Three-dimensional Visualization Technique And Characters Pick-up For Severe Convective Cloud

The pulse-Doppler radar is widely used in weather investigation, is the main instrument that can detect precipitation system and monitor Severe Convective Weather (including hailstorm, gale, cyclone, violent flood and so on).In order to exhibit information contained in radar initial data files from various angles of view by means of bitmaps, this dissertation study the following aspects. The productions will be used to assist meteorologic analysis.1. Build and display the reflectivity images and velocity images of Doppler radar.One merit of Chinese new generation of weather radar is that the initial data is digital, so the initial data can be processed by appropriate algorithms to create a series of productions. According to the framework of radar data file, this system read reflectivity data and velocity data information from it. Then designed algorithms to build a reflectivity image or a velocity image. The system built eighteen radia bitmaps in less than three seconds, and the image quality is satisfying.2. Realize three-dimensional section plane of discretionary transversal using radar data in multiple elevationsIn order to visualize the three-dimensional conformation of cloud and echo distributing status, this system synthesized every elevation's data information to realize cloud three-dimensional section plane. Compared with conventional weather section, this section is in a three-dimensional reference frame, so it has spacial position information. Also, in this system, the transversal's angle and longness can be discretionary.3. The cloud conformation's visualization technique based on three-dimensional section planeWhen the transversal moves along a radius, both spacial position and content of the section change. This evolvement course is represented through a sequence of section planes. Though the transversal can be discretionary choose an appropriate transversal according to aerography knowledge and experience can get a better observational effect. Further more the system selects an appropriate observing angle according to optic factors to exhibit the cloud conformation as clear as possible.4. Analyze and pick up cloud three-dimensional conformation charactersThere're a lot of characters in cloud three-dimensional conformation to be studied, induced and picked up automatically. Define appropriate characters and pick up them in time can help to describe cloud three-dimensional conformation quantificationally to analyze and understand the weather status and to improve the veracity of severe convective weather forecast. Primary attempt has been made in this dissertation, some characters about cloud three-dimensional conformation have been defined and picked up. They are energy, thickness, height and their changes.All the software developments are realized in the Visual C++6.0 platform. In this dissertation, report algorithms'effect by means of bitmaps, and the processing results are satisfying.