diff --git a/changelog/473.feature.md b/changelog/473.feature.md
new file mode 100644
index 000000000..23b2982f8
--- /dev/null
+++ b/changelog/473.feature.md
@@ -0,0 +1 @@
+Added ESMValTool ozone diagnostics.
diff --git a/packages/climate-ref-core/src/climate_ref_core/data/cmip6_cmip7_variable_map.json b/packages/climate-ref-core/src/climate_ref_core/data/cmip6_cmip7_variable_map.json
index bd179da7f..b465080c2 100644
--- a/packages/climate-ref-core/src/climate_ref_core/data/cmip6_cmip7_variable_map.json
+++ b/packages/climate-ref-core/src/climate_ref_core/data/cmip6_cmip7_variable_map.json
@@ -5,6 +5,36 @@
   "description": "CMIP6-to-CMIP7 variable mappings extracted from the CMIP7 Data Request. Filtered to mon/fx tables and variables used by REF providers. Keyed by CMIP6 compound name (table_id.variable_id). Regenerate with: uv run python scripts/extract-data-request-mappings.py "
  },
  "variables": {
+  "AERmon.o3": {
+   "table_id": "AERmon",
+   "variable_id": "o3",
+   "cmip6_compound_name": "AERmon.o3",
+   "cmip7_compound_name": "atmosChem.o3.tavg-al-hxy-u.mon.glb",
+   "branded_variable": "o3_tavg-al-hxy-u",
+   "branding_suffix": "tavg-al-hxy-u",
+   "temporal_label": "tavg",
+   "vertical_label": "al",
+   "horizontal_label": "hxy",
+   "area_label": "u",
+   "realm": "atmosChem",
+   "region": "glb",
+   "frequency": "mon"
+  },
+  "AERmon.o3inst": {
+   "table_id": "AERmon",
+   "variable_id": "o3",
+   "cmip6_compound_name": "AERmon.o3inst",
+   "cmip7_compound_name": "atmosChem.o3.tpt-al-hxy-u.mon.glb",
+   "branded_variable": "o3_tpt-al-hxy-u",
+   "branding_suffix": "tpt-al-hxy-u",
+   "temporal_label": "tpt",
+   "vertical_label": "al",
+   "horizontal_label": "hxy",
+   "area_label": "u",
+   "realm": "atmosChem aerosol",
+   "region": "glb",
+   "frequency": "mon"
+  },
   "AERmon.toz": {
    "table_id": "AERmon",
    "variable_id": "toz",
@@ -65,6 +95,21 @@
    "region": "glb",
    "frequency": "mon"
   },
+  "AERmonZ.o3": {
+   "table_id": "AERmonZ",
+   "variable_id": "o3",
+   "cmip6_compound_name": "AERmonZ.o3",
+   "cmip7_compound_name": "atmosChem.o3.tavg-p39-hy-air.mon.glb",
+   "branded_variable": "o3_tavg-p39-hy-air",
+   "branding_suffix": "tavg-p39-hy-air",
+   "temporal_label": "tavg",
+   "vertical_label": "p39",
+   "horizontal_label": "hy",
+   "area_label": "air",
+   "realm": "atmosChem",
+   "region": "glb",
+   "frequency": "mon"
+  },
   "AERmonZ.ta": {
    "table_id": "AERmonZ",
    "variable_id": "ta",
@@ -395,6 +440,36 @@
    "region": "30S-90S",
    "frequency": "mon"
   },
+  "Amon.o3": {
+   "table_id": "Amon",
+   "variable_id": "o3",
+   "cmip6_compound_name": "Amon.o3",
+   "cmip7_compound_name": "atmosChem.o3.tavg-p19-hxy-air.mon.glb",
+   "branded_variable": "o3_tavg-p19-hxy-air",
+   "branding_suffix": "tavg-p19-hxy-air",
+   "temporal_label": "tavg",
+   "vertical_label": "p19",
+   "horizontal_label": "hxy",
+   "area_label": "air",
+   "realm": "atmosChem",
+   "region": "glb",
+   "frequency": "mon"
+  },
+  "Amon.o3Clim": {
+   "table_id": "Amon",
+   "variable_id": "o3",
+   "cmip6_compound_name": "Amon.o3Clim",
+   "cmip7_compound_name": "atmosChem.o3.tclm-p19-hxy-air.mon.glb",
+   "branded_variable": "o3_tclm-p19-hxy-air",
+   "branding_suffix": "tclm-p19-hxy-air",
+   "temporal_label": "tclm",
+   "vertical_label": "p19",
+   "horizontal_label": "hxy",
+   "area_label": "air",
+   "realm": "atmosChem",
+   "region": "glb",
+   "frequency": "mon"
+  },
   "Amon.pr": {
    "table_id": "Amon",
    "variable_id": "pr",
diff --git a/packages/climate-ref-core/src/climate_ref_core/esgf/obs4mips.py b/packages/climate-ref-core/src/climate_ref_core/esgf/obs4mips.py
index fe1609d5f..337d67c61 100644
--- a/packages/climate-ref-core/src/climate_ref_core/esgf/obs4mips.py
+++ b/packages/climate-ref-core/src/climate_ref_core/esgf/obs4mips.py
@@ -71,7 +71,7 @@ def __init__(
             Optional time range filter (start, end) in YYYY-MM format
         """
         self.slug = slug
-        self.facets = facets
+        self.facets = {"project": "obs4MIPs", **facets}
         self.remove_ensembles = remove_ensembles
         self.time_span = time_span
 
diff --git a/packages/climate-ref-core/tests/unit/esgf/test_obs4mips.py b/packages/climate-ref-core/tests/unit/esgf/test_obs4mips.py
index 73d84ce8d..98a0700dd 100644
--- a/packages/climate-ref-core/tests/unit/esgf/test_obs4mips.py
+++ b/packages/climate-ref-core/tests/unit/esgf/test_obs4mips.py
@@ -15,7 +15,11 @@ def test_init_basic(self):
             facets={"source_id": "GPCP-SG", "variable_id": "pr"},
         )
         assert request.slug == "test-obs"
-        assert request.facets == {"source_id": "GPCP-SG", "variable_id": "pr"}
+        assert request.facets == {
+            "project": "obs4MIPs",
+            "source_id": "GPCP-SG",
+            "variable_id": "pr",
+        }
         assert request.remove_ensembles is False
         assert request.time_span is None
         assert request.source_type == "obs4MIPs"
diff --git a/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/dataset_registry/data.txt b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/dataset_registry/data.txt
index f1744d279..94ce67251 100644
--- a/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/dataset_registry/data.txt
+++ b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/dataset_registry/data.txt
@@ -80,6 +80,7 @@ ESMValTool/OBS/Tier2/ESACCI-CLOUD/OBS_ESACCI-CLOUD_sat_AVHRR-AMPM-fv3.0_Amon_rlu
 ESMValTool/OBS/Tier2/ESACCI-CLOUD/OBS_ESACCI-CLOUD_sat_AVHRR-AMPM-fv3.0_Amon_rlutcs_198201-201612.nc 21f096ecafff659e5c7e3338060425f7194e5d1b39c9510865496e04ecac3d75
 ESMValTool/OBS/Tier2/ESACCI-CLOUD/OBS_ESACCI-CLOUD_sat_AVHRR-AMPM-fv3.0_Amon_rsut_198201-201612.nc f2c3f3afcdc2e730df7985c210a3de89b0d4f83b150e0c3846f7ac3c5fa9c54a
 ESMValTool/OBS/Tier2/ESACCI-CLOUD/OBS_ESACCI-CLOUD_sat_AVHRR-AMPM-fv3.0_Amon_rsutcs_198201-201612.nc d180d3140d4c1f6b9bb1960e07b45f192643f047e7c272c8c8c7070296ca3ab7
+ESMValTool/OBS/Tier2/ESACCI-OZONE/OBS6_ESACCI-OZONE_sat_L3_AERmon_o3_198410-202212.nc 7ed9446b66e3b8382df4b6ce3074499a9ad00b7173a784c95df289fc9971ce69
 ESMValTool/OBS/Tier2/HadCRUT5/OBS_HadCRUT5_ground_5.0.1.0-analysis_Amon_tas_185001-202112.nc edc3ee50b942dfbeccfd58b574df3393555379c2de3418c9717ac11dbafc12fc
 ESMValTool/OBS/Tier2/ISCCP-FH/OBS_ISCCP-FH_sat_v0_Amon_rlut_198401-201612.nc 650b347df432f6e5f3f693310aad695a7502f2905ac545753c7d4ccb0592adbe
 ESMValTool/OBS/Tier2/ISCCP-FH/OBS_ISCCP-FH_sat_v0_Amon_rlutcs_198401-201612.nc a90d9e035447f8778a2f64362411c079536d9dea559f6d53d032710b2c9b00e3
diff --git a/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/diagnostics/__init__.py b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/diagnostics/__init__.py
index 6ed1dac88..3d88468c6 100644
--- a/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/diagnostics/__init__.py
+++ b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/diagnostics/__init__.py
@@ -13,6 +13,13 @@
 from climate_ref_esmvaltool.diagnostics.ecs import EquilibriumClimateSensitivity
 from climate_ref_esmvaltool.diagnostics.enso import ENSOBasicClimatology, ENSOCharacteristics
 from climate_ref_esmvaltool.diagnostics.example import GlobalMeanTimeseries
+from climate_ref_esmvaltool.diagnostics.ozone import (
+    O3LatMonthMapplot,
+    O3LatTimeMapplot,
+    O3PolarCapTimeseriesNH,
+    O3PolarCapTimeseriesSH,
+    O3ZonalMeanProfiles,
+)
 from climate_ref_esmvaltool.diagnostics.regional_historical_changes import (
     RegionalHistoricalAnnualCycle,
