Optimize pressure-level-extrapolation coarsening for physics diagnost…

…ics (#378)

We do not need to compute the blending weights under this coarsening strategy.
This should not change answers, but should make things slightly more
efficient.

FV3/io/FV3GFS_io.F90

@@ -3018,7 +3018,8 @@ subroutine send_diag_manager_controlled_diagnostic_data(Time, Diag, Atm_block, I
         allocate(masked_area(nx, ny, levs))
         extrapolate = trim(coarsening_strategy) .eq. PRESSURE_LEVEL_EXTRAPOLATE
         call get_area(Atm_block, IPD_Data, nx, ny, area)
-        if (trim(coarsening_strategy) .eq. PRESSURE_LEVEL) then
+        if (trim(coarsening_strategy) .eq. PRESSURE_LEVEL .or. &
+            trim(coarsening_strategy) .eq. PRESSURE_LEVEL_EXTRAPOLATE) then
           call vertical_remapping_requirements(delp, area, ptop, phalf, phalf_coarse_on_fine)
         else
           call get_coarse_array_bounds(is_coarse, ie_coarse, js_coarse, je_coarse)
@@ -3168,7 +3169,8 @@ subroutine fv3gfs_diag_output(time, diag, atm_block, IPD_Data, nx, ny, levs, ntc
           allocate(masked_area(nx, ny, levs))
           extrapolate = trim(coarsening_strategy) .eq. PRESSURE_LEVEL_EXTRAPOLATE
           call get_area(Atm_block, IPD_Data, nx, ny, area)
-          if (trim(coarsening_strategy) .eq. PRESSURE_LEVEL) then
+          if (trim(coarsening_strategy) .eq. PRESSURE_LEVEL .or. &
+              trim(coarsening_strategy) .eq. PRESSURE_LEVEL_EXTRAPOLATE) then
             call vertical_remapping_requirements(delp, area, ptop, phalf, phalf_coarse_on_fine)
           else
             call get_coarse_array_bounds(is_coarse, ie_coarse, js_coarse, je_coarse)