EVALUATION OF THE PARAMETERIZATION SCHEMES AND NUDGING TECHNIQUES IN GRAPES FOR WARM SECTOR TORRENTIAL RAINS USING SURFACE OBSERVATIONS     

钟水新  杨帅  陈子通 《热带气象学报(英文版)》2019,25(3):353-364

Sensitivities of parameterization schemes were conducted based on the Global/Regional Assimilation and Prediction System (GRAPES) model. Surface observations were used to evaluate the simulations and to improve the model’s ability to simulate the extreme precipitation over southern China on 20 July 2016. The results showed that GRAPES captured the large-scale precipitation over southern China but failed to predict the extreme precipitation over Xinyi. The model showed a systematic cold biases by adopting different parameterization schemes. In particular, the ECMWF analyses data showed a strong cold bias over Guangdong province and Guangxi Region. Observational nudging results showed that the surface temperature could largely help to alleviate the cold bias. The alleviation in the warm sector accounted for main improvement by the nudging scheme, and the RMSE was reduced by 1.56 degree from 3.25 degree to 1.69 degree by 1-h simulation and with 1.3 degree alleviation by 2-h simulation. Sensitivities using different parameterizations and the nudging scheme showed that the model’s underestimation of the precipitation was still present despite improvements in the predictions of surface temperature.  相似文献   

A STUDY ON THE APPLICATION OF FY-2E CLOUD DRIFT WIND HEIGHT REASSIGNMENT IN NUMERICAL FORECAST OF TYPHOON CHANTHU (1003) TRACK     

李昊睿  丁伟钰  薛纪善  陈子通  高郁东 《热带气象学报(英文版)》2015,21(1):34-42

In this paper, we first analyzed cloud drift wind(CDW) data distribution in the vertical direction, and then reassigned the height of every CDW in the research domain in terms of background information, and finally, conducted contrast numerical experiments of assimilating the CDW data before and after reassignment to examine the impacts on the forecast of the track of Typhoon Chanthu(1003) from 00:00(Coordinated Universal Time) 21 July to 00:00 UTC23 July, 2010. The analysis results of the CDW data indicate that the number of CDWs is mainly distributed in the midand upper-troposphere above 500 h Pa, with the maximum number at about 300 h Pa. The height reassigning method mentioned in this work may update the height effectively, and the CDW data are distributed reasonably and no obvious contradiction occurs in the horizontal direction after height reassignment. After assimilating the height-reassigned CDW data, especially the water vapor CDW data, the initial wind field around Typhoon Chanthu(1003) became more reasonable, and then the steering current leading the typhoon to move to the correct location became stronger. As a result, the numerical track predictions are improved.  相似文献   

粤西水东弧形海岸海滩剖面的地貌状态   总被引：7，自引：0，他引：7  

陈子Shen  李春初 《热带海洋》1993,12(2):61-68

  相似文献   

粤西水东湾现代沉积环境特征与泥沙搬运路径   总被引：3，自引：0，他引：3  

陈子Shen 《热带海洋》1996,15(3):6-13

对粤西水东湾沉积地貌单元的现代沉积物分布特征分析与泥沙净搬运矢量计算表明，滨面斜坡沉积物主要由砂粒吸物质组成，粒级参数Ｍｄ，ＱＤ和ＳＫ具有从海向岸，自东向西变化的总趋势，泥沙净搬运趋势以向岸和西北为主，落潮三角洲沉积物较基邻近滨面斜坡有所粗化，分选从中部向西侧变泥沙在落潮流与波浪驱动下沿落潮三角洲边缘向西运动，口门内潮汐通道深槽泥沙净驼趋势指向湖，湖区的沉积物为泥质为主，分选中等至差，并形成绕涨潮  相似文献   

海温场的递归滤波分析   总被引：1，自引：0，他引：1  

王同美  梁必骐  陈子通 《海洋学报》2000,22(1):35-42

递归滤波(RF)是一种属于经验线性插值类的客观分析方法。因其处理边界域和背景场的独特能力以及在计算机处理上的快速便捷优于其他的传统分析方法,适合于分析诸多资料量大(如卫星资料)、不同来源的不均匀资料。本文主要发展这一客观分析方法在海温场分析上的应用。综合利用各种时空分布和精确度均不相同的海温资料,对几个基本参数的取法进行调试并选取适当的值,分析得出细网格的海温场。结果表明,递归滤波方法不仅灵活简便,而且分析出的海温场质量好,基本上可以反映海温的实际情形。对海温场的分析还可为其他从卫星等提取的非常规资料分析提供借鉴。  相似文献   

Forecast Performance of the Pre-operational CMA-TRAMS (EPS) in South China During April - September 2020     

