{
  "acquisition": {
    "bounded_data_availability_release_ready": false,
    "complete_mandatory_harvest": true,
    "data_availability_publication_allowed": true,
    "fallback_source_used": null,
    "mandatory_context_status": "passed",
    "mandatory_failures": [],
    "preferred_source_advisories": [],
    "preferred_source_degraded": false,
    "primary_measurement_status": "passed",
    "status": "passed"
  },
  "assessment": {
    "clean_air_inference_allowed": false,
    "england_wide_current_assessment_allowed": false,
    "fresh_data_available": true,
    "message": "No England-wide current environmental assessment is published because the governed monitoring coverage and freshness gate was not met.",
    "public_label": "ASSESSMENT UNAVAILABLE",
    "publication_kind": "data_coverage_status",
    "screening_event_count": 0,
    "status": "not_assessable_incomplete_england_coverage"
  },
  "claim_boundary": "Screening evidence only — no source attribution, causal finding, permit-breach determination, exposure estimate or health conclusion.",
  "contract_sha256": "8633aec1bee57f8c8754b3604662ee846b64c112568a61d0615999b536c97e42",
  "convergence": {
    "applicable_join_count": 0,
    "catalogue_pending_is_episode_evidence": false,
    "catalogue_pending_or_blocked_join_count": 11,
    "dimensions_without_executed_episode_linkage": [
      "comparator_and_background",
      "official_meteorology",
      "fire_and_satellite_context",
      "regulatory_and_operational_context"
    ],
    "dimensions_without_operational_sources": [],
    "dimensions_without_quality_validated_sources": [
      "official_meteorology",
      "traffic_activity",
      "regional_model_context",
      "fire_and_satellite_context",
      "regulatory_and_operational_context",
      "competing_source_assessment"
    ],
    "dimensions_without_registered_candidate_sources": [],
    "dimensions_without_validated_episode_linkage": [
      "comparator_and_background",
      "official_meteorology"
    ],
    "episode_pending_or_blocked_join_count": 0,
    "executed_join_count": 0,
    "execution_attempt_count": 0,
    "message": "No episode was available for corroboration. Cross-source convergence was not applicable to an episode in this run.",
    "required_dimension_count": 10,
    "status": "not_assessable_no_fresh_screening_events",
    "validated_join_count": 0
  },
  "denominators": {
    "counts": {
      "catalogued_candidate_sites": {
        "definition": "Provider or catalogue site identities considered before physical-site resolution and current-value checks.",
        "label": "catalogued candidate monitoring-site identities",
        "scope": "current live monitoring screen",
        "unit": "site identities",
        "value": 133
      },
      "configured_pollutant_streams": {
        "definition": "Unique source/station/pollutant/method/unit/averaging-period monitoring streams.",
        "label": "configured pollutant time series",
        "scope": "current live monitoring screen",
        "unit": "time series",
        "value": 237
      },
      "eligible_pm25_screening_assessments": {
        "definition": "PM2.5 station/time-series assessments meeting the current freshness, completeness and quality criteria.",
        "label": "eligible PM2.5 screening assessments",
        "scope": "current operational PM2.5 screen",
        "unit": "assessments",
        "value": 68
      },
      "england_active_aurn_sites": {
        "definition": "Active English AURN sites discovered for the completed 30-day official-monitoring review.",
        "label": "active English AURN sites discovered",
        "scope": "England 30-day review",
        "unit": "AURN sites",
        "value": 172
      },
      "england_configured_review_stations": {
        "definition": "English AURN stations configured for at least one review pollutant in the 30-day review.",
        "label": "configured pollutant-monitor stations",
        "scope": "England 30-day review",
        "unit": "stations",
        "value": 143
      },
      "england_expected_configured_pollutant_day_observations": {
        "definition": "Configured station/pollutant streams multiplied by eligible days in the review window.",
        "label": "expected configured pollutant-day observations",
        "scope": "England 30-day review",
        "unit": "pollutant-day observations",