     RegionalHistoricalTimeSeries,
@@ -37,6 +44,11 @@
     "ENSOCharacteristics",
     "EquilibriumClimateSensitivity",
     "GlobalMeanTimeseries",
+    "O3LatMonthMapplot",
+    "O3LatTimeMapplot",
+    "O3PolarCapTimeseriesNH",
+    "O3PolarCapTimeseriesSH",
+    "O3ZonalMeanProfiles",
     "RegionalHistoricalAnnualCycle",
     "RegionalHistoricalTimeSeries",
     "RegionalHistoricalTrend",
diff --git a/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/diagnostics/ozone.py b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/diagnostics/ozone.py
new file mode 100644
index 000000000..bdd239a41
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/diagnostics/ozone.py
@@ -0,0 +1,377 @@
+import pandas
+
+from climate_ref_core.constraints import (
+    AddSupplementaryDataset,
+    PartialDateTime,
+    RequireContiguousTimerange,
+    RequireTimerange,
+)
+from climate_ref_core.datasets import FacetFilter, SourceDatasetType
+from climate_ref_core.diagnostics import DataRequirement
+from climate_ref_core.esgf.cmip6 import CMIP6Request
+from climate_ref_core.esgf.cmip7 import CMIP7Request
+from climate_ref_core.esgf.obs4mips import Obs4MIPsRequest
+from climate_ref_core.testing import TestCase, TestDataSpecification
+from climate_ref_esmvaltool.diagnostics.base import ESMValToolDiagnostic, get_cmip_source_type
+from climate_ref_esmvaltool.recipe import dataframe_to_recipe
+from climate_ref_esmvaltool.types import Recipe
+
+ozone_obs_filter = FacetFilter(
+    facets={
+        "variable_id": "toz",
+        "source_id": "C3S-GTO-ECV-9-0",
+        "frequency": "mon",
+    },
+)
+
+toz_data_requirement = (
+    (
+        DataRequirement(
+            source_type=SourceDatasetType.CMIP6,
+            filters=(
+                FacetFilter(
+                    facets={
+                        "variable_id": "toz",
+                        "experiment_id": "historical",
+                        "table_id": "AERmon",
+                    },
+                ),
+            ),
+            group_by=("source_id", "member_id", "grid_label"),
+            constraints=(
+                RequireTimerange(
+                    group_by=("instance_id",),
+                    start=PartialDateTime(1996, 1),
+                    end=PartialDateTime(2014, 12),
+                ),
+                RequireContiguousTimerange(group_by=("instance_id",)),
+                AddSupplementaryDataset.from_defaults("areacella", SourceDatasetType.CMIP6),
+            ),
+        ),
+        DataRequirement(
+            source_type=SourceDatasetType.obs4MIPs,
+            filters=(ozone_obs_filter,),
+            group_by=("source_id",),
+            constraints=(
+                RequireTimerange(
+                    group_by=("instance_id",),
+                    start=PartialDateTime(1996, 1),
+                    end=PartialDateTime(2014, 12),
+                ),
+            ),
+        ),
+    ),
+    (
+        DataRequirement(
+            source_type=SourceDatasetType.CMIP7,
+            filters=(
+                FacetFilter(
+                    facets={
+                        "variable_id": "toz",
+                        "experiment_id": "historical",
+                        "branded_variable": "toz_tavg-u-hxy-u",
+                        "frequency": "mon",
+                        "region": "glb",
+                    },
+                ),
+            ),
+            group_by=("source_id", "variant_label", "grid_label"),
+            constraints=(
+                RequireTimerange(
+                    group_by=("instance_id",),
+                    start=PartialDateTime(1996, 1),
+                    end=PartialDateTime(2014, 12),
+                ),
+                RequireContiguousTimerange(group_by=("instance_id",)),
+                AddSupplementaryDataset.from_defaults("areacella", SourceDatasetType.CMIP7),
+            ),
+        ),
+        DataRequirement(
+            source_type=SourceDatasetType.obs4MIPs,
+            filters=(ozone_obs_filter,),
+            group_by=("source_id",),
+            constraints=(
+                RequireTimerange(
+                    group_by=("instance_id",),
+                    start=PartialDateTime(1996, 1),
+                    end=PartialDateTime(2014, 12),
+                ),
+            ),
+        ),
+    ),
+)
+toz_test_spec = TestDataSpecification(
+    test_cases=(
+        TestCase(
+            name="cmip6",
+            description="Test with CMIP6 data.",
+            requests=(
+                CMIP6Request(
+                    slug="cmip6",
+                    facets={
+                        "experiment_id": "historical",
+                        "frequency": "mon",
+                        "source_id": "GFDL-ESM4",
+                        "variable_id": "toz",
+                    },
+                    remove_ensembles=True,
+                    time_span=("1996", "2015"),
+                ),
+                Obs4MIPsRequest(
+                    slug="obs4mips",
+                    facets=ozone_obs_filter.facets,
+                    remove_ensembles=False,
+                    time_span=("1980", "2009"),
+                ),
+            ),
+        ),
+        TestCase(
+            name="cmip7",
+            description="Test with CMIP7 data.",
+            requests=(
+                CMIP7Request(
+                    slug="cmip7",
+                    facets={
+                        "experiment_id": ["historical"],
+                        "source_id": "GFDL-ESM4",
+                        "variable_id": "toz",
+                        "branded_variable": [
+                            "toz_tavg-u-hxy-u",
+                        ],
+                        "variant_label": "r1i1p1f1",
+                        "frequency": ["fx", "mon"],
+                        "region": "glb",
+                    },
+                    remove_ensembles=True,
+                    time_span=("1980", "2009"),
+                ),
+                Obs4MIPsRequest(
+                    slug="obs4mips",
+                    facets=ozone_obs_filter.facets,
+                    remove_ensembles=False,
+                    time_span=("1980", "2009"),
+                ),
+            ),
+        ),
+    ),
+)
+
+
+class O3LatTimeMapplot(ESMValToolDiagnostic):
+    """
+    Calculate the ozone diagnostics - zonal mean total column ozone vs. time.
+    """
+
+    name = "Ozone Diagnostics"
+    slug = "ozone-lat-time"
+    base_recipe = "ref/recipe_ref_ozone.yml"
+
+    data_requirements = toz_data_requirement
+    facets = ()
+    test_data_spec = toz_test_spec
+
+    @staticmethod
+    def update_recipe(
+        recipe: Recipe,
+        input_files: dict[SourceDatasetType, pandas.DataFrame],
+    ) -> None:
+        """Update the recipe."""
+        recipe_variables = dataframe_to_recipe(input_files[get_cmip_source_type(input_files)])
+        dataset = recipe_variables["toz"]["additional_datasets"][0]
+        # set time range of model (CMIP6) dataset (should match observational period)
+        dataset["timerange"] = "1996/2014"
+        recipe["datasets"] = [dataset]
+        diagnostic = "lat_time_mapplot"
+        recipe["diagnostics"] = {diagnostic: recipe["diagnostics"][diagnostic]}
+        recipe["diagnostics"][diagnostic]["variables"]["toz"]["timerange"] = "1996/2014"
+
+
+class O3PolarCapTimeseriesSH(ESMValToolDiagnostic):
+    """
+    Calculate the ozone diagnostics - October SH polar mean (60S-85S) time series.
