Graphical display and statistical modeling of temperature changes in tropical and subtropical zones

Abstract

Climate change, particularly rising temperature, is one of the important environmental problem facing the world today. This study aims to identify trends and patterns of temperature change in tropical and subtropical zones using a statistic model. Data were obtained from the climate research unit from 1973 to 2008, comprising 252 regions of 10° by 10° grid-boxes between latitudes 35° north and south. The data were filtered with a second order autoregressive process to remove autocorrelations between temperature lags. Factor analysis was used to classify monthly average temperature anomalies into larger regions by taking into account the correlation between adjoining regions. Simple linear regression models were then fitted to the data within these larger regions. The result showed that the temperatures in these 15 larger regions have increased the most (by at least 0.065°C per decade) in the North Atlantic Ocean and the central and the north of Africa. Lower increases (0.045–0.064°C per decade) occurred in Southeast Asia, the Indian Ocean and the North Pacific Ocean.

Keywords

• linear regression model
• autocorrelation
• factor analysis
• climate change
• tropical zones