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101.
本文基于FVCOM-SWAVE耦合模型,以双台风"苏拉"和"达维"的台风过程为例,研究了台风过程中海浪和海温的变化,通过与高度计和Argo资料的对比,发现耦合模型能较准确的模拟出有效波高和海表面温度。由于双台风风场相互作用,风场结构和最大风速位置发生改变,影响着有效波高的分布,台风"苏拉"产生的最大有效波高位于台风后侧。海表面温度的降低与风场、浪场分布密切相关,强风强浪处的降温现象更明显,"苏拉"产生的降温区域位于路径附近,"达维"产生的降温区域位于路径右侧。台风对海表面温度的降低与初始的混合层厚度、温跃层强度存在相关性,具体表现为初始的混合层越薄、温跃层强度越大,降温越明显。  相似文献   
102.
Abstract

Abstract The impact of climate change is projected to have different effects within and between countries. Information about such change is required at global, regional and basin scales for a variety of purposes. An investigation was carried out to identify trends in temperature time series of 125 stations distributed over the whole of India. The non-parametric Mann-Kendall test was applied to detect monotonic trends in annual average and seasonal temperatures. Three variables related to temperature, viz. mean, mean maximum and mean minimum, were considered for analysis on both an annual and a seasonal basis. Each year was divided into four principal seasons, viz. winter, pre-monsoon, monsoon and post-monsoon. The percentages of significant trends obtained for each parameter in the different seasons are presented. Temperature anomalies are plotted, and it is observed that annual mean temperature, mean maximum temperature and mean minimum temperature have increased at the rate of 0.42, 0.92 and 0.09°C (100 year)-1, respectively. On a regional basis, stations of southern and western India show a rising trend of 1.06 and 0.36°C (100 year)-1, respectively, while stations of the north Indian plains show a falling trend of –0.38°C (100 year)-1. The seasonal mean temperature has increased by 0.94°C (100 year)-1 for the post-monsoon season and by 1.1°C (100 year)-1 for the winter season.  相似文献   
103.
海洋灾害造成贝类养殖损失的价值评估是海洋科学与水产科学交叉产生的新科学命题,同时也是渔业经济学与保险价值核算的难题。本文从海浪导致贻贝脱落致灾的角度展开研究,采用第三代海浪模型SWAN,以嵊泗海域作为研究区,通过P-Ⅲ曲线拟合、波高重现期分析,定量研究了台风期间贻贝脱落率与有效波高之间的相关性。研究表明,当有效波高达到3 m时,贻贝开始出现脱落的可能性较大;当有效波高超过9 m时,出现脱落率达100%的可能性较大。研究结果可作为海洋水产养殖损失保险理赔的参考。  相似文献   
104.
The multi-scale characteristics of wave significant height (Hss) in eastern China seas were revealed by multi-scale wavelet analysis. In order to understand the relation between wave and wind, the TOPEX/Poseidon measurements of Hs and wind speed were analyzed. The result showed that Hs and wind speed change in multi-scale at one-, two-month, half-, one- and two-year cycles. But in a larger time scale, the variations in Hs and wind speed are different. Hs has a five-year cycle similar to the cycle of ENSO variation, while the wind speed has no such cycle. In the time domain, the correlation between Hs and ENSO is unclear.  相似文献   
105.
台风浪的研究对于船舶航行、避风以及港口、海洋和近岸建筑物的安全有着重要的现实意义.本文基于考虑波浪折射、底部损耗及波浪破碎等的波谱模型,在充分考虑风能量输入、白帽耗散、水深诱导以及波-波间的非线性相互作用等物理过程,对袭击广东省和福建省沿海的0601号强台风“珍珠”引起的台风浪过程进行了数值模拟计算,计算结果与云澳海洋...  相似文献   
106.
东中国海海浪数值模式的研究   总被引:7,自引:1,他引:7  
为建立适应东中国海的海浪数值模式,主要基于目前广泛使用的WAVEWATCHⅡⅠ海浪数值模式进行东中国海海域的海浪数值模拟。以NCEP和NCEP与QSCAT的混合风场资料为输入,模拟了两个时间段的东中国海海域的海面风浪场。选取的两个有实测资料的输出点分别在渤海和东海。从所得结果来看,使用NCEP与QSCAT混合风场模拟的东海观测点处的波高和风场的观测值和模拟值符合的较好;利用1998年相应时间段的NCEP风场模拟的上述两点结果与实测比较也是可以接受的。研究结果说明,在目前情况下,运用NCEP与QSCAT混合风场建立统一的东中国海海浪数值预报模式是可行的,同时为东中国海波气候学研究及海洋大气耦合作用研究奠定了模式基础。  相似文献   
107.
