探空资料云检测及其统计研究

基于已知的云垂直结构判断的方法,将相对湿度阈值法与温度露点法相结合,并加以改进,得到更加科学有效的云垂直结构判断方法。利用南京地区探空站的探空资料数据,分析得到了该地区的云垂直结构参数,并对全年云垂直结构特征进行了统计分析。经过统计分析发现:这种改进的相对湿度阈值法是科学有效的;南京地区夏秋季节有云的概率大,多层云的状况较多;春冬季节有云的概率相对较小,单层云的状况较多;云层厚度呈现出"夏厚冬薄"、中低云厚而高云薄的规律。     

NMC与HLAFS降水预报的比较

建立了一套既适用于对预报员降水预报评估,又适用于对数值预报模式降水预报评估的客观检验方法,从对１９９６年７－９月检验的结果分析表明预报员对大雨预报Ｔｓ评分高于ＨＬＡＦＳ并且除西北地区外,其它区的２４小时大雨预报都超过气候概率,表现为大于０的技巧评分,预报员和ＨＬＡＦＳ对大雨预报的漏报率多于空报率,而对小雨和中雨的预报相反,两者都是空报多于漏报,预报中对西北地区的降水预报漏报较多。     

干湿表法测湿的实时性处理

用单片微机，采用洛氏（Ｌｏｗｅ）多项式和高级编译程序，对干湿表法测湿进行了实时性和智能化处理。使干湿法测湿具有了更广泛的实用价值．     

Dynamics and control of towed underwater vehicle system, part II: model validation and turn maneuver optimization

This paper presents a validation of a three-dimensional dynamics model of a towed underwater vehicle system and discusses an application of the model to improve the performance of the system during a turn maneuver. The model was validated by comparing its results to experimental sea trial data, as well as to results from another independently developed simulation. The dynamics model was then imbedded in an optimization routine. This routine was used to vary turn radii in order to improve the U-turn performance. Significant improvements were obtained relative to a standard semicircular turn geometry.     

Comparison of Sea Surface Heights Derived from Satellite Altimetry and from Ocean Bottom Pressure Gauges: The SW Pacific MOTEVAS Project

A bottom pressure gauge (BPG) was installed in proximity (3.7 km at closest approach) of Jason-1 and formerly TOPEX/Poseidon (T/P) ground track No. 238 at the Wusi site, located ∼ 10 km offshore off the west coast of Santo Island, Vanuatu, Southwest (SW) Pacific. Sea level variations are inferred from the bottom pressure, seawater temperature, and salinity, corrected for the measured surface atmospheric pressure. The expansion of the water column (steric increase in sea surface height, SSH) due to temperature and salinity changes is approximated by the equation of state. We compare time series of SSH derived from T/P Side B altimeter Geophysical Data Records (GDR) and Jason-1 Interim Geophysical Data Records (IGDR), with the gauge-inferred sea level variations. Since altimeter SSH is a geocentric measurement, whereas the gauge-inferred observation is a relative sea level measurement, SSH comparison is conducted with the means of both series removed in this study. In addition, high-rate (1-Hz) bottom pressure implied wave heights (H_1/3) are compared with the significant wave height (SWH) measured by Jason-1. Noticeable discrepancy is found in this comparison for high waves, however the differences do not contribute significantly to the difference in sea level variations observed between the altimeter and the pressure gauge. In situ atmospheric pressure measurements are also used to verify the inverse barometer (IB) and the dry troposphere corrections (DTC) used in the Jason IGDR. We observe a bias between the IGDR corrections and those derived from the local sensors. Standard deviations of the sea level differences between T/P and BPG is 52 mm and is 48 mm between Jason and BPG, indicating that both altimeters have similar performance at the Wusi site and that it is feasible to conduct long-term monitoring of altimetry at such a site.     

