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1.
We present the results of the analysis of the phase relationships between the quasi-decadal variations (QDVs) (in the range from 8 to 13 years) in the total ozone content (TOC) at the Arosa station for 1932–2012 and a number of meteorological parameters: monthly mean values of temperature, meridional and zonal components of wind velocity, and geopotential heights for isobaric surfaces in the layer of 10–925 hPa over the Arosa station using the Fourier methods and composite and cross-wavelet analysis. It has been shown that the phase relationships of the QDVs in the TOC and meteorological parameters with an 11-year cycle of solar activity change in time and height; starting with cycle 24 of solar activity (2008–2010), the variations in the TOC and a number of meteorological parameters occur in almost counter phase with the variations in solar activity. The periods of the maximum growth rate of the temperature at isobaric surfaces 50–100 hPa nearly correspond to the TOC’s maximum periods, and the periods of the maximum temperature correspond the periods of the decrease of the peak TOC rate. The highest correlation coefficients between the meridional wind velocity and temperature are observed at 50 hPa at positive and negative delays of ~27 months. The times of the maxima (minima) of the QDVs in the meridional wind velocity nearly correspond to the periods of the maximum amplification (attenuation) rate of the temperature of the QDVs. The QDVs in the geopotential heights of isobaric surfaces fall behind the variations in the TOC by an average of 1.5 years everywhere except in the lower troposphere. In general, the periods of variations in the TOC and meteorological parameters in the range of 8–13 years are smaller than the period of variations in the level of solar activity.  相似文献   

2.
A detailed analysis of climatic trends in the longitudinally averaged temperature, zonal wind velocity, and activity of a stationary planetary wave with the zonal wave number 1 (SPW1) is made for January. The results of analysis indicate that marked climatic temperature variations having opposite signs in the low and high latitudes are observed. These variations cause the relevant variations in the intensity and arrangement of maxima of tropospheric jet flows and, thereby, are responsible for changes in SPW1 propagation conditions. SPW1 propagation from the troposphere into the upper atmosphere is calculated with a linearized model by using the distributions of zonal mean flow that are characteristic of the 1960s and the early 21st century. These calculations indicate that, over the past 40 years, the propagation conditions have improved “on average” and the calculated SPW1 amplitude in the stratosphere and mesosphere of the winter hemisphere has increased substantially. Analysis of the amplitudes of the zonal wind velocity for SPW1 that were obtained from the NCEP/NCAR data is consistent with the results of simulation and shows that some enhancement of SPW1 activity in the lower stratosphere has been actually observed in recent years. These variations in the amplitudes are also accompanied by the enhancement of SPW1 interannual variability.  相似文献   

3.
系统地分析了137°E断面温、盐度的多年变化,主要结果为:(1)137°E断面100m层温度,在低纬度海域于某些年份出现异常低温,此现象可能与厄尔尼诺事件有关;指出棉兰老冷涡的存在是造成该断面于6°~8°N附近出现低温的主要原因。(2)厄尔尼诺期间,冬季137°E断面上28℃等温线所在纬度小于其多年平均值。(3)冬季137°E断面上次表层高盐水可划分为强型、次强型、中等型和弱型4种类型。  相似文献   

4.
The results of long-term (1980–2003) systematic measurements of the total ozone content at the Issyk Kul station (42.6° N, 77.0° E; 1650 m above sea level) are presented. The statistical characteristics and spectral structure of variations in the total ozone and the main tendencies of its temporal variability are determined. It is found that the total ozone content decreased in 1980–2003 at an average rate of (?1.29±0.08) DU/yr. The results of Fourier and wavelet analyses have shown that only oscillations with periods of 12, 27–29, and 102–105 months are rather stable and can be represented as harmonic oscillations. Oscillations with periods shorter than six months have the character of periodically arising pulsations. Among these, oscillations with periods of 27–29 and 34–37 days can be distinguished. It is noted that the spectral-temporal structure of variations in the total ozone content obtained from ground-based measurements at the Issyk Kul station is in good agreement with the corresponding structure obtained from TOMS satellite measurements.  相似文献   

