diff --git a/au.org.access-nri/model/output/file-metadata/2-1-0/2-1-0.json b/au.org.access-nri/model/output/file-metadata/2-1-0/2-1-0.json
index ed32c50..9c40887 100644
--- a/au.org.access-nri/model/output/file-metadata/2-1-0/2-1-0.json
+++ b/au.org.access-nri/model/output/file-metadata/2-1-0/2-1-0.json
@@ -10,6 +10,14 @@
     },
     "variables": {
       "type": "object",
+      "properties": {
+        "time": {
+          "$ref": "variable/time.json"
+        },
+        "time_bnds": {
+          "$ref": "variable/time_bnds.json"
+        }
+      },
       "patternProperties": {
         "^.+$": {
           "$ref": "variable.json"
diff --git a/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time.json b/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time.json
new file mode 100644
index 0000000..bce0f45
--- /dev/null
+++ b/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time.json
@@ -0,0 +1,35 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "variable/time.json",
+  "title": "time",
+  "description": "The time variable for the dataset.",
+  "type": "object",
+  "required": [
+    "axis",
+    "calendar",
+    "long_name",
+    "standard_name",
+    "units"
+  ],
+  "properties": {
+    "axis": {
+      "const": "T"
+    },
+    "bounds": {
+      "const": "time_bnds"
+    },
+    "calendar": {
+      "$ref": "time/calendar.json"
+    },
+    "long_name": {
+      "const": "time"
+    },
+    "standard_name": {
+      "const": "time"
+    },
+    "units": {
+      "$ref": "time/units.json"
+    }
+  },
+  "additionalProperties": false
+}
diff --git a/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time/calendar.json b/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time/calendar.json
new file mode 100644
index 0000000..0109b53
--- /dev/null
+++ b/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time/calendar.json
@@ -0,0 +1,19 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "variable/time/calendar.json",
+  "title": "calendar",
+  "description": "Calendar defines the set of valid datetimes and their order. Follows the CF-Convention names using lower-case strings. It is recommended that \"proleptic_gregorian\" is used for data with leap days and \"no_leap\"/\"365_day\" for data without leap days.",
+  "type": "string",
+  "enum": [
+    "standard",
+    "julian",
+    "proleptic_gregorian",
+    "no_leap",
+    "365_day",
+    "all_leap",
+    "366_day",
+    "360_day",
+    "utc",
+    "tai"
+  ]
+}
diff --git a/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time/units.json b/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time/units.json
new file mode 100644
index 0000000..a358c57
--- /dev/null
+++ b/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time/units.json
@@ -0,0 +1,14 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "variable/time/units.json",
+  "title": "units",
+  "description": "Units for time should be given as \"days since X\" where X is a date (yyyy-mm-dd) or a datetime (yyyy-mm-dd HH:MM or yyyy-mm-dd HH:MM:SS)",
+  "examples": [
+    "days since 0001-01-01 00:00:00",
+    "days since 0001-01-01 00:00",
+    "days since 1970-01-01",
+    "days since -5000-12-25"
+  ],
+  "type": "string",
+  "pattern": "^days since -?\\d{4}-(1[012]|0[1-9])-(3[01]|[12][0-9]|0[1-9])( ([01][0-9]|2[0-3]):[0-5][0-9](:[0-5][0-9])?)?$"
+}
diff --git a/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time_bnds.json b/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time_bnds.json
new file mode 100644
index 0000000..41147fd
--- /dev/null
+++ b/au.org.access-nri/model/output/file-metadata/2-1-0/variable/time_bnds.json
@@ -0,0 +1,7 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "variable/time_bnds.json",
+  "title": "time_bnds",
+  "description": "The time_bnds variable for the dataset. Note this variable has no attributes.",
+  "const": {}
+}
diff --git a/tests/2-1-0/test.json b/tests/2-1-0/test.json
index 7191d75..64938b0 100644
--- a/tests/2-1-0/test.json
+++ b/tests/2-1-0/test.json
@@ -38,6 +38,16 @@
                         "standard_name": "latitude",
                         "units": "degrees_north",
                         "long_name": "latitude"
+                    },
+                    "time": {
+                        "axis": "T",
+                        "bounds": "time_bnds",
+                        "calendar": "proleptic_gregorian",
+                        "long_name": "time",
+                        "standard_name": "time",
