diff --git a/opendrift/models/basemodel/environment.py b/opendrift/models/basemodel/environment.py
index 7eb0fb04b..2240bc32d 100644
--- a/opendrift/models/basemodel/environment.py
+++ b/opendrift/models/basemodel/environment.py
@@ -933,7 +933,7 @@ def get_environment(self, variables, time, lon, lat, z, profiles=None, profiles_
 
         return env.view(np.recarray), env_profiles, missing
 
-    def get_variables_along_trajectory(self, variables, lons, lats, times):
+    def get_variables_along_trajectory(self, variables, lons, lats, times, z=0):
         self.finalize()
         data = {'time': times, 'lon': lons, 'lat': lats}
         for var in variables:
@@ -942,7 +942,7 @@ def get_variables_along_trajectory(self, variables, lons, lats, times):
             self.time = time
             d = self.get_environment(lon=np.atleast_1d(lons[i]),
                                      lat=np.atleast_1d(lats[i]),
-                                     z=np.atleast_1d(0),
+                                     z=np.atleast_1d(z),
                                      time=time,
                                      variables=variables,
                                      profiles=None)