@Andiray You may try Vegetation Condition Index as a proxy for SM.
The global product is here - https://land.copernicus.eu/global/products/vci
First you need a shapefile with numerical values (hoehe_cm in my case)
Load it into SNAP and overlay it with your SAR data
Then open the correlative plot view 
Select the point shapefile and the attribute and correlate the raster values with the point information
1 Like
Hi @ABraun, how to make this shapefile? I only have ground data but I don’t know how to make it to shapefile.
I have coordinate point and value of soil moisture in ground data. I’m so sorry. I don’t have basic in SNAP
Thanks
SNAP can import csv files when they are formatted correctly.
If not, load the coordinates (and moisture attribute) in a GIS and export it as a shapefile. There are lots of tutorials on this around.
Import of CSV files into QGIS: https://www.qgistutorials.com/en/docs/importing_spreadsheets_csv.html
Import of CSV files into SNAP: Import CSV File
I have correlative plot now.
whether this graph is true to soil moisture validation?
My step backscatter is:
- Multilooking (4:1)
- Calibration: Sigma 0
- Speckle Filter : Gamma Map
- Terrain Correction
Does it only at this step? Shouldn’t I find its polarimetric decomposition?
Regards
R²=0.17 means that you can currently only explain 17% of the variations of both variables by the each other. For statistically valid predictions you need probably more measurements and higher R² (0.5 and above).
If you have the chance for polarimetric decomposition, you can correlate the moisture with new rasters and see if their predictive value is higher. But Sentinel-1 is dual-pol only.
What kind of new raster can i use sir?
Can’t I use sentinel 1 _SLC for calculate Polarimetric Decompotion?
Apply Orbit file>>Calibrate>>Tops Deburst>>H/A dual deccomposition.
yes, this is probably the only one which works for Sentinel-1. Then you can correlate each band with the moisture. I would also try VH as well.
When I do step Apply Orbit File, why in https://qc.sentinel1.eo.esa.int/ is not provide update POEORB?
what do you mean?
I want use S1A_SLC on date: 10/05.2019 but when Apply Orbit File is error.
So I download manual in https://qc.sentinel1.eo.esa.int/, but its not provided for this time.
precise orbits are provided about three weeks after the image acquisition.
Hi, I am really don’t understand to used GRD Product.
I using step: >>Multilooking >> Calibrate to Sigma0 >> Speckle Filter : Gamma Map >> Terrain Correction
But the intensity is contains many noise. What is the best step to find backscatter?
Regards
Multi-looking is not needed because GRD data is already range-detected.
If you don’t need the comparably high spatial resolution of 10 meters, you can still multi-look your data to downsample it a lower spatial resolution (e.g. 60 meters) with to enhance your image quality.
If you need 10 m of spatial resolution, the best choice to reduce speckle is to test and compare different filter types.
Thanks you Sir, I think multilooking is similar with Thermal Noise Removal. I will do this step:
But in thermal noise removal is error. And I really don’t know to fix this.
Are you have simple solution to fix this Sir?
Are you sure that all updates are installed? Check under Menu > Help > Check For Updates.
How about this sir?