Abstract:
Understanding the changes of long-term rainfall is vital for water resources management
and climate mitigation strategies development. This study aims to evaluate the annual, seasonal, and
monthly rainfall trends of the northern region of Sri Lanka from 1970 to 2019. The Mann-Kendall and
Sen's slope tests have been used to analyze the trend and magnitude changes, respectively. The results
show that the historical annual rainfall of Northern Sri Lanka has increased from 18.76 mm/decade to
37.68 mm/decade from 1970 to 2019. As per the seasonal pattern, the rainfall of the northeast monsoon
has been reduced, while South west Monsoon rainfall has increased gradually in the Northern Region of
Sri Lanka. There are fluctuating patterns in the monthly rainfall pattern, and November dominates in the
monthly rainfall pattern, receiving more than 350 mm as the average. Changes in the rainfall pattern of
the study area impact the physical and economic living environment.
