Index: /issm/trunk-jpl/src/m/classes/mask.m
===================================================================
--- /issm/trunk-jpl/src/m/classes/mask.m	(revision 17259)
+++ /issm/trunk-jpl/src/m/classes/mask.m	(revision 17260)
@@ -8,4 +8,16 @@
 		groundedice_levelset = NaN;
 		ice_levelset         = NaN;
+	end
+	methods (Static)
+		function obj = loadobj(obj) % {{{
+			% This function is directly called by matlab when a model object is
+			% loaded. Update old properties here
+
+			%2014 February 5th
+			if numel(obj.ice_levelset)>1 & all(obj.ice_levelset>=0),
+				disp('WARNING: md.mask.ice_levelset>=0, you probably need to change the sign of this levelset');
+			end
+
+		end% }}}
 	end
 	methods