+    """
+
+    name = "Ozone Diagnostics"
+    slug = "ozone-sh-oct"
+    base_recipe = "ref/recipe_ref_ozone.yml"
+
+    data_requirements = toz_data_requirement
+    facets = ()
+    test_data_spec = toz_test_spec
+
+    @staticmethod
+    def update_recipe(
+        recipe: Recipe,
+        input_files: dict[SourceDatasetType, pandas.DataFrame],
+    ) -> None:
+        """Update the recipe."""
+        recipe_variables = dataframe_to_recipe(input_files[get_cmip_source_type(input_files)])
+        dataset = recipe_variables["toz"]["additional_datasets"][0]
+        # set model (CMIP6) time range to 1950...2014
+        dataset["timerange"] = "1950/2014"
+        recipe["datasets"] = [dataset]
+        diagnostic = "polar_cap_time_series_SH"
+        recipe["diagnostics"] = {diagnostic: recipe["diagnostics"][diagnostic]}
+
+
+class O3PolarCapTimeseriesNH(ESMValToolDiagnostic):
+    """
+    Calculate the ozone diagnostics - March NH polar mean (60N-80N) time series.
+    """
+
+    name = "Ozone Diagnostics"
+    slug = "ozone-nh-mar"
+    base_recipe = "ref/recipe_ref_ozone.yml"
+
+    data_requirements = toz_data_requirement
+    facets = ()
+    test_data_spec = toz_test_spec
+
+    @staticmethod
+    def update_recipe(
+        recipe: Recipe,
+        input_files: dict[SourceDatasetType, pandas.DataFrame],
+    ) -> None:
+        """Update the recipe."""
+        # Make sure only grid cells south of 80N are considered as there are no
+        # measurements north of 80N in March. Specifying 85N as northern boundary
+        # in the orignal 'recipe_ref_ozone.yml' is a bug!
+        recipe["preprocessors"]["create_time_series_NH"]["extract_region"]["end_latitude"] = 80
+        recipe_variables = dataframe_to_recipe(input_files[get_cmip_source_type(input_files)])
+        dataset = recipe_variables["toz"]["additional_datasets"][0]
+        # set model (CMIP6) time range to 1950...2014
+        dataset["timerange"] = "1950/2014"
+        recipe["datasets"] = [dataset]
+        diagnostic = "polar_cap_time_series_NH"
+        # adjust plot title to reflect bug fix regarding northern boundary (see above)
+        recipe["diagnostics"][diagnostic]["scripts"]["plot"]["plots"]["timeseries"]["pyplot_kwargs"][
+            "title"
+        ] = "Total Column Ozone, 60-80N, March"
+        recipe["diagnostics"] = {diagnostic: recipe["diagnostics"][diagnostic]}
+
+
+class O3ZonalMeanProfiles(ESMValToolDiagnostic):
+    """
+    Calculate the ozone diagnostics - stratospheric zonal mean profiles.
+    """
+
+    name = "Ozone Diagnostics"
+    slug = "ozone-zonal"
+    base_recipe = "ref/recipe_ref_ozone.yml"
+
+    data_requirements = (
+        DataRequirement(
+            source_type=SourceDatasetType.CMIP6,
+            filters=(
+                FacetFilter(
+                    facets={
+                        "variable_id": "o3",
+                        "experiment_id": "historical",
+                        "table_id": "Amon",
+                    },
+                ),
+            ),
+            group_by=("source_id", "member_id", "grid_label"),
+            constraints=(
+                RequireTimerange(
+                    group_by=("instance_id",),
+                    start=PartialDateTime(2005, 1),
+                    end=PartialDateTime(2014, 12),
+                ),
+                RequireContiguousTimerange(group_by=("instance_id",)),
+            ),
+        ),
+        # TODO: Use ESACCI-OZONE (SAGE-OMPS, variable o3) from obs4MIPs once available.
+    )
+    facets = ()
+    test_data_spec = TestDataSpecification(
+        test_cases=(
+            TestCase(
+                name="cmip6",
+                description="Test with CMIP6 data.",
+                requests=(
+                    CMIP6Request(
+                        slug="cmip6",
+                        facets={
+                            "experiment_id": "historical",
+                            "frequency": "mon",
+                            "source_id": "GFDL-ESM4",
+                            "variable_id": "o3",
+                        },
+                        remove_ensembles=True,
+                        time_span=("1996", "2015"),
+                    ),
+                ),
+            ),
+            TestCase(
+                name="cmip7",
+                description="Test with CMIP7 data.",
+                requests=(
+                    CMIP7Request(
+                        slug="cmip7",
+                        facets={
+                            "experiment_id": ["historical"],
+                            "source_id": "GFDL-ESM4",
+                            "variable_id": "o3",
+                            "branded_variable": [
+                                "o3_tavg-al-hxy-u",
+                            ],
+                            "variant_label": "r1i1p1f1",
+                            "frequency": ["fx", "mon"],
+                            "region": "glb",
+                        },
+                        remove_ensembles=True,
+                        time_span=("1980", "2009"),
+                    ),
+                ),
+            ),
+        ),
+    )
+
+    @staticmethod
+    def update_recipe(
+        recipe: Recipe,
+        input_files: dict[SourceDatasetType, pandas.DataFrame],
+    ) -> None:
+        """Update the recipe."""
+        recipe_variables = dataframe_to_recipe(input_files[get_cmip_source_type(input_files)])
+        dataset = recipe_variables["o3"]["additional_datasets"][0]
+        # set model (CMIP6) time range to 2005...2014
+        dataset["timerange"] = "2005/2014"
+        recipe["datasets"] = [dataset]
+        diagnostic = "zonal_mean_profiles"
+        # adjust plot title to actual time range
+        recipe["diagnostics"][diagnostic]["scripts"]["plot"]["plots"]["zonal_mean_profile"]["pyplot_kwargs"][
+            "suptitle"
+        ] = "{long_name} (2005-2014 mean)"
+        recipe["diagnostics"] = {diagnostic: recipe["diagnostics"][diagnostic]}
+        recipe["diagnostics"][diagnostic]["variables"]["o3"]["timerange"] = "2005/2014"
+
+
+class O3LatMonthMapplot(ESMValToolDiagnostic):
+    """
+    Calculate the ozone diagnostics - zonal mean total column ozone vs. annual cycle plot.
+    """
+
+    name = "Ozone Diagnostics"
+    slug = "ozone-annual-cycle"
+    base_recipe = "ref/recipe_ref_ozone.yml"
+
+    data_requirements = toz_data_requirement
+    facets = ()
+    test_data_spec = toz_test_spec
+
+    @staticmethod
+    def update_recipe(
+        recipe: Recipe,
+        input_files: dict[SourceDatasetType, pandas.DataFrame],
+    ) -> None:
+        """Update the recipe."""