        "value": 9872
      },
      "england_reporting_review_stations": {
        "definition": "Configured English AURN stations contributing at least one valid daily mean during the review period.",
        "label": "reporting stations in the 30-day review",
        "scope": "England 30-day review",
        "unit": "stations",
        "value": 142
      },
      "england_unique_station_days": {
        "definition": "Distinct station/date pairs contributing at least one valid pollutant daily mean.",
        "label": "unique station-days with valid evidence",
        "scope": "England 30-day review",
        "unit": "unique station-days",
        "value": 4201
      },
      "england_valid_pollutant_day_observations": {
        "definition": "Valid station/date/pollutant daily-mean rows in the England 30-day review.",
        "label": "valid pollutant-day observations",
        "scope": "England 30-day review",
        "unit": "pollutant-day observations",
        "value": 9491
      },
      "fresh_physical_sites": {
        "definition": "Resolved physical sites with at least one usable observation inside the declared freshness window.",
        "label": "fresh resolved physical monitoring sites",
        "scope": "current live monitoring screen",
        "unit": "physical sites",
        "value": 124
      },
      "fresh_pollutant_streams": {
        "definition": "Configured streams with recent usable observations inside the declared freshness window.",
        "label": "fresh pollutant time series",
        "scope": "current live monitoring screen",
        "unit": "time series",
        "value": 175
      },
      "numeric_reporting_sites": {
        "definition": "Resolved physical sites with at least one numeric observation in the current provider response.",
        "label": "resolved physical sites returning numeric data",
        "scope": "current live monitoring screen",
        "unit": "physical sites",
        "value": 132
      },
      "numeric_reporting_streams": {
        "definition": "Configured streams with at least one numeric observation in the current provider response.",
        "label": "pollutant time series returning numeric data",
        "scope": "current live monitoring screen",
        "unit": "time series",
        "value": 235
      },
      "resolved_physical_sites": {
        "definition": "Distinct physical monitoring locations after governed site-identity reconciliation.",
        "label": "resolved physical monitoring sites",
        "scope": "current live monitoring screen",
        "unit": "physical sites",
        "value": 133
      }
    },
    "percentages": {
      "england_configured_stream_day_completeness_pct": {
        "denominator": "england_expected_configured_pollutant_day_observations",
        "numerator": "england_valid_pollutant_day_observations",
        "value": 96.1
      },
      "england_reporting_station_coverage_pct": {
        "denominator": "england_configured_review_stations",
        "numerator": "england_reporting_review_stations",
        "value": 99.3
      },
      "fresh_physical_site_coverage_pct": {
        "denominator": "resolved_physical_sites",
        "numerator": "fresh_physical_sites",
        "value": 93.2
      },
      "fresh_stream_coverage_pct": {
        "denominator": "configured_pollutant_streams",
        "numerator": "fresh_pollutant_streams",
        "value": 73.8
      }
    },
    "rule": "Every public percentage must name one numerator key and one denominator key from this registry.",
    "schema": "aq26_denominator_registry_v1"
  },
  "england_30_day_review": {
    "active_aurn_sites_discovered": 172,
    "configured_stream_day_completeness_percent": 96.1,
    "configured_target_pollutant_station_count": 143,
    "data_posture": "provisional and ratified official AURN automatic measurements, status flags preserved",
    "definitions": {
      "configured_stream_day_completeness": "Valid pollutant-day observations divided by expected configured pollutant-day observations.",
      "pollutant_day_observation": "One valid station/date/pollutant daily-mean row.",
      "unique_station_day": "One distinct station/date pair with at least one valid pollutant daily mean.",
      "who_context_pollutant_day_observation": "A valid pollutant-day observation above the pollutant-specific WHO 2021 24-hour contextual reference; not a UK legal exceedance."
