{
 "generado": "2026-09-16",
 "volcan": {
  "nombre": "Anak Krakatau",
  "lat": -6.102,
  "lon": 105.423,
  "pais": "Indonesia",
  "estrecho": "Sonda, entre Java y Sumatra"
 },
 "erupcion": {
  "inicio_utc": "2026-09-04T16:20",
  "inicio_local": "2026-09-04 23:20 WIB",
  "fin_utc": "2026-09-06T00:04",
  "duracion_h": 25,
  "columna_km": [
   15,
   20
  ],
  "columna_pies": 50000,
  "alerta": "Nivel III de IV, subido el 2 de julio de 2026",
  "impacto": {
   "aeropuertos_cerrados": 7,
   "vuelos": 3000,
   "pasajeros": 340000,
   "vuelos_injourney": 2300,
   "pasajeros_injourney": 268539,
   "estruendo_km": 700,
   "normalizado": "2026-09-08"
  }
 },
 "so2": {
  "umbral_DU": 26.640367444058697,
  "parche_min_px": 200,
  "previos": [
   "20260902",
   "20260903",
   "20260904"
  ],
  "dias": [
   {
    "fecha": "20260902",
    "km2_bruto": 47815.92190252374,
    "km2": 6695.728696006514,
    "Tg": 0.0005573164538590297,
    "max_DU": 134.48573303222656,
    "r90_km": 128.46108801603776,
    "px": 219,
    "cobertura": 0.8488389423076923
   },
   {
    "fecha": "20260903",
    "km2_bruto": 58241.87544665231,
    "km2": 6694.943430758278,
    "Tg": 0.0008464146521465065,
    "max_DU": 247.20193481445312,
    "r90_km": 128.25776489702503,
    "px": 219,
    "cobertura": 0.8189711538461538
   },
   {
    "fecha": "20260904",
    "km2_bruto": 53478.179187569076,
    "km2": 6359.667784390294,
    "Tg": 0.0007034050019063739,
    "max_DU": 211.2187042236328,
    "r90_km": 114.80158533301922,
    "px": 208,
    "cobertura": 0.87740625
   },
   {
    "fecha": "20260905",
    "km2_bruto": 573852.88786,
    "km2": 532385.0260979688,
    "Tg": 0.5855964822601107,
    "max_DU": 11782.734375,
    "r90_km": 903.45492684511,
    "px": 17442,
    "cobertura": 0.8814543269230769
   },
   {
    "fecha": "20260906",
    "km2_bruto": 1788151.2680766236,
    "km2": 1702765.878772212,
    "Tg": 0.565910396892918,
    "max_DU": 3478.10888671875,
    "r90_km": 1686.3181727692095,
    "px": 56030,
    "cobertura": 0.8677379807692308
   },
   {
    "fecha": "20260907",
    "km2_bruto": 2261916.607316866,
    "km2": 2049580.2038703735,
    "Tg": 0.24682995064480331,
    "max_DU": 983.5131225585938,
    "r90_km": 1802.4780633270784,
    "px": 68632,
    "cobertura": 0.8104206730769231
   },
   {
    "fecha": "20260908",
    "km2_bruto": 2389883.3686443497,
    "km2": 2178549.6092122407,
    "Tg": 0.19878562432656482,
    "max_DU": 207.19947814941406,
    "r90_km": 1771.8463474953628,
    "px": 72618,
    "cobertura": 0.8628990384615385
   }
  ],
  "nulo_km2": 6695.728696006514,
  "nulo_Tg": 0.0008464146521465065,
  "pico_km2": 532385.0260979688,
  "pico_Tg": 0.5855964822601107,
  "pico_fecha": "20260905",
  "razon_km2": 79.51114064933596,
  "razon_Tg": 691.8553226542556,
  "max_km2": 2178549.6092122407,
  "max_km2_fecha": "20260908",
  "veces_chile": 2.881313496185988,
  "r90_nulo_km": 128.46108801603776,
  "r90_ultimo_km": 1771.8463474953628,
  "chile_km2": 756096
 },
 "altura": {
  "supuestos": {
   "por defecto": {
    "km2_qa": 524069.7879459159,
    "Tg_qa": 0.5721822026890607,
    "maxDU_qa": 11782.734419972852,
    "km2": 532321.8334993313,
    "Tg": 0.6330607646459933,
    "maxDU": 66242.6520485738
   },
   "1 km": {
    "km2_qa": 1090055.6899625163,
    "Tg_qa": 1.20988256321581,
    "maxDU_qa": 14191.918153011447,
    "km2": 1095766.1145481374,
    "Tg": 1.2219192604186382,
