10.
11.
Hirofumi Hinata Satoshi Fujii Keita Furukawa Tomoya Kataoka Masafumi Miyata Takashi Kobayashi Masahiro Mizutani Takahiro Kokai Nobuyoshi Kanatsu 《Estuarine, Coastal and Shelf Science》2011
Signals from the tsunami waves induced by the March 11, 2011 moment magnitude (Mw) 9.0 Tohoku-Oki earthquake and from subsequent resonances were detected as radial velocity variability by a high-frequency ocean surface radar (HF radar) installed on the eastern coast of the Kii Channel, at a range of about 1000 km from the epicenter along the eastern to southern coasts of Honshu Island. A time–distance diagram of band-passed (9–200 min) radial velocity along the beam reveals that the tsunami waves propagated from the continental shelf slope to the inner channel as progressive waves for the first three waves, and then natural oscillations were excited by the waves; and that the direction of the tsunami wave propagation and the axis of the natural oscillations differed from that of the radar beam. In addition, spectral analyses of the radial velocities and sea surface heights obtained in the channel and on the continental shelf slope suggest complex natural oscillation modes excited by the tsunami waves. 相似文献
12.
N. M. Gavrilov A. V. Koval’ A. I. Pogorel’tsev E. N. Savenkova 《Izvestiya Atmospheric and Oceanic Physics》2013,49(4):367-374
We have developed a parameterization of the dynamical and thermal effects of stationary orographic waves (SOWs) generated by the earth’s surface topography and included it into the general circulation model of the middle and upper atmosphere. We have analyzed the sensitivity of atmospheric general circulation at tropospheric to thermospheric altitudes to the impact of SOWs propagating from the troposphere. Changes in atmospheric circulation due to variations in the SOW generation and propagation have been considered for different seasons. It has been shown that, during solstices, the main dynamical and thermal impacts the middle atmosphere of winter hemispheres, where the SOW-induced changes in the velocity of zonal circulation can reach 30%. During equinoxes, the SOW impact is distributed more homogeneously between the Northern and Southern hemispheres, and the relative changes in the velocity of zonal circulation of the middle atmosphere may constitute 10%. 相似文献
13.
Traditional wave steepness s=H/L does not define steep asymmetric waves in a random sea uniquey. Three additional parameters characterising single zero-downcross waves in a time series are crest front steepness, vertical asymmetry factor and horizontal asymmetry factor. Results for steepness and asymmetry from zero-downcross analysis of wave data obtained from full scale measurements in deep water on the Norwegian continental shelf in 58 time series are presented. The analysis demonstrates clearly the asymmetry of both “extreme waves” and the highest waves. The period and height of the highest waves are also given together with their correlation to spectral parameters. The measured maximum wave heights are also compared with predicted values of maximum wave heights showing good agreement. 相似文献
14.
Internal tide and nonlinear internal wave behavior at the continental slope in the northern south China Sea 总被引：16，自引：0，他引：16
《Oceanic Engineering, IEEE Journal of》2004,29(4):1105-1130
A field program to measure acoustic propagation characteristics and physical oceanography was undertaken in April and May 2001 in the northern South China Sea. Fluctuating ocean properties were measured with 21 moorings in water of 350- to 71-m depth near the continental slope. The sea floor at the site is gradually sloped at depths less than 90 m, but the deeper area is steppy, having gradual slopes over large areas that are near critical for diurnal internal waves and steep steps between those areas that account for much of the depth change. Large-amplitude nonlinear internal gravity waves incident on the site from the east were observed to change amplitude, horizontal length scale, and energy when shoaling. Beginning as relatively narrow solitary waves of depression, these waves continued onto the shelf much broadened in horizontal scale, where they were trailed by numerous waves of elevation (alternatively described as oscillations) that first appeared in the continental slope region. Internal gravity waves of both diurnal and semidiurnal tidal frequencies (internal tides) were also observed to propagate into shallow water from deeper water, with the diurnal waves dominating. The internal tides were at times sufficiently nonlinear to break down into bores and groups of high-frequency nonlinear internal waves. 相似文献
15.
We perform the numerical analysis of the process of propagation of long waves in the northwest part of the Black Sea and consider
ten possible zones of the seismic generation of tsunamis. The numerical analysis is performed on a grid with steps of 500 m.
