Past and future climate variability analysis in bhutan

The escalating local impacts of climate change are a pressing global concern, particularly in regions vulnerable to global warming, like the Hindu Kush Himalayan region. Bhutan, recognised as one of the world’s most climate-vulnerable nations, faces extensive socio-economic damages due to climate change, posing significant recovery challenges. Climate change studies using satellite and hybrid data with Global Climate Models often amplify uncertainty, leading to exaggerated results. So, to understand the climate variability in Bhutan, we analysed historical temperature and precipitation using ground station data. We utilised the Mann–Kendall test and Sen’s slope analysis for trend assessment, continuous wavelet transform for periodicity detection, and cross wavelet transform for correlation analysis with atmospheric oscillations. The future climate projections were evaluated based on best-fit bias-corrected Coupled Model Intercomparison Project Phase 6 Global Climate Models data under the various Shared Socio‐Economic Pathways. The historical time series revealed, in general, a decreasing trend in rainfall. The maximum temperature showed a warming trend mostly above the elevation of 1000 m above mean sea level, while the minimum temperature showed a decreasing trend. However, the mean annual temperature and precipitation are expected to increase. The country could warm up from 1.7ºC to 3.3ºC under various Shared Socio‐Economic Pathways. The periodicity analysis of wavelets reveals that most stations showed higher covariance with the Indian Ocean Dipole and Elnino Southern Oscillation, followed by North Atlantic Oscillation, with 9–14 months periodicities. The findings of the past and future climate analysis presented in this study are expected to play a significant role in protecting the beautiful ecosystem of Bhutan as a whole. Additionally, the findings could assist policymakers in formulating adaptation strategies for addressing climate change impacts, enabling them to implement essential measures to transform Bhutan into a climate-resilient country.