Annual review · USGS ComCat
Earthquakes in 2011
In 2011, USGS catalogued 15,808 M4+ earthquakes worldwide, including 207 significant M6+ events.
15,808 magnitude-4-and-above earthquakes were catalogued worldwide in 2011, including 207 significant M6+ events. The strongest reached M9.1.
- 15,808
- M4+ events
- 207
- Significant M6+
- M9.1
- Strongest
- 52 km
- Avg depth
The year in one line
2011 logged 15,808 catalogued M4+ earthquakes worldwide, 207 of them major M6+ events, topping out at magnitude 9.1.
- 15,808
- M4+ events worldwide
- 207
- major M6+ events
- M9.1
- strongest of the year
- 52 km
- average hypocentral depth
Major-event activity peaked in Mar with 73 M6+ events, aftershock sequences can drive month-to-month spikes for over a year after a megathrust.
Magnitude breakdown - 2011
How 2011's 15,808 catalogued M4+ earthquakes split across the magnitude scale
- M4.0–4.9
13,112 M4-class events
13,112
- M5.0–5.9 2,489
2,489 M5-class events
2,489
- M6.0–6.9 187
187 M6-class events
187
- M7.0–7.9 19
19 M7-class events
19
- M8.0+ 1
1 M8+ events
1
What this shows As in every year, the catalog is dominated by moderate M4–5 events; the rare M6+ band - 207 events in 2011 - is where damaging shaking lives.
Major (M6+) events by month
Count of significant (M6+) earthquakes catalogued in each month of 2011.
Jan
14
Feb
13
Mar
73
Apr
14
May
5
Jun
11
Jul
19
Aug
13
Sep
15
Oct
10
Nov
12
Dec
8
Significant earthquakes in 2011 (207)
Every catalogued M6+ earthquake recorded during 2011, strongest impact first.
| Mag | Location | Depth | Date |
|---|---|---|---|
| 9.1 | 2011 Great Tohoku Earthquake, Japan | 29.0 km | Mar 11, 2011 |
| 7.9 | 47 km E of ?arai, Japan | 42.6 km | Mar 11, 2011 |
| 7.7 | 272 km ESE of Kamaishi, Japan | 18.6 km | Mar 11, 2011 |
| 7.6 | Kermadec Islands region | 17.0 km | Jul 6, 2011 |
| 7.4 | Kermadec Islands region | 33.0 km | Oct 21, 2011 |
| 7.3 | 120 km SE of ?funato, Japan | 32.0 km | Mar 9, 2011 |
| 7.3 | Fox Islands, Aleutian Islands, Alaska | 52.0 km | Jun 24, 2011 |
| 7.3 | Fiji region | 644.6 km | Sep 15, 2011 |
| 7.2 | 42 km NNW of Carahue, Chile | 24.0 km | Jan 2, 2011 |
| 7.2 | 46 km WSW of Dalbandin, Pakistan | 68.0 km | Jan 18, 2011 |
| 7.2 | 71 km SSW of Port-Vila, Vanuatu | 32.0 km | Aug 20, 2011 |
| 7.1 | 29 km ESE of Ishinomaki, Japan | 42.0 km | Apr 7, 2011 |
| 7.1 | 64 km S of Port-Vila, Vanuatu | 28.0 km | Aug 20, 2011 |
| 7.1 | 27 km NNE of Van, Turkey | 18.0 km | Oct 23, 2011 |
| 7.1 | 25 km SSE of Wau, Papua New Guinea | 135.0 km | Dec 14, 2011 |
| 7.0 | 26 km NNE of El Hoyo, Argentina | 576.8 km | Jan 1, 2011 |
| 7.0 | 118 km NNE of Tadine, New Caledonia | 9.0 km | Jan 13, 2011 |
| 7.0 | 177 km ESE of Ishinomaki, Japan | 23.0 km | Jul 10, 2011 |
