The Design And Realization Of Software For Aerosol Optical Depth Retrieval

With Information Technology moving forward, Computer Science is introduced into the field of Atmospheric Sciences. One of current hot issues in Atmospheric and Environmental Science is to retrieve aerosol optical depth (AOD). In recent years, many methods and softwares for the retrieval of AOD have come out. However, these softwares mainly focus on part of the retrieval process, and no one for the whole process is developed.Based on a radiative transfer model, MODIS data is used to estimate surface reflectance, apparent reflectance, aerosol model and composition, then a look-up table of apparent reflectance - surface reflectance - AOD is set up and finally AOD is retrieved. In this paper, a system to retrieve AOD from MODIS data is developed, which visualizes the retrieval process. Instead of part of the process, the whole retrieval process can be carried out by the system.This paper is divided into five chapters. Chapter One is the Preface. In this chapter, the background and significance of the research are introduced. The progress of AOD retrieval at home and abroad is mentioned and then the study objectives and contents of this paper are put forward. Chapter Two presents the theoretical foundations of the AOD retrieval. Firstly, the paper introduces the characters of MODIS data, including its parameters as well as its data structure. And then the process of AOD retrieval is described in detail such as the geometric calibration of MODIS data and so on. Chapter Three is about the general design of the system. The objectives and principles of the system are explained and functions of system module are introduced in this chapter. Chapter Four deals with development of AOD retrieval software, including development environment and realization of the system. Chapter Five summarizes the insufficient and innovative aspects, and brings forward what is going to do for next steps.Several achievements have been reached in the research. Aiming at the whole process of AOD retrieval, a system has been designed to realize the idea of "ONLY One Software Solution". And also with help of Visual C++, a visual user interface is developed for 6S model, which simplifies input of the model and realizes the idea of object-oriented programming. In addition, 6S model is integrated into the system and becomes part of the software, which cuts down the development cycle of the system.