5/3 10th Volcano Stats

How many active volcanoes are there?The answer to this common question depends upon use of the word "active." At least 20 volcanoes will probably be erupting as you read these words. The number is also dependent on what time scale is included, and if only confirmed eruptions are counted, or uncertain eruptions and the opinions of volcanologists are considered. Because dormant intervals between major eruptions at a single volcano may last hundreds to tens of thousands of years, dwarfing the relatively short historical record in many regions, it is misleading to restrict usage of "active volcano" to recorded human memories: we prefer to add another identifying word (e.g. "historically active" or "Holocene" volcano). The numbers will change as new research is published, new age dates are acquired, or new criteria are applied and volcanoes are reviewed.Here are a few statistics (at last database update on 12 Mar 2021):- Volcanoes erupting now: 45- Volcanoes that erupted during 2021: 49- Volcanoes that erupted during 2020: 67- Volcanoes with confirmed historical eruptions: 560- Volcanoes with confirmed Holocene eruptions: 866- Volcanoes thought to have Holocene eruptions: 1,413Thedefinition of "volcano"is as important in answering the number question as the definition of "active." Usage has varied widely, with "volcano" applied to individual vents, volcanic edifices, or volcanic fields. We have tended toward the broader definition in our compilations, allowing the record of a single large plumbing system to be viewed as a whole, but this approach often requires careful work in field and laboratory to establish a common magmatic link. Perhaps the most honest answer to the number question is that we do not really have an accurate count of the world's volcanoes, but that there are at least a thousand identified magma systems--on land alone--likely to erupt in the future.Note that the figures above do not include most eruptions (and undescribed volcanoes) on the deep sea floor. Estimates of global magma budgets suggest that roughly 75% of the lava reaching Earth's surface does so unnoticed at submarine midocean ridges. Some estimates of young seafloor volcanoes exceed a million.What volcanoes have the most people living nearby?The number of people living in proximity to volcanoes has clear volcanic hazards implications, and population datasets help assess volcanic risk. The LandScan population dataset produced by the Oak Ridge National Laboratory apportions census counts to grid cells based on likelihood coefficients incorporating proximity to roads, slope, land cover, nighttime lights, and other data. TheLandScan 2008data set was applied to the Volcanoes of the World database (for publication inVolcanoes of the World, 3rd ed.) to calculate population densities surrounding Holocene volcanoes at radii of 5, 10, 30, and 100 km. The 10 volcanoes with the greatest population at each of those distance ranges are shown in the tables below.Data also factor population densities at volcanic fields with large numbers of vents over broad areas, oceanic shield volcanoes with large footprints, and large silicic calderas. For volcanic fields, minimum population densities were calculated for those living within a rectangle encompassing the known footprint of the volcanic field or a circle of 20 km (the average radius of database volcanic fields with documented dimensions). Similarly, 20 km minimum radii were used for large oceanic shield volcanoes and large silicic calderas that could erupt from vents in broad areas over their flanks. These data do not account for non-resident visitors