!--------------------------------------------------------------------------
   !---------------------------- pvort_only ----------------------------------
   !$OMP DO SCHEDULE(STATIC)
   DO ij = 1, dual_num
      DO l = 1, llm
         etav = 0.d0
         DO iedge = 1, dual_deg(ij)
            edge = dual_edge(iedge,ij)
            etav = etav + dual_ne(iedge,ij)*u(l,edge)
         END DO
         hv=0.
         DO ivertex = 1, dual_deg(ij)
            vertex = dual_vertex(ivertex,ij)
            hv = hv + Riv2(ivertex,ij)*rhodz(l,vertex)
         END DO
         qv(l,ij) = (etav + fv(ij)*Av(ij) )/(hv*Av(ij))
      END DO
   END DO
   !$OMP END DO
   !$OMP DO SCHEDULE(STATIC)
   DO edge = 1, edge_num
      ij_up = up(edge)
      ij_down = down(edge)
      DO l = 1, llm
         qu(l,edge)=0.5d0*(qv(l,ij_down)+qv(l,ij_up))
      END DO
   END DO
   !$OMP END DO
   !---------------------------- pvort_only ----------------------------------
   !--------------------------------------------------------------------------