Rainfall characteristics during pre- and post-onset of local climate change in Aceh Besar District, Indonesia

Abstract

Climate change caused by global warming, which is characterized by increasing temperatures on the earth’s surface, is the biggest problem in the world today. This study attempts to examine how local climate change has affected the characteristics of rainfall in Aceh Besar District, which is situated in the far north of Indonesia’s Sumatra Island. 2001 was assumed to be the onset of local climate change in the region. Using EasyFit, probability distribution that best fits the rainfall data during the pre- and post-onset of climate change is chosen. The results indicated that the annual rainfall amount has increased over the past decade. The probability of receiving an annual total rainfall exceeding the long-term average (1700 mm) has increased significantly after the local climate change. Meanwhile, although the lowest and highest amounts of annual maximum daily rainfall for pre- and post-onset periods remain the same, the frequency of the maximum daily rainfall in a year greater than 140 mm/day was doubled during the post-onset period. Consequently, local climate change has increased the expected amount of annual maximum daily rainfall for return periods of 2, 5, and 10 years.