13th IGSC Presentation

Presentation for the 13th East-West Center Graduate Students’ Conference, February 13-15, Honolulu, Hawaii

Title: Climate change and floods in the Nepali Tarai: Perceptions and climatic evidence

Abstract: This paper presents the preliminary findings of a background study and pilot interviews for an ongoing PhD research on exploring the dynamics of water-induced hazards, livelihood and migration in Nepal’s plains. The Himalayan glacial melt, coupled with any changes in precipitation, temperature and seasonal variability will impact water flowing through the hills and the plains of Nepal before merging into larger rives in the sub-continent thus impacting livelihoods of millions before reaching the ocean. Even though changes in climate is widely accepted, the direction and magnitude of change has spatial variations. To capture the spatial distribution  in the impacts and adaptation strategies from floods, mapping of flood incidents was done using DesInventar database which lists records of floods from published news sources with records going back to 1971. With a view of capturing variations at the smallest possible administrative boundary, the name of village development committees (VDCs) were extracted from the records wherever possible. As not all records specify the name of the village and some records mention multiple villages but not the names, some records could not be matched to the village level location. Overall, around 5% of the records could not be matched. Such a village level data is also useful for adaptation planning at the local level and provide important learning for other regions. The incidence maps show the Tarai as hotspot of flooding incidents. For this research, the focus was on the eastern districts of Jhapa, Morang and Sunsari where clusters of VDCs with high flood incidence. Any change in precipitation pattern will impact upon a huge section of the Nepali population as a majority of livelihoods are closely tied to rain-fed agriculture with virtually no mechanization. Precipitation is also the cause of major hazards in the region through landslides, flash floods and crop inundation. For finding evidence of climatic change, an analysis of temperature and precipitation data from seven stations in the region was conducted. The analysis on daily rainfall records based on monotonic trend estimate using seasonal Mann Kendall and generalized additive mixed model (GAMM) revealed no statistically significant trends in annual rainfall, excess rainfall days, good rainfall days and dates of monsoon onset. This confirms some recent researches on data from other stations in central and eastern Nepal and contradicts some research findings. Similarly, analysis of temperature data using monotonic trend estimate shows statistically significant increase in daily minimum and daily mean temperature in all three stations. Daily maximum temperature shows statistically significant increase in Gaida Kankai station whereas a statistically significant decrease in Tarahara station. The pilot interviews of the residents from Jhapa district reveal that the locals are aware of the changing climate as they have perceived warming trend and rise in flood incidents.