    "maxDU": 14191.918153011447
   },
   "7 km": {
    "km2_qa": 405742.9440704461,
    "Tg_qa": 0.25361055498736107,
    "maxDU_qa": 2869.2672394475717,
    "km2": 410750.1076104375,
    "Tg": 0.2615364161139259,
    "maxDU": 3318.3615682237064
   },
   "15 km": {
    "km2_qa": 365746.01489225146,
    "Tg_qa": 0.16874218908856245,
    "maxDU_qa": 2300.422797366548,
    "km2": 370533.7228740679,
    "Tg": 0.17570961824660172,
    "maxDU": 2917.0559006506005
   }
  },
  "cimss_Tg": 0.2,
  "archivo": "S5P_OFFL_L2__SO2____20260905T054628_20260905T072758_46093_03_020800.nc",
  "razon_extremos": 6.954196774269473,
  "razon_defecto_15km": 3.6028805421312606,
  "dif_cimss_pct": 12.145190876699145
 },
 "isla": {
  "fechas": [
   {
    "fecha": "20260824",
    "etq": "control",
    "ha": 633.05,
    "nube_en_cuerpo_pct": 58.85475080957271,
    "nube_en_borde_pct": 43.0622009569378,
    "sirve": false
   },
   {
    "fecha": "20260903",
    "etq": "antes",
    "ha": 444.77,
    "nube_en_cuerpo_pct": 35.73082716909863,
    "nube_en_borde_pct": 32.842980492484806,
    "sirve": false
   },
   {
    "fecha": "20260908",
    "etq": "despues",
    "ha": 730.59,
    "nube_en_cuerpo_pct": 76.46149002860702,
    "nube_en_borde_pct": 49.17808219178082,
    "sirve": false
   }
  ],
  "veredicto": "El 8-sep tiene nube sobre el cono o pegada a su costa. La superficie de esa fecha NO es una medición: es un número contaminado. La pregunta del colapso queda abierta hasta el primer radar posterior, que atraviesa nube y ceniza.",
  "umbral_swir2": 0.08,
  "scl_falla": "El SCL que viene con el producto clasifica la isla entera como agua: la roca basáltica fresca es casi tan oscura como el mar."
 },
 "manto": {
  "manto_km2": 2781,
  "encuadre_km2": 5024,
  "manto_pct": 55,
  "umbral_swir2": 0.1,
  "nivel": "L1C",
  "columna_km": [
   14.0,
   10.4
  ],
  "columna_caja": [
   105.3,
   -6.148,
   105.426,
   -6.054
  ],
  "borde_pasada_lon_en_cono": 105.308,
  "prueba_tierra_mar": {
   "3-sep": {
    "Rakata": [
     0.2373,
     0.1313,
     0.0631
    ],
    "mar_este": [
     0.0351,
     0.0291,
     0.0215
    ],
    "mar_sureste": [
     0.0104,
     0.0083,
     0.006
    ]
   },
   "5-sep": {
    "Rakata": [
     0.1494,
     0.183,
     0.2186
    ],
    "mar_este": [
     0.1378,
     0.1736,
     0.2038
    ],
    "mar_sureste": [
     0.1486,
     0.1889,
     0.2232
    ]
   },
   "bandas": [
    "NIR",
    "SWIR1",
    "SWIR2"
   ]
  }
 },
 "penacho": {
  "sensor": "VIIRS / NOAA-20 · NASA Worldview GIBS",
  "fecha": "2026-09-05",
  "caja": [
   99.0,
   -10.0,
   112.0,
   -1.5
  ],
  "penacho_km2": 34221,
  "alcance_km": 295,
  "control_4sep_km2": 0,
  "control_4sep_km": 0,
  "so2_km2_mismo_dia": 532385,
  "razon_so2_visible": 15.6,
  "limite": "medido sobre composición en color real renderizada, no sobre radiancias calibradas"
 },
 "colapso_2018": {
  "fecha": "2018-12-22",
  "muertos": 430,
  "muertos_fuente": "Walter et al. 2019 (Nat. Commun.); cifra oficial BNPB 437",
  "volumen_perdido": "del orden de 0,1 km3 del edificio; cono decapitado (Williams et al. 2019, Geology)",
  "aviso": "sin aviso previo"
 },
 "radar": {
  "ultimo_previo_utc": "2026-09-03T11:22",
  "primer_posterior": "2026-09-15T11:22",
  "proximas_pasadas": [
   "2026-09-10 (track 11:14)",
   "2026-09-11 (track 22:41)",
   "2026-09-15 (track 11:22, misma geometría que el 3-sep)"
  ],