| 7.0 | 64 km ESE of Contamana, Peru | 147.0 km | Aug 24, 2011 |
| 7.0 | 133 km SSE of Isangel, Vanuatu | 185.1 km | Sep 3, 2011 |
| 6.9 | 21 km N of Tomé, Chile | 26.0 km | Feb 11, 2011 |
| 6.9 | 27 km NNW of Tachilek, Myanmar | 8.0 km | Mar 24, 2011 |
| 6.9 | 236 km N of Baukau, Timor Leste | 469.8 km | Aug 30, 2011 |
| 6.9 | 170 km E of Atka, Alaska | 32.0 km | Sep 2, 2011 |
| 6.9 | 43 km NW of Mangan, India | 50.0 km | Sep 18, 2011 |
| 6.9 | 39 km SW of Santiago, Peru | 24.0 km | Oct 28, 2011 |
| 6.9 | 238 km WNW of Naha, Japan | 224.9 km | Nov 8, 2011 |
| 6.8 | 79 km W of Kirakira, Solomon Islands | 79.0 km | Apr 23, 2011 |
| 6.8 | 124 km NE of Wé, New Caledonia | 11.0 km | May 10, 2011 |
| 6.7 | 38 km W of Constitución, Chile | 21.0 km | Feb 14, 2011 |
| 6.7 | 134 km ESE of Kamaishi, Japan | 2.8 km | Mar 11, 2011 |
| 6.7 | 278 km SSW of Kawalu, Indonesia | 14.0 km | Apr 3, 2011 |
| 6.7 | 41 km NNE of Miyako, Japan | 33.0 km | Jun 22, 2011 |
| 6.7 | south of the Fiji Islands | 532.0 km | Jul 29, 2011 |
| 6.7 | 20 km WNW of Añatuya, Argentina | 578.9 km | Sep 2, 2011 |
| 6.7 | 68 km WSW of Kabanjahe, Indonesia | 91.0 km | Sep 5, 2011 |
| 6.7 | 99 km NE of Miyako, Japan | 30.0 km | Sep 16, 2011 |
| 6.6 | 250 km SSE of Tabiauan, Philippines | 525.0 km | Feb 10, 2011 |
| 6.6 | 133 km ENE of Hasaki, Japan | 16.0 km | Mar 11, 2011 |
| 6.6 | 50 km ESE of ?tsuchi, Japan | 25.7 km | Mar 11, 2011 |
| 6.6 | 7 km SW of Helio García Alfaro, Mexico | 166.2 km | Apr 7, 2011 |
| 6.6 | 17 km SSW of Ishikawa, Japan | 11.0 km | Apr 11, 2011 |
| 6.6 | south of the Kermadec Islands | 86.0 km | Apr 18, 2011 |
| 6.6 | 103 km NE of Angoram, Papua New Guinea | 10.0 km | Jul 31, 2011 |
| 6.6 | 62 km SSW of Trinidad, Bolivia | 549.9 km | Nov 22, 2011 |
| 6.6 | 45 km NNE of Saryg-Sep, Russia | 15.0 km | Dec 27, 2011 |
| 6.5 | 110 km WNW of Isangel, Vanuatu | 22.0 km | Jan 9, 2011 |
| 6.5 | 235 km SSE of Tabiauan, Philippines | 523.2 km | Feb 10, 2011 |
| 6.5 | south of the Fiji Islands | 558.1 km | Feb 21, 2011 |
| 6.5 | South Sandwich Islands region | 87.7 km | Mar 6, 2011 |
| 6.5 | 128 km SE of ?funato, Japan | 15.0 km | Mar 9, 2011 |
| 6.5 | 178 km NNE of Gili Air, Indonesia | 510.6 km | Mar 10, 2011 |
| 6.5 | 115 km ENE of Hasaki, Japan | 49.3 km | Mar 11, 2011 |
| 6.5 | 81 km NE of Hasaki, Japan | 6.8 km | Mar 11, 2011 |
| 6.5 | 146 km E of Namie, Japan | 20.0 km | Mar 12, 2011 |
| 6.5 | 65 km SSW of Port-Vila, Vanuatu | 35.0 km | Aug 20, 2011 |
| 6.5 | 4 km ESE of Finschhafen, Papua New Guinea | 37.0 km | Oct 14, 2011 |
| 6.5 | 6 km SSW of Nuevo Balsas, Mexico | 59.0 km | Dec 11, 2011 |
| 6.4 | Bonin Islands, Japan region | 512.0 km | Jan 12, 2011 |
| 6.4 | 98 km SSW of Panguna, Papua New Guinea | 415.0 km | Feb 7, 2011 |