+        recipe_variables = dataframe_to_recipe(input_files[get_cmip_source_type(input_files)])
+        dataset = recipe_variables["toz"]["additional_datasets"][0]
+        # set model (CMIP6) time range to 2005...2014
+        dataset["timerange"] = "2005/2014"
+        recipe["datasets"] = [dataset]
+        diagnostic = "lat_month_mapplot"
+        recipe["diagnostics"] = {diagnostic: recipe["diagnostics"][diagnostic]}
+        recipe["diagnostics"][diagnostic]["variables"]["toz"]["timerange"] = "2005/2014"
diff --git a/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/recipes.txt b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/recipes.txt
index 27f0e9f82..6c4044b30 100644
--- a/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/recipes.txt
+++ b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/recipes.txt
@@ -10,6 +10,7 @@ ref/recipe_enso_characteristics.yml         34c2518b138068ac96d212910b979d54a8fc
 ref/recipe_ref_annual_cycle_region.yml      88e0c2f07a76c4de4276547badcc74091516e03840eddb1f0e62469c67a0a86d
 ref/recipe_ref_cre.yml                      4375f262479c3b3e1b348b71080a6d758e195bda76516a591182045a3a29aa32
 ref/recipe_ref_fire.yml                     2ad82effaca4e742d8abe6a0aa07bb46e1e92ef0d2d240760f7623b0ba045926
+ref/recipe_ref_ozone.yml                    388aaf01721c0856ab7143b47b9d2f1efeaaae4ef57e11572c1e133b49aad0a6
 ref/recipe_ref_sea_ice_area_basic.yml       7d01a8527880663ca28284772f83a8356d9972fb4f022a4000e50a56ce044b09
 ref/recipe_ref_scatterplot.yml              b99d1736e16256d161847b025811d7088ad9f892d4887fb009fa99c4079135a0
 ref/recipe_ref_timeseries_region.yml        deee4403ea25867401e163f6c9d7fcc4fee09d3088009007fcad6a29d01247a8
diff --git a/packages/climate-ref-esmvaltool/tests/integration/test_diagnostics.py b/packages/climate-ref-esmvaltool/tests/integration/test_diagnostics.py
index 59e1e8a10..bd4022922 100644
--- a/packages/climate-ref-esmvaltool/tests/integration/test_diagnostics.py
+++ b/packages/climate-ref-esmvaltool/tests/integration/test_diagnostics.py
@@ -22,6 +22,12 @@ def provider_test_data_dir() -> Path:
 SKIP = {
     "regional-historical-annual-cycle",
     "regional-historical-timeseries",
+    # No data in sample data catalog
+    "ozone-annual-cycle",
+    "ozone-lat-time",
+    "ozone-nh-mar",
+    "ozone-sh-oct",
+    "ozone-zonal",
 }
 
 diagnostics = [
diff --git a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_climate_at_global_warming_levels_cmip6.yml b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_climate_at_global_warming_levels_cmip6.yml
index 53200348a..da425d084 100644
--- a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_climate_at_global_warming_levels_cmip6.yml
+++ b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_climate_at_global_warming_levels_cmip6.yml
@@ -181,6 +181,18 @@ datasets:
   - historical
   grid: gn
   mip: Amon
+- project: CMIP6
+  activity:
+  - ScenarioMIP
+  - CMIP
+  dataset: GFDL-ESM4
+  ensemble: r1i1p1f1
+  institute: NOAA-GFDL
+  exp:
+  - ssp126
+  - historical
+  grid: gr1
+  mip: Amon
 - project: CMIP6
   activity:
   - ScenarioMIP
diff --git a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_annual_cycle_cmip6_obs4mips.yml b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_annual_cycle_cmip6_obs4mips.yml
new file mode 100644
index 000000000..b8763045d
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_annual_cycle_cmip6_obs4mips.yml
@@ -0,0 +1,138 @@
+documentation:
+  title: Model evaluation with focus on total column and stratospheric ozone.
+  description: 'Plot climatologies, zonal means, and selected monthly means for total
+    column ozone and stratospheric ozone for the REF.
+
+    '
+  authors:
+  - schlund_manuel
+  - hassler_birgit
+  maintainer:
+  - hassler_birgit
+preprocessors:
+  create_time_series_SH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: -85
+      end_latitude: -60
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 10
+    convert_units:
+      units: DU
+  create_time_series_NH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: 60
+      end_latitude: 85
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 3
+    convert_units:
+      units: DU
+  create_lat_time_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    regrid_time:
+      calendar: standard
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_lat_month_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    climate_statistics:
+      operator: mean
+      period: month
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_zonal_mean_profile:
+    zonal_statistics:
+      operator: mean
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    extract_levels:
+      levels:
+      - 15000
+      - 10000
+      - 7000
+      - 5000
+      - 3000
+      - 2000
+      - 1000
+      - 500
+      - 100
+      scheme: linear_extrapolate
+      coordinate: air_pressure
+    climate_statistics:
+      operator: mean
+      period: full
+    convert_units:
+      units: ppm
+datasets:
+- project: CMIP6
+  activity: CMIP
+  dataset: GFDL-ESM4
+  ensemble: r1i1p1f1
+  institute: NOAA-GFDL
+  exp: historical
+  grid: gr1
+  mip: AERmon
+  timerange: 2005/2014
+timerange_for_toz_monthly_data:
+  timerange: 1950/2014
+timerange_for_toz_zonal_mean:
+  timerange: 1997/2014
+timerange_for_ozone_profile:
+  timerange: 1990/2000
+diagnostics:
+  lat_month_mapplot:
+    variables:
+      toz:
+        timerange: 2005/2014
+        mip: AERmon
+        exp: historical
+        preprocessor: create_lat_month_map
+        additional_datasets:
+        - project: obs4MIPs
+          dataset: C3S-GTO-ECV-9-0
+          tier: 1
+          alias: GTO-ECV
+          frequency: mon
+          reference_for_monitor_diags: true
+    scripts:
+      plot:
+        script: monitor/multi_datasets.py
+        facet_used_for_labels: alias
+        plot_folder: '{plot_dir}'
+        plot_filename: '{plot_type}_{real_name}_LatTime_Map'
+        matplotlib_rc_params:
+          xtick.labelsize: 6
+          ytick.labelsize: 8
+          axes.labelsize: 8
+          axes.titlesize: 8
+        savefig_kwargs:
+          dpi: 150
+          bbox_inches: tight
+          orientation: landscape
+        plots:
+          hovmoeller_anncyc_vs_lat_or_lon:
+            common_cbar: true
+            show_x_minor_ticks: false
+            time_on: x-axis
diff --git a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_annual_cycle_cmip7_obs4mips.yml b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_annual_cycle_cmip7_obs4mips.yml
new file mode 100644
index 000000000..2dc88b34f
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_annual_cycle_cmip7_obs4mips.yml
@@ -0,0 +1,142 @@
+documentation:
+  title: Model evaluation with focus on total column and stratospheric ozone.
+  description: 'Plot climatologies, zonal means, and selected monthly means for total
+    column ozone and stratospheric ozone for the REF.
+
+    '
+  authors:
+  - schlund_manuel
+  - hassler_birgit
+  maintainer:
+  - hassler_birgit
+preprocessors:
+  create_time_series_SH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: -85
+      end_latitude: -60
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 10
+    convert_units:
+      units: DU
+  create_time_series_NH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: 60
+      end_latitude: 85
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 3
+    convert_units:
+      units: DU
+  create_lat_time_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    regrid_time:
+      calendar: standard
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_lat_month_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    climate_statistics:
+      operator: mean
+      period: month
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_zonal_mean_profile:
+    zonal_statistics:
+      operator: mean
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    extract_levels:
+      levels:
+      - 15000
+      - 10000
+      - 7000
+      - 5000
+      - 3000
+      - 2000
+      - 1000
+      - 500
+      - 100
+      scheme: linear_extrapolate
+      coordinate: air_pressure
+    climate_statistics:
+      operator: mean
+      period: full
+    convert_units:
+      units: ppm
+datasets:
+- project: CMIP7
+  activity: CMIP
+  branding_suffix: tavg-u-hxy-u
+  dataset: GFDL-ESM4
+  ensemble: r1i1p1f1
+  exp: historical
+  frequency: mon
+  grid: gr1
+  institute: NOAA-GFDL
+  mip: aerosol
+  region: glb
+  timerange: 2005/2014
+timerange_for_toz_monthly_data:
+  timerange: 1950/2014
+timerange_for_toz_zonal_mean:
+  timerange: 1997/2014
+timerange_for_ozone_profile:
+  timerange: 1990/2000
+diagnostics:
+  lat_month_mapplot:
+    variables:
+      toz:
+        timerange: 2005/2014
+        mip: aerosol
+        exp: historical
+        preprocessor: create_lat_month_map
+        additional_datasets:
+        - project: obs4MIPs
+          dataset: C3S-GTO-ECV-9-0
+          tier: 1
+          alias: GTO-ECV
+          frequency: mon
+          reference_for_monitor_diags: true
+          mip: AERmon
+    scripts:
+      plot:
+        script: monitor/multi_datasets.py
+        facet_used_for_labels: alias
+        plot_folder: '{plot_dir}'
+        plot_filename: '{plot_type}_{real_name}_LatTime_Map'
+        matplotlib_rc_params:
+          xtick.labelsize: 6
+          ytick.labelsize: 8
+          axes.labelsize: 8
+          axes.titlesize: 8
+        savefig_kwargs:
+          dpi: 150
+          bbox_inches: tight
+          orientation: landscape
+        plots:
+          hovmoeller_anncyc_vs_lat_or_lon:
+            common_cbar: true
+            show_x_minor_ticks: false
+            time_on: x-axis
diff --git a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_lat_time_cmip6_obs4mips.yml b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_lat_time_cmip6_obs4mips.yml
new file mode 100644
index 000000000..15a5c0b11
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_lat_time_cmip6_obs4mips.yml
@@ -0,0 +1,139 @@
+documentation:
+  title: Model evaluation with focus on total column and stratospheric ozone.