    },
    "expected_configured_pollutant_day_observations": 9872,
    "provisional_or_as_supplied_pollutant_day_observations": 9491,
    "provisional_or_as_supplied_station_days": 9491,
    "provisional_status_public_label": "Official automatic monitoring data are provisional or as supplied unless explicitly marked ratified and may later be revised by the original provider.",
    "ratified_pollutant_day_observations": 0,
    "ratified_station_days": 0,
    "reporting_station_count": 142,
    "schema": "aq26_public_england_metrics_v2",
    "unique_station_days": 4201,
    "valid_pollutant_day_observations": 9491,
    "who_context_pollutant_day_observations": 189,
    "who_context_pollutant_day_observations_by_pollutant": {
      "NO2": 160,
      "PM10": 2,
      "PM2.5": 27
    },
    "who_context_station_days": 189,
    "who_context_station_days_by_pollutant": {
      "NO2": 160,
      "PM10": 2,
      "PM2.5": 27
    }
  },
  "generated_at_utc": "2026-09-11T12:54:06+00:00",
  "measurement": {
    "analysis_window_valid_observation_count": 15066,
    "catalogued_candidate_site_count": 133,
    "count_definitions": {
      "analysis_window_valid_observation_count": "Quality-accepted numeric observations inside the exact AQ26 analysis window.",
      "physical_site_count": "Deduplicated physical monitoring locations, counted independently of pollutant streams.",
      "provider_expected_slot_count": "Provider timetable slots returned across selected series and lookback.",
      "provider_missing_slot_count": "Expected provider slots without a numeric observation.",
      "provider_numeric_observation_count": "Timestamped numeric provider observations; blank timetable slots excluded.",
      "provider_site_identity_count": "Provider site identities before canonical physical-site resolution; not an additional physical-site count.",
      "reporting_physical_site_count": "Canonically resolved physical sites with at least one quality-accepted observation inside the current analysis window.",
      "reporting_provider_site_identity_count": "Provider site identities returning numeric data before canonical physical-site resolution.",
      "timeseries_count": "Unique monitoring streams defined by source, station, pollutant, method, unit and averaging period."
    },
    "count_reconciliation_passed": true,
    "data_capture_percent": 96.3,
    "eligible_pm25_screening_assessment_count": 68,
    "empty_timeseries_count": 2,
    "fresh_physical_site_count": 124,
    "fresh_physical_site_coverage_pct": 93,
    "fresh_timeseries_count": 175,
    "freshness_diagnostic": {
      "claim_boundary": "This diagnostic concerns data recency and provider/network timing only. It does not describe air quality, source contribution, compliance, exposure or health risk.",
      "fresh_reporting_site_count": 124,
      "freshness_threshold_hours": 4.0,
      "interpretation": "Some reporting sites met the freshness threshold and others did not.",
      "lag_pattern": "mixed_fresh_and_stale_sites",
      "median_reporting_age_hours": 1.89,
      "newest_reporting_age_hours": 1.89,
      "no_numeric_data_site_count": 1,
      "oldest_reporting_age_hours": 54.89,
      "reporting_site_count": 132,
      "similar_timestamp_cluster_share": 0.879,
      "stale_reporting_site_count": 8,
      "status": "partial_freshness"
    },
    "identified_physical_site_count": 133,
    "median_reporting_age_hours": 1.89,
    "newest_reporting_age_hours": 1.89,
    "oldest_reporting_age_hours": 54.89,
    "physical_site_count": 133,
    "pollutant_label": "PM₁₀ and PM₂.₅",
    "pollutants": {
      "pm10": 110,
      "pm2_5": 127
    },
    "provider_expected_slot_count": 15652,
    "provider_lag_pattern": "mixed_fresh_and_stale_sites",
    "provider_missing_slot_count": 0,
    "provider_numeric_observation_count": 15652,
    "quality_flags": {
      "incomplete_24h": 9,
      "invalid_latest_values": 8,
      "missing_coordinates": 0,
      "negative_sentinels_removed": 28,
      "no_recent_values": 2,
      "stale_over_4h": 60
    },
    "reporting_physical_site_count": 132,
    "reporting_timeseries_count": 235,
    "timeseries_count": 237
  },
  "meteorology": {
    "event_alignment_applicable": false,
    "official_records_acquired": 576,
    "status": "official_meteorology_acquired_no_event_alignment_not_applicable"
  },
  "primary_source": {
    "acquisition_mode": "network_spatially_balanced_fallback",
    "analysis_driver": "current_measurements",
    "fallback_reason": null,
    "fallback_used": false,
