diff --git a/tests/test_qartod.py b/tests/test_qartod.py
index d3f25b9..858d6e4 100644
--- a/tests/test_qartod.py
+++ b/tests/test_qartod.py
@@ -33,7 +33,7 @@ def test_location(self):
         Ensure that longitudes and latitudes are within reasonable bounds.
         """
         lon = [  80.0, -78.5, 500.500]
-        lat = [np.NaN,  50.0,   -60.0]
+        lat = [np.nan,  50.0,   -60.0]
 
         npt.assert_array_equal(
             qartod.location_test(lon=lon, lat=lat),