diff --git a/parm/aero/berror/aero_diagb.yaml.j2 b/parm/aero/berror/aero_diagb.yaml.j2
index 31cf00b34..a2b0ea95f 100644
--- a/parm/aero/berror/aero_diagb.yaml.j2
+++ b/parm/aero/berror/aero_diagb.yaml.j2
@@ -76,7 +76,26 @@ variables:
   - mass_fraction_of_sea_salt003_in_air
   - mass_fraction_of_sea_salt004_in_air
 
-rescale: {{ aero_diagb_rescale }}    # rescales the filtered std. dev. by "rescale"
+global rescale: 
+  geometry:
+    fms initialization:
+      namelist filename: ./fv3jedi/fmsmpp.nml
+      field table filename: ./fv3jedi/field_table
+    akbk: ./fv3jedi/akbk.nc4
+    layout: 
+    - {{ layout_x }} 
+    - {{ layout_y }}
+    nxp: {{ npx_rescale }}
+    npy: {{ npy_rescale }}
+    npz: {{ npz_ges }}
+    field metadata override: ./fv3jedi/fv3jedi_fieldmetadata_restart.yaml
+  rescale stddev:
+    filetype: fms restart
+    skip coupler file: true
+    dateapath: ./stddev
+    filename_trcr: rescale.fv_tracer.res.nc
+    filename_cplr: rescale.coupler.res 
+
 number of halo points: {{ aero_diagb_n_halo }}
 number of neighbors: {{ aero_diagb_n_neighbors }}
 simple smoothing:
diff --git a/utils/chem/chem_diagb.h b/utils/chem/chem_diagb.h
index 703d4841f..10fc6b5fe 100644
--- a/utils/chem/chem_diagb.h
+++ b/utils/chem/chem_diagb.h
@@ -230,13 +230,27 @@ namespace gdasapp {
         }
       }
 
-      // Rescale
-      if (fullConfig.has("rescale")) {
-        double rescale;
-        fullConfig.get("rescale", rescale);
-        util::multiplyFieldSet(bkgErrFs, rescale);
+     // Rescale
+      if (fullConfig.has("global rescale")) {
+        const eckit::LocalConfiguration GlobalRescaleConfig(fullConfig, "global rescale");
+        const eckit::LocalConfiguration GlobalRescaleGeomConfig(GlobalRescaleConfig, "geometry");
+        const fv3jedi::Geometry GlobalRescaleGeom(GlobalRescaleGeomConfig, this-> getComm());
+        fv3jedi::Increment global_rescale(GlobalRescaleGeom, chemVars, cycleDate);
+        global_rescale.zero();
+        const eckit::LocalConfiguration GlobalRescaleStdConfig(GlobalRescaleConfig,
+                                                    "rescale stddev");
+        global_rescale.read(GlobalRescaleStdConfig);
+        // interpolate to background resolution
+        fv3jedi::Increment global_rescale_interp(geom, global_rescale);
+        atlas::FieldSet xrsFs;
+        global_rescale_interp.toFieldSet(xrsFs);
+        oops::Log::info() << "global rescaling coefficients:" << std::endl;
+        oops::Log::info() << xrsFs << std::endl;
+        util::multiplyFieldSets(bkgErrFs, xrsFs);
       }
 
+
+
       bkgErr.fromFieldSet(bkgErrFs);
 
       // Hybrid B option
@@ -274,6 +288,7 @@ namespace gdasapp {
         double rescale_staticb;
         ClimBConfig.get("staticb rescaling factor", rescale_staticb);
 
+
         // Combine diagb and climatological background errors
         fv3jedi::Increment stddev_hybrid(geom, chemVars, cycleDate);
         stddev_hybrid.zero();