diff --git a/config_src/external/drifters/MOM_particles.F90 b/config_src/external/drifters/MOM_particles.F90
index aad918e5a4..fa3840c6c2 100644
--- a/config_src/external/drifters/MOM_particles.F90
+++ b/config_src/external/drifters/MOM_particles.F90
@@ -11,19 +11,20 @@ module MOM_particles_mod
 implicit none ; private
 
 public particles, particles_run, particles_init, particles_save_restart, particles_end
+public particles_to_k_space, particles_to_z_space
 
 contains
 
 !> Initializes particles container "parts"
-subroutine particles_init(parts, Grid, Time, dt, u, v)
+subroutine particles_init(parts, Grid, Time, dt, u, v, h)
   ! Arguments
   type(particles), pointer, intent(out) :: parts !< Container for all types and memory
   type(ocean_grid_type), target, intent(in) :: Grid !< Grid type from parent model
   type(time_type), intent(in) :: Time !< Time type from parent model
-  real, intent(in)            :: dt   !< particle timestep [s]
-  real, dimension(:,:,:), intent(in)    :: u !< Zonal velocity field [m s-1]
-  real, dimension(:,:,:), intent(in)    :: v !< Meridional velocity field [m s-1]
-
+  real, intent(in)            :: dt !< particle timestep in seconds [T ~> s]
+  real, dimension(:,:,:),intent(in)      :: u !< Zonal velocity field [L T-1 ~> m s-1]
+  real, dimension(:,:,:),intent(in)      :: v !< Meridional velocity field [L T-1 ~> m s-1]
+  real, dimension(:,:,:),intent(in)      :: h !< Thickness of each layer [H ~> m or kg m-2]
 end subroutine particles_init
 
 !> The main driver the steps updates particles
@@ -31,8 +32,8 @@ subroutine particles_run(parts, time, uo, vo, ho, tv, stagger)
   ! Arguments
   type(particles), pointer :: parts !< Container for all types and memory
   type(time_type), intent(in) :: time !< Model time
-  real, dimension(:,:,:), intent(in) :: uo !< Ocean zonal velocity [m s-1]
-  real, dimension(:,:,:), intent(in) :: vo !< Ocean meridional velocity [m s-1]
+  real, dimension(:,:,:), intent(in) :: uo !< Ocean zonal velocity [L T-1 ~>m s-1]
+  real, dimension(:,:,:), intent(in) :: vo !< Ocean meridional velocity [L T-1~> m s-1]
   real, dimension(:,:,:), intent(in) :: ho !< Ocean layer thickness [H ~> m or kg m-2]
   type(thermo_var_ptrs),  intent(in) :: tv !< structure containing pointers to available thermodynamic fields
   integer, optional, intent(in) :: stagger !< Flag for whether velocities are staggered
@@ -41,21 +42,38 @@ end subroutine particles_run
 
 
 !>Save particle locations (and sometimes other vars) to restart file
-subroutine particles_save_restart(parts, temp, salt)
+subroutine particles_save_restart(parts, h, temp, salt)
   ! Arguments
   type(particles), pointer :: parts !< Container for all types and memory
-  real, dimension(:,:,:), optional, intent(in) :: temp !< Optional container for temperature
-  real, dimension(:,:,:), optional, intent(in) :: salt !< Optional container for salinity
+  real, dimension(:,:,:),intent(in)      :: h !< Thickness of each layer [H ~> m or kg m-2]
+  real, dimension(:,:,:), optional, intent(in) :: temp !< Optional container for temperature [C ~> degC]
+  real, dimension(:,:,:), optional, intent(in) :: salt !< Optional container for salinity [S ~> ppt]
 
 end subroutine particles_save_restart
 
 !> Deallocate all memory and disassociated pointer
-subroutine particles_end(parts, temp, salt)
+subroutine particles_end(parts, h, temp, salt)
   ! Arguments
   type(particles), pointer :: parts !< Container for all types and memory
-  real, dimension(:,:,:), optional, intent(in) :: temp !< Optional container for temperature
-  real, dimension(:,:,:), optional, intent(in) :: salt !< Optional container for salinity
+  real, dimension(:,:,:),intent(in)      :: h !< Thickness of each layer [H ~> m or kg m-2]
+  real, dimension(:,:,:), optional, intent(in) :: temp !< Optional container for temperature [C ~> degC]
+  real, dimension(:,:,:), optional, intent(in) :: salt !< Optional container for salinity [S ~> ppt]
 