  "nota_html": "y el 15 de septiembre a las 11:22 UTC pasó el primero posterior por la misma órbita. La medición de superficie está en la sección siguiente.",
  "isla": {
   "umbral_db": -15.788167953491211,
   "metodo_umbral": "Otsu sobre 3-sep, aplicado igual a las tres fechas",
   "radio_cierre_px": 20,
   "track": "11:22 UTC",
   "control": "20260822",
   "previo": "20260903",
   "evento": "20260915",
   "fechas": {
    "20260822": {
     "contorno_ha": 316.10976083224404,
     "brillante_ha": 251.59407809333447,
     "mar_db": -22.520837783813477,
     "tierra_db": -13.226737976074219,
     "cumbre_dentro": true
    },
    "20260903": {
     "contorno_ha": 317.363687947613,
     "brillante_ha": 253.6180808962815,
     "mar_db": -19.181730270385742,
     "tierra_db": -13.05225658416748,
     "cumbre_dentro": true
    },
    "20260915": {
     "contorno_ha": 343.56836844777285,
     "brillante_ha": 328.4416689103461,
     "mar_db": -19.515445709228516,
     "tierra_db": -11.817813873291016,
     "cumbre_dentro": true
    }
   },
   "error_metodo_ha": 1.253927115368981,
   "dif_evento_ha": 26.20468050015984,
   "error_metodo_brillante_ha": 2.024002802947024,
   "dif_evento_brillante_ha": 74.8235880140646,
   "sensibilidad": [
    {
     "umbral_db": -16.5,
     "radio_px": 10,
     "20260822": 317.0,
     "20260903": 330.4,
     "20260915": 353.3,
     "control": 13.4,
     "evento": 22.9
    },
    {
     "umbral_db": -16.5,
     "radio_px": 20,
     "20260822": 321.9,
     "20260903": 385.4,
     "20260915": 356.8,
     "control": 63.5,
     "evento": -28.6
    },
    {
     "umbral_db": -16.5,
     "radio_px": 30,
     "20260822": 324.4,
     "20260903": 395.6,
     "20260915": 359.4,
     "control": 71.2,
     "evento": -36.2
    },
    {
     "umbral_db": -15.8,
     "radio_px": 10,
     "20260822": 306.9,
     "20260903": 308.6,
     "20260915": 340.3,
     "control": 1.7,
     "evento": 31.7
    },
    {
     "umbral_db": -15.8,
     "radio_px": 20,
     "20260822": 316.2,
     "20260903": 317.4,
     "20260915": 343.8,
     "control": 1.2,
     "evento": 26.4
    },
    {
     "umbral_db": -15.8,
     "radio_px": 30,
     "20260822": 319.6,
     "20260903": 320.9,
     "20260915": 346.9,
     "control": 1.3,
     "evento": 26.0
    },
    {
     "umbral_db": -15.0,
     "radio_px": 10,
     "20260822": 275.2,
     "20260903": 273.3,
     "20260915": 323.0,
     "control": -1.9,
     "evento": 49.7
    },
    {
     "umbral_db": -15.0,
     "radio_px": 20,
     "20260822": 294.6,
     "20260903": 300.4,
     "20260915": 330.5,
     "control": 5.8,
     "evento": 30.1
    },
    {
     "umbral_db": -15.0,
     "radio_px": 30,
     "20260822": 306.0,
     "20260903": 307.6,
     "20260915": 334.6,
     "control": 1.6,
     "evento": 27.0
    },
    {
     "umbral_db": -14.0,
     "radio_px": 10,
     "20260822": 177.9,
     "20260903": 197.9,
     "20260915": 304.0,
     "control": 20.0,
     "evento": 106.1
    },
    {
     "umbral_db": -14.0,
     "radio_px": 20,
     "20260822": 212.8,
     "20260903": 218.3,
     "20260915": 310.6,
     "control": 5.5,
     "evento": 92.3
    },
    {
     "umbral_db": -14.0,
     "radio_px": 30,
     "20260822": 265.9,
     "20260903": 266.0,
     "20260915": 314.9,
     "control": 0.1,
     "evento": 48.9
    }
   ],
   "veredicto": "El contorno de la isla creció: +26.2 ha (+8 %), contra un error de método de 1.3 ha medido en el par de control."
