SIR-Bの方向性海洋波スペクトルと航空機スキャンレーダースペクトルの比較
まとめ
シャトル画像レーダー-B (SIR-B) データは,空中レーダーと比較して波長と方向を含む海洋波の特性を正確に推定しました. 波のモデルは方向性バイアスを示し,海洋波の研究のための衛星レーダーの価値を強調しました.
科学分野:
- 海洋学 海洋学とは
- リモートセンシング (リモートセンサー)
- 地質物理学 地質物理学とは地質物理学です.
背景:
- 方向的な海洋波のスペクトルは,波動力学と海洋活動への影響を理解するために不可欠です.
- 衛星搭載のレーダーシステムは,海洋表面状態の遠隔感知のためのユニークな視点を提供します.
研究 の 目的:
- シャトル画像レーダー-B (SIR-B) のLバンド画像から得られた方向性海洋波スペクトルを,独立した空中レーダー推定値と比較するために.
- 波長,方向,スペクトル形状などの波のパラメータを捕捉するSIR-Bの精度を評価する.
主な方法:
- チリ沖の太平洋上空で収集されたSIR-B Lバンド画像の分析.
- SIR-Bから派生した波スペクトルの比較と,2つの空中スキャンレーダーからのデータ.
- アメリカ海軍のグローバルスペクトル海洋波モデル予測に対する検証.
主要な成果:
- SIR-Bから派生したスペクトルは,波長,方向,スペクトルの形状の合理的な見積もりを,3メートルから5メートルまでの波の高さのある海の状態のために提供しました.
- SIR-B画像の強度変数スペクトルは,距離を移動する波の航空機の斜面変数スペクトルと密接に一致しました.
- 米海軍の波形モデルは,支配的な波数の有意なバイアスを示さなかったが,方向性バイアスは約30度であった.
結論:
- SIR-B Lバンド画像は,方向的な海洋波のスペクトルを導出するための貴重なツールです.
- SIR-Bのデータは,純粋にアジムット方向を移動する波を含む,さまざまな波システムを正確に特徴付けることができます.
- 波モデルとの不一致は,方向性波の予測におけるモデル改善の分野を強調する.
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