diff --git a/src/compo/viirs_aod2ioda.py b/src/compo/viirs_aod2ioda.py
index 118496ca8..bec5d4e73 100644
--- a/src/compo/viirs_aod2ioda.py
+++ b/src/compo/viirs_aod2ioda.py
@@ -31,7 +31,7 @@
 
 
 obsvars = {
-    'A': "aerosol_optical_depth_4",
+    'A': "aerosol_optical_depth",
 }
 
 AttrData = {
@@ -44,7 +44,7 @@
 }
 
 VarDims = {
-    'aerosol_optical_depth_4': ['nlocs']
+    'aerosol_optical_depth': ['nlocs', 'nchans'],
 }
 
 
@@ -159,7 +159,7 @@ def _read(self):
             first = False
 
         DimDict['nlocs'] = len(self.outdata[('latitude', 'MetaData')])
-        AttrData['nlocs'] = np.int32(DimDict['nlocs'])
+        DimDict['nchans'] = np.array([4])
 
 
 def main():
diff --git a/test/testoutput/viirs_aod.nc b/test/testoutput/viirs_aod.nc
index 2b2fd6dd1..dd0e32a05 100644
--- a/test/testoutput/viirs_aod.nc
+++ b/test/testoutput/viirs_aod.nc
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:fa00825d74134179e33155b2b6abd800636539462c9ae58b456afce652abcdb7
-size 15597
+oid sha256:08baff6fb016ecffc7b7471cb8caffa39ed8be9bc84b1ceb71245be6ecffa9f2
+size 14480