Application of GIS to Tropical Cyclone Product Generation System

China is one of the most typhoon influenced countries in the world, so it is urgent to strengthen the capacity of typhoon forecast services, in which Geographic Information System (GIS) plays a more important role increasingly. On analyzing the operational requirement of typhoon forecast, the workflow of tropical cyclone product generation is designed with the support of historical and real time typhoon spatial database. First, visualize typhoon track and wind data. Second, smooth typhoon track, edit feature property and validate topology for spatial analysis. Then analyze the data to obtain landing area, real time and future affected area, and similar track search results. Finally, service product is generated using Microsoft Office development technology. Four key issues of GIS application on production system are discussed in details. GIS spatial analysis aims at extracting and transporting spatial information based on geospatial object location and geometry character. Using Geodatabaseand Spatial Data Engine, historical and real time typhoon database can be built and provide the ability of data record and update. ESRI representation symbolizes data using a flexible and rule based structure that is stored inside the geodatabase along with data, supporting multiple representations simultaneously. Constructing feature filling modes and color representation styles by standard rules can efficiently implement the visualization of large volume of typhoon data. In order to precaution which administrative region would be affected in the near future, the spatial overlay analysis is carried out to extract and transport spatial information. Two probability ellipse methods of typhoon track forecasting are also proposed to predict potentially infected districts ahead of schedule. With spatial interpolation method intensive typhoon forecasts are made for multiple points, and for each point a weight error radius is calculated, then the vertical line throughout the points are determined, finally the control points are linked to construct a polygon and smoothed with Bezier Curve. Dynamic buffer method is based on integral splits the typhoon tracks by kilometer unit, by the ratio of the length of typhoon track the buffer radius can be calculated, after then do dynamic buffer based on a series of radiuses and combine the buffer area to a probability ellipse. GIS provides a reliable scientific basis for typhoon forecast, and with its aid more applicable and efficient typhoon forecast models can be achieved in the near future.