Hi,
I assume that your research area is over land and not sea ice. If that’s the case then you can use two different methods to detect snow:
- Based on backscatter intensity of snow
- InSAR and coherence analysis
In snow free areas we would expect a higher backscatter intensity compared to areas covered in snow (interaction of microwaves with snow is complicated and can produce higher backscatter signal in some cases)
You can also derive a coherence map where snow free areas will have higher coherence due to more stable scatterers.
For more details, look at this paper