5.
This paper analyzes atmospheric ozone variability at different altitudes over St. Petersburg for the period 2009–2014 on the basis of surface observations at the Peterhof station, satellite measurements with an SBUV instrument, and numerical simulations. Simulation data on temperature, wind velocity, humidity, and surface pressure are taken from the MERRA reanalysis database. Based on ozone measurements, numerical modeling, and reanalysis data, characteristics of ozone seasonal and interannual changes are identified; the role of photochemical and dynamic factors in ozone variations is estimated.  相似文献   

6.
北黄海獐子岛海域浮游动物群落年际变化   总被引:1,自引:0,他引:1  
本文比较了海洋普查期间(1959年1-12月)和2009-2010年獐子岛海域附近站位的浮游动物的种类组成、优势种、丰度、生物多样性,结果显示,北黄海区域浮游动物群落物种组成未发生较大的变化,在獐子岛海域以及整个北黄海,中华哲水蚤和强壮箭虫的优势种地位没有发生变化,细足法虫戎也一直出现且为冬春季的优势种;太平洋磷虾在2009-2010年獐子岛海域虽然全年均有出现,但是全年均不是优势种,而在1959年的獐子岛海域,作为优势种出现在4月和11月;1959年与2009年相较,腹针胸刺水蚤在春夏季优势种的地位被沃氏纺锤水蚤所取代。2009年浮游动物丰度(131.26 ind/m3)比1959年(78.90 ind/m3)高;浮游动物多样性指数(H')均在夏秋季高于冬春季节,且年平均多样性指数也有所提高。  相似文献   

7.
The ERA40 and NCEP/NCAR data over 1958–1998 were used to estimate the sensitivity of amplitude-phase characteristics (APCs) of the annual cycle (AC) of the surface air temperature (SAT) T s. The results were compared with outputs of the ECHAM4/OPYC3, HadCM3, and INM RAS general circulation models and the IAP RAS climate model of intermediate complexity, which were run with variations in greenhouse gases and sulfate aerosol specified over 1860–2100. The analysis was performed in terms of the linear regression coefficients b of SAT AC APCs on the local annual mean temperature and in terms of the sensitivity characteristic D = br 2, which takes into account not only the linear regression coefficient but also its statistical significance (via the correlation coefficient r). The reanalysis data were used to reveal the features of the tendencies of change in the SAT AC APCs in various regions, including areas near the snow-ice boundary, storm-track ocean regions, large desert areas, and the tropical Pacific. These results agree with earlier observations. The model computations are in fairly good agreement with the reanalysis data in regions of statistically significant variations in SAT AC APCs. The differences between individual models and the reanalysis data can be explained, in particular, in terms of the features of the sea-ice schemes used in the models. Over the land in the middle and high latitudes of the Northern Hemisphere, the absolute values of D for the fall phase time and the interval of exceeding exhibit a positive intermodel correlation with the absolute value of D for the annual-harmonic amplitude. Over the ocean, the models reproducing larger (in modulus) sensitivity parameters of the SAT annual-harmonic amplitude are generally characterized by larger (in modulus) negative sensitivity values of the semiannual-harmonic amplitude T s, 2, especially at latitudes characteristic of the sea-ice boundary. In contrast to the averaged fields of AC APCs and their interannual standard deviations, the sensitivity parameters of the SAT AC APCs on a regional scale vary noticeably for various types of anthropogenic forcing.  相似文献   

8.
根据1973年至2016年黄海沿岸风、平均海平面气压与气温观测资料,采用旋转经验正交函数(REOF)、调和分析和延迟相关分析等方法,研究了黄海月平均风应力、风速、平均海平面气压、气温场季节与年际变化时空模态.月平均风应力、风速场主要有4种时空模态,风应力模态空间分量分布与风速模态不完全相同,风应力、风速模态季节周期分量多数为不稳定,风应力、风速场强度年际变化显著线性减弱,对黄海环流以及物理、化学要素场季节与年际变化有显著影响.月平均气压、气温场季节循环与年际变化主要有2种时空模态,气压、气温模态季节周期分量的位相均为准稳定季节变化;振幅为不稳定季节变化.气压模态为准平衡态年际变化,大尺度气压系统季节与年际变化是黄海气压场模态的主要影响因素.气温模态为显著线性升温趋势年际变化,海气、陆气热交换作用对黄海气温场模态季节与年际变化有显著影响.  相似文献   

