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2026 Vol.59, Issue 1

Review

Hydrological applications of polarimetric SAR: Current progress, knowledge gaps, and future directions

편극 SAR의 수문학적 활용: 현황, 개선점 및 향후 방향

Hyunsu Parka
,
SeokHwan Hwangb
,
Jungsoo Yoonc
,
Narae Kang, d
,
Seokhyeon Kime*
박 현수a
,
황 석환b
,
윤 정수c
,
강 나래d
,
김 석현e*
aMaster’s Course, Department of Civil Engineering, Kyung Hee University, Yongin, Korea
bResearch Fellow, Department of Hydro Science and Engineering Research, Korea Institute of Civil Engineering and Building Technology, Goyang, Korea
cSenior Researcher, Department of Hydro Science and Engineering Research, Korea Institute of Civil Engineering and Building Technology, Goyang, Korea
dSenior Researcher, Department of Hydro Science and Engineering Research, Korea Institute of Civil Engineering and Building Technology, Goyang, Korea
eProfessor, Department of Civil Engineering, Kyung Hee University, Yongin, Korea
a경희대학교 사회기반시스템공학과 석사과정
b한국건설기술연구원 수자원하천연구본부 연구위원
c한국건설기술연구원 수자원하천연구본부 수석연구원
d한국건설기술연구원 수자원하천연구본부 수석연구원
e경희대학교 사회기반시스템공학과 교수
*Corresponding Author
31 January 2026. pp. 1-15
PDF XML Citation
Abstract

Polarimetric Synthetic Aperture Radar (PolSAR) provides unparalleled capability to disentangle surface, volume, and double-bounce scattering, enabling physically grounded observation of hydrological processes that cannot be captured by optical or single-pol SAR systems. Leveraging this strength, recent studies have demonstrated PolSAR’s expanding value in quantifying soil moisture, detecting flooded vegetation, characterizing wetland hydro-ecological dynamics, and monitoring cryospheric states including snow, ice, and permafrost. This review consolidates these advances by linking the underlying polarimetric scattering principles with the hydrological variables they enable, and critically evaluates their performance across diverse land-surface and vegetation conditions. Despite notable progress, major challenges remain—including persistent quantitative uncertainties, complex mixed scattering in heterogeneous terrain, and limited operational readiness of current, computation-heavy algorithms. We highlight emerging pathways that can fundamentally reshape PolSAR’s role in hydrology, particularly through machine learning, multi-sensor fusion with optical, InSAR, and radiometric missions, and the transformative observational capabilities offered by next-generation L-/P-band satellites such as NISAR and BIOMASS. These developments position PolSAR as a central component of future operational and predictive hydrology.

Keywords
Polarimetric SAR
Polarimetric decomposition
Hydrological remote sensing
Soil moisture retrieval
Flood mapping

편파 합성개구레이다(PolSAR)는 표면·체적·이중 반사 성분을 분리해낼 수 있는 독보적 능력을 바탕으로, 광학이나 단일 편파 SAR으로는 관측이 어려운 수문 과정을 물리적으로 정합성 있게 포착할 수 있다. 이러한 강점을 기반으로 최근 연구들은 토양 수분의 정량화, 침수 식생 탐지, 습지 수문–생태 동역학 분석, 적설·빙하·영구동토층을 포함한 빙권 모니터링 등 다양한 분야에서 PolSAR의 활용 가치를 입증해 왔다. 본 총설은 이러한 발전을 체계적으로 정리하고, 편파 산란 원리와 분해 기법이 각 수문 변수 도출과 어떻게 연결되는지를 종합적으로 검토한다. 아울러 다양한 지표·식생·대기 조건에서 PolSAR 기반 기법이 보여주는 성능을 평가하고, 여전히 남아 있는 정량적 불확실성, 복합 지형에서의 혼합·방향성 산란, 높은 계산 비용으로 인한 낮은 운용성 등의 한계를 비판적으로 논의한다. 마지막으로 기계학습, 광학·InSAR·마이크로파 복사계와의 다중 센서 융합, NISAR·BIOMASS 등 차세대 L-/P-밴드 위성의 등장과 같은 최근 흐름이 향후 PolSAR의 실시간·예측 수문학적 활용을 어떻게 확장할 수 있는지를 제시한다.

키워드
편극 SAR
편파 분해
수문 원격탐사
토양수분 추정
침수 지도화
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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 :1
  • Pages :1-15
  • Received Date : 2025-11-14
  • Accepted Date : 2025-12-04
  • DOI :https://doi.org/10.3741/JKWRA.2026.59.1.1
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