Towards algorithm improvement of satellite remote sensing for soil moisture by modelling relationships of dielectric behavior and soil-water-retention characteristics

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K04619
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 22040:Hydroengineering-related
• Research Institution: Okayama University
• Principal Investigator: Tsujimoto Kumiko 岡山大学, 環境生命自然科学学域, 研究准教授 (80557702)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 土壌水分量 / 衛星観測 / 誘電率 / 保水性 / 輝度温度 / マイクロ波リモートセンシング / 放射伝達モデル / 陸面データ同化

Outline of Final Research Achievements

This study aims to deepen the understanding of the relationship between soil water retention characteristics and soil dielectric properties, and thereby improve the accuracy of microwave remote sensing of soil moisture from satellite. By conducting laboratory measurements of soil permittivity taken from various locations in Japan and Cambodia, a new dielectric model was developed which links the dielectric behavior of wet soils to their water retention characteristics. The effect of applying the newly developed dielectric model for microwave remote sensing of soil moisture was quantified for various soil types across the world, with information on the comparison with existing dielectric models.

Free Research Field

水工学，水文学，大気－陸面過程，土壌物理学

Academic Significance and Societal Importance of the Research Achievements

世界各地の土壌水分量のモニタリングは，気候変動下の水災害に対する早期警戒策を講じる上で有用な情報源となる．本研究では，土壌の保水性と関連付けた新たな誘電率モデルを開発することで，人工衛星による土壌水分量推定アルゴリズムの改良を行った．これにより，土壌水分を衛星観測により「モニタリング」することと，観測の無い日時に対して「シミュレーション」することを整合的に繋いでモデル化する枠組みが構築された．