{
  "schema_version": 1,
  "generated_at_utc": "2026-05-16T04:14:42Z",
  "source_registry": "Data/Tiles/ground_zero_tiles.json",
  "generation_rule": "Only tiles with real source status and explicit timezone data are emitted.",
  "tiles": [
    {
      "tile_id": "gz_us_ca_pacifica_utm10n_e544_n4160",
      "center_latitude": 37.5925,
      "center_longitude": -122.4995,
      "time_zone_id": "America/Los_Angeles",
      "standard_utc_offset_hours": -8.0,
      "daylight_utc_offset_hours": -7.0,
      "solar_model": "NOAA approximate sunrise/sunset",
      "sample_solar_hours": {
        "march_equinox": {
          "sunrise_hour": 7.231,
          "sunset_hour": 19.364,
          "solar_noon_hour": 13.298,
          "day_length_hours": 12.133
        },
        "june_solstice": {
          "sunrise_hour": 5.807,
          "sunset_hour": 20.571,
          "solar_noon_hour": 13.189,
          "day_length_hours": 14.764
        },
        "september_equinox": {
          "sunrise_hour": 6.956,
          "sunset_hour": 19.122,
          "solar_noon_hour": 13.039,
          "day_length_hours": 12.166
        },
        "december_solstice": {
          "sunrise_hour": 8.348,
          "sunset_hour": 17.912,
          "solar_noon_hour": 13.13,
          "day_length_hours": 9.564
        }
      }
    }
  ]
}