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1.
2.
We propose a dynamical model for the prediction of random components of natural processes. The model is based on the system concept of adaptive balance of causes (ABC-model) and contains dynamic equations for the coefficients of influence adapted to the correlations existing in the predicted processes. To improve the accuracy of predictions, we consider two possible schemes of assimilation of the data of observations in the equations of the ABC-model, namely, the Kolmogorov and Kalman schemes. Both schemes are oriented toward the application of sample correlation coefficients for the prediction of time series of measurements and, hence, take into account the nonstationarity of actual natural processes. We present some examples of prediction of the simulated time series clarifying the algorithms of assimilation of the data of observations. A conclusion is made that the methods of systems modeling and adaptive prediction of random processes by the ABC-method are quite promising.  相似文献   

3.
Local balance in the air-sea boundary processes   总被引:1,自引:0,他引:1  
In the course of the new treatment of the growth process of wind waves presented in part I of the present series of the articles, there was a point where the wave energy and wave momentum were not related correctly. This point has been revised with critical argument, and at the same time, the form of the ratior, between the wind stress that directly enter the wind waves and the total wind stress, has been derived analytically. The growth equation, under the condition that the wind stress is constant, is still the same with that derived in part I, with the exception that the ratior is given analytically.A comparison between the ratior obtained analytically and that estimated empirically in part I, raises a problem to be studied about the wave current of the actual wind waves.  相似文献   

4.
Local balance in the air-sea boundary processes   总被引:2,自引:0,他引:2  
A combination of the three-second power law, presented in part I for wind waves of simple spectrum, and the similarity of the spectral form of wind waves, leads to a new concept on the energy spectrum of wind waves. It is well substantiated by data from a wind-wave tunnel experiment.In the gravity wave range, the gross form of the high frequency side of the spectrum is proportional tog u * –4, whereg represents the acceleration of gravity,u * the friction velocity, the angular frequency, and the factor of proportionality is 2.0×l0–2. The wind waves grow in such a way that the spectrum slides up, keeping its similar form, along the line of the gross form, on the logarithmic diagram of the spectral density,, versus. Also, the terminal value of, at the peak frequency of the fully developed sea, is along a line of the gradient ofg 2 –5.The fine structure of the spectrum from the wind-wave tunnel experiment shows a characteristic form oscillating around the –4-line. The excess of the energy density concentrates around the peak frequency and the second- and the third-order harmonics, and the deficit occurs in the middle of these frequencies. This form of the fine structure is always similar in the gravity wave range, in purely controlled conditions such as in a wind-wave tunnel. Moving averages of these spectra tend very close to the form proportional to –5.As the wave number becomes large, the effect of surface tension is incorporated, and the –4-line in the gravity wave range gradually continues to a –8/3-line in the capillary wave range, in accordance with the wind-wave tunnel data. Likewise, the –5-line gradually continues to a –7/3-line.Also, through a discussion on these results, is suggested the existence of a kind of general similarity in the structure of wind wave field.  相似文献   

5.
A new growth equation for wind waves of simple spectrum is presented upon three basic concepts. The period and the wave height of significant waves in dimensionless forms, which are considered to correspond to the peak frequency and the energy level, respectively, are used as representative quantities of wind waves. One of the three basic concepts is the concept of local balance, and the other two concern the acquisition of wave energy and the dissipation of wave energy, respectively. It is shown from some actual data that the equation, together with two universal constants concerning the acquisition and the dissipation of wave energy (B=6.2×10?2 andK=2.16×10?5, respectively), is applied universally to wide ranges of wind waves from those in a wind-wave tunnel to fully developed sea in the open ocean. “The three-second power law for wind waves of simple spectrum”, and a few relations as the lemmas, are derived, such that the mean surface transport due to the orbital motion of wind waves is always proportional to the friction velocity in wind, and that the steepness is inversely proportional to the root of the wave age. It is also derived that the portion of wind stress which directly enters the wind waves decreases exponentially with increasing wave age and is 7.5 % of the total wind stress for very young waves. Also, equations are presented as to the increase of momentum of drift current, and as to the supply of turbulent energy by wind waves into the upper ocean.  相似文献   

