Hello, I’m working with SAR images to identify internal waves in the ocean, when I use the amplitude VV image I get a pretty clear image of internal waves as seen in figure 1. The problem is everywhere I see (articles, forums, etc) says that VH polarization is better for ocean view, but the figure 2 is the VH image of the same region that I did the same processing steps, and as you can tell I can’t see any of that internal waves. Am I doing something wrong? Is VH really better than VV for this purpose? Any bibliography you guys may have for this is welcomed.
Hello,
To my understanding, cross-polarization (i.e. VH and HV) has much lower intensity and is influenced more by background and instrument noise than co-polarization. Many ocean applications for ocean phenomena uses co-pol rather than cross-pol, such as oil spill detection and wake detection.
Some book suggestions:
- Introduction to microwave remote sensing (Woodhouse, 2006) → about SAR
- Measuring the Oceans from Space (Robinson, 2004) → the first part gives brief introduction to different remote sensors for ocean application and the second part explains how different ocean phenomena being observed
- Discovering the Ocean from Space (Robinson, 2010) → more detailed explanation on different ocean phenomena
In addition, I would recommend publications from W. Alpers for SAR signatures of different oceanic phenomena.
Cheers!