摘 要 “台风”是生成于西北太平洋海域、中心风力达到12级以上即速度大于32。7m/s的热带气旋,是一种具破坏力的天气系统,给人类社会带来生命威胁和严重经济损失。气旋中心的精确定位对监测台风的演变情况和台风路径的预报具有重要意义。星载微波散射计凭借拥有全天时、覆盖范围广等优良观测特性,常被用于反演海面风场,是当前快速获取大范围海面风场信息的最理想的一种遥感手段。
本文首先使用海洋二号HY-2卫星观测到的台风实况数据进行统计插值的预处理得到像元的风矢量单元信息,结合区域风矢量风速经过矢量叠加反演并绘制得到风场图。接着研讨台风天气情况下的区域风场构造特点,利用目视判读风向漩涡中心的方法并且寻找高风速局部区域极小值点来确定台风中心的人工定位原则,用此原则对多期影像进行台风中心识别,获取台风移动路径。最后,进行对监测的台风路径数据精度评价策略的研究,采用实测最佳路径点和中央气象台发布的同一时刻的台风中心位置的最大圆距离d及其相关结果作为精度评估指标,并对编号为1622的台风“海马”的监测数据进行实例精度评估,与中央气象台发布的最佳台风实况路径数据对比检验。89851
结果阐明,基于微波散射计所制定的台风中心人工定位方法能够较为有效地实时对台风监测,利用台风“海马”的连续观测数据分析得到的台风路径结果和发布的最佳路径数据较为一致。针对研究的结果分析,在文章末尾展望了几个方面的改进方向。
毕业论文关键字: 微波散射计 风场反演 中心定位 台风路径 精度评估
Abstract
"Typhoon" is a tropical cyclone with the central wind of force 12 (the wind speed greater than 32。7 m / s) or more emerged in the Northwest Pacific Ocean。 Typhoon is a destructive weather system that brings life safety threats and serious economic losses to human society。 The precise positioning of the cyclone center has great significance to monitor the evolution of the typhoon and the prediction of the typhoon path。 The spaceborne microwave scatterometer posseses excellent observing characteristics with full-day and large-scale coverage that is often used as an ideal remote sensing method for quickly obtaining large-scale sea surface wind information。
In this paper, we first use the typhoon data of the HY-2 to calculate the wind vector unit information of the pixel, and then combine the regional wind vector wind speed through the vector inversion and draw the wind field。 Then, the wind field structure of typhoon weather is studied, and the principle of manual positioning of typhoon center is determined by visually judging the direction of wind vortex center and finding the local point of high wind speed。 Identify, get the typhoon movement path。 Finally, the maximum distance between the measured path point and the corresponding typhoon monitoring point data and its correlation result are used as the accuracy evaluation index, then evaluate the accuracy of the monitoring data of Typhoon No。 1622 "Hippocampus" as one examples, and compare with the best typhoon path data released from Central Meteorological Observatory。
The results show that the typhoon center localization method based on the microwave scatterometer can be used to carry out the real-time monitoring of the typhoon, and the typhoon path results obtained by the continuous observation data of the typhoon "hippocampus" are similar to the best route offered by authority,but the wind strength development results in large errors。In view of the results of the study, at the end of the article, we look forward to several aspects of improvement。