Research And Implementation Of The Tropical Cyclone Analysis System In The Northwest Pacific

Tropical cyclone(TC)is a destructive tropical weather system,which is divided into six classes according to the classification standard of China Meteorological Administration,including tropical depression,tropical storm,strong tropical storm,typhoon,strong typhoon and super typhoon.The northwest Pacific Ocean is the world's most frequent area for tropical cyclones,and is the only sea area in the world where tropical cyclone activity can be observed throughout the year.The coastal region of China is located on the west coast of the Pacific Ocean,so it has become one of the countries in the world that suffer from typhoon disasters more seriously.In order to grasp the activity pattern of tropical cyclones and effectively reduce the disaster losses caused by tropical cyclones,scholars at home and abroad have done a lot of research on the spatial and temporal characteristics of tropical cyclones in the northwest Pacific Ocean.In recent years,more and more scholars have built a tropical cyclone analysis system based on Web GIS technology to manage,share,analyze and forecast tropical cyclone data,which is of great significance for tropical cyclone disaster prevention and mitigation.In this paper,we developed the "Northwest Pacific Tropical Cyclone Analysis System" based on Node.js,Vue.js and Web GIS technologies.The system has the functions of multi-conditional query and statistical analysis of tropical cyclone data,which can help researchers to query and obtain the data of tropical cyclones in the Northwest Pacific Ocean,and to study the spatial and temporal characteristics of tropical cyclones in the Northwest Pacific Ocean.The main research works and results are as follows.(1)Design of the tropical cyclone analysis system in the northwest Pacific OceanThrough the research on the construction of the tropical cyclone analysis system and the summary and analysis of the current situation of the tropical cyclone path clustering method,the requirements for the construction of the system were clarified,and the Northwest Pacific tropical cyclone analysis system with the functions of tropical cyclone query,tropical cyclone visualization,statistical analysis of tropical cyclone characteristic quantities(frequency,intensity,period,direction of travel,energy dissipation index),source analysis and path analysis was designed.(2)Research on the path clustering algorithm of tropical cyclones in the Northwest Pacific OceanThe tropical cyclone path clustering method based on K-Means algorithm is studied to determine the best clustering number K of tropical cyclone paths in the northwest Pacific Ocean by using elbow method and regression analysis,and the results show that the tropical cyclone path data in the northwest Pacific Ocean from 1966-2019 are divided into 5 classes best and the tropical cyclone paths in the northwest Pacific eye are divided when K is equal to 5.Then the influence of the weight coefficient(w(i))in the formula of tropical cyclone description parameter on the clustering effect is discussed,and the clustering effect of each class is better when w(i)is taken as 1.After that,the results of the classification were compared and analyzed with the previous results using the empirical discriminant method,and it was concluded that both of them were the same in the westward type toward the division.A part of the northwest landing type in the empirical discriminant classification is included in the westward direction result of clustering using K-Means algorithm.As for the turning paths in the empirical discrimination method classification,they are classified into three categories: far sea parabolic,near sea parabolic and long hook type when clustering with K-means algorithm.Finally,the case verifies that the K-Means algorithm can accurately classify the tropical cyclone paths.(3)Implementation of a tropical cyclone analysis system for the Northwest Pacific Ocean.The Northwest Pacific Tropical Cyclone Analysis System with tropical cyclone query function,statistical analysis function,tropical cyclone data visualization function and tropical cyclone path clustering function based on K-Means algorithm has been developed and implemented.