subroutine testconservmass2d(ngrid,surfmass)

      use comgeomfi_h          
      implicit none

!==================================================================
!     Purpose
!     -------
!     Test conservation of n2 mass 
!  
!     Inputs
!     ------ 
!     ngrid                 Number of vertical columns
!     nlayer                Number of layers
!     pplev(ngrid,nlayer+1) Pressure levels 
!     surfmass    
!
!     Authors
!     ------- 
!     Tanguy Bertrand 2015
!     
!==================================================================

#include "dimensions.h"
#include "dimphys.h"
#include "comcstfi.h"
#include "surfdat.h"
#include "comvert.h"
#include "callkeys.h"
#include "tracer.h"

!-----------------------------------------------------------------------
!     Arguments

      INTEGER ngrid
      REAL surfmass(ngrid)

      ! LOCAL VARIABLES
      INTEGER ig,iq

      ! OUTPUT
      REAL surfmasstot
!-----------------------------------------------------------------------


      surfmasstot=0.0

      do ig = 1, ngrid

         surfmasstot= surfmasstot + surfmass(ig)*area(ig)

       enddo
               
      surfmasstot = surfmasstot/totarea

!      print*,'-------------------------------------------'
      print*,'Total mass surface : ',surfmasstot,' kg m-2'

      end subroutine testconservmass2d