Impacts of TRMM SRR assimilation on the numerical prediction of tropical cyclone   总被引：4，自引：0，他引：4  

MA Leiming  QIN Zenghao  DUAN Yihong  LIANG Xudong  WANG Dongliang 《海洋学报(英文版)》2006,25(5):14-26

1 IntroductionObservation of the tropical rainfall is crucial forthe research on tropical weather and climate. Nu-merous studies have shown that the ingestion of rain-fall data into a numerical model can have considera-ble impacts on simulation results(Kr…  相似文献   

地理信息服务中数据传输性能分析   总被引：2，自引：0，他引：2  

王玉海  张新城  崔铁军  陈应东 《测绘科学》2008,33(6):146-148

地理信息服务系统具有数据密集型和计算密集型的特点,对网络环境的设置有着特殊的需求。本文从地理信息服务系统中对数据传输应用的角度出发,从网络数据传输协议的传输层和应用层两个层次分析地理信息服务系统应用的特殊性,并根据系统应用的特殊需求提出相应的解决方案,提高整个应用系统中各类数据传输的效率、性能和系统运行的稳定性,提高地理信息服务系统为多用户提供地图服务、位置服务以及各种应用服务的综合能力。提高系统适应多用户并发访问海量数据的地图服务作业和频繁访问实效性很强的位置服务作业的能力。  相似文献   

3套资料中西北太平洋热带气旋活动特征的比较分析          下载免费PDF全文

张冬娜  张翰  程旭华  陈大可 《海洋学研究》2020,38(3):48-57

本文使用中国气象局、美国联合台风预警中心和日本气象厅的3套热带气旋最佳路径资料(CMA资料、JTWC资料和RSMC资料)分析了1951—2016年西北太平洋热带气旋活动特征。3套资料反映的结果如下:热带气旋主要发生在10°N—25°N范围内,且1980年前其位置点在纬度上有南移的变化趋势,1980年后则相反;移速主要分布在2~6 m/s区间,在25°N左右移速明显加快,1980年前移速呈显著减小趋势;最大持续风速主要分布在10~15 m/s区间,1980年前最大持续风速有减小趋势;在风速较大的区域热带气旋最大风速半径较小,2001—2016年热带气旋和台风最大风速半径每年分别减小0.46 km和0.54 km。CMA和RSMC资料的结果高度一致,而JTWC资料结果与它们都存在一定的差异。热带气旋位置点频数和强度的变化受资料间差异的影响较大,而其位置及移速的变化则受影响较小。  相似文献   

THE EFFECTS OF BOGUS TYPHOON AND OBSERVED OCEANIC DATA ON THE ABILITY OF T_(213)L_(31) TO PREDICT TC TRACK     

麻素红  王建捷  万丰 《热带气象学报(英文版)》2007,13(2):149-152

The abilities of typhoon (TC) track prediction by a medium-range forecast model T213L31 at National Meteorological Center are analyzed and its ability to improve its TC forecasts is discussed. The results show that about 57% of the TCs could be predicted by T213L31 but the initial position errors are large.The 43% area without the prediction of TC tracks is concentrated between 13°N and 20°N and east of 120°E and lack of conventional observation data is the main reason for the absence of TC prediction in this area.The adding of bogus TC could improve the ability of TC track prediction when there is no TC vortex in the analysis field, but could only have positive effects on the short-range TC track prediction when there is TC vortex in the T213L31 analysis field.  相似文献   

热带气旋进入北部湾后强度增强的环流特征分析     

陈见高安宁  陈润珍何慧钟祥平  赵江洁 《广西气象》2007,28(1):19-24

利用NCEP／NCAR再分析资料，对1949年以来7个进入北部湾后强度突然增强的热带气旋（TC）环流背景特征及物理量场特征进行分析，结果表明，有利TC进入北部湾后强度增强的环流背景是：（1）西太平洋副热带高压稳定加强西伸，（2）热带辐合带北抬至华南沿海活动，（3）西南季风爆发处于活跃期，（4）东风波西移叠加，（5）有适度的弱冷空气侵入；对物理量场的合成分析表明，TC进入北部湾前和进入北部湾后，环流中心附近500hPa涡度变化极小，200hPa高空散度增大，500hPa垂直上升速度增大，850hPa中南半岛水汽输送量增大。  相似文献   

Comparison of Three Tropical Cyclone Intensity Datasets   总被引：3，自引：0，他引：3  

YU Hui  HU Chunmei  JIANG Leyi 《Acta Meteorologica Sinica》2007,21(1):121-128

Analyzed in this paper are the 16-yr (1988-2003) tropical cyclone (TC) intensity data from three major forecast centers of the western North Pacific, i.e., China Meteorological Administration (CMA), Regional Specialized Meteorological Center Tokyo (RSMC Tokyo), and Joint Typhoon Warning Center (JTWC) of the United States. Results show that there are significant discrepancies (at 1% significance level) in the intensity of TCs among the three centers, with a maximum difference for the same TC over 30 m s-1. The flight reconnaissance over TC can minish the discrepancy to some extent. A climatic and persistent prediction model is set up to study the impact of initial data from different forecast centers on the prediction of TC intensity. It is obtained that the root mean square error (RMSE) of a 4-yr independent test is the largest using data from JTWC, while the smallest using data from RSMC Tokyo. Average absolute deviation in 24-h intensity prediction is 2.5 m s-1 between CMA and RSMC Tokyo data, and 4.0 m s-1 between CMA and JTWC data, with a maximum deviation reaching 21 m s-1. Such a problem in the initial value increases the difficulty in intensity prediction of TCs over the western North Pacific.  相似文献   

