diff --git a/modules/aeolus/aeolus_amv.py b/modules/aeolus/aeolus_amv.py
index acc7bfc5e41901cd5b4d1f4677c4e0e61524e656..9824fdc6e54282683683760887e840af1039e4d5 100644
--- a/modules/aeolus/aeolus_amv.py
+++ b/modules/aeolus/aeolus_amv.py
@@ -1781,7 +1781,7 @@ def match_calipso_clavrx_to_amvs(calipso_clavrx_path, calipso_clavrx_file, amv_f
     ys = calipso_clavrx_nc4['y'][:]
     clvr_xy_s = zip(xs, ys)
 
-    for clvr_xy in clvr_xy_s:
+    for idx, clvr_xy in enumerate(clvr_xy_s):
         cc, ll = clvr_xy
 
         c_rng, l_rng = get_search_box(cc, ll)