| 6.4 | 35 km NE of Kandrian, Papua New Guinea | 29.0 km | Mar 9, 2011 |
| 6.4 | 208 km E of Namie, Japan | 35.0 km | Mar 11, 2011 |
| 6.4 | 108 km ESE of Kitaibaraki, Japan | 32.3 km | Mar 11, 2011 |
| 6.4 | 267 km E of Namie, Japan | 11.0 km | Mar 22, 2011 |
| 6.4 | 130 km E of Miyako, Japan | 13.0 km | Mar 22, 2011 |
| 6.4 | 227 km ENE of Levuka, Fiji | 551.7 km | Apr 3, 2011 |
| 6.4 | 120 km WNW of Panguna, Papua New Guinea | 40.0 km | May 15, 2011 |
| 6.4 | west of Macquarie Island | 3.0 km | Jun 5, 2011 |
| 6.4 | 108 km ESE of Kimbe, Papua New Guinea | 16.0 km | Jun 16, 2011 |
| 6.4 | 110 km NE of Calama, Chile | 128.0 km | Jun 20, 2011 |
| 6.4 | 33 km WSW of Cayhagan, Philippines | 19.0 km | Jul 11, 2011 |
| 6.4 | South Sandwich Islands region | 84.0 km | Sep 3, 2011 |
| 6.4 | 66 km SW of Vernon, Canada | 22.0 km | Sep 9, 2011 |
| 6.4 | 172 km WNW of Hihifo, Tonga | 10.0 km | Sep 22, 2011 |
| 6.3 | 68 km ESE of Palca, Peru | 118.0 km | Mar 6, 2011 |
| 6.3 | 126 km W of Kirakira, Solomon Islands | 22.0 km | Mar 7, 2011 |
| 6.3 | 30 km NNE of Namie, Japan | 32.3 km | Mar 11, 2011 |
| 6.3 | 103 km E of Namie, Japan | 50.7 km | Mar 11, 2011 |
| 6.3 | 47 km SE of Kamaishi, Japan | 42.7 km | Mar 11, 2011 |
| 6.3 | 221 km SE of ?funato, Japan | 35.0 km | Mar 11, 2011 |
| 6.3 | off the east coast of Honshu, Japan | 35.9 km | Mar 11, 2011 |
| 6.3 | near the east coast of Honshu, Japan | 24.7 km | Mar 11, 2011 |
| 6.3 | 49 km ESE of Kamaishi, Japan | 45.4 km | Mar 11, 2011 |
| 6.3 | 92 km ENE of Hasaki, Japan | 21.0 km | Mar 11, 2011 |
| 6.3 | 254 km SSE of Alo, Wallis and Futuna | 15.5 km | Mar 31, 2011 |
| 6.3 | 4 km NW of Lebu, Chile | 21.0 km | Jun 1, 2011 |
| 6.3 | 193 km WNW of Tobelo, Indonesia | 61.1 km | Jun 13, 2011 |
| 6.3 | 146 km SSE of Biak, Indonesia | 17.0 km | Jun 26, 2011 |
| 6.3 | 21 km SSE of ?funato, Japan | 41.0 km | Jul 23, 2011 |
| 6.3 | 43 km NE of Namie, Japan | 40.0 km | Jul 24, 2011 |
| 6.3 | 70 km SSW of Kavieng, Papua New Guinea | 10.0 km | Jul 25, 2011 |
| 6.3 | 13 km SSE of Iwaki, Japan | 38.0 km | Jul 30, 2011 |
| 6.3 | Revilla Gigedo Islands region | 10.0 km | Nov 1, 2011 |
| 6.3 | 199 km SSW of Ternate, Indonesia | 17.0 km | Nov 14, 2011 |
| 6.2 | 119 km SSE of Bam, Iran | 10.0 km | Jan 27, 2011 |
| 6.2 | 75 km E of Olonkinbyen, Svalbard and Jan Mayen | 15.0 km | Jan 29, 2011 |
| 6.2 | 62 km E of W?ngjing, India | 85.0 km | Feb 4, 2011 |
| 6.2 | 110 km ESE of Ishinomaki, Japan | 40.6 km | Mar 11, 2011 |
| 6.2 | 261 km ESE of ?funato, Japan | 25.4 km | Mar 11, 2011 |
| 6.2 | 61 km ESE of Namie, Japan | 40.1 km | Mar 11, 2011 |
| 6.2 | 128 km SE of ?funato, Japan | 51.7 km | Mar 11, 2011 |
| 6.2 | 45 km SE of Kamaishi, Japan | 56.3 km | Mar 11, 2011 |