NUMERICAL STUDY ON THE EFFECTS OF SEA SURFACE TEMPERATURE ON TROPICAL CYCLONE INTENSITY-PART I:NUMERICAL EXPERIMENT OF THE TROPICAL CYCLONE INTENSITY RELATED TO SST Duan Yihong;Qin Zenghao;Gu dianfeng;Li Yongping, Shanghai Typhoon Institute.Shangh     

端义宏  秦曾灏  顾建峰  李永平 《Acta Meteorologica Sinica》1998,(2)

In the context of a model of tropical cyclone intensity based on an improved meso-scaleatmospheric model, numerical simulation is performed of the track and intensity variation oftropical cyclones (TC) arising from sea surface temperature (SST) variation over a specified searegion. Evidence suggests that the model is capable of modeling quite welt the track and intensityof TC: SST variation leads to an abrupt change in the cyclone intensity: the response of thecyclone to the abrupt SST change lasts 8—12 h.  相似文献   

Use of tetracycline hydrochloride and alizarin complexone for immersion marking black rockfish Sebastes schlegelii     

吕红健  张秀梅  付梅  席丹  高天翔 《中国海洋湖沼学报》2014,32(4):810-820

We tested the utility of chemical marking techniques in the juvenile black rockfish Sebastes schlegelii. Juveniles(30–40 mm total length) were immersed in a range of tetracycline hydrochloride(TC) solutions at concentrations ranging from 300 to 500 mg/L, and alizarin complexone(ALC) solutions at concentrations ranging from 200 to 400 mg/L in filtered sea water(salinity of 30) for 24 h, respectively. Otoliths(sagittae, asteriscus), scales, fin rays(dorsal, pectoral, ventral, anal, and caudal fin rays), and fin spines(dorsal, ventral, and anal fin spines) were sampled and used to detect fl uorescent marks after a 60-day growth experiment. With the exception of 300 mg/L TC, acceptable marks were produced in the otoliths and fin spines by all concentrations of TC and ALC. In particular, we observed clearly visible marks in the sagittae, asteriscus, and fin spines under normal light at concentrations of 200–400 mg/L, 250–400 mg/L, and 250–400 mg/L ALC, respectively. Scales and fin rays had acceptable marks at much higher concentrations(≥350 mg/L TC, ≥250 mg/L ALC for scales and ≥350 mg/L TC, ≥300 mg/L ALC for fin rays). The best mark quality(i.e., acceptable marks were observed in all sampled structures after immersion marking) were obtained following immersion in TC at between 350–500 mg/L, and ALC between 300–400 mg/L. In addition, there was no significant difference in survival and growth of TC and ALC marked fish compared to their controls up to 60 days post-marking( P 0.05).  相似文献   

A Statistical Analysis on the E ect of Vertical Wind Shear on Tropical Cyclone Development          下载免费PDF全文

ZHAO Bin  DUAN Yihong  YU Hui  DU Bingyu 《Acta Meteorologica Sinica》2006,20(3):383-388

Using tropical cyclone (TC) best track and intensity of the western North Pacific data from the Joint TyphoonWarning Center (JTWC) of the United States and the NCEP/NCAR reanalysis data for the period of 1992-2002, the effects of vertical wind shear on TC intensity are examined. The samples were limited to the westward or northwestward moving TCs between 5°N and 20°N in order to minimize thermodynamic effects. It is found that the effect of vertical wind shear between 200 and 500 hPa on TC intensity change is larger than that of the shear between 500 and 850 hPa, while similar to that of the shear between 200 and 850 hPa. Vertical wind shear may have a threshold value, which tends to decrease as TC intensifies. As the intensifying rate of TC weakens, the average shear increases. The large shear has the obvious trend of inhibiting TC development. The average shear of TC which can develop into typhoon (tropical depression or tropical storm) is below 7 m s-1 (above 8 m s-1).  相似文献   

Calibration of Infrared Absorption Coefficients for Structural Hydroxyl in Garnet by a Combined Study of Isotope Ratio Spectrometry and Vibrational Spectroscopy     

Lin Zhu  Ren-Xu Chen  Yong-Fei Zheng  Jing Wang  Bing Gong 《Geostandards and Geoanalytical Research》2023,47(1):105-124

An accurate determination of water content in garnet is critical to quantify the transport of water to the deep mantle by the subducted oceanic crust beyond the breakdown of hydrous phases. Fourier transform infrared spectroscopy (FTIR) is the most widely used approach to determine the species and contents of water in garnet. Accurate quantification of OH in garnet requires independent calibration using an external method, as OH absorbance is mineral and composition specific. To obtain the infrared absorption coefficients of structural hydroxyl in garnet, a combined study of spectrometric analyses by FTIR and a method combining a thermal conversion elemental analyser with isotope ratio mass spectrometry (TC/EA-MS) was carried out for fourteen gem-quality natural garnet crystals with variable compositions. The obtained molar absorption coefficients were 9322 ± 338 and 240 ± 26 l mol⁻¹ cm⁻² for grossular- and spessartine-rich garnet and pyrope-almandine garnet, respectively. These results are within the range of previous studies. A new molar absorption coefficient of 689 ± 177 l mol⁻¹ cm⁻² was obtained for pyrope-spessartine garnet. The large variation in the absorption coefficient indicates it is controlled by both garnet composition and OH-absorption bands. The obtained absorption coefficients are only appropriate for certain types of eclogitic garnet, and more studies should be carried out on eclogitic garnets.  相似文献