    "geographic_scope": "official UK-AIR monitoring selected for England Phase 1",
    "geographic_scope_short": "England candidate network",
    "id": "uk_air_sos_current_particle",
    "legacy_targets_used": false,
    "name": "Defra UK-AIR Sensor Observation Service",
    "selection_method": "network_spatially_balanced_pollutant_round_robin",
    "stage": "quality_validated"
  },
  "programme": {
    "cadence": "daily",
    "coverage_scope": "official UK-AIR monitoring selected for England Phase 1",
    "coverage_status": "england_registry_reconciled_current_assessment_withheld",
    "deferred_nations": [
      "Scotland",
      "Wales",
      "Northern Ireland"
    ],
    "discovery_mode": "england_data_led_target_neutral",
    "england_wide_current_assessment_allowed": false,
    "fresh_regions_evidenced": [
      "East Midlands",
      "East of England",
      "London",
      "North East",
      "North West",
      "South East",
      "South West",
      "West Midlands",
      "Yorkshire and the Humber"
    ],
    "legacy_drive_scientific_influence": false,
    "legacy_targets_analysis_driver": false,
    "programme_label": "England operational phase",
    "regions_evidenced": [
      "East Midlands",
      "East of England",
      "London",
      "North East",
      "North West",
      "South East",
      "South West",
      "West Midlands",
      "Yorkshire and the Humber"
    ],
    "regions_not_evidenced": [],
    "scc_process": [
      "Search",
      "Corroborate",
      "Communicate"
    ],
    "scope": "England",
    "uk_ready_architecture": true,
    "vvip_process": [
      "Validation",
      "Verification",
      "Integrity",
      "Provenance"
    ]
  },
  "readiness_gates": [
    {
      "key": "comparator_checked",
      "kind": "not_applicable",
      "status": "not_applicable_no_fresh_screening_events_monitor_roles_pending"
    },
    {
      "key": "meteorology_checked",
      "kind": "partial",
      "status": "official_meteorology_acquired_no_event_alignment_not_applicable"
    },
    {
      "key": "monitor_role_checked",
      "kind": "partial",
      "status": "candidate_monitor_roles_unvalidated"
    },
    {
      "key": "parser_validated",
      "kind": "complete",
      "status": "quality_validated_current_measurements"
    },
    {
      "key": "provenance_recorded",
      "kind": "complete",
      "status": "complete_current_measurement_provenance"
    },
    {
      "key": "reviewer_challenge_recorded",
      "kind": "partial",
      "status": "claim_framework_started"
    },
    {
      "key": "source_acquired",
      "kind": "complete",
      "status": "complete_primary_measurements"
    },
    {
      "key": "time_alignment_checked",
      "kind": "not_applicable",
      "status": "not_applicable_no_fresh_screening_events"
    }
  ],
  "release": {
    "bounded_data_availability_release_ready": false,
    "cadence": "daily",
    "complete_mandatory_harvest": true,
    "countrywide_programme": false,
    "coverage_status": "england_registry_reconciled_current_assessment_withheld",
    "england_operational_phase": true,
    "england_wide_current_assessment_allowed": false,
    "fallback_source_used": null,
    "full_preferred_source_release_ready": false,
    "harvest_integrity": "passed",
    "mandatory_context_harvest_status": "passed",
    "mandatory_harvest_failures": [],
    "missing_dimensions": [],
    "preferred_source_advisories": [],
    "preferred_source_degraded": false,
    "primary_measurement_acquisition_integrity": "passed",
    "public_wording": "Acquisition status distinguishes primary monitoring evidence from mandatory contextual sources. A degraded context harvest may support a clearly labelled data-availability release, but not an environmental episode, source, compliance, exposure or health finding. No England-wide current environmental assessment is published because the governed monitoring coverage and freshness gate was not met. No episode was available for corroboration. Cross-source convergence was not applicable to an episode in this run.",
    "publication_kind": "data_coverage_status",
    "scientific_episode_release": "not_applicable_no_screening_events",
    "scientific_episode_release_display": "ASSESSMENT UNAVAILABLE",
    "scientific_finding_social_publication_allowed": false,
    "social_publication_allowed": true,
    "social_publication_mode": "data_coverage_status_only",
    "source_attribution_allowed": false,
    "uk_ready_architecture": true,
    "website_publication_allowed": true
  },
  "schema": "aq26_public_release_contract_v3"
}