9.
The relationship between the intensity of surface wind waves and near-water wind is analyzed. The data of measuring wind waves and near-water wind under natural conditions in the Black Sea (July 2004) and Norwegian Sea (June 2003, 16th cruise of the R/V Akademik Sergei Vavilov) are used. A phenomenon of negative correlations has been found between the intensity of wind waves and near-water wind in regions of substantial restructuring of wind waves in the field of inhomogeneous flows: wind-wave amplification during wind decay and vice versa. Examples of such observations are presented, a theoretical model is constructed for the observed phenomenon, and a good agreement is obtained between theory and experiment.  相似文献   

10.
在Gaussian波场基础上,推导出以P-M谱和平均JONSWAP谱代表的充分成长和有限风区的深水风浪平均波长与平均波周期之间的关系为.推导中运用了Rice跨零点问题的解并通过滑动时间平均技术估计4阶谱矩.在风浪水槽进行了实验,实验结果与有限风区下推导出的关系相比较,符合较好.  相似文献   

11.
通过统计方法利用一套海洋同化数据分析了热带太平洋次表层的盐度变化特征.结果表明次表层盐度的年际变化与ENSO相关,且次表层盐度信号区域呈东西方向“跷跷板”的分布.对影响这些次表层的盐度信号区域平均的纬向平流、经向平流、垂直运动和淡水通量异常等因素进行了分析,并且与影响表层盐度年际变化模态的影响因素差异进行了比较,结果表明,纬向平流的异常对表层盐度的异常变化影响较大,而对次表层盐度异常有较大影响的是海水的垂直运动异常.  相似文献   

12.
渤海海冰的年际和年代际变化特征与机理   总被引:1,自引:0,他引:1  
根据1951-2013年间的渤海冰情等级资料,利用最大熵谱分析、相关分析和合成分析等方法,研究了渤海冰情等级的年际和年代际变化特征,探讨了局地气候、大气环流、ENSO(El Nio-Southern Oscillation)和太平洋年代际振荡(PDO)对海冰的影响。结果表明,渤海海冰具有明显的年际和年代际变化特征,并在1972年前后发生了一次由重到轻的气候跃变,在跃变后冰情较跃变前平均降低了0.7级。相关分析与合成分析结果显示,渤海冰情的年际变化除受局地气候的影响外,还受西太平洋副热带高压(副高)、极涡和欧亚环流的共同调控,特别在1972年以后,秋季副高、冬季欧亚和亚洲纬向环流对渤海冰情的年际变化均有重要影响,可作为渤海海冰预报的重要因子,而春季PDO、ENSO、冬季副高及欧亚和亚洲经向环流则是渤海冰情年代际变化的影响因素。  相似文献   

13.
Models for global mean values of temperature; air, ozone, and water-vapor concentrations; and zonal and meridional winds at heights of 0–45 km are developed and constructed from data of the European ERA-40 and Era Interim databases over the period 1958–2007. An analysis of the time series consists of the decomposition of parameter values into harmonic, trend, and pulsation components. A comparative analysis of these models is performed, and a relationship between the global mean ozone concentration and solar activity is detected. A hypothesis about the physical mechanism for the relationship between the total ozone concentration (TOC) and solar activity is proposed.  相似文献   

14.
A 30 km-range reciprocal sound transmission experiment was carried out on the line connecting Honshu and Shikoku (the first and fourth biggest main Japanese islands, respectively) in the central part (Aki-nada) of the Seto Inland Sea, Japan, during March–May 2010 to measure the mean current and temperature variations over the sea. The range-averaged current along the sound transmission line was estimated to have a mean and standard deviation of (3.8–4.4) ± (1.7–1.8) cm/s after converting the travel time difference data into currents, including a fortnightly tidal variation in the range of ±30 cm/s. The positive mean current implies slow water movement from the west to east through Aki-nada. The range-averaged speed of sound was estimated by converting from the mean travel time or one-way travel time into the speed of sound, and further converted into temperature for fixed values of salinity and depth, according to the standard speed of sound formula. Besides the precise measurement (to an accuracy of 0.01°C) of semidiurnal and diurnal tidal variations and seasonal warming, the temperature data showed periodic variations with periods of 7.0 and 21.1 days that had never been observed in Aki-nada before. This study suggests that reciprocal sound transmission is a powerful technique for the long-term accurate measurement of mean current and temperature variations in coastal and inland seas.  相似文献   

