diff --git a/climetlab/core/__init__.py b/climetlab/core/__init__.py
index 347b0d2d..a033504b 100644
--- a/climetlab/core/__init__.py
+++ b/climetlab/core/__init__.py
@@ -137,7 +137,7 @@ def cube(self, *args, **kwargs):
     def get_metadata(self, i):
         return self[i].metadata()
 
-    def unique_values(self, *coords, remapping=None, patches=None, progress_bar=True):
+    def unique_values(self, *coords, remapping=None, patches=None, progress_bar=False):
         """
         Given a list of metadata attributes, such as date, param, levels,
         returns the list of unique values for each attributes
@@ -166,7 +166,7 @@ def unique_values(self, *coords, remapping=None, patches=None, progress_bar=True
 
         return dic
 
-    def combinations(self, *coords, progress_bar=True):
+    def combinations(self, *coords, progress_bar=False):
         assert all(isinstance(k, str) for k in coords), coords
 
         iterable = self