Rainfall Analysis over Mauritius Using Principal Component Analysis

Abstract

Principal Component Analysis (PCA) is one of the most popular dimensionality-reduction Environmental Management and Sustainable Development ISSN 2164-7682 2014 www.macrothink.org/emsd 95 techniques used for the purpose of classification. It has gained popularity because of its ease of use and optimal nature in a mean square error sense. This paper focuses on an analysis of PCA as a classification tool for rainfall images. Rainfall maps were generated using monthly precipitation data from 226 stations over Mauritius for the years 1992 to 1995 and also for the mean monthly rainfall for the years 1961 to 1990. Three different methods of applying PCA were then used on the rainfall maps and each method generated principal components reflecting the relevant percentage of variability. To interpret these components, a study of the various rainfall bearing climate systems and the wind-field active in Mauritius proved to be necessary to enable their association of the most significant principal components. The effect of altitude on rainfall has been found to have most dominant effect on rainfall. Other climate systems such as the ITCZ, cyclones, anticyclones, cold fronts and the perturbation of easterlies were also found to have specific rainfall patterns associated with them.

Regionalization of precipitation in Mauritius: a statistical approach

“…This is due to the influence of the southeast trade winds (SETWs) on the climate of the island. The resulting effect is a decreasing gradient in precipitation between the southeast and northwest, also observed by Fowdur et al (2014) and Staub et al (2014). This is especially seen on the central plateau which comprises the three inland precipitation regions (regions 2, 3 and 6) determined by the CA.…”

“…The resulting effect is a decreasing gradient in precipitation between the southeast and northwest, also observed by Fowdur et al . () and Staub et al . ().…”

“…Fowdur et al . (), who investigated the precipitation of Mauritius, also observed the effect of windfields on local precipitation.…”

“…The Southeast Trade Winds (SETWs) are present throughout the year in the south Indian Ocean and are also an important determinant for the variability of precipitation on the island. Fowdur et al (2014), who investigated the precipitation of Mauritius, also observed the effect of windfields on local precipitation.…”

Forecasting Rainfall in Mauritius using Seasonal Autoregressive Integrated Moving Average and Artificial Neural Networks

“…A recent work by (Fowdar et al, 2014) was done on the classification of rainfall patterns in Mauritius using principal component analysis. However the development of forecasting techniques for rainfall prediction has attracted much interest across the globe.…”