Application of Rainfall Frequency Analysis on Studying Rainfall Distribution Characteristics of Chia-Nan Plain Area in Southern Taiwan

嘉南地區降雨分佈特性之探討

李錦育(Chin-Yu Lee)

《作物、環境與生物資訊》 2卷1期 (2005/03) Pp. 31-38

https://doi.org/10.30061/CEB.200503.0003

摘要

本研究針對嘉南地區雨量分佈特性，利用常態分佈、對數常態分佈、極端值第一型分佈、皮爾遜第三型分佈及對數皮爾遜第三型分佈進行分析，並選用178個具10年以上資料之測站，以年降雨量資料進行頻率分析。結果發現：以對數皮爾遜第三型分佈為主要之機率分佈，佔總測站數量之50%。本研究並利用主成分分析法，求得降雨空間分佈之兩個主要成分。結果顯示：前兩個主成分之特徵值，具有解釋年降雨總變方程度73%之能力，其中第一主成分佔55.7%，第二主成份佔17.5%，可據以其代替原始的多項變量，以達到成分因子獨立及資料精簡等效用。

關鍵字

頻率分析 ； 主成分分析

並列摘要

This study aims at studying the rainfall distribution characteristics of Chia-Nan plain area, by using different statistical analyses such as normal distribution, log-normal distribution, extreme value type I distribution, Pearson type Ⅲdistribution, and log-Pearson type Ⅲ distribution. 178 stations having annual rainfall data over ten years were selected to perform frequency analysis. Results showed that the log-Pearson type Ⅲ distribution performed the best in probability distribution, occupying 50% of the total station number. This study also applied principal component analysis to derive two principal components of the rainfall spatial distribution. Results indicated that the eigenvalues of the two principal components were capable of explaining 73% of the total variance of annual rainfall, with first principal component occupied 55.7% and the second principal component occupied 17.5%. These two components can be used to replace most of the original variables in satisfying the requirement of component independence and data reduction.

並列關鍵字

Frequency analysis ； Principal Component ； Analysis