alternative wet flag for nans

spicy_snow/processing/wet_snow.py

@@ -41,6 +41,9 @@ def id_newly_wet_snow(dataset: xr.Dataset, wet_thresh: int = -2, inplace: bool =
     # identify possible newly wet snow in regions FCF > 0.5 with deltaVV
     dataset['wet_flag'] = dataset['wet_flag'].where(((dataset['fcf'] < 0.5) | (dataset['deltaVV'] > wet_thresh)), 1)
 
+    # mask nans from Sentinel-1 data
+    dataset['wet_flag'] = dataset['wet_flag'].where(~dataset['deltaVV'].isnull())
+
     if not inplace:
         return dataset
 
@@ -73,6 +76,9 @@ def id_newly_frozen_snow(dataset: xr.Dataset, freeze_thresh: int = 2, inplace: b
     # identify possible re-freezing by increases of deltaGammaNaught of 2dB
     dataset['freeze_flag'] = dataset['freeze_flag'].where(dataset['deltaGamma'] < freeze_thresh, 1)
 
+    # mask nans from Sentinel-1 data
+    dataset['freeze_flag'] = dataset['freeze_flag'].where(~dataset['deltaVV'].isnull())
+
     if not inplace:
         return dataset
 
@@ -105,6 +111,9 @@ def id_wet_negative_si(dataset: xr.Dataset, wet_SI_thresh = 0, inplace: bool = F
     # identify wetting of snow by negative snow index with snow present
     dataset['alt_wet_flag'] = dataset['alt_wet_flag'].where(((dataset['ims'] != 4) | (dataset['snow_index'] > wet_SI_thresh)), 1)
 
+    # mask nans from Sentinel-1 data
+    dataset['alt_wet_flag'] = dataset['alt_wet_flag'].where(~dataset['deltaVV'].isnull())
+
     if not inplace:
         return dataset