| 6.2 | 134 km ESE of Ishinomaki, Japan | 11.7 km | Mar 11, 2011 |
| 6.2 | 70 km ESE of Kitaibaraki, Japan | 39.6 km | Mar 11, 2011 |
| 6.2 | 13 km E of Arai, Japan | 9.3 km | Mar 11, 2011 |
| 6.2 | 88 km WNW of Noshiro, Japan | 10.0 km | Mar 11, 2011 |
| 6.2 | 72 km NW of Port-Vila, Vanuatu | 17.0 km | Mar 17, 2011 |
| 6.2 | 57 km NNE of Miyako, Japan | 29.0 km | Mar 17, 2011 |
| 6.2 | 36 km SSE of ?funato, Japan | 39.0 km | Mar 25, 2011 |
| 6.2 | 62 km E of Ishinomaki, Japan | 19.0 km | Mar 27, 2011 |
| 6.2 | 23 km SE of T?gane, Japan | 15.0 km | Apr 11, 2011 |
| 6.2 | 6 km WNW of T?gane, Japan | 43.0 km | Apr 21, 2011 |
| 6.2 | 271 km SSE of Alo, Wallis and Futuna | 407.9 km | Aug 19, 2011 |
| 6.2 | 61 km ENE of Namie, Japan | 47.0 km | Aug 19, 2011 |
| 6.2 | 77 km SW of Port-Vila, Vanuatu | 13.0 km | Aug 24, 2011 |
| 6.2 | 75 km NNE of Hihifo, Tonga | 37.0 km | Sep 5, 2011 |
| 6.2 | 53 km SSE of Shizunai-furukawach?, Japan | 38.0 km | Nov 24, 2011 |
| 6.2 | South Sandwich Islands region | 116.0 km | Dec 11, 2011 |
| 6.1 | southeast of the Loyalty Islands | 112.2 km | Jan 5, 2011 |
| 6.1 | 124 km WNW of Isangel, Vanuatu | 18.0 km | Jan 9, 2011 |
| 6.1 | 58 km ESE of Sinabang, Indonesia | 23.0 km | Jan 26, 2011 |
| 6.1 | 13 km SSE of Chiguayante, Chile | 16.0 km | Feb 12, 2011 |
| 6.1 | 56 km WNW of Haveluloto, Tonga | 85.0 km | Feb 12, 2011 |
| 6.1 | 146 km SSE of Poso, Indonesia | 16.2 km | Feb 15, 2011 |
| 6.1 | 41 km SSW of Ust’-Kamchatsk Staryy, Russia | 33.0 km | Feb 20, 2011 |
| 6.1 | 6 km SE of Christchurch, New Zealand | 5.9 km | Feb 21, 2011 |
| 6.1 | 260 km ESE of ?funato, Japan | 40.6 km | Mar 11, 2011 |
| 6.1 | 284 km ESE of Ishinomaki, Japan | 47.3 km | Mar 11, 2011 |
| 6.1 | 275 km ESE of Kamaishi, Japan | 39.5 km | Mar 11, 2011 |
| 6.1 | 87 km ESE of Iwaki, Japan | 28.4 km | Mar 11, 2011 |
| 6.1 | off the east coast of Honshu, Japan | 41.0 km | Mar 11, 2011 |
| 6.1 | 178 km E of Namie, Japan | 17.0 km | Mar 11, 2011 |
| 6.1 | 72 km ESE of Kamaishi, Japan | 17.4 km | Mar 11, 2011 |
| 6.1 | 29 km SSE of Namie, Japan | 38.0 km | Mar 12, 2011 |
| 6.1 | 55 km SE of Ishinomaki, Japan | 15.0 km | Mar 12, 2011 |
| 6.1 | 72 km E of Hasaki, Japan | 8.0 km | Mar 13, 2011 |
| 6.1 | 138 km ENE of Miyako, Japan | 18.0 km | Mar 15, 2011 |
| 6.1 | 72 km ESE of Namie, Japan | 31.0 km | Mar 22, 2011 |
| 6.1 | 114 km E of Namie, Japan | 15.0 km | Mar 29, 2011 |
| 6.1 | 47 km NE of Katabu, Indonesia | 8.0 km | Apr 24, 2011 |
| 6.1 | 143 km SSE of Punta de Burica, Panama | 12.0 km | Apr 30, 2011 |
| 6.1 | 31 km ESE of Namie, Japan | 35.0 km | May 13, 2011 |
| 6.1 | central Mid-Atlantic Ridge | 10.0 km | May 15, 2011 |
| 6.1 | 258 km E of Namie, Japan | 14.0 km | Jun 3, 2011 |
| 6.1 | 26 km SSE of Lata, Solomon Islands | 72.1 km | Jun 24, 2011 |