+  description: 'Plot climatologies, zonal means, and selected monthly means for total
+    column ozone and stratospheric ozone for the REF.
+
+    '
+  authors:
+  - schlund_manuel
+  - hassler_birgit
+  maintainer:
+  - hassler_birgit
+preprocessors:
+  create_time_series_SH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: -85
+      end_latitude: -60
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 10
+    convert_units:
+      units: DU
+  create_time_series_NH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: 60
+      end_latitude: 85
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 3
+    convert_units:
+      units: DU
+  create_lat_time_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    regrid_time:
+      calendar: standard
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_lat_month_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    climate_statistics:
+      operator: mean
+      period: month
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_zonal_mean_profile:
+    zonal_statistics:
+      operator: mean
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    extract_levels:
+      levels:
+      - 15000
+      - 10000
+      - 7000
+      - 5000
+      - 3000
+      - 2000
+      - 1000
+      - 500
+      - 100
+      scheme: linear_extrapolate
+      coordinate: air_pressure
+    climate_statistics:
+      operator: mean
+      period: full
+    convert_units:
+      units: ppm
+datasets:
+- project: CMIP6
+  activity: CMIP
+  dataset: GFDL-ESM4
+  ensemble: r1i1p1f1
+  institute: NOAA-GFDL
+  exp: historical
+  grid: gr1
+  mip: AERmon
+  timerange: 1996/2014
+timerange_for_toz_monthly_data:
+  timerange: 1950/2014
+timerange_for_toz_zonal_mean:
+  timerange: 1997/2014
+timerange_for_ozone_profile:
+  timerange: 1990/2000
+diagnostics:
+  lat_time_mapplot:
+    variables:
+      toz:
+        timerange: 1996/2014
+        mip: AERmon
+        exp: historical
+        preprocessor: create_lat_time_map
+        additional_datasets:
+        - project: obs4MIPs
+          dataset: C3S-GTO-ECV-9-0
+          tier: 1
+          alias: GTO-ECV
+          frequency: mon
+          reference_for_monitor_diags: true
+    scripts:
+      plot:
+        script: monitor/multi_datasets.py
+        facet_used_for_labels: alias
+        plot_folder: '{plot_dir}'
+        plot_filename: '{plot_type}_{real_name}_LatTime_Map'
+        matplotlib_rc_params:
+          xtick.labelsize: 6
+          ytick.labelsize: 8
+          axes.labelsize: 8
+          axes.titlesize: 8
+        savefig_kwargs:
+          dpi: 150
+          bbox_inches: tight
+          orientation: landscape
+        plots:
+          hovmoeller_time_vs_lat_or_lon:
+            common_cbar: true
+            show_x_minor_ticks: false
+            time_format: '%Y'
+            time_on: x-axis
diff --git a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_lat_time_cmip7_obs4mips.yml b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_lat_time_cmip7_obs4mips.yml
new file mode 100644
index 000000000..6c444f87b
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_lat_time_cmip7_obs4mips.yml
@@ -0,0 +1,143 @@
+documentation:
+  title: Model evaluation with focus on total column and stratospheric ozone.
+  description: 'Plot climatologies, zonal means, and selected monthly means for total
+    column ozone and stratospheric ozone for the REF.
+
+    '
+  authors:
+  - schlund_manuel
+  - hassler_birgit
+  maintainer:
+  - hassler_birgit
+preprocessors:
+  create_time_series_SH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: -85
+      end_latitude: -60
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 10
+    convert_units:
+      units: DU
+  create_time_series_NH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: 60
+      end_latitude: 85
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 3
+    convert_units:
+      units: DU
+  create_lat_time_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    regrid_time:
+      calendar: standard
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_lat_month_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    climate_statistics:
+      operator: mean
+      period: month
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_zonal_mean_profile:
+    zonal_statistics:
+      operator: mean
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    extract_levels:
+      levels:
+      - 15000
+      - 10000
+      - 7000
+      - 5000
+      - 3000
+      - 2000
+      - 1000
+      - 500
+      - 100
+      scheme: linear_extrapolate
+      coordinate: air_pressure
+    climate_statistics:
+      operator: mean
+      period: full
+    convert_units:
+      units: ppm
+datasets:
+- project: CMIP7
+  activity: CMIP
+  branding_suffix: tavg-u-hxy-u
+  dataset: GFDL-ESM4
+  ensemble: r1i1p1f1
+  exp: historical
+  frequency: mon
+  grid: gr1
+  institute: NOAA-GFDL
+  mip: aerosol
+  region: glb
+  timerange: 1996/2014
+timerange_for_toz_monthly_data:
+  timerange: 1950/2014
+timerange_for_toz_zonal_mean:
+  timerange: 1997/2014
+timerange_for_ozone_profile:
+  timerange: 1990/2000
+diagnostics:
+  lat_time_mapplot:
+    variables:
+      toz:
+        timerange: 1996/2014
+        mip: aerosol
+        exp: historical
+        preprocessor: create_lat_time_map
+        additional_datasets:
+        - project: obs4MIPs
+          dataset: C3S-GTO-ECV-9-0
+          tier: 1
+          alias: GTO-ECV
+          frequency: mon
+          reference_for_monitor_diags: true
+          mip: AERmon
+    scripts:
+      plot:
+        script: monitor/multi_datasets.py
+        facet_used_for_labels: alias
+        plot_folder: '{plot_dir}'
+        plot_filename: '{plot_type}_{real_name}_LatTime_Map'
+        matplotlib_rc_params:
+          xtick.labelsize: 6
+          ytick.labelsize: 8
+          axes.labelsize: 8
+          axes.titlesize: 8
+        savefig_kwargs:
+          dpi: 150
+          bbox_inches: tight
+          orientation: landscape
+        plots:
+          hovmoeller_time_vs_lat_or_lon:
+            common_cbar: true
+            show_x_minor_ticks: false
+            time_format: '%Y'
+            time_on: x-axis
diff --git a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_nh_mar_cmip6_obs4mips.yml b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_nh_mar_cmip6_obs4mips.yml
new file mode 100644
index 000000000..a0395b1f7
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_nh_mar_cmip6_obs4mips.yml
@@ -0,0 +1,136 @@
+documentation:
+  title: Model evaluation with focus on total column and stratospheric ozone.
+  description: 'Plot climatologies, zonal means, and selected monthly means for total
+    column ozone and stratospheric ozone for the REF.
+
+    '
+  authors:
+  - schlund_manuel
+  - hassler_birgit
+  maintainer:
+  - hassler_birgit
+preprocessors:
+  create_time_series_SH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: -85
+      end_latitude: -60
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 10
+    convert_units:
+      units: DU
+  create_time_series_NH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: 60
+      end_latitude: 80
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 3
+    convert_units:
+      units: DU
+  create_lat_time_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    regrid_time:
+      calendar: standard
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_lat_month_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    climate_statistics:
+      operator: mean
+      period: month
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_zonal_mean_profile:
+    zonal_statistics:
+      operator: mean
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    extract_levels:
+      levels:
+      - 15000
+      - 10000
+      - 7000
+      - 5000
+      - 3000
+      - 2000
+      - 1000
+      - 500
+      - 100
+      scheme: linear_extrapolate
+      coordinate: air_pressure
+    climate_statistics:
+      operator: mean
+      period: full
+    convert_units:
+      units: ppm
+datasets:
+- project: CMIP6
+  activity: CMIP
+  dataset: GFDL-ESM4
+  ensemble: r1i1p1f1
+  institute: NOAA-GFDL
+  exp: historical
+  grid: gr1
+  mip: AERmon
+  timerange: 1950/2014
+timerange_for_toz_monthly_data:
+  timerange: 1950/2014
+timerange_for_toz_zonal_mean:
+  timerange: 1997/2014
+timerange_for_ozone_profile:
+  timerange: 1990/2000
+diagnostics:
+  polar_cap_time_series_NH:
+    variables:
+      toz:
+        timerange: 1950/2014
+        mip: AERmon
+        exp: historical
+        preprocessor: create_time_series_NH
+        facet_used_for_labels: alias
+    additional_datasets:
+    - project: obs4MIPs
+      dataset: C3S-GTO-ECV-9-0
+      tier: 1
+      timerange: 1996/2021
+      alias: GTO-ECV
+      frequency: mon
+    scripts:
+      plot:
+        script: monitor/multi_datasets.py
+        plot_folder: '{plot_dir}'
+        plot_filename: '{plot_type}_{real_name}_NH_MAR'
+        facet_used_for_labels: alias
+        savefig_kwargs:
+          dpi: 150
+          bbox_inches: tight
+          orientation: landscape
+        plots:
+          timeseries:
+            plot_kwargs:
+              OBS:
+                color: black
+            pyplot_kwargs:
+              title: Total Column Ozone, 60-80N, March
diff --git a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_nh_mar_cmip7_obs4mips.yml b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_nh_mar_cmip7_obs4mips.yml
new file mode 100644
index 000000000..1fad1a667
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_nh_mar_cmip7_obs4mips.yml
@@ -0,0 +1,139 @@
+documentation:
+  title: Model evaluation with focus on total column and stratospheric ozone.
