Unpacking Future Climate Extremes and their Sectoral Implications in Western Nepal

Abstract

Existing climate projections and impact assessments in Nepal only consider a limited number of generic climate indices such as means. Few studies have explored climate extremes and their sectoral implications. This study evaluates future scenarios of extreme climate indices from the list of Expert Team on Sector-specific Climate Indices (ET-SCI) and their sectoral implications in the Karnali Basin in western Nepal. First, future projections of 26 climate indices relevant to six climate-sensitive sectors in Karnali were made for the near (2021–2045), mid (2046–2070), and far (2071–2095) future for low- and high-emission scenarios (RCP4.5 and RCP8.5, respectively) using bias-corrected ensembles of 19 regional climate models from the COordinated Regional Downscaling EXperiment for South Asia (CORDEX-SA). Second, a qualitative analysis based on expert interviews and a literature review on the impact of the projected climate extremes on the climate-sensitive sectors was undertaken. Both the temperature and precipitation patterns are projected to deviate significantly from the historical reference already from the near future with increased occurrences of extreme events. Winter in the highlands is expected to become warmer and dryer. The hot and wet tropical summer in the lowlands will become hotter with longer warm spells and fewer cold days. Low-intensity precipitation events will decline, but the magnitude and frequency of extreme precipitation events will increase. The compounding effects of the increase in extreme temperature and precipitation events will have largely negative implications for the six climate-sensitive sectors considered here.

Detection and attribution of the spatiotemporal trend of climatic disaster impacts and vulnerability in Nepal

“…Nepal is among the top 10 countries worldwide most affected by climatic disasters in the past two decades (Eckstein et al 2021). Extreme precipitation events, such as the numbers of heavy precipitation days and consecutive wet days, are increasing in many parts of the country, especially in the western half (Karki et al 2017;Chapagain et al 2021), and warm days and nights are occurring more frequently across the country (DHM 2017). Previous studies have observed increasing trends in the frequency of climatic disasters and mortality from climatic disasters in Nepal (Petley et al 2007;Aryal 2012;Elalem and Pal 2015;Aksha et al 2018;Adhikari and Tian 2021;MoFE 2021).…”