Abstract:
There are no discernible patterns concerning drought and flood hazards in Sri Lanka; some areas
have experienced more disasters than others. The objective of this study is to identify the spatial
patterns of drought and flood hazards that exist in this region. Monthly, seasonal, and annual
climatic data were gathered from thirteen stations, covering the period from 1972 to 2022. The
Standardized Precipitation Index (SPI) was employed to examine each station's drought and flood
hazards from 1972 to 2022. The Arc GIS 10.4 Krigging method was utilized to identify the spatial
variations of the drought and flood hazards. During the South West Monsoon Season, severe
droughts were detected in Vavunikkulam, Akkarayankulam, Murunkan, and Pavatkulam. Extreme
floods were common during the First Inter Monsoon Season; three occurrences were noted at
Iranaimadu, Thirunelveli, Pallavarayankaddu, and Nainathivu stations in the Northern region,
identified through the SPI method. During the Second Inter Monsoon Season, two extreme floods
in Thirunelveli, two in Vavuniya, and three in Murungan and Akkarayankulam stations were
identified alongside seven severe droughts at Nainathivu and five at Vavuniya. During the North
East Monsoon Season, three severe floods were identified in Akkarayankulam, three in
Ambalapperumalkulam, three extreme floods in Pallavaraykaddu, three severe floods in
Muththaiyankaddu, four severe floods in Vavunikkulam station, and three severe floods in
Vavuniya in the Northern region of Sri Lanka. Some areas in the Northern Region of Sri Lanka
have been affected several times spatially by both floods and droughts. The eastern parts of the
study area have more flood hazards, while the western parts have more droughts, according to
70% of the people surveyed. Furthermore, the frequency of flood occurrences decreases gradually
in the direction from east to west, while that of droughts decreases gradually from west to east.
