diff --git a/CONTRIBUTORS.md b/CONTRIBUTORS.md
index 24b412e65..4bf499474 100644
--- a/CONTRIBUTORS.md
+++ b/CONTRIBUTORS.md
@@ -11,4 +11,5 @@
 | DrTVockerodtMO  | Terence Vockerodt | Met Office  | 2026-01-08 |
 | MetBenjaminWent | Benjamin Went     | Met Office  | 2026-01-15 |
 | timgraham-Met   | Tim Graham        | Met Office  | 2026-01-15 |
-| mo-alistairp    | Alistair Pirrie   | Met Office  | 2026-01-19 |
\ No newline at end of file
+| mcdalvi         | Mohit Dalvi       | Met Office  | 2026-01-15 |
+| mo-alistairp    | Alistair Pirrie   | Met Office  | 2026-01-19 |
diff --git a/interfaces/physics_schemes_interface/source/legacy/ukca_interface/ukca_volcanic_so2.F90 b/interfaces/physics_schemes_interface/source/legacy/ukca_interface/ukca_volcanic_so2.F90
index 05f319418..da5d22651 100644
--- a/interfaces/physics_schemes_interface/source/legacy/ukca_interface/ukca_volcanic_so2.F90
+++ b/interfaces/physics_schemes_interface/source/legacy/ukca_interface/ukca_volcanic_so2.F90
@@ -150,6 +150,19 @@ subroutine ukca_volcanic_so2                                                   &
 
 if (lhook) call dr_hook(ModuleName//':'//RoutineName,zhook_in,zhook_handle)
 
+! Functionality is not currently implemented in LFRic.
+errcode = 1
+cmessage = 'Volcanic SO2 emissions not yet implemented.' //                    &
+           'Logical l_ukca_so2ems_expvolc should be set to .false.'
+call ereport(RoutineName, errcode, cmessage)
+
+! Allocate true_latitude, true_longitude arrays and initialise temporarily.
+! These should be subsequently populated from LFRic w3 fields.
+if ( .not. allocated(true_latitude)) allocate(true_latitude(row_length,rows))
+if ( .not. allocated(true_longitude)) allocate(true_longitude(row_length,rows))
+true_latitude(:,:) = 0.0
+true_longitude(:,:) = 0.0
+
 ! On first call, determine locations on the UM grid where volcanos are located.
 ! The method assumes that the grid is a regular latitude-longitude grid with
 ! latitude constant on each row and equally-spaced between rows and
@@ -334,6 +347,7 @@ subroutine ukca_volcanic_so2                                                   &
         l2 = l2 - 1
       end do
       if (l2 < l1) l1 = l2
+      allocate(weight_volc_vertdist(l2-l1+1))
       ! express emission as increase in average increase in mass mixing ratio
       weight_volc_vertdist = (abs(r_theta_levels(i,j,l1+1:l2+1) -              &
                              r_theta_levels(i,j,l1-1:l2-1))/2) *               &
@@ -343,10 +357,14 @@ subroutine ukca_volcanic_so2                                                   &
       so2_mmr(i,j,l1:l2) = so2_mmr(i,j,l1:l2) + emission(k) *                  &
                            (weight_volc_vertdist/sum(weight_volc_vertdist)) /  &
                            mass(i,j,l1:l2)
+      deallocate(weight_volc_vertdist)
     end if
   end if
 end do
 
+if (allocated(true_latitude)) deallocate(true_latitude)
+if (allocated(true_longitude)) deallocate(true_longitude)
+
 if (lhook) call dr_hook(ModuleName//':'//RoutineName,zhook_out,zhook_handle)
 return
 end subroutine ukca_volcanic_so2