+  description: 'Plot climatologies, zonal means, and selected monthly means for total
+    column ozone and stratospheric ozone for the REF.
+
+    '
+  authors:
+  - schlund_manuel
+  - hassler_birgit
+  maintainer:
+  - hassler_birgit
+preprocessors:
+  create_time_series_SH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: -85
+      end_latitude: -60
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 10
+    convert_units:
+      units: DU
+  create_time_series_NH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: 60
+      end_latitude: 80
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 3
+    convert_units:
+      units: DU
+  create_lat_time_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    regrid_time:
+      calendar: standard
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_lat_month_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    climate_statistics:
+      operator: mean
+      period: month
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_zonal_mean_profile:
+    zonal_statistics:
+      operator: mean
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    extract_levels:
+      levels:
+      - 15000
+      - 10000
+      - 7000
+      - 5000
+      - 3000
+      - 2000
+      - 1000
+      - 500
+      - 100
+      scheme: linear_extrapolate
+      coordinate: air_pressure
+    climate_statistics:
+      operator: mean
+      period: full
+    convert_units:
+      units: ppm
+datasets:
+- project: CMIP7
+  activity: CMIP
+  branding_suffix: tavg-u-hxy-u
+  dataset: GFDL-ESM4
+  ensemble: r1i1p1f1
+  exp: historical
+  frequency: mon
+  grid: gr1
+  institute: NOAA-GFDL
+  mip: aerosol
+  region: glb
+  timerange: 1950/2014
+timerange_for_toz_monthly_data:
+  timerange: 1950/2014
+timerange_for_toz_zonal_mean:
+  timerange: 1997/2014
+timerange_for_ozone_profile:
+  timerange: 1990/2000
+diagnostics:
+  polar_cap_time_series_NH:
+    variables:
+      toz:
+        timerange: 1950/2014
+        mip: aerosol
+        exp: historical
+        preprocessor: create_time_series_NH
+        facet_used_for_labels: alias
+    additional_datasets:
+    - project: obs4MIPs
+      dataset: C3S-GTO-ECV-9-0
+      tier: 1
+      timerange: 1996/2021
+      alias: GTO-ECV
+      frequency: mon
+    scripts:
+      plot:
+        script: monitor/multi_datasets.py
+        plot_folder: '{plot_dir}'
+        plot_filename: '{plot_type}_{real_name}_NH_MAR'
+        facet_used_for_labels: alias
+        savefig_kwargs:
+          dpi: 150
+          bbox_inches: tight
+          orientation: landscape
+        plots:
+          timeseries:
+            plot_kwargs:
+              OBS:
+                color: black
+            pyplot_kwargs:
+              title: Total Column Ozone, 60-80N, March
diff --git a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_sh_oct_cmip6_obs4mips.yml b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_sh_oct_cmip6_obs4mips.yml
new file mode 100644
index 000000000..e390e8b97
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_sh_oct_cmip6_obs4mips.yml
@@ -0,0 +1,135 @@
+documentation:
+  title: Model evaluation with focus on total column and stratospheric ozone.
+  description: 'Plot climatologies, zonal means, and selected monthly means for total
+    column ozone and stratospheric ozone for the REF.
+
+    '
+  authors:
+  - schlund_manuel
+  - hassler_birgit
+  maintainer:
+  - hassler_birgit
+preprocessors:
+  create_time_series_SH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: -85
+      end_latitude: -60
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 10
+    convert_units:
+      units: DU
+  create_time_series_NH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: 60
+      end_latitude: 85
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 3
+    convert_units:
+      units: DU
+  create_lat_time_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    regrid_time:
+      calendar: standard
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_lat_month_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    climate_statistics:
+      operator: mean
+      period: month
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_zonal_mean_profile:
+    zonal_statistics:
+      operator: mean
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    extract_levels:
+      levels:
+      - 15000
+      - 10000
+      - 7000
+      - 5000
+      - 3000
+      - 2000
+      - 1000
+      - 500
+      - 100
+      scheme: linear_extrapolate
+      coordinate: air_pressure
+    climate_statistics:
+      operator: mean
+      period: full
+    convert_units:
+      units: ppm
+datasets:
+- project: CMIP6
+  activity: CMIP
+  dataset: GFDL-ESM4
+  ensemble: r1i1p1f1
+  institute: NOAA-GFDL
+  exp: historical
+  grid: gr1
+  mip: AERmon
+  timerange: 1950/2014
+timerange_for_toz_monthly_data:
+  timerange: 1950/2014
+timerange_for_toz_zonal_mean:
+  timerange: 1997/2014
+timerange_for_ozone_profile:
+  timerange: 1990/2000
+diagnostics:
+  polar_cap_time_series_SH:
+    variables:
+      toz:
+        timerange: 1950/2014
+        mip: AERmon
+        exp: historical
+        preprocessor: create_time_series_SH
+    additional_datasets:
+    - project: obs4MIPs
+      dataset: C3S-GTO-ECV-9-0
+      tier: 1
+      timerange: 1996/2021
+      alias: GTO-ECV
+      frequency: mon
+    scripts:
+      plot:
+        script: monitor/multi_datasets.py
+        plot_folder: '{plot_dir}'
+        plot_filename: '{plot_type}_{real_name}_SH_Oct'
+        facet_used_for_labels: alias
+        savefig_kwargs:
+          dpi: 150
+          bbox_inches: tight
+          orientation: landscape
+        plots:
+          timeseries:
+            plot_kwargs:
+              OBS:
+                color: black
+            pyplot_kwargs:
+              title: Total Column Ozone, 60-85S, October
diff --git a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_sh_oct_cmip7_obs4mips.yml b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_sh_oct_cmip7_obs4mips.yml
new file mode 100644
index 000000000..725d4ab5a
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/recipes/recipe_ozone_sh_oct_cmip7_obs4mips.yml
@@ -0,0 +1,138 @@
+documentation:
+  title: Model evaluation with focus on total column and stratospheric ozone.
+  description: 'Plot climatologies, zonal means, and selected monthly means for total
+    column ozone and stratospheric ozone for the REF.