6.
We study the processes of global self-regulation of Earth’s biota (GAIA-theory) by applying the method of adaptive balance of causes proposed by the authors. By using, as an example, the Daisy World model constructed by this method, we reveal the phenomenon of preservation of the mean temperature of Earth’s surface due to the presence of the vegetation cover. We develop an integral model of global natural, social, and economic processes in which the World Ocean is one of the factors regulating the amount of greenhouse gases in the atmosphere. The decrease in the amount of greenhouse gases in the atmosphere caused by the GAIA-effects increases the number of hurricanes and floods on the Earth. As a result, the levels of ecological and social hazards for the mankind become much higher. To eliminate these threats, it is necessary to intensify the processes of self-organization of the society realized via the improvement of education, development of science, and global regulation of the competition for natural resources. We present the results of numerical experiments performed by using the model demonstrating possible scenarios of global development with regard for the processes of self-organization of the society. __________ Translated From Morskoi Gidrofizicheskii Zhurnal, No. 3, Pp. 62–80, May–June, 2007.  相似文献   

7.
We consider an algorithm of prediction of nonstationary time series based on the method of analogs. Since the exhaustion of a great number of versions is required for the adjustment of the parameters of the optimal prognostic model, we describe a genetic algorithm used in this case. We consider several procedures of construction of prognostic models. The numerical results are used to choose the procedure guaranteeing the minimum mean square error. The parameters of the model affecting the quality of predictions are determined. The proposed method is tested by using the reanalysis data (NCEP/NCAR project) on the anomalies of the monthly average surface air temperature for 58 yr. The results of predictions are compared with the estimates obtained by the linear regression method. It is shown that the method of analogs gives satisfactory results even in the cases where the regression methods lead to errors equal to the variance of predicted series. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 70–80, July–August, 2007.  相似文献   

8.
The lake Hunnebotn (A=1 km2, zmax=11 m) has become separated from the sea by isostasis, but a 1.5-m-deep channel is held open by periodic dredging. Water exchange is minor due to the small tidal range (21 cm) and the length of the channel (1.8 km), but there may be an inflow of seawater at spring tides. The terrestrial watershed runoff may be fertilized by sewage and agricultural runoff despite some measures taken to prevent this. Historical and new records of biological communities indicate variations in sensitivity to different phases of the isolation and eutrophication process. The native oyster was most sensitive and disappeared first. Later, the eelgrass disappeared possibly due to overgrowth by epiphytic algae, and finally there was a massive littoral–sublittoral invasion of green algae. The lake should not be left in this condition, for aesthetic reasons and because marine inlets and eutrophic brackish water may serve as refugia for spore populations of toxic microalgae. Improving surface water quality will require better control of anthropogenic sources, but bursts and leaks of nutrients from the anoxic monimolimnion cannot be controlled.  相似文献   

9.
As follows from the statement of the Third Official Solar Cycle 24 Prediction Panel created by the National Aeronautics and Space Administration (NASA), the National Oceanic and Atmospheric Administration (NOAA), and the International Space Environment Service (ISES) based on the results of an analysis of many solar cycle 24 predictions, there has been no consensus on the amplitude and time of the maximum. There are two different scenarios: 90 units and August 2012 or 140 units and October 2011. The aim of our study is to revise the solar cycle 24 predictions by a comparative analysis of data obtained by three different methods: the singular spectral method, the nonlinear neural-based method, and the precursor method. As a precursor for solar cycle 24, we used the dynamics of the solar magnetic fields forming solar spots with Wolf numbers Rz. According to the prediction on the basis of the neural-based approach, it was established that the maximum of solar cycle 24 is expected to be 70. The precursor method predicted 50 units for the amplitude and April of 2012 for the time of the maximum. In view of the fact that the data used in the precursor method were averaged over 4.4 years, the amplitude of the maximum can be 20–30% larger (i.e., around 60–70 units), which is close to the values predicted by the neural-based method. The protracted minimum of solar cycle 23 and predicted low values of the maximum of solar cycle 24 are reminiscent of the historical Dalton minimum.  相似文献   

10.
2009年“04·15”风暴潮过程预报及成因分析   总被引:1,自引:1,他引:0  
王世彬 《海洋预报》2010,27(3):35-39
作者利用本站气象观测和常规水文、气象观测资料,对诱发本次风暴潮的天气系统、风场结构及其与天文潮汐之间的关系进行了分析。分析结果表明(:1)通过人工气象观测,运用相似法,来判断本次风暴潮过程的变化规律;(2)稳定的500 hPa环流形势和"北高南低"气压场配置是形成沧州沿海向岸大风的必要前提;(3)强烈持久的向岸大风,是造成风暴增水的主要因素;(4)加强观测、科学预报是提高预报准确率的必要手段。  相似文献   

