Projection of future hot weather events and potential population exposure to this in South Korea

Abstract

Heat waves, often caused by consecutive severe hot weather events, are responsible for the majority of medical costs associated with climate change in South Korea. In this study, we obtained a regional climate change scenario (RCP4.5) for South Korea, with 7.5 × 7.5 km horizontal resolution and extending up to 2100, by dynamically downscaling from results of the Community Earth System Model (CESM) with the Weather Research and Forecasting (WRF) model. We analyzed hot weather events (daily maximum temperature > 33°C) in summer (June−August), focusing on changes in extent and frequency. According to our analysis, the area exposed to hot weather events in August will expand to cover ~70% of the nation in the middle of this century, with a rate of increase of 0.24% yr −1. We calculated the population exposed to hot weather events in Korea, considering both spatial coverage and number of event days. Population exposure was projected to increase almost 3-fold, from 26% of the national population during the 2010s to 72% during the 2090s. In particular, exposure of the elderly population (> 65 yr old), who are particularly vulnerable, was expected to rapidly increase, with ~22% of the national population (~10.4 million people aged > 65 yr) affected in the middle of this century when we considered the future projection of rapid aging of the South Korean population structure. Our projection of extensive hot weather events starting from the middle of the 21st century suggests the need for urgent government long-term measures and enforcement to ensure an early response to extreme weather events in Korea.

Effects of Environmental Change on Human Health: A Descriptive Economic Analysis

“…Extreme weather-related mortality in the United States shows that two third of total deaths are due to excessive natural heat and remaining are due to excessive cold and others (Jiang et al, 2015), but, might be negligible, mortality from the thunderstorm, hot events and heavy rainfall and other climatic induced disasters has slightly appeared in Nepal. Recently it has been predicted that extreme hot weather events may cover 72% of the national population of Korea by 2090s if current trend remains the same (Shim et al, 2017). Unexpected excess rainfall in Europe has made water contaminated with Arsenic and Antimony, subsequently degrading to the human health through food chain (Cann et al, 2013).…”

A Review of Effects of Environmental Change on Human Health

“…Extreme weather-related mortality in the United States shows that two third of total deaths are due to excessive natural heat and remaining are due to excessive cold and others (Jiang et al, 2015). Recently it has been predicted that extreme hot weather events may cover 72% of the national population of Korea by 2090s if current trend remains same (Shim et al, 2017). Unexpected excess rainfall in Europe has made water contaminated with Arsenic and Antimony, subsequently degrading to the human health through the food chain (Cann et al, 2013).…”

Elucidating Uncertainty in Heat Vulnerability Mapping: Perspectives on Impact Variables and Modeling Approaches

“…South Korea is one of the countries experiencing rapid aging globally, with the proportion of the elderly population increasing from 7.2% in 2000 to 16.6% in 2021 [26]. Sim et al calculated the exposure risk of the population to heatwaves based on future scenarios of heatwave days and national population estimates, forecasting that rapid aging would be a significant factor in increasing the exposure risk to heatwaves [27]. An increase in the elderly population in the future is expected to escalate the scale of heatwave damage alongside an increase in extreme weather phenomena [28].…”