High spatial and temporal variation in precipitation in South Korea leads to an increase in the frequency and duration of drought. In this study, the spatial characteristics of temporal trends for precipitation and drought severity time series were analyzed at 55 stations across South Korea for the period 1980–2015. This study also reviewed the usefulness of different trend tests while addressing the issue of serial correlation, which has often received less attention in previous studies. Results showed that most significant trends in precipitation were detected along the south coast of South Korea, especially during winter, late spring and summer, whereas no significant trend was detected in annual precipitation. The Sen’s slope of the trends increased from January to August and decreased from August onward. Principal component analysis applied on Standardized Precipitation Index (SPI) at a 12-month time scale divides the whole of South Korea into four subregions with different temporal behaviors of drought severity. Moreover, drought severity showed a significant increasing trend, mainly on the northeast coast. Drought frequency analysis showed more frequent droughts in late winter, early spring and early autumn, with less frequent droughts in summer.

In order to prepare for floods and droughts that occur as a result of climate change, various studies in water-related fields are being carried out in various countries around the world. Among them, special attention is being paid to the low-impact development (LID) technique. This study measured the annual maximum daily rainfall data from 2019 to 2100 by climate change scenario, which is the annual maximum daily rainfall series observed for rainfall stations, and tested the hydrological data using statistical analysis. After determining whether the data could be analyzed, the probability distribution was selected, and the parameters of the selected probability distribution were calculated using the L-moment method for each rainfall station. The probabilities of rainfall data were derived using GEV distribution, and the United States Environmental Protection Agency Storm Water Management Model (SWMM), a runoff simulation program, was used to compare and analyze the runoff reduction rate before and after the installation of a permeable pavement as an LID facility. The results of the analysis showed that representative concentration pathway (RCP) 4.5 and RCP 8.5 had the effect of reducing the runoff for more than 100 years at a 30% reduction rate compared with before installation.

This study aimed to establish an assessment system for rural water-cycle soundness across standard watersheds in Korea and to determine priorities for project implementation. As climate change, water-quality deterioration, and population aging in rural areas intensify, the need for an integrated approach to rural water management has become increasingly important. The study was structured into five sectors: water use, water safety, water environment, carbon neutrality, and water-friendly amenity. Sector-specific indicators were selected, and normality assessment, standardization, and factor analysis were conducted to verify indicator suitability. Weights were estimated using principal component analysis (PCA) to enhance the objectivity of the evaluation. A total of 825 standard watersheds were assessed, and sectoral indices were integrated to derive a rural water-cycle soundness index, which was subsequently classified into five grades. Based on the overall grades and sector-specific results, the priority of each standard watershed for implementing rural water-cycle projects was determined. The proposed framework provides a scientific basis for identifying vulnerable rural areas from a water-cycle perspective and supports policy responses. It may also contribute to future rural water management policies and disaster response strategies.

This study analyzes the social and economic characteristics of an area affected by chemical emission facilities and proposes policy measures to respond to social disasters such as hazardous chemical emission accidents. Even within the area affected by chemical discharge facilities, social and economic disparities existed depending on the proximity to the chemical discharge facility, child population ratio, and land value. However, the elderly population ratio decreased. It is believed that the presentation of response plans based on the study’s analysis will contribute to protecting people's health and property, which is the ultimate goal of chemical management.