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2026 Vol.59, Issue 6 Preview Page
Quantifying drought propagation and migration pathways using gridded drought indices and spatiotemporal clustering

격자기반 가뭄지수와 시공간 군집분석을 활용한 가뭄 전파 및 이동경로 분석

Young-Sik Muna
,
Won-Ho Namb*
,
Ashok Mishrac
문 영식a
,
남 원호b*
,
Ashok Mishrac
aSenior Researcher, National Agricultural Water Research Center, Hankyong National University, Anseong, Korea
bProfessor, School of Social Safety and Systems Engineering, Institute of Agricultural Environmental Science, National Agricultural Water Research Center, Hankyong National University, Anseong, Korea
cProfessor, Zachry Department of Civil and Environmental Engineering, Texas A&M University, Texas, USA
a한경국립대학교 국가농업용수연구센터 선임연구원
b한경국립대학교 사회안전시스템공학부 교수
c텍사스 A&M 대학교 토목환경공학과 교수
*Corresponding Author
30 June 2026. pp. 561-573
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Abstract

Drought is not a static phenomenon confined to a specific location but a dynamic spatiotemporal process characterized by onset, expansion, migration, and decay. This study investigates the propagation and migration characteristics of drought events in South Korea using grid-based drought indices and the spatiotemporal clustering algorithm ST-DBSCAN. Monthly SPI-6 values were derived from satellite-based precipitation data (CHIRPS V3.0), and drought grids were identified to extract spatiotemporally connected drought clusters. Three large-scale drought events (1993-1996, 2000-2003, and 2013-2016) were selected to analyze the evolution of drought events across sequential stages, including onset, expansion, peak, and decay. The migration pathways and directional behavior of drought cluster centroids were quantified to reveal spatiotemporal dynamics. Results show that drought events consist of multiple interacting clusters that evolve sequentially and overlap in space and time, rather than forming a single contiguous structure. Across all representative events, northward migration was dominant, while additional movements toward the northeast, northwest, and south were also observed, indicating multidirectional propagation patterns. These findings demonstrate that drought migration exhibits both directional tendencies and complex spatial dynamics. By conceptualizing drought as a dynamic migrating system, this study provides a new perspective on drought propagation processes. The proposed approach has strong potential to enhance drought monitoring and early warning systems by incorporating migration dynamics and can be extended to the development of AI- and machine learning-based predictive models for drought evolution.

Keywords
Drought propagation
Drought migration
Spatiotemporal clustering
ST-DBSCAN
Grid-based drought index
SPI
CHIRPS

가뭄은 특정 지역에 국한된 정적인 현상이 아니라, 시간의 흐름에 따라 발생, 확산, 이동, 소멸하는 시공간적 동적 과정이다. 본 연구에서는 격자 기반 가뭄지수와 시공간 군집분석 기법인 ST-DBSCAN을 활용하여 우리나라 가뭄의 전파 및 이동 특성을 정량적으로 분석하였다. 이를 위해 위성 기반 강수 자료(CHIRPS V3.0)를 이용하여 월 단위 SPI-6를 산정하고, 가뭄 격자를 추출한 후 시공간적으로 연결된 가뭄 군집을 식별하였다. 대규모 가뭄 기간(1993-1996, 2000-2003, 2013-2016)을 선정하여 가뭄의 발생, 확산, 피크, 소멸 단계별 진화를 분석하고, 군집 중심의 이동 경로 및 방향성을 정량적으로 평가하였다. 분석 결과, 가뭄은 단일 군집이 아닌 다수의 군집이 시간적으로 연속적으로 발생하고 상호 중첩되면서 하나의 가뭄 사건을 형성하는 동적 시스템으로 나타났다. 또한 대규모 가뭄 사건에서 북향 이동이 지배적으로 나타났으며, 일부 군집에서는 북동, 북서 및 남향 이동이 함께 나타나는 다방향성이 확인되었다. 이러한 결과는 가뭄 이동이 특정 방향성을 가지면서도 복합적인 시공간 전파 특성을 보인다는 것을 시사한다. 본 연구는 가뭄을 정적인 현상이 아닌 이동하는 동적 시스템으로 해석함으로써 가뭄 전파 메커니즘에 대한 이해를 확장하였다. 또한 제안된 접근법은 가뭄 이동 특성을 반영한 모니터링 및 조기경보 체계 구축에 활용될 수 있으며, 향후 인공지능 및 머신러닝 기반 가뭄 이동 경로 예측 모델 개발로 확장될 수 있다.

키워드
가뭄 전파
가뭄 이동
시공간 군집분석
ST-DBSCAN
격자 기반 가뭄지수
SPI
CHIRPS
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Information
  • Publisher :KOREA WATER RESOURECES ASSOCIATION
  • Publisher(Ko) :한국수자원학회
  • Journal Title :Journal of Korea Water Resources Association
  • Journal Title(Ko) :한국수자원학회 논문집
  • Volume : 59
  • No :6
  • Pages :561-573
  • Received Date : 2026-03-31
  • Revised Date : 2026-04-15
  • Accepted Date : 2026-04-17
  • DOI :https://doi.org/10.3741/JKWRA.2026.59.6.561
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