15.
Interannual salinity variations in the Tsushima Strait are investigated on the basis of historical hydrographic data. The EOF analysis revealed that the most dominant mode is the in-phase salinity variation between the eastern and western channels. The time coefficients of the EOF first mode in summer show a negative correlation with the Changjiang discharge, which indicates that salinity in the Tsushima Strait tends to decrease over summer, related to a large discharge of the Changjiang. The eigenvectors of the first mode are larger in the eastern channel than those in the western channel, though the low salinity water mainly flows through the western channel. This is because the low salinity water spreads into the eastern channel as well as the western channel over summers with a large discharge of the Changjiang. The out-of-phase salinity variation between the channels is extracted as the EOF second mode; this is the predominant variation in the western channel. The time coefficients of the second mode in summer show no significant correlations to the volume transports through the western channel and the transport differences between channels. A relationship between the EOF second mode and variations in the wind stress over the East China Sea is suggested.  相似文献   

16.
17.
Interannual-to-decadal variations in the subtropical countercurrent (STCC) and low potential vorticity (PV) water and their relations in the North Pacific Ocean are investigated on the basis of a 60-year-long hindcast integration of an eddy-resolving ocean general circulation model. Although vertically coherent variations are dominant for STCC interannual variability, a correlation analysis shows that an intensified STCC vertical shear accompanies lower PV than usual to the north on 25.5- to 26.1-σθ isopycnal surfaces, and intensified meridional density gradient in subsurface layers, consistent with Kubokawa’s theory (J Phys Oceanogr 29:1314–1333, 1999). The low-PV signals appear at least 2 years before peaks of STCC, propagating southwestward from the subduction region.  相似文献   

18.
南黄海浮游动物主要种类数量分布年间比较   总被引:3,自引:0,他引:3  
陈峻峰  左涛  王秀霞 《海洋学报》2013,35(6):195-203
分析对比1959年、1982年、1998-2000年以及2007-2010年4个不同时期南黄海中部(34.25°~37.45°N,122.00°~124.00°E)浮游动物主要优势种中华哲水蚤(Calanus sinicus)、太平洋磷虾(Euphausia pacifica)和强壮箭虫(Sagitta crassa)数量时空变化及其与温度、盐度和太平洋年代际震荡指数(Pacific Decadal Oscillation,PDO)变动的关系。结果显示,温度可能对中华哲水蚤和太平洋磷虾数量分布影响较大;强壮箭虫则受盐度影响较大。PDO暖位相时期中华哲水蚤和太平洋磷虾数量显著低于冷位相时期,强壮箭虫则相反。中华哲水蚤和太平洋磷虾丰度与提前3个月PDO值呈显著正相关,强壮箭虫丰度仅与当月PDO值呈显著正相关。  相似文献   

19.
20.
Ozone total column (OTC) measurements made in 2009–2012 near St. Petersburg by a Fourier Transform Infrared (FTIR) spectrometer (Peterhof, St. Petersburg State University (SPbSU)), an M-124 filter ozonometer, and a Dobson spectrophotometer (Voeikovo, MGO), as well as measurements made by a spectrometer ozone monitoring instrument (OMI) (onboard the AURA satellite) have been analyzed and compared. Comparisons have been performed both between ensembles of ground-based measurement data, as well as between ground-based and satellite data. It has been shown that the standard deviation for all devices is 2.5–4.5%; here, the FTIR and Dobson instruments measuring the direct sun are in better agreement with OMI than the M-124 ozonometer measuring the zenith-scattered solar radiation as well. A seasonal cycle in discrepancy with amplitude of 1.5% has been detected between two series of OTC measurements made by M-124 and OMI instruments for a total of 850 days. In fall and winter, the ground-based measurements underestimate the OTC values in comparison with satellite data; in spring and summer, the situation is reversed: ground-based data overestimate the OTC values. Also, it has been revealed that FTIR measurements systematically overestimate the OTC values in comparison with other instruments: from 1.4% (for Dobson) to 3.4% (for OMI). Taking into account the spatial and temporal discrepancy of independent ensembles of measurements and an analysis of standard deviations between ground-based and satellite measurement data, the FTIR spectrometer (SPbSU) can be recommended for OTC satellite data validation.  相似文献   

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