| 6.1 | South Sandwich Islands region | 10.0 km | Jul 15, 2011 |
| 6.1 | 72 km ESE of King Cove, Alaska | 36.0 km | Jul 16, 2011 |
| 6.1 | 16 km NNE of Aydarken, Kyrgyzstan | 20.0 km | Jul 19, 2011 |
| 6.1 | Vanuatu region | 10.0 km | Jul 31, 2011 |
| 6.1 | 227 km SSW of Severo-Kuril’sk, Russia | 36.0 km | Aug 4, 2011 |
| 6.1 | 151 km NW of Amahai, Indonesia | 26.0 km | Aug 16, 2011 |
| 6.1 | 258 km ESE of Namie, Japan | 9.0 km | Aug 17, 2011 |
| 6.1 | 163 km SW of Bandar Lampung, Indonesia | 29.0 km | Aug 22, 2011 |
| 6.1 | east of the North Island of New Zealand | 10.0 km | Sep 15, 2011 |
| 6.1 | 68 km E of ?arai, Japan | 28.0 km | Sep 15, 2011 |
| 6.1 | south of the Kermadec Islands | 36.0 km | Oct 7, 2011 |
| 6.1 | 88 km SW of Jimbaran, Indonesia | 39.0 km | Oct 13, 2011 |
| 6.1 | 102 km ESE of Kimbe, Papua New Guinea | 26.0 km | Oct 18, 2011 |
| 6.1 | 16 km NE of Asahikawa, Japan | 187.0 km | Oct 21, 2011 |
| 6.1 | Pacific-Antarctic Ridge | 10.0 km | Nov 2, 2011 |
| 6.1 | 35 km ESE of Namie, Japan | 34.0 km | Nov 23, 2011 |
| 6.1 | 205 km SE of Kokopo, Papua New Guinea | 25.0 km | Nov 28, 2011 |
| 6.1 | 76 km NNW of Vallenar, Chile | 20.0 km | Dec 7, 2011 |
| 6.0 | 129 km SSW of Pagar Alam, Indonesia | 36.0 km | Jan 17, 2011 |
| 6.0 | 106 km WNW of Murghob, Tajikistan | 110.0 km | Jan 24, 2011 |
| 6.0 | 101 km SSW of Vaini, Tonga | 76.0 km | Jan 31, 2011 |
| 6.0 | 9 km NNW of Talcahuano, Chile | 17.0 km | Feb 13, 2011 |
| 6.0 | Easter Island region | 10.0 km | Mar 1, 2011 |
| 6.0 | 99 km E of Ishinomaki, Japan | 22.0 km | Mar 9, 2011 |
| 6.0 | 114 km SE of ?funato, Japan | 23.0 km | Mar 9, 2011 |
| 6.0 | 4 km ESE of Hasaki, Japan | 47.5 km | Mar 11, 2011 |
| 6.0 | 17 km ESE of Namie, Japan | 49.2 km | Mar 11, 2011 |
| 6.0 | 126 km ESE of Ishinomaki, Japan | 42.8 km | Mar 11, 2011 |
| 6.0 | 15 km E of Namie, Japan | 37.3 km | Mar 11, 2011 |
| 6.0 | 94 km ESE of Yamada, Japan | 27.6 km | Mar 11, 2011 |
| 6.0 | 76 km ESE of Yamada, Japan | 26.5 km | Mar 11, 2011 |
| 6.0 | 108 km ESE of Takahagi, Japan | 52.8 km | Mar 11, 2011 |
| 6.0 | 80 km E of Yamada, Japan | 27.1 km | Mar 11, 2011 |
| 6.0 | 123 km SE of Ishinomaki, Japan | 14.0 km | Mar 14, 2011 |
| 6.0 | 109 km E of Namie, Japan | 28.0 km | Mar 15, 2011 |
| 6.0 | 6 km NNW of Fujinomiya, Japan | 9.0 km | Mar 15, 2011 |
| 6.0 | 43 km NNE of Namuac, Philippines | 27.0 km | Mar 20, 2011 |
| 6.0 | 146 km ENE of Labasa, Fiji | 6.0 km | Mar 26, 2011 |
| 6.0 | 18 km SSE of ?funato, Japan | 42.0 km | Mar 31, 2011 |
| 6.0 | 42 km NW of Fry, Greece | 59.9 km | Apr 1, 2011 |
| 6.0 | 108 km SW of Singkil, Indonesia | 20.0 km | Apr 6, 2011 |
| 6.0 | 120 km E of Yamada, Japan | 22.0 km | Apr 13, 2011 |
| 6.0 | 224 km SE of Kamaishi, Japan | 11.0 km | May 5, 2011 |