光纤化学/生物传感技术在海洋环境监测中的应用

本文通过光纤溶解氧、 p H、湿度等化学传感探头及发光菌水质毒性监测生物传感探头的研制 ,开发出了一类能用于环境监测的新型传感器。本文的创新之处在于传感探头的设计与包装 ,以及数种可逆性、选择性、稳定性、使用寿命、响应时间、灵敏度等响应特性具佳的化学及生物传感膜的配方和制作技术。利用这些技术 ,通过对光纤探头的设计与包装 ,可以实现在现场及实验室模拟条件下对样品的选择性检测。研制的传感器能广泛应用于海洋污染调查、内河水质评价、水产养殖、工矿企业水气排污自检等诸多方面。     

ECMWF高分辨率数值模式对广安地区暴雨预报性能检验分析

为了解ECMWF高分辨率数值预报模式(以下简称"ECMWF")对广安地区暴雨的预报性能,提高预报质量。利用ECMWF模式资料、广安地区4个国家观测站和160个区域自动站的逐日降水资料,对2015—2017年广安地区出现的34次中雨及以上量级降水(其中14次暴雨)天气过程进行分析。结果表明:直接以ECMWF暴雨预报结果进行暴雨预报,易出现漏报,评分质量较低。当ECMWF预报满足:中、短期均预报降水R≥50 mm;中期预报R≥25 mm、短期预报R≥50 mm;中期预报R≥50 mm、短期预报R≥25 mm;中、短期均预报R≥35 mm 4个订正条件之一时,进行订正预报暴雨,评分高,空、漏报率低,命中率高,可有效提高暴雨预报质量。同时,ECMWF在暴雨的持续时间、强降水时段、落区和面雨量预报中均有良好的预报指导意义。     

Validation and Spatiotemporal Distribution of GEOS-5-Based Planetary Boundary Layer Height and Relative Humidity in China

Few studies have specifically focused on the validation and spatiotemporal distribution of planetary boundary layer height(PBLH) and relative humidity(RH) data in China. In this analysis, continuous PBLH and surface-level RH data simulated from GEOS-5 between 2004 and 2012, were validated against ground-based observations. Overall, the simulated RH was consistent with the statistical data from meteorological stations, with a correlation coefficient of 0.78 and a slope of 0.9. However, the simulated PBLH was underestimated compared to LIDAR data by a factor of approximately two,which was primarily because of poor simulation in late summer and early autumn. We further examined the spatiotemporal distribution characteristics of two factors in four regions—North China, South China, Northwest China, and the Tibetan Plateau. The results showed that the annual PBLH trends in all regions were fairly moderate but sensitive to solar radiation and precipitation, which explains why the PBLH values were ranked in order from largest to smallest as follows: Tibetan Plateau, Northwest China, North China, and South China. Strong seasonal variation of the PBLH exhibited high values in summer and low values in winter, which was also consistent with the turbulent vertical exchange. Not surprisingly, the highest RH in South China and the lowest RH in desert areas of Northwest China(less than 30%). Seasonally, South China exhibited little variation, whereas Northwest China exhibited its highest humidity in winter and lowest humidity in spring,the maximum values in the other regions were obtained from July to September.     

浙江平原时序InSAR地面沉降监测

针对浙江省地面沉降监测需求,研究利用时序InSAR技术进行浙江省平原区地面沉降监测的技术流程。以上虞区块为例,反演得到上虞地区2013-2014年度地面沉降信息;结合同期外业水准测量数据,在传统点-点、点-面验证基础上,提出点-线验证方式,将几种分析评价方法进行了对比,对InSAR地面沉降监测精度进行评价分析;最后结合外业实地调查的情况,证明了InSAR技术监测大范围地面沉降分布状况和发现区域沉降中心的有效性和精确性。     

暴雨期间GNSS遥感气象要素的时序变化

针对暴雨短临预报准确率不高的问题,该文结合香港地区的暴雨实例,分析暴雨发生期间天气尺度特征和GNSS气象要素的时序变化特点及其各要素之间的相关性。研究结果表明:强烈的西南气流带来丰富水汽,高空强烈的辐散抽吸引起低层气压降低和对流运动的发展,配合中层低槽过境和低层冷空气南下,为暴雨发生提供条件;天顶对流层延迟变化的主要贡献来自大气水汽含量,可以用天顶对流层延迟替代大气水汽含量分析大气中的水汽累计及变化情况;暴雨发生前,气温较高,大气水汽含量和相对湿度时序增长快速,增长强度及其维持高水平状态的时长与后续雨量有较好的对应关系;大气水汽含量和相对湿度时序的上升分别反映了降水之前的充足水汽供应和水汽正在转向于饱和状态。