+
+    '
+  authors:
+  - schlund_manuel
+  - hassler_birgit
+  maintainer:
+  - hassler_birgit
+preprocessors:
+  create_time_series_SH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: -85
+      end_latitude: -60
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 10
+    convert_units:
+      units: DU
+  create_time_series_NH:
+    annual_statistics:
+      operator: mean
+      keep_group_coordinates: true
+    area_statistics:
+      operator: mean
+    extract_region:
+      start_latitude: 60
+      end_latitude: 85
+      start_longitude: 0
+      end_longitude: 360
+    extract_month:
+      month: 3
+    convert_units:
+      units: DU
+  create_lat_time_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    regrid_time:
+      calendar: standard
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_lat_month_map:
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    climate_statistics:
+      operator: mean
+      period: month
+    zonal_statistics:
+      operator: mean
+    convert_units:
+      units: DU
+  create_zonal_mean_profile:
+    zonal_statistics:
+      operator: mean
+    regrid:
+      scheme: linear
+      target_grid: 5x5
+    extract_levels:
+      levels:
+      - 15000
+      - 10000
+      - 7000
+      - 5000
+      - 3000
+      - 2000
+      - 1000
+      - 500
+      - 100
+      scheme: linear_extrapolate
+      coordinate: air_pressure
+    climate_statistics:
+      operator: mean
+      period: full
+    convert_units:
+      units: ppm
+datasets:
+- project: CMIP7
+  activity: CMIP
+  branding_suffix: tavg-u-hxy-u
+  dataset: GFDL-ESM4
+  ensemble: r1i1p1f1
+  exp: historical
+  frequency: mon
+  grid: gr1
+  institute: NOAA-GFDL
+  mip: aerosol
+  region: glb
+  timerange: 1950/2014
+timerange_for_toz_monthly_data:
+  timerange: 1950/2014
+timerange_for_toz_zonal_mean:
+  timerange: 1997/2014
+timerange_for_ozone_profile:
+  timerange: 1990/2000
+diagnostics:
+  polar_cap_time_series_SH:
+    variables:
+      toz:
+        timerange: 1950/2014
+        mip: aerosol
+        exp: historical
+        preprocessor: create_time_series_SH
+    additional_datasets:
+    - project: obs4MIPs
+      dataset: C3S-GTO-ECV-9-0
+      tier: 1
+      timerange: 1996/2021
+      alias: GTO-ECV
+      frequency: mon
+    scripts:
+      plot:
+        script: monitor/multi_datasets.py
+        plot_folder: '{plot_dir}'
+        plot_filename: '{plot_type}_{real_name}_SH_Oct'
+        facet_used_for_labels: alias
+        savefig_kwargs:
+          dpi: 150
+          bbox_inches: tight
+          orientation: landscape
+        plots:
+          timeseries:
+            plot_kwargs:
+              OBS:
+                color: black
+            pyplot_kwargs:
+              title: Total Column Ozone, 60-85S, October
diff --git a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/test_recipes.py b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/test_recipes.py
index 8375f855b..74720bc7a 100644
--- a/packages/climate-ref-esmvaltool/tests/unit/diagnostics/test_recipes.py
+++ b/packages/climate-ref-esmvaltool/tests/unit/diagnostics/test_recipes.py
@@ -11,10 +11,24 @@
 from climate_ref.solver import solve_executions
 from climate_ref_core.datasets import SourceDatasetType
 
+SKIP = {
+    "ozone-zonal",
+}
 
-@pytest.mark.parametrize(
-    "diagnostic", [pytest.param(diagnostic, id=diagnostic.slug) for diagnostic in provider.diagnostics()]
-)
+diagnostics = [
+    pytest.param(
+        diagnostic,
+        id=diagnostic.slug,
+        marks=pytest.mark.skipif(
+            diagnostic.slug in SKIP,
+            reason="Missing datasets",
+        ),
+    )
+    for diagnostic in provider.diagnostics()
+]
+
+
+@pytest.mark.parametrize("diagnostic", diagnostics)
 def test_write_recipe(
     tmp_path: Path,
     file_regression: FileRegressionFixture,
diff --git a/packages/climate-ref-esmvaltool/tests/unit/test_provider.py b/packages/climate-ref-esmvaltool/tests/unit/test_provider.py
index bfc62b685..1c66d1c7d 100644
--- a/packages/climate-ref-esmvaltool/tests/unit/test_provider.py
+++ b/packages/climate-ref-esmvaltool/tests/unit/test_provider.py
@@ -17,6 +17,7 @@ def test_provider():
         "cloud_scatterplots.py": 5,
         "enso.py": 2,
         "regional_historical_changes.py": 3,
+        "ozone.py": 5,
     }
     n_diagnostics = sum(diagnostics_per_module.get(f.name, 1) for f in diagnostic_modules)
     assert len(provider) == n_diagnostics
diff --git a/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_annual_cycle_.yml b/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_annual_cycle_.yml
new file mode 100644
index 000000000..b9c297465
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_annual_cycle_.yml
@@ -0,0 +1,152 @@
+cmip6_gn_r1i1p1f1_EC-Earth3-AerChem__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.EC-Earth-Consortium.EC-Earth3-AerChem.historical.r1i1p1f1.AERmon.toz.gn.v20200624
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gn_r1i1p1f1_MPI-ESM-1-2-HAM__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.HAMMOZ-Consortium.MPI-ESM-1-2-HAM.historical.r1i1p1f1.AERmon.toz.gn.v20190627
+  - CMIP6.CMIP.HAMMOZ-Consortium.MPI-ESM-1-2-HAM.historical.r1i1p1f1.fx.areacella.gn.v20190627
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gn_r1i1p1f1_MRI-ESM2-0__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.MRI.MRI-ESM2-0.historical.r1i1p1f1.AERmon.toz.gn.v20200207
+  - CMIP6.CMIP.MRI.MRI-ESM2-0.historical.r1i1p1f1.fx.areacella.gn.v20190603
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gn_r1i1p1f2_UKESM1-0-LL__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.MOHC.UKESM1-0-LL.historical.r1i1p1f2.AERmon.toz.gn.v20190406
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gn_r1i1p1f2_UKESM1-1-LL__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.MOHC.UKESM1-1-LL.historical.r1i1p1f2.AERmon.toz.gn.v20220512
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gn_r1i1p3f1_GISS-E2-1-G__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.NASA-GISS.GISS-E2-1-G.historical.r1i1p3f1.AERmon.toz.gn.v20220525
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gn_r1i1p3f1_GISS-E2-1-H__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.NASA-GISS.GISS-E2-1-H.historical.r1i1p3f1.AERmon.toz.gn.v20220525
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gn_r1i1p3f1_GISS-E2-2-G__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.NASA-GISS.GISS-E2-2-G.historical.r1i1p3f1.AERmon.toz.gn.v20211020
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gn_r1i1p4f2_MIROC-ES2H__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.MIROC.MIROC-ES2H.historical.r1i1p4f2.AERmon.toz.gn.v20220322
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gr1_r1i1p1f1_GFDL-ESM4__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.NOAA-GFDL.GFDL-ESM4.historical.r1i1p1f1.AERmon.toz.gr1.v20190726
+  - CMIP6.CMIP.NOAA-GFDL.GFDL-ESM4.historical.r1i1p1f1.fx.areacella.gr1.v20190726
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gr_r1i1p1f1_IPSL-CM5A2-INCA__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.IPSL.IPSL-CM5A2-INCA.historical.r1i1p1f1.AERmon.toz.gr.v20200729
+  - CMIP6.CMIP.IPSL.IPSL-CM5A2-INCA.historical.r1i1p1f1.fx.areacella.gr.v20200729
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gr_r1i1p1f1_IPSL-CM6A-LR-INCA__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.IPSL.IPSL-CM6A-LR-INCA.historical.r1i1p1f1.AERmon.toz.gr.v20210216
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gr_r1i1p1f2_CNRM-CM6-1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
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+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
diff --git a/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_lat_time_.yml b/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_lat_time_.yml
new file mode 100644
index 000000000..b9c297465
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_lat_time_.yml
@@ -0,0 +1,152 @@
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new file mode 100644
index 000000000..b9c297465
--- /dev/null
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diff --git a/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_sh_oct_.yml b/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_sh_oct_.yml