| 6.0 | 87 km SSW of Lata, Solomon Islands | 14.0 km | Jun 21, 2011 |
| 6.0 | Kermadec Islands, New Zealand | 14.0 km | Jul 9, 2011 |
| 6.0 | Kermadec Islands, New Zealand | 15.2 km | Jul 9, 2011 |
| 6.0 | 32 km SW of San Antonio, Chile | 20.0 km | Jul 16, 2011 |
| 6.0 | 16 km NE of Kirakira, Solomon Islands | 21.0 km | Jul 20, 2011 |
| 6.0 | Balleny Islands region | 10.0 km | Jul 21, 2011 |
| 6.0 | 73 km SW of Topolobampo, Mexico | 12.0 km | Jul 26, 2011 |
| 6.0 | 221 km ENE of Georgetown, Saint Helena | 10.0 km | Aug 10, 2011 |
| 6.0 | 193 km NNW of Sola, Vanuatu | 41.0 km | Sep 1, 2011 |
| 6.0 | 32 km NNW of Attu Station, Alaska | 15.0 km | Sep 14, 2011 |
| 6.0 | 8 km ESE of Takhtamygda, Russia | 12.0 km | Oct 14, 2011 |
| 6.0 | 122 km E of Levuka, Fiji | 602.9 km | Oct 27, 2011 |
| 6.0 | 7 km NNE of Belén, Nicaragua | 177.0 km | Nov 7, 2011 |
| 6.0 | southern East Pacific Rise | 10.0 km | Nov 11, 2011 |
| 6.0 | 87 km NW of Salinas, Ecuador | 26.6 km | Nov 17, 2011 |
| 6.0 | 97 km W of Palauig, Philippines | 9.0 km | Nov 30, 2011 |
| 6.0 | 55 km S of Gorontalo, Indonesia | 161.0 km | Dec 13, 2011 |
| 6.0 | south of the Kermadec Islands | 32.0 km | Dec 15, 2011 |
| 6.0 | 27 km SSW of Hihifo, Tonga | 90.0 km | Dec 26, 2011 |
Understand the data
Frequently asked questions
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About this data
Every figure on this page is computed directly from the USGS Comprehensive Earthquake Catalog (ComCat), the public-domain record maintained by the USGS Earthquake Hazards Program. The worldwide catalog covers magnitude-4.0-and-above events from 2005 onward, the period over which the global seismograph network reliably detects and locates earthquakes everywhere. Magnitudes use the moment-magnitude scale (Mw), the modern standard that supersedes the older Richter scale; because the scale is logarithmic, each whole step up represents roughly thirty-two times more energy released. Depth is measured in kilometres from the surface, and shallow earthquakes generally produce stronger surface shaking than deep ones of the same magnitude. Annual counts reflect what instruments recorded, not every tremor that occurred; the current calendar year is always partial and will keep rising as the USGS adds and revises events, so it should never be compared directly against completed years.
Source: USGS ComCat, verify with USGS → · See our methodology for the full pipeline.
Disclaimer: PlainQuake is an informational reference for informational purposes only, not an emergency or early-warning service, and not professional engineering or safety advice. For official alerts and guidance, consult the USGS and your local emergency authorities. See our full disclaimer.