11.
We studied the cyclic structure of the earlywood ring width and maximum density of larch and spruce (International Tree-Ring Data Bank) at the northern treeline in European Russia. On the basis of correlation analyses, local chronologies are combined into seven regional ones. The chronologies of maximum density correlate positively with summer (May–August) temperature. The response functions for the earlywood ring width are chaotic. However, a wavelet analysis of instrumental cold-period (October–April) precipitation series and regional earlywood chronologies shows a similarity in their cyclic pattern. On the basis of a wavelet analysis, it was found that the chronologies of the western and northern regions of European Russia have a similar cyclic structure over the last 300 years, while the Ural chronologies differ from them in some respects. The long-term (40–100 years) variations dominate in the earlywood chronologies, whereas the chronologies of maximum density also contain short-term (5–20 years) variations. The 100- and 11-year cycles, which are probably modulated by solar activity, are detectable in all regional chronologies of earlywood width and maximum density. Cycles with periods of 40, 20–22, and 5 years in the tree-ring chronologies are most likely triggered by the North Atlantic Oscillation, which has a similar cyclic structure.  相似文献   

12.
13.
Stable oscillations of heliogeophysical and other natural processes are generated within the solar system (SS) by interactions between the gravitational fields of the Sun, planets, and their satellites. The resonant periods of the SS are well described by a geometrical progression similar to a sound series with 32 notes in an octave. A comparison of the members of this geometrical progression to the orbital and rotational periods of the planets and the Moon and to the orbital periods of Jupiter’s satellites shows that the discovered regular pattern in the distribution of the motion periods of SS bodies holds with a 95% probability. Numerous natural periods of solar activity, interplanetary magnetic fields, the Earth’s magnetic field and rotational speed, movement of the Earth’s poles, seismic activity, and other terrestrial processes in the range of 10−4–106 years are also consistent with the members of this geometrical progression. Heliogeophysical oscillations have a common external origin, and their periods often coincide with one another. The amplitudes of the oscillations of terrestrial processes depend on the oscillations in solar activity, lunar-solar tidal forces, and the Earth’s rotational speed, and on the interactions of geophysical processes. The existence of common external periods makes it possible to find significant correlations between terrestrial processes that appear to have no cause and effect relationships, e.g., between global air temperatures and magnitudes of regional earthquakes over a 600-year interval. These correlations testify to the influence of changes in the Earth’s rotational speed on tectonic and climatic processes and provide additional proof for the feasibility of the harmonic model of Northern Hemisphere temperatures. The parameters of stable oscillations that are components of global seismicity harmonic models and those of air temperatures and other natural processes are found from the respective simulated or observed time series. These models permit long-term forecasts of terrestrial and solar processes. The paper gives examples of successful forecasts of global seismicity in 2005–2010 and hazardous events of various origin in 1986, 1995, 2005, 2008, and 2010. Hazardous events are expected to intensify in 2011/2012, 2016/2017, 2024, and 2028/2029. The next economic crisis is expected in 2029 ± 1.  相似文献   

14.
Water exchange between a semiclosed bay and the adjacent sea, and its relation to atmospheric forcing is examined from a field experiment undertaken in the Bay of Kaštela (Adriatic Sea, Yugoslavia). Four ‘Aanderaa’ RCM4 current meters were attached on a single mooring in a 45 m deep inlet of the Bay for about two months. Water samples were taken for phytoplankton and bacteria determination at several additional stations. Salinity, temperature measurements, and determinations of the Secchi-disc depth were also made. Samples were taken approximately each week during the current measurement period so as to resolve the synoptic time scale. In the first part of the current measurement period the water was stratified, while in the second part the entire water column became vertically mixed after a strong wind event. During stratified conditions kinetic energy was at a maximum in the intermediate layer, while during homogeneous conditions the kinetic energy was trapped mainly in the bottom layer. Vertical modal structure of the current field showed that during homogeneous conditions wind induced surface flow was 180° out of phase with respect to the bottom flow. The current reversal appeared at the depth between 8 and 20 m. Under stratified conditions the surface flow was in phase with the bottom flow and water entered the Bay on one side of the inlet in the whole water column and left on the other side. These water exchange structures were reflected in the horizontal distribution of density, bacteria, Secchi-disc data and phytoplankton composition.  相似文献   

15.
胜利油田经过近40多年的勘探,按照国内外勘探程度划分的标准,其主力探区济阳坳陷目前已处于成熟勘探程度,全面进入隐蔽油气藏勘探阶段,勘探难度越来越大。尽管济阳坳陷探井成功率保持较高的水平,但仍有50%左右的探井落空或低效。根据“失利”探井定义,从生、储、盖、图、运、保等6种油气成藏控制因素出发,参考济阳坳陷石油地质特点和近几年的勘探经验,主要从圈闭是否有效、储层是否存在、输导体系是否发育、油气充满程度等4个方面进行失利探井地质原因分析,建立起成熟探区探井失利地质原因分析方法。总结了济阳坳陷“十五”以来主要增储目标,即:砂砾岩体、浊积砂体、滩坝砂体、河道砂体等储层类型的失利地质原因。在明确上述目标类型最主要勘探风险的基础上,提出了勘探攻关重点及风险规避建议。  相似文献   

