Thank you very much

Yes you can use that GRD product. But some other work I required phase information so from GRD that was missing. Thats way I showed with SLC.

Multilooking in synthetic aperture radar (SAR) is a processing technique that involves averaging multiple looks (or images) of the same area to improve the overall image quality. The purpose of multilooking in SAR data is to reduce the speckle noise, which is a type of noise that occurs in SAR images due to the interference of the radar waves with the surface of the target. By averaging multiple looks, multilooking can increase the signal-to-noise ratio and improve the visual interpretation of the data. Additionally, multilooking can enhance the resolution of the image, providing more detailed information about the target area. Multilooking can also help to reduce the computational burden of processing SAR data by reducing the overall amount of data that needs to be processed. This makes it possible to process larger areas of SAR data more efficiently, which can be useful in applications such as remote sensing and geospatial analysis.

Sentinel Synthetic Aperture Radar (SAR) data provides valuable information for flood mapping due to its ability to penetrate clouds and capture images even in the absence of visible light. SAR data can be acquired in two polarizations: vertical transmit and vertical receive (VV) and vertical transmit and horizontal receive (VH). The VV polarization is better for flood mapping because it provides higher backscatter compared to VH. Backscatter refers to the amount of energy that is reflected back to the sensor by the surface being imaged. In the case of water, the surface is smooth and reflective, which means that VV polarization can capture more reflected energy and provide a stronger signal compared to VH polarization. Furthermore, VH polarization can be affected by vegetation cover or rough terrain, which can scatter the radar signal and reduce its intensity, making it less effective for flood mapping. VV polarization, on the other hand, is less sensitive to these factors and provides a more accurate representation of flood extent. Overall, the VV polarization of Sentinel SAR data is preferred for flood mapping due to its higher backscatter and reduced sensitivity to vegetation and terrain effects.

​@@spaceremotesensingandgis5626when VV polarization is better for flood, so the VH polarization is better for what? 🤔

water area you can get from previous image. Extract that and create mask. use that mask over flooded area then you will get exact flooded area.