Spatial and temporal variations in temperature and precipitation trends in South Korea over the past half-century (1974–2023) using innovative trend analysis

Abstract

This study analyzed temperature and precipitation from 60 meteorological stations during a half-century (1974–2023) using the Innovative Trend Analysis (ITA) to explore the spatial and temporal trends across South Korea. The ITA illustrated the trends graphically, and the Mann-Kendall (MK) test added statistical significance to these findings, allowing us to better understand climate changes over the past five decades. The ITA analysis showed a statistically significant monotonic warming trend in temperature at nearly all of the stations. While annual and seasonal changes were found to be substantial, the most relative increases were reported during the spring and summer months. There were quite clear spatial and seasonal differences in precipitation trends. The Han River and Jeju Island areas showed significant increases in precipitation during summer and autumn, which may be associated with intensified monsoonal activity. Our findings revealed a consistent warming signal in all regions and significant regional climate variability. The observed temperature increases, especially in the spring season, are likely to have significant impacts on crop yield and altered growing season due to increased heat stress, increased water demand for various activities affecting water resources, heightened risks to public health from heatwaves and broader impacts on societal well-being such as increased energy demands as well as economic costs associated with climate adaptation measures. The complex precipitation patterns revealed the influence of regional topography and oceanic drivers in modulating climate variability in South Korea, which differs from patterns seen in more continental regimes.