diff --git a/calc_ref_state.py b/calc_ref_state.py
index 974eba7..b0a60d5 100644
--- a/calc_ref_state.py
+++ b/calc_ref_state.py
@@ -20,16 +20,23 @@ from get_data import get_data_woa2009 as read_data
 # MANUAL DEFINED OUTPUTS MISSING
 # ############################################################################################
 print 'MANUAL DEFINED OUTPUTS MISSING'
+dim       = ('lon','lat','z','time',)
 dir_plot  = '/glusterfs/inspect/users/xg911182/Code/Python/plots_test/'
 variables = {'s':{},'theta':{},'grd':[],'valid':[]}
 
 # Input 1 ####################################################################################
 # Physical constants
-# output        : r_earth
+# output        : r_earth, rho0, grav, gbuo
 #     r_earth   : earth radis           [m]
+#     rho0      : reference density     [kg m**-3]
+#     grav      : gravity               [m s**-2]
+#     gbuo      : 
 # PHYSICAL CONSTATS MISSING
 # ############################################################################################
-print 'PHYSICAL CONSTATS MISSING'
+r_earth = 6.4e06
+rho0    = 1027.0
+grav    = 9.81
+gbuo    = -grav/rho0
 
 # step a #####################################################################################
 # Read necessary data to calculate reference state
@@ -46,7 +53,7 @@ beg_time = time.time()
 print ''
 print ' ----------------------------------------------'
 print ' Read data'
-grd, data = read_data(variables)
+grd, data = read_data(variables,dim)
 print ' ----------------------------------------------'
 end_time = time.time()
 print 'Elapsed time to read data:         '+ '{:.2f}'.format(end_time-beg_time)+'s'