Impacts of Climate Change on Temperature and Precipitation in Nepal: Projections and Bias Correction

Hari Prasad Dhital

Institute of Engineering, Purwanchal Campus, Tribhuvan University

Madhav Joshi

Institute of Engineering, Kathmandu Engineering College, Tribhuvan University

Nabin Budhathoki

Institute of Engineering, Kathmandu Engineering College, Tribhuvan University

*Corresponding author: haridhital34@gmail.com

Abstract

Climate change is likely to have a significant impact on Nepal, affecting its infrastructure, agriculture, and water resources. This study created day-to-day bias-corrected data of precipitation (ppt), maximum temperature (tmax) and minimum temperature (tmin) at 0.25° spatial resolution for Nepal using 7 CMIP6-GCMs under two shared socioeconomic pathways, SSP245 and SSP585. The bias-corrected datasets were produced using an empirical robust quantile mapping method for ppt and quantile mapping with linear transformation function method for tmax and tmin. The bias-corrected dataset was evaluated by comparing it against observed data for the mean values of ppt, tmax and tmin. Our bias-corrected projections reveal a warming of 4-6°C and an increase in ppt of 40-60% by the end of the 21st century. These changes will have a significant impact on Nepal's climate, environment, and people. The bias-corrected projections can be used to assess the impact of climate change in Nepal and to develop adaptation strategies.

Keywords: Climate change, Bias-Correction, CMIP6, Global Climate Model, Nepal

Received 20.07.2023; Revised 18.09.2023; Accepted 02.11.2023

Cite This Article: Dhital, H.P., Joshi, M., & Budhathoki, N. (2023). Impacts of Climate Change on Temperature and Precipitation in Nepal: Projections and Bias Correction. Journal of Sustainability and Environmental Management, 2(4), 203-212. doi: https://doi.org/10.3126/josem.v2i4.61020

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