Application of Gray Theory on Typhoon- Rainfall Estimation in Chiayi City

• Main Authors: Fu-Tsan Hsu, 徐福燦
• Other Authors: Chyan-Deng Jan
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/05185096956256836295

碩士 === 國立成功大學 === 水利及海洋工程學系碩博士班 === 93 === 　Storms cause casualties of human beings and properties. It is important to estimate rainfall via analyzing characteristics of typhoons. There are highly uncertainties of the formation of a typhoon, the tracks, as well as its rainfall. This study has built up a Typhoon Estimation model by using the Gray System and historical data measured by Chiayi Weather Station, as the Gray Theory can deal with it. The applicability of the model has been tested by comparing the results with the practical records. This study built up the Typhoon Estimation model via the Gray Theory of GM (1, N) which uses four factors as inputs: the maximum humidity, the maximum temperature, the maximum pressure, and the maximum wind velocity as well during the typhoon period. 　There were 38 typhoon records of rainfall higher than 50 mm between 1969 and 2002. The 38 typhoon records were separated into two sets in the present study: the first sets of 20 rainfall records randomly selected from available records between 1969 and 1992 were used to build the model. The second sets of 18 rainfall records between 1993 and 2002 were used for model’s evaluation. The result of model’s evaluation shows that the errors between the measured and the forecasted rainfall caused by typhoons are all less than 17% of all patterns of typhoon.