Trend Analysis for Annual Rainfall Data in Dili, Timor-Leste using Mann Kendall Method

  • Aderita Takeleb Dili Institute of Technology
  • Miguel Antonio Ximenes Dili Institute of Technlogy
Keywords: Trend analysis, rainfall, climate change, statistical model, Mann-Kendall, water resource.


Rainfall is a key element of the hydrological cycle, therefore detecting trends of rainfall data can be used as information for understanding climate change. The trend of rainfall data in Dili needs to be made to identify changes in the hydrological climate system. The purpose of this study was to determine the rainfall trend in Dili using the Mann-Kendall test. The longest and most complete daily rain data is from stations installed at Dili Airport. Available data is from 1953 - 2017. The rainfall trend obtained can serve to detect possible changes in rainfall in Dili for the coming years. The linear trend shows that the rainfall in Dili tends to decrease every year. According to the Mann-Kendall test, The Aeroporto Dili annual rainfall trends are statistically insignificant.  This shows that there is a variation in the daily rainfall in one year, which can be different from other years due to fluctuations in weather and seasons. Although the reduction in rainfall every year is not very significant, it has implications for climate change that affects to water availability. Therefore, the information on trends in annual rainfall data can be used as a reference in dealing with impacts of climate change and water resources available in Dili.


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