It is shown that the location of the tsunami source significantly affects the distribution of the heights of waves along the
coast. As a rule, the most intense waves are formed in the closest part of the coast. The earthquakes in the South-Coast seismic
zone do not lead to the formation of tsunamis in the west part of the sea. Only strong earthquakes in the northwest part of
the sea can be responsible for noticeable oscillations of the Black-Sea level. The period of tsunamis near Odessa is close
to 1 h and depends on the magnitude of the earthquake. In the region of Sevastopol, this period is 2--3 times smaller. In
the major part of the coastal points, the extreme elevations and lowerings of the sea level do not exceed (in modulus) the
initial displacements of the sea surface at the source of tsunamis. An intensification of waves emitted from the zones of
generation located in the deeper part of the investigated region was observed for some parts of the Romanian coast and the
west coast of Crimea. As the magnitude of the earthquake increases, the intensification of waves near the coast becomes more
pronounced. 相似文献
16.
We develop techniques of numerical wave generation in the time-dependent extended mild-slope equations of Suh et al. [1997. Time-dependent equations for wave propagation on rapidly varying topography. Coastal Engineering 32, 91–117] and Lee et al. [2003. Extended mild-slope equation for random waves. Coastal Engineering 48, 277–287] for random waves using a source function method. Numerical results for both regular and irregular waves in one and two horizontal dimensions show that the wave heights and the frequency spectra are properly reproduced. The waves that pass through the wave generation region do not cause any numerical disturbances, showing usefulness of the source function method in avoiding re-reflection problems at the offshore boundary. 相似文献
17.
S. F. Dotsenko 《Physical Oceanography》1998,9(5):323-331
The paper analyses the effect of non-linearity and bottom friction on propagation of tsunami-type surface waves from the abyssal
part of the Black Sea towards the shelf zone. The study relies, on numerical solution of unidimensional non-linear equations
for long waves, using the finite-difference technique. Numerical experiments have been conducted for the bottom profile continental
slope and shelf, with the full wave reflection being prescribed at a 10-m depth contour. It has been shown that the major
role in transforming solitary waves belongs to non-linear topographic factors rather than to dissipation. The reflected wave
has been found to be non-linearly distorted, and wave heights in the Black Sea coastal zone have been found to increase by
many times.
Translated by Vladimir A. Puchkin. 相似文献
18.
Large-scale interceptors constitute the main structure of offshore self-driven floating marine litter collection devices,and the structural stability of such interceptors under the action of waves directly influences the overall safety of the device.When the ratio of the diameter of a horizontal cylinder in such interceptors to the incident wavelength is larger than 0.25,the wave force can be calculated by using the diffraction theory,by considering the problem as that of the interaction between the waves and a partially immersed large-scale horizontal cylinder.In this study,an analytical approach to calculate the wave force on a partially immersed large-scale horizontal cylinder was formulated by using the stepwise approximation method.Physical model tests were conducted to investigate the effects of different factors(wave height,period,and immersion depth)on the wave force on a large-scale horizontal cylinder under conditions involving short-period waves.The results show that both horizontal and vertical wave forces on the cylinder increase as the wave height(immersion depth)increases in most cases.The vertical wave force decreases with the decrease of the period.For the horizontal wave force,it increases with the decrease of the period when the wavelength is larger than the diameter of the cylinder and decreases with the decrease of the period when the wavelength is smaller than the diameter of the cylinder. 相似文献
19.
Evidence has been found for the teleconnection of Indian Ocean Dipole mode (IOD) events in the southern high latitude sea
surface pressure field, although the mechanisms that might lead to such far-reaching links remain unresolved. Based on the
teleconnection pattern between IOD and the climate anomaly in the upper troposphere, we propose one such mechanism here: the
energy propagation theory of the atmospheric planetary wave. Ray traces of the atmospheric planetary waves suggest that the
energy propagation of the waves could be responsible for the teleconnection between IOD and tropospheric climate anomalies
in southern high latitudes. 相似文献
20.
Philip L.-F.LIU 《中国海洋工程》1998,(2)
The nonlinear capillary-gravity wave produced by a vertically oscillating plate,in which thecontact-angle model is considered,is studied by use of the Boundary Integral Equation Method(BIEM).The present numerical experiment shows that the code is robust and efficient for modeling the generationand propagation of capillary-gravity waves.It is found that the wave heights of stationary periodicnonlinear waves radiated away from the plate are dependent on the parameters involved in the contact-an-gle model.The effect of the contact-angle hysteresis and the nonlinearity of capillary-gravity waves on thewave profile is discussed in the paper. 相似文献