Association of Climate Change to Landslide Vulnerability and Occurrences in Bhutan

Abstract

Bhutan exhibits diverse climatic belts with seasonal unpredictable climatic events such as rainfall, varying temperature, hailstorm and snow. The mentioned parameters have been significantly recorded over the past years. In recent studies, meteorological records of southern regions indicate an exponential increase in temperature and rainfall. Some infrequent snows and hailstorms were also observed lately in this region followed by heavy rainfall during winter. Such an increase in rainfall intensity gives rise to occurrences of natural hazards. Hazards such as landslides, mudflows, debris, rock falls and flash floods occur every monsoon causing substantial damage to lives and infrastructures. These events are recorded and a systematic inventory is developed by the organizations such as the National Centre for Hydrology and Meteorology (NCHM) and the Department of Geology and Mines (DGM). However, these data are limited and do not comprise of all historical events, and hence no significant integration of climate change and natural disaster have been scientifically conducted. In this research study, historical climatic data and landslide occurrences in Bhutan have been analysed to explore potential correlations between meteorological scenarios and hazard occurrences. Therefore, field data and satellite data of climate are investigated to explore the landslide triggering elements, and the potentiality of satellite data is assessed to validate the landslide records of the past. The current study further explores the variation of satellite and field measurement with the Gumbel distribution to understand the climate change in such a complex Himalayan region. The results thus obtained will give a greater perspective on the impact of distribution, frequency, occurrence and magnitude of landslides through empirical association in minimizing the risk and implications to socio-economic activities.KeywordsClimate changeLandslideGumbel distributionReturn periodBhutan