 end subroutine particles_end
 
+subroutine particles_to_k_space(parts, h)
+  ! Arguments
+  type(particles), pointer :: parts !< Container for all types and memory
+  real, dimension(:,:,:),intent(in)      :: h !< Thickness of layers [H ~> m or kg m-2]
+
+end subroutine particles_to_k_space
+
+
+subroutine particles_to_z_space(parts, h)
+  ! Arguments
+  type(particles), pointer :: parts !< Container for all types and memory
+  real, dimension(:,:,:),intent(in)      :: h !< Thickness of layers [H ~> m or kg m-2]
+
+end subroutine particles_to_z_space
+
 end module MOM_particles_mod
diff --git a/src/core/MOM.F90 b/src/core/MOM.F90
index df3a308e85..d2df26524d 100644
--- a/src/core/MOM.F90
+++ b/src/core/MOM.F90
@@ -162,7 +162,7 @@ module MOM
 use MOM_offline_main,          only : offline_advection_layer, offline_transport_end
 use MOM_ice_shelf,             only : ice_shelf_CS, ice_shelf_query, initialize_ice_shelf
 use MOM_particles_mod,         only : particles, particles_init, particles_run, particles_save_restart, particles_end
-
+use MOM_particles_mod,         only : particles_to_k_space, particles_to_z_space
 implicit none ; private
 
 #include <MOM_memory.h>
@@ -1541,6 +1541,10 @@ subroutine step_MOM_thermo(CS, G, GV, US, u, v, h, tv, fluxes, dtdia, &
 
       call preAle_tracer_diagnostics(CS%tracer_Reg, G, GV)
 
+      if (CS%use_particles) then
+        call particles_to_z_space(CS%particles, h)
+      endif
+
       if (CS%debug) then
         call MOM_state_chksum("Pre-ALE ", u, v, h, CS%uh, CS%vh, G, GV, US, omit_corners=.true.)
         call hchksum(tv%T,"Pre-ALE T", G%HI, haloshift=1, omit_corners=.true., scale=US%C_to_degC)
@@ -1588,6 +1592,11 @@ subroutine step_MOM_thermo(CS, G, GV, US, u, v, h, tv, fluxes, dtdia, &
       call cpu_clock_end(id_clock_ALE)
     endif   ! endif for the block "if ( CS%use_ALE_algorithm )"
 
+
+    if (CS%use_particles) then
+      call particles_to_k_space(CS%particles, h)
+    endif
+
     dynamics_stencil = min(3, G%Domain%nihalo, G%Domain%njhalo)
     call create_group_pass(pass_uv_T_S_h, u, v, G%Domain, halo=dynamics_stencil)
     if (associated(tv%T)) &
@@ -3232,7 +3241,7 @@ subroutine finish_MOM_initialization(Time, dirs, CS, restart_CSp)
   G => CS%G ; GV => CS%GV ; US => CS%US
 
   if (CS%use_particles) then
-    call particles_init(CS%particles, G, CS%Time, CS%dt_therm, CS%u, CS%v)
+    call particles_init(CS%particles, G, CS%Time, CS%dt_therm, CS%u, CS%v, CS%h)
   endif
 
   ! Write initial conditions
@@ -3935,7 +3944,7 @@ subroutine save_MOM6_internal_state(CS, dirs, time, stamp_time)
 
     ! Could call save_restart(CS%restart_CSp) here
 
-    if (CS%use_particles) call particles_save_restart(CS%particles)
+    if (CS%use_particles) call particles_save_restart(CS%particles, CS%h)
 
 end subroutine save_MOM6_internal_state
 
@@ -3978,7 +3987,7 @@ subroutine MOM_end(CS)
   endif
 
   if (CS%use_particles) then
-    call particles_end(CS%particles)
+    call particles_end(CS%particles, CS%h)
     deallocate(CS%particles)
   endif