  },
  "isla_segunda_orbita": {
   "umbral_db": -11.847352027893066,
   "metodo_umbral": "Otsu sobre 30-ago, aplicado igual a las tres fechas",
   "radio_cierre_px": 20,
   "track": "22:41 UTC",
   "control": "20260818",
   "previo": "20260830",
   "evento": "20260911",
   "fechas": {
    "20260818": {
     "contorno_ha": 325.60842435594,
     "brillante_ha": 199.22375561196645,
     "mar_db": -17.827728271484375,
     "tierra_db": -6.767818927764893,
     "cumbre_dentro": true
    },
    "20260830": {
     "contorno_ha": 315.17164237158056,
     "brillante_ha": 205.44386988795802,
     "mar_db": -15.40417194366455,
     "tierra_db": -8.175056457519531,
     "cumbre_dentro": true
    },
    "20260911": {
     "contorno_ha": 321.01635444164214,
     "brillante_ha": 289.4793718030139,
     "mar_db": -14.609526634216309,
     "tierra_db": -8.206783294677734,
     "cumbre_dentro": true
    }
   },
   "error_metodo_ha": 10.436781984359413,
   "dif_evento_ha": 5.844712070061576,
   "error_metodo_brillante_ha": 6.220114275991563,
   "dif_evento_brillante_ha": 84.0355019150559,
   "sensibilidad": [
    {
     "umbral_db": -16.5,
     "radio_px": 10,
     "20260818": 963.9,
     "20260830": 1858.2,
     "20260911": 1891.0,
     "control": 894.3,
     "evento": 32.8
    },
    {
     "umbral_db": -16.5,
     "radio_px": 20,
     "20260818": 1015.5,
     "20260830": 1739.8,
     "20260911": 1740.3,
     "control": 724.3,
     "evento": 0.5
    },
    {
     "umbral_db": -16.5,
     "radio_px": 30,
     "20260818": 963.9,
     "20260830": 1573.2,
     "20260911": 1573.2,
     "control": 609.3,
     "evento": 0.0
    },
    {
     "umbral_db": -15.8,
     "radio_px": 10,
     "20260818": 850.1,
     "20260830": 1818.2,
     "20260911": 1877.3,
     "control": 968.1,
     "evento": 59.1
    },
    {
     "umbral_db": -15.8,
     "radio_px": 20,
     "20260818": 891.7,
     "20260830": 1693.9,
     "20260911": 1728.3,
     "control": 802.2,
     "evento": 34.4
    },
    {
     "umbral_db": -15.8,
     "radio_px": 30,
     "20260818": 864.0,
     "20260830": 1551.3,
     "20260911": 1571.7,
     "control": 687.3,
     "evento": 20.4
    },
    {
     "umbral_db": -15.0,
     "radio_px": 10,
     "20260818": 505.4,
     "20260830": 1203.3,
     "20260911": 1831.8,
     "control": 697.9,
     "evento": 628.5
    },
    {
     "umbral_db": -15.0,
     "radio_px": 20,
     "20260818": 714.4,
     "20260830": 1615.1,
     "20260911": 1696.4,
     "control": 900.7,
     "evento": 81.3
    },
    {
     "umbral_db": -15.0,
     "radio_px": 30,
     "20260818": 783.2,
     "20260830": 1494.9,
     "20260911": 1547.9,
     "control": 711.7,
     "evento": 53.0
    },
    {
     "umbral_db": -14.0,
     "radio_px": 10,
     "20260818": 346.5,
     "20260830": 404.5,
     "20260911": 1322.9,
     "control": 58.0,
     "evento": 918.4
    },
    {
     "umbral_db": -14.0,
     "radio_px": 20,
     "20260818": 372.6,
     "20260830": 598.1,
     "20260911": 1521.7,
     "control": 225.5,
     "evento": 923.6
    },
    {
     "umbral_db": -14.0,
     "radio_px": 30,
     "20260818": 436.8,
     "20260830": 725.1,
     "20260911": 1480.7,
     "control": 288.3,
     "evento": 755.6
    }
   ],
   "veredicto": "El cambio de contorno (+5.8 ha) no supera el error del método (10.4 ha). No se puede afirmar que la isla cambió de tamaño.",
   "nota": "Pasada de tarde (22:41 UTC): mar demasiado brillante para medir costa; confirma sólo el cambio de superficie brillante."
  }
 },
 "fuentes": {
  "s5p": "Copernicus Sentinel-5P (TROPOMI), producto L2 de SO2, versión 02.08.00",
  "s2": "Copernicus Sentinel-2 L2A, órbita relativa R075, 10 m",
  "cimss": "CIMSS/SSEC, Universidad de Wisconsin-Madison, blog satelital, 5-sep-2026",
  "prensa": "Red Geocientífica de Chile, T13, Al Jazeera, CNN, Euronews, 6-8 sep 2026"
 }
}