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141.
SARAL/AltiKa surface wind speed (WS) and significant wave height (SWH) measurements are monitored and validated against operational European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric and wave model results in addition to available in-situ observations to access their suitability for various applications, especially SWH data assimilation. The quality of SWH is very high while that of WS is very good except for an underestimation of high wind speeds. The impact of assimilating SWH in the ECMWF Integrated Forecast System was assessed using several numerical experiments. The results show positive impact. Operational assimilation of SWH at ECMWF model is part of the forthcoming model change.  相似文献   
142.
????T/P(TOPEX/POSEIDON)????????????????????????????????????T/P?????????????????????????????????????????????????????????У??????С????????????????????????????????????????????????????Ч??????T/P?????Ч???????0.3m??????T/P????????Jason??1?????????????????????????????????????????????????????????????????????????????????????????????????????á?T/P??Jason??1????????????????Ч?????????????????????????0.21 m??0.05 m??  相似文献   
143.
根据2006年8月在粤东后汪湾海滩收集的滩坎、波浪及地下水位资料,分析了在波浪、潮汐、水下地形等多种影响因子作用下的滩坎地形动力过程.结果表明,显著波陡大则滩坎高度大,反之滩坎高度小;涨潮时滩坎向岸移动,落潮时向海移动;滩坎高度与显著波陡、潮位非线性关系为:Zs=0.5283S s^0.0467(gH)^0.0134;水下沙脊-细沟地形是滩坎演变重要影响因素;台风期间滩坎受侵蚀,台风后堆积;卷破波是滩坎形成的直接驱动力.  相似文献   
144.
The responses to tropical cyclones of ocean wave characteristics in deep water of the western Atlantic Ocean have been investigated extensively, but not the regional seas in the western Pacific such as the South China Sea (SCS), due to a lack of observational and modeling studies there. Since monsoon winds prevail in the SCS but not in the western Atlantic Ocean, the SCS is unique for investigating wave characteristics during a typhoon’s passage in conjunction with steady monsoon wind forcing. To do so, the Wavewatch-III (WW3) is used to study the response of the SCS to Typhoon Muifa (2004), which passed over not only deep water but also the shallow shelf of the SCS. The WW3 model is forced by the NASA QuikSCAT winds and tropical cyclone wind profile model during Typhoon Muifa’s passage from 0000UTC 16 on November to 1200UTC on 25 November 2004. The results reveal the unique features of the SCS wave characteristics in response to Muifa, such as non-decaying, monsoon-generated swell throughout the typhoon period and strong topographic effects on the directional wave spectrum.  相似文献   
145.
For validating the results of retrieved mean wave period, four empirical algorithms established previously are introduced. Based on the data of over five years derived from TOPEX satellite altimeter for the entire East China Sea, ocean wave periods were calculated and statistical comparison among them was performed. The retrieved mean wave period obtained with our new distribution parameters showed better agreement with the wave period TB measured by buoy than that calculated by other three algorithms. The difference between the mean values of and that of TB is 0.16 s and the RMSE (root mean square error) of is the lowest value (0.48).  相似文献   
146.
A new model is proposed to estimate the significant wave heights with ERS-1/2 scatterometer data. The results show that the relationship between wave parameters and radar backscattering cross section is similar to that between wind and the radar backscattering cross section. Therefore, the relationship between significant wave height and the radar backscattering cross section is established with a neural network algorithm, which is, if the average wave period is ≤7s, the root mean square of significant wave...  相似文献   
147.
青藏高原出射长波辐射特征分析   总被引:2,自引:0,他引:2  
苏文颖  毛节泰  纪飞 《大气科学》2000,24(3):313-323
对青藏高原地区1月、4月、7月和10月高时空分辨率的出射长波辐射(OLR)时间序列进行了谱分析。将各点的功率谱分为三类:第一类代表日变化(周期≤1 d),另外两类分别为天气过程(2 d≤周期≤10 d)和低频(周期>10 d)变化;将高原分为6个区域,对区域平均的各季节OLR时间序列进行功率谱分析和显著性检验,结果表明:1、4、10月份高原上以日变化为主;而7月份日变化、天气尺度变化和低频变化的贡献相当。显著性分析表明高原上最为显著的周期为1 d周期,2~4 d的天气尺度振荡也较明显。6~8 d和10~13 d处虽有明显的谱峰,但只有少数地区和个别季节其谱值能超过95%的信度检验。  相似文献   
148.
Based on measurements of waves, currents, and tides off Dahej in the Gulf of Khambhat, hydrodynamics are studied. Estimated tidal constituents show that primary lunar semi-diurnal constituent M2 was the strongest constituent, and the amplitude was found to be around 4.5 times stronger than that of the major diurnal constituent K1. Currents were predominantly tide induced with speeds up to 3.3 m/s and were north-northwest during flood tide and south-southeast during ebb tide. Residual cross-shore and along-shore current was found to be varying with the corresponding change in the cross-shore and along-shore wind speed. Influence of tidal current was observed in most of the wave statistical parameters.  相似文献   
149.
The HY-2 satellite was successfully launched on 16 August 2011. The HY-2 significant wave height (SWH) is validated by the data from the South China Sea (SCS) field experiment, National Data Buoy Center (NDBC/ buoys and Jason-1/2 altimeters, and is corrected using a linear regression with in-situ measurements. Com- pared with NDBC SWH, the HY-2 SWH show a RMS of 0.36 m, which is similar to Jason- 1 and Jason-2 SWH with the RMS of 0.35 m and 0.37 m respectively; the RMS of corrected HY-2 SWH is 0.27 m, similar to 0.27 m and 0.23 m of corrected Jason-1 and Jason-2 SWH. Therefore the accuracy of HY-2 SWH products is close to that of Jason-1/2 SWH, and the linear regression function derived can improve the accuracy of HY-2 SWH products.  相似文献   
150.
HY-2A卫星高度计有效波高信息提取业务化算法   总被引:1,自引:0,他引:1  
2011年8月16日我国成功发射了第一颗自主海洋动力环境卫星HY-2A,有效波高是其搭载的雷达高度计可获取的重要海洋动力环境参数之一。本文详细介绍了应用于HY-2A雷达高度计的有效波高信息提取业务化算法,该算法通过迭代最小二乘拟合方法提取有效波高信息。同时,基于HY-2A雷达高度计业务化运行获取的有效波高数据,分别与Jason-2卫星高度计有效波高和NDBC浮标海浪波高数据进行了比对分析。比较结果表明,HY-2A雷达高度计与Jason-2有效波高的标准偏差为-0.26m,RMS为0.58m;HY-2A高度计与NDBC浮标数据间的标准偏差为-0.22m,RMS为0.37m。结果证明了目前应用于HY-2A雷达高度计业务化运行中的有效波高信息提取算法的可行性。  相似文献   
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