时洋  张旭斌  戴光丰  杨兆礼  涂静  陈子通 《热带气象学报(英文版)》2023,29(2):236-251

The mesoscale ensemble prediction system based on the Tropical Regional Atmosphere Model for the South China Sea (CMA-TRAMS (EPS)) has been pre-operational since April 2020 at South China Regional Meteorological Center (SCRMC), which was developed by the Guangzhou Institute of Tropical and Marine Meteorology (GITMM). To better understand the performance of the CMA-TRAMS (EPS) and provide guidance to forecasters, we assess the performance of this system on both deterministic and probabilistic forecasts from April to September 2020 in this study through objective verification. Compared with the control (deterministic) forecasts, the ensemble mean of the CMATRAMS (EPS) shows advantages in most non-precipitation variables. In addition, the threat score indicates that the CMA-TRAMS (EPS) obviously improves light and heavy rainfall forecasts in terms of the probability-matched mean. Compared with the European Center for Medium-range Weather Forecasts operational ensemble prediction system (ECMWF-EPS), the CMA-TRAMS (EPS) improves the probabilistic forecasts of light rainfall in terms of accuracy, reliability and discrimination, and this system also improves the heavy rainfall forecasts in terms of discrimination. Moreover, two typical heavy rainfall cases in south China during the pre-summer rainy season are investigated to visually demonstrate the deterministic and probabilistic forecasts, and the results of these two cases indicate the differences and advantages (deficiencies) of the two ensemble systems.  相似文献   

APPLICATION EXPERIMENT OF ASSIMILATING RADAR-RETRIEVED WATER VAPOR IN SHORT-RANGE FORECAST OF RAINFALL IN THE ANNUALLY FIRST RAINY SEASON OVER SOUTH CHINA     

张诚忠  陈子通  万齐林  林振敏  黄燕燕  戴光丰  丁伟钰 《热带气象学报(英文版)》2016,22(4):578-588

A scheme of assimilating radar-retrieved water vapor is adopted to improve the quality of NWP initial field for improvement of the accuracy of short-range precipitation prediction. To reveal the impact of the assimilation of radar-retrieved water vapor on short-term precipitation forecast, three parallel experiments, cold start, hot start and hot start plus the assimilation of radar-retrieved water vapor, are designed to simulate the 31 days of May, 2013 with a fine numerical model for South China. Furthermore, a case of heavy rain that occurred from 8—9 May 2013 over the region from the southwest of Guangdong province to Pearl River Delta is analyzed in detail. Results show that the cold start experiment is not conducive to precipitation 12 hours ahead; the hot start experiment is able to reproduce well the first 6 hours of precipitation, but badly for subsequent prediction; the experiment of assimilating radar-retrieved water vapor is not only able to simulate well the precipitation 6 hours ahead, but also able to correctly predict the evolution of rain bands from 6 to 12 hours in advance.  相似文献   

不同水汽分析场对一次华南前汛期暴雨预报的影响分析   总被引：2，自引：0，他引：2  

徐道生  张艳霞  陈子通  戴光丰  钟水新 《热带气象学报》2016,(2):155-162

利用华南高分辨率模式分析了不同水汽分析场对一次华南前汛期暴雨模式预报效果的影响。分别使用来自NCEP-GFS（Global forecast system）和ECMWF-IFS（Integrated forecast system）两个不同预报系统提供的分析场进行模拟发现,使用IFS模式提供的初始场进行预报能够得到更为合理的降水预报效果,并发现初值中850hPa高度以下的水汽对本次过程的降水预报结果具有显著影响。由于在华南地区两种初始场内低层的水汽分布存在较大差异,导致了模式预报过程中出现了不同的降水发生机制,最终导致降水预报出现明显的偏差。在GFS分析场的基础上,进一步利用GRAPES-3DVar系统对常规观测资料进行再次同化,发现同化对本次降水过程的前期预报有改进,但是对24 h累计降水的预报改进并不明显。  相似文献   

相对海平面升降与中国南方二叠纪生物礁油气藏   总被引：7，自引：0，他引：7  

沈安江  陈子 《沉积学报》1999,17(3)

根据相对海平面升降速率与礁生长速率之间的关系,中国南方二叠纪生物礁可划分为三种类型∶退积礁、并进礁和进积礁。不同类型的礁有其特有的成岩、成藏模式。首先,相对海平面升降控制了礁储集体的非均质性,这种非均质性又控制着原油在礁体内的时空展布,搞清这种时空展布规律对礁油气藏勘探极为重要;其次,相对海平面升降控制着礁含油气系统要素的形成机理及空间配置关系,对礁的含油气系统进行分析可在钻前对礁的含油气潜力作出初步评价。不同类型的礁体群均具有各自不同的成因联系及时空迁移规律,分析这种成因联系及时空迁移规律使我们可以更加准确预测潜伏礁体。  相似文献   

川东-鄂西地区二叠纪生物礁成因类型及潜伏礁预测   总被引：1，自引：0，他引：1  

陈子炓  沈安江 《地质通报》2000,19(3)

从相对海平面升降对礁生长发育控制的角度建立新的生物礁成因分类 (进积礁、并进礁和退积礁 ) ,据此描述川东—鄂西地区二叠纪生物礁的属性 ,认为该区进积礁和退积礁并存。根据礁体的进积和退积方向对潜伏礁进行预测 ,指出鄂西地区见天坝礁群的东南侧应该存在层位相当于长兴组三段的潜伏礁带 ,华蓥山—川东成礁带以西可能存在层位相当于长兴组三段顶的潜伏礁带。  相似文献