Wind Effects on SAR water threshold

It is true that higher wind speeds at the time of SAR data acquisition increase the water backscatter. But just wondering to what extent the “wind direction” can be effective in water roughness.

I haven’t found a strong correlation (for a large dataset, Asce pass) between wind speed/wind direction and water backscatter (in db unit).

In some cases, in the summer time while the wind speed was low , the water backscatter was high and speckled water bodies as the result.

Any comment is appreciated.