Hello. I am very new to this genre of remote sensing algorithms. I have a query regarding the TSM (g/m³) output calculated by C2RCC in ESA SNAP.
Since the TSM values we get are in g/m³, so it is visible that it is 3D - it considers depth data. But I do not give any depth input. So how and from where does this algorithm collect depth data? And how reliable is that depth value?
The C2RCC algorithm does not require depth data input; TSM concentration is estimated based on surface reflectance only (+ e.g., meteorological data).
Even if the TSM unit is g/m³, it does not directly imply a 3D consideration (depth). The TSM value represents a surface or near-surface concentration observed by satellite sensors.
In real life, TSM concentration varies with depth, but C2RCC has been trained with synthetic data where water properties are uniform with depth and the depth is infinite, or at least way larger than the depth light can penetrate. Therefore, you can take the C2RCC TSM concentration to be the TSM concentration of a fully mixed homogenous surface layer that yields the same remote sensing signal as what is being observed.
Thank you very much 