new file mode 100644
index 000000000..b9c297465
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_sh_oct_.yml
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+cmip6_gn_r1i1p3f1_GISS-E2-1-H__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.NASA-GISS.GISS-E2-1-H.historical.r1i1p3f1.AERmon.toz.gn.v20220525
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gn_r1i1p3f1_GISS-E2-2-G__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.NASA-GISS.GISS-E2-2-G.historical.r1i1p3f1.AERmon.toz.gn.v20211020
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gn_r1i1p4f2_MIROC-ES2H__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.MIROC.MIROC-ES2H.historical.r1i1p4f2.AERmon.toz.gn.v20220322
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gr1_r1i1p1f1_GFDL-ESM4__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.NOAA-GFDL.GFDL-ESM4.historical.r1i1p1f1.AERmon.toz.gr1.v20190726
+  - CMIP6.CMIP.NOAA-GFDL.GFDL-ESM4.historical.r1i1p1f1.fx.areacella.gr1.v20190726
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gr_r1i1p1f1_IPSL-CM5A2-INCA__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.IPSL.IPSL-CM5A2-INCA.historical.r1i1p1f1.AERmon.toz.gr.v20200729
+  - CMIP6.CMIP.IPSL.IPSL-CM5A2-INCA.historical.r1i1p1f1.fx.areacella.gr.v20200729
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gr_r1i1p1f1_IPSL-CM6A-LR-INCA__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.IPSL.IPSL-CM6A-LR-INCA.historical.r1i1p1f1.AERmon.toz.gr.v20210216
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gr_r1i1p1f2_CNRM-CM6-1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.CNRM-CERFACS.CNRM-CM6-1.historical.r1i1p1f2.AERmon.toz.gr.v20180917
+  - CMIP6.CMIP.CNRM-CERFACS.CNRM-CM6-1.historical.r1i1p1f2.fx.areacella.gr.v20180917
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip6_gr_r1i1p1f2_CNRM-ESM2-1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip6:
+  - CMIP6.CMIP.CNRM-CERFACS.CNRM-ESM2-1.historical.r13i1p1f2.fx.areacella.gr.v20250328
+  - CMIP6.CMIP.CNRM-CERFACS.CNRM-ESM2-1.historical.r1i1p1f2.AERmon.toz.gr.v20181206
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gn_EC-Earth3-AerChem_r1i1p1f1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.EC-Earth-Consortium.EC-Earth3-AerChem.historical.r1i1p1f1.glb.mon.toz.tavg-u-hxy-u.gn.v20200624
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gn_GISS-E2-1-G_r1i1p3f1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.NASA-GISS.GISS-E2-1-G.historical.r1i1p3f1.glb.mon.toz.tavg-u-hxy-u.gn.v20220525
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gn_GISS-E2-1-H_r1i1p3f1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.NASA-GISS.GISS-E2-1-H.historical.r1i1p3f1.glb.mon.toz.tavg-u-hxy-u.gn.v20220525
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gn_GISS-E2-2-G_r1i1p3f1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.NASA-GISS.GISS-E2-2-G.historical.r1i1p3f1.glb.mon.toz.tavg-u-hxy-u.gn.v20211020
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gn_MIROC-ES2H_r1i1p4f2__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.MIROC.MIROC-ES2H.historical.r1i1p4f2.glb.mon.toz.tavg-u-hxy-u.gn.v20220322
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gn_MPI-ESM-1-2-HAM_r1i1p1f1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.HAMMOZ-Consortium.MPI-ESM-1-2-HAM.historical.r1i1p1f1.glb.fx.areacella.ti-u-hxy-u.gn.v20190627
+  - CMIP7.CMIP.HAMMOZ-Consortium.MPI-ESM-1-2-HAM.historical.r1i1p1f1.glb.mon.toz.tavg-u-hxy-u.gn.v20190627
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gn_MRI-ESM2-0_r1i1p1f1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.MRI.MRI-ESM2-0.historical.r1i1p1f1.glb.fx.areacella.ti-u-hxy-u.gn.v20190603
+  - CMIP7.CMIP.MRI.MRI-ESM2-0.historical.r1i1p1f1.glb.mon.toz.tavg-u-hxy-u.gn.v20200207
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gn_UKESM1-0-LL_r1i1p1f2__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.MOHC.UKESM1-0-LL.historical.r1i1p1f2.glb.mon.toz.tavg-u-hxy-u.gn.v20190406
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gn_UKESM1-1-LL_r1i1p1f2__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.MOHC.UKESM1-1-LL.historical.r1i1p1f2.glb.mon.toz.tavg-u-hxy-u.gn.v20220512
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gr1_GFDL-ESM4_r1i1p1f1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.NOAA-GFDL.GFDL-ESM4.historical.r1i1p1f1.glb.fx.areacella.ti-u-hxy-u.gr1.v20190726
+  - CMIP7.CMIP.NOAA-GFDL.GFDL-ESM4.historical.r1i1p1f1.glb.mon.toz.tavg-u-hxy-u.gr1.v20190726
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gr_CNRM-CM6-1_r1i1p1f2__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.CNRM-CERFACS.CNRM-CM6-1.historical.r1i1p1f2.glb.fx.areacella.ti-u-hxy-u.gr.v20180917
+  - CMIP7.CMIP.CNRM-CERFACS.CNRM-CM6-1.historical.r1i1p1f2.glb.mon.toz.tavg-u-hxy-u.gr.v20180917
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gr_CNRM-ESM2-1_r1i1p1f2__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.CNRM-CERFACS.CNRM-ESM2-1.historical.r13i1p1f2.glb.fx.areacella.ti-u-hxy-u.gr.v20250328
+  - CMIP7.CMIP.CNRM-CERFACS.CNRM-ESM2-1.historical.r1i1p1f2.glb.mon.toz.tavg-u-hxy-u.gr.v20181206
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gr_IPSL-CM5A2-INCA_r1i1p1f1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.IPSL.IPSL-CM5A2-INCA.historical.r1i1p1f1.glb.fx.areacella.ti-u-hxy-u.gr.v20200729
+  - CMIP7.CMIP.IPSL.IPSL-CM5A2-INCA.historical.r1i1p1f1.glb.mon.toz.tavg-u-hxy-u.gr.v20200729
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
+cmip7_gr_IPSL-CM6A-LR-INCA_r1i1p1f1__obs4mips_C3S-GTO-ECV-9-0:
+  cmip7:
+  - CMIP7.CMIP.IPSL.IPSL-CM6A-LR-INCA.historical.r1i1p1f1.glb.mon.toz.tavg-u-hxy-u.gr.v20210216
+  obs4mips:
+  - obs4MIPs.obs4MIPs.DLR-BIRA.C3S-GTO-ECV-9-0.mon.toz.1x1degree.gn.v20231115
diff --git a/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_zonal_.yml b/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_zonal_.yml
new file mode 100644
index 000000000..0967ef424
--- /dev/null
+++ b/packages/climate-ref-esmvaltool/tests/unit/test_solve_regression/test_solve_regression_ozone_zonal_.yml
@@ -0,0 +1 @@
+{}
diff --git a/packages/climate-ref/src/climate_ref/conftest_plugin.py b/packages/climate-ref/src/climate_ref/conftest_plugin.py
index 96761d275..0bf5a7c62 100644
--- a/packages/climate-ref/src/climate_ref/conftest_plugin.py
+++ b/packages/climate-ref/src/climate_ref/conftest_plugin.py
@@ -178,7 +178,7 @@ def esgf_data_catalog_trimmed(
     result = {}
     for source_type, df in esgf_solve_catalog.items():
         if source_type in (SourceDatasetType.CMIP6, SourceDatasetType.CMIP7):
-            source_ids = ["ACCESS-ESM1-5", "CESM2", "MPI-ESM1-2-LR"]
+            source_ids = ["ACCESS-ESM1-5", "CESM2", "MPI-ESM1-2-LR", "GFDL-ESM4"]
             result[source_type] = df[df["source_id"].isin(source_ids)]
         else:
             result[source_type] = df
diff --git a/scripts/extract-data-request-mappings.py b/scripts/extract-data-request-mappings.py
index b3adbafe9..757e02f2e 100644
--- a/scripts/extract-data-request-mappings.py
+++ b/scripts/extract-data-request-mappings.py
@@ -93,6 +93,7 @@
     "ts",
     # Ozone
     "toz",
+    "o3",
     # Atmosphere: winds
     "tauu",
     "ua",
diff --git a/scripts/fetch-esgf.py b/scripts/fetch-esgf.py
index ad05a97d0..9538ca5ce 100644
--- a/scripts/fetch-esgf.py
+++ b/scripts/fetch-esgf.py
@@ -248,11 +248,18 @@ def fetch(self, remove_ensembles: bool = True):
     CMIP6Request(
         id="esmvaltool-ozone",
         facets=dict(
-            variable_id=["toz"],
+            variable_id=["toz", "o3"],
             experiment_id=["historical"],
             table_id="AERmon",
         ),
     ),
+    Obs4MIPsRequest(
+        id="esmvaltool-ozone-obs4mips",
+        facets=dict(
+            source_id="C3S-GTO-ECV-9-0",
+            variable_id="toz",
+        ),
+    ),
     # ILAMB data
     CMIP6Request(
         id="ilamb-data",
diff --git a/tests/test-data/esgf-catalog/obs4mips_catalog.parquet b/tests/test-data/esgf-catalog/obs4mips_catalog.parquet
index 37d84e4cc..013db46c1 100644
Binary files a/tests/test-data/esgf-catalog/obs4mips_catalog.parquet and b/tests/test-data/esgf-catalog/obs4mips_catalog.parquet differ