联合地基GPS及空基COSMIC的对流层水汽三维层析

发布时间：2018-06-22 09:38

本文选题：层析 + 水汽　；参考：《中南大学》2013年硕士论文

【摘要】：准确的获取大气中水汽的三维分布信息,能够有效地改善气候监测及气象预测的精度。此外,还能够有效地改善数值天气预报的初始湿度场,有效地提高数值天气预报的精度。GPS技术为探测水汽的三维分布提供了一种新的方法,它具有全天候作业、不受天气情况影响、探测精度高、实时连续性作业等优点,有效地弥补了传统探测方法的不足。本论文联合地基GPS及空基COSMIC(The Constellation Observing System for Meteorology, Ionosphere and Climate)掩星产品对香港地区的水汽三维分布进行了研究。针对传统迭代重构算法的局限性,提出了一种改进的水汽层析的迭代重构算法；为了弥补单一重构算法的缺点,又提出了一种组合重构算法反演水汽的三维分布。通过对香港地区12个气象监测站提供的GPS观测数据进行试算,验证了新方法的可行性及其优越性。本论文的主要研究工作和成果如下： 1)利用精密单点定位的方法算取天顶路径延迟(ZPD),通过Saastamoinen模型(ZHD)求取天顶干延迟后求取天顶湿延迟(ZWD),并最终获取斜路径水汽含量(SWV)。 2)针对经典代数重构算法在大尺度水汽反演中迭代收敛速度慢、重构精度较低的缺点,本文提出了一种改进的代数重构算法。该算法能够自动地调节算法中的松弛参数向量中的各个元素,逐步改善反演的精度,并提高反演的速度。 3)针对单个重构算法在对流层层析水汽密度值反演中的局限性,提出了一种组合重构水汽层析方法。在获取水汽垂直分布的时,组合重构方法的精度优于单一的重构算法的精度。此外,组合重构算法有效地解决了初始值选取的问题。 4)通过求取2012年7月20日到8月2日水汽的三维分布,并将其转化为水汽的柱积分水汽总量,根据该值的分布及变化研究了2012年7月22日到28日暴雨天气的过程。图30幅,表7个,参考文献86个。
[Abstract]:The accurate acquisition of three-dimensional distribution information of water vapor in the atmosphere can effectively improve the accuracy of climate monitoring and meteorological prediction. In addition, it can effectively improve the initial humidity field of the numerical weather forecast, and effectively improve the precision of the numerical weather forecast.GPS technology to provide a new method for detecting the three-dimensional distribution of water vapor. All weather operations, which are not affected by weather conditions, have high detection accuracy and real-time continuous operation, have effectively compensated for the shortcomings of traditional detection methods.
This paper combines ground GPS and space-based COSMIC (The Constellation Observing System for Meteorology, Ionosphere and Climate) to study the three-dimensional distribution of water vapor in Hongkong area. In view of the limitations of the traditional iterative reconstruction algorithm, an improved iterative reconstruction algorithm for water vapor chromatography is proposed. To reconstruct the algorithm, a combination reconstruction algorithm is proposed to retrieve the three-dimensional distribution of water vapor. The feasibility and superiority of the new method are verified by a trial calculation of the GPS observation data provided by 12 meteorological monitoring stations in Hongkong area. The main research work and results of this paper are as follows:
1) the zenith path delay (ZPD) is calculated by the precise single point positioning method, and the zenith wet delay (ZWD) is obtained after the zenith dry delay (ZWD) through the ZHD (ZHD), and the water vapor content of the oblique path (SWV) is finally obtained.
2) in view of the shortcoming of slow convergence rate and low reconstruction precision of the classical algebraic reconstruction algorithm in large scale water vapor inversion, an improved algebraic reconstruction algorithm is proposed in this paper. This algorithm can automatically adjust the elements of the relaxation parameter vector in the algorithm, gradually improve the accuracy of the inversion and improve the speed of the inversion.
3) in view of the limitation of the single reconstruction algorithm in the inversion of the tropospheric chromatographic vapor density, a combined reconstruction water vapor tomography method is proposed. When obtaining the vertical distribution of the water vapor, the precision of the combined reconstruction method is better than the single reconstruction algorithm. In addition, the combined reconstruction algorithm can effectively solve the problem of the initial value selection.
4) by obtaining the three-dimensional distribution of water vapor from July 20, 2012 to August 2nd and converting it into the total amount of water vapor in the column of water vapor, the process of rainstorm from July 22, 2012 to 28 is studied according to the distribution and change of the value. 30 maps, 7 tables and 86 references are made.
【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P228.4;P426;P412

【参考文献】