利用吕梁高海拔山区代表站岚县气象观测站1957年-2010年的气温、年(季)降水量、年日照时数、年蒸发量等地面气象资料,应用线性趋势函数分析法进行了统计分析。结果表明:岚县年平均气温呈上升趋势,冬季增温最显著;降水量的变化总体上呈减少趋势,降水量的减少主要是夏季降水减少所引起。年日照时数有明显的下降趋势,年蒸发量则缓慢增加。  相似文献   
108.
Using the wave model WAVEWATCH III(WW3), we simulated the generation and propagation of typhoon waves in the South China Sea and adjacent areas during the passage of typhoon Nesat(2011). In the domain 100°–145°E and 0°–35°N, the model was forced by the cross-calibrated multi-platform(CCMP) wind fi elds of September 15 to October 5, 2011. We then validated the simulation results against wave radar data observed from an oil platform and altimeter data from the Jason-2 satellite. The simulated waves were characterized by fi ve points along track using the Spectrum Integration Method(SIM) and the Spectrum Partitioning Method(SPM), by which wind sea and swell components of the 1D and 2D wave spectra are separated. There was reasonable agreement between the model results and observations, although the WW3 wave model may underestimate swell wave height. Signifi cant wave heights are large along the typhoon track and are noticeably greater on the right of the track than on the left. Swells from the east are largely unable to enter the South China Sea because of the obstruction due to the Philippine Islands. During the initial stage and later period of the typhoon, swells at the fi ve points were generated by the propagation of waves that were created by typhoons Haitang and Nalgae. Of the two methods, the 2D SPM method is more accurate than the 1D SIM which overestimates the separation frequency under low winds, but the SIM method is more convenient because it does not require wind speed and wave direction. When the typhoon left the area, the wind sea fractions decreased rapidly. Under similar wind conditions, the points located in the South China Sea are affected less than those points situated in the open sea because of the infl uence of the complex internal topography of the South China Sea. The results reveal the characteristic wind sea and swell features of the South China Sea and adjacent areas in response to typhoon Nesat, and provide a reference for swell forecasting and offshore structural designs.  相似文献   
109.
SARAL carried onboard a radar altimeter that provides very precise measurements of the sea surface height (SSH). Like other altimetric missions, SARAL carries a passive microwave radiometer (PMR) for wet tropospheric correction to SSH. In the present study, new algorithms are developed for the retrieval of cloud liquid water (CLW) and total precipitable water vapor (TPW) over the global oceans from PMR measurements of the brightness temperatures. A radiative transfer and genetic algorithm based retrieval scheme is proposed for the estimation of CLW and TPW from SARAL PMR. The comparisons of CLW from PMR with independent measurements from GPM-GMI and SSMIS within and outside ±40° latitudes show correlation (R) of 0.86 and 0.83, bias of 0.7 and ?3.61?mg/cm2, and root mean square error (RMSE) of 8.42 and 8.07?mg/cm2, respectively. Similarly, TPW from PMR with GPM-GMI and SSMIS show R of 0.99 and 0.98, bias of ?0.04 and ?0.03?g/cm2 and RMSE of 0.17 and 0.17?g/cm2, respectively. The retrieval accuracy of CLW and TPW from the new algorithms is compared with these parameters provided in the SARAL geophysical data records as finished products, which showed substantial improvement in the quality of the parameters from the new algorithm.  相似文献   
110.
Significant wave height is an important criterion in designing coastal and offshore structures. Based on the orthogonality principle, the linear mean square estimation method is applied to calculate significant wave height in this paper. Twenty-eight-year time series of wave data collected from three ocean buoys near San Francisco along the California coast are analyzed. It is proved theoretically that the computation error will be reduced by using as many measured data as possible for the calculation of significant wave height. Measured significant wave height at one buoy location is compared with the calculated value based on the data from two other adjacent buoys. The results indicate that the linear mean square estimation method can be well applied to the calculation and prediction of significant wave height in coastal regions.  相似文献   
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