16.
In this paper, the hazard of adverse heat effect on permafrost soil as a result of viscous oil production in the Far North is studied with the method of thermocompression supply of superheated water steam to the oil-bearing layer. It is found that, due to the divergent nature of heat transfer and convective complex movement of air in the space between the tubing and the casing, the temperature of the latter in the area of load-bearing elements heated to 130°C is about 70°C. The heterogeneity of the temperature field is leveled up to 4–5% at a distance of 400–420 mm from the axis of the tubing. The thickness of the melting layer of ground ice within 90 days of operation of the tubing depends on the percentage of water-filled pores in the soil. With the minimum (10%) percentage of water-filled pores in the soil layer, the thickness of the ground ice melting layer for 90 days of operation of the tubing does not exceed 2.6 m.  相似文献   

17.
刘亮  曹东  吴姗姗  徐伟 《海洋通报》2012,31(1):26-31
以无居民海岛大娥眉岭、小娥眉岭、背风墩为例,分析了这3个海岛的海洋自然资源条件,并建立海洋环境效应评价方法和指标体系。应用层次分析法确定指标权重,应用灰度分析方法对3个海岛进行了综合评价和对比,为海岛的开发利用和可持续发展决策提供基础依据。根据分析,认为制约无居民海岛开发的主要自然资源因素是离岸距离和淡水资源。  相似文献   

18.
A self adaptive three-dimensional baroclinic model is designed. A horizontal temperature gradient is used to control the grid size, which can improve computational precision in the fronts without inordinately increasing computation in the whole area. A simulation of the development and disappearance of the front in the Huanghai Sea is conducted with this model. Simulations of temperature distribution throughout the year are also conducted. The computational result agrees well with the observation.  相似文献   

19.
大弹涂鱼自然种群遗传多样性的RAPD分析   总被引:12,自引:1,他引:12  
2002年9月以采自浙江宁海三门湾海区的大弹涂鱼(Boleophthalmus pectinirostris L.)为材料,对大弹涂鱼自然种群的遗传多样性进行随机扩增多态DNA(RAPD)分析,20个引物共扩增出100个DNA片段,多态位点比例(P)为21%,任意两个个体间遗传相似度(F)最大为0.9938,最小为0.9239,平均为0.9645。任意两个个体间的遗传距离(D)最大为0.0761,最小为0.0062,绝大多数为0.02000~0.0500;大弹涂鱼自然种群的平均杂合度(He)为0.2018,D平均值为0.0355;Shannon多样性指数(Ho)和Shannon多样性值(H)分别为5.918和0.0592。研究结果表明大弹涂鱼的遗传多样性水平比较低,应加强大弹涂鱼种质资源的保护。  相似文献   

20.
This research quantifies the rate and volume of oil and gas released from two natural seep sites in the Gulf of Mexico: lease blocks GC600 (1200 m depth) and MC118 (850 m depth). Our objectives were to determine variability in release rates and bubble size at five individual vents and to investigate the effects of tidal fluctuations on bubble release. Observations with autonomous video cameras captured the formation of individual bubbles as they were released through partially exposed deposits of gas hydrate. Image processing techniques determined bubble type (oily, gaseous, and mixed: oily and gaseous), size distribution, release rate, and temporal variations (observation intervals ranged from 3 h to 26 d). A semi-automatic bubble counting algorithm was developed to analyze bubble count and release rates from video data. This method is suitable for discrete vents with small bubble streams commonly seen at seeps and is adaptable to multiple in situ set-ups. Two vents at GC600 (Birthday Candles 1 and Birthday Candles 2) were analyzed. They released oily bubbles with an average diameter of 5.0 mm at a rate of 4.7 bubbles s−1, and 1.3 bubbles s−1, respectively. Approximately 1 km away, within the GC600 seep site, two more vents (Mega Plume 1 and Mega Plume 2) were analyzed. These vents released a mixture of oily and gaseous bubbles with an average diameter of 3.9 mm at a rate of 49 bubbles s−1, and 81 bubbles s−1, respectively. The fifth vent at MC118 (Rudyville) released gaseous bubbles with an average diameter of 3.0 mm at a rate of 127 bubbles s−1. Pressure records at Mega Plume and Rudyville showed a diurnal tidal cycle (24.5 h). Rudyville was the only vent that demonstrated any positive correlation (ρ = 0.60) to the 24.5 h diurnal tidal cycle. However, these observations were not conclusive regarding tidal effects on bubble release.  相似文献   

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