+                        "units": "days since 0001-01-01 00:00"
+                    },
+                    "time_bnds": {
                     }
                 }
             }
diff --git a/tests/2-1-0/variable/test_time.json b/tests/2-1-0/variable/test_time.json
new file mode 100644
index 0000000..0b8b407
--- /dev/null
+++ b/tests/2-1-0/variable/test_time.json
@@ -0,0 +1,51 @@
+{
+    "target": "../../../au.org.access-nri/model/output/file-metadata/2-1-0/variable/time.json",
+    "tests": [
+        {
+            "description": "Full valid time variable",
+            "valid": true,
+            "data": {
+                "axis": "T",
+                "bounds": "time_bnds",
+                "calendar": "proleptic_gregorian",
+                "long_name": "time",
+                "standard_name": "time",
+                "units": "days since 0000-01-01"
+            }
+        },
+        {
+            "description": "Full valid time variable without bounds",
+            "valid": true,
+            "data": {
+                "axis": "T",
+                "calendar": "proleptic_gregorian",
+                "long_name": "time",
+                "standard_name": "time",
+                "units": "days since 0000-01-01"
+            }
+        },
+        {
+            "description": "Missing required (long_name)",
+            "valid": false,
+            "data": {
+                "axis": "T",
+                "bounds": "time_bnds",
+                "calendar": "proleptic_gregorian",
+                "standard_name": "time",
+                "units": "days since 0000-01-01"
+            }
+        },
+        {
+            "description": "Const doesn't match",
+            "valid": false,
+            "data": {
+                "axis": "T",
+                "bounds": "time_bounds",
+                "calendar": "proleptic_gregorian",
+                "long_name": "time",
+                "standard_name": "time",
+                "units": "days since 0000-01-01"
+            }
+        }
+    ]
+}
diff --git a/tests/2-1-0/variable/time/test_calendar.json b/tests/2-1-0/variable/time/test_calendar.json
new file mode 100644
index 0000000..c011919
--- /dev/null
+++ b/tests/2-1-0/variable/time/test_calendar.json
@@ -0,0 +1,25 @@
+{
+    "target": "../../../../au.org.access-nri/model/output/file-metadata/2-1-0/variable/time/calendar.json",
+    "tests": [
+        {
+            "description": "Valid calendar",
+            "valid": true,
+            "data": "proleptic_gregorian"
+        },
+        {
+            "description": "Valid calendar but capitalised",
+            "valid": false,
+            "data": "PROLEPTIC_GREGORIAN"
+        },
+        {
+            "description": "Invalid calendar",
+            "valid": false,
+            "data": "invalid_calendar"
+        },
+        {
+            "description": "Not even a string",
+            "valid": false,
+            "data": 6
+        }
+    ]
+}
diff --git a/tests/2-1-0/variable/time/test_units.json b/tests/2-1-0/variable/time/test_units.json
new file mode 100644
index 0000000..0a202d9
--- /dev/null
+++ b/tests/2-1-0/variable/time/test_units.json
@@ -0,0 +1,40 @@
+{
+    "target": "../../../../au.org.access-nri/model/output/file-metadata/2-1-0/variable/time/units.json",
+    "tests": [
+        {
+            "description": "Valid units for time",
+            "valid": true,
+            "data": "days since 0001-01-01 00:00:00"
+        },
+        {
+            "description": "Valid units for time - no seconds",
+            "valid": true,
+            "data": "days since 0001-01-01 00:00"
+        },
+        {
+            "description": "Valid units for time - no time",
+            "valid": true,
+            "data": "days since 0001-01-01"
+        },
+        {
+            "description": "Invalid units for time - not real time",
+            "valid": false,
+            "data": "days since 0001-01-01 00:00:61"
+        },
+        {
+            "description": "Invalid units for time - not days",
+            "valid": false,
+            "data": "seconds since 0001-01-01 00:00:00"
+        },
+        {
+            "description": "Invalid units for time",
+            "valid": false,
+            "data": "not even close to valid"
+        },
+        {
+            "description": "Invalid units for time - not a string",
+            "valid": false,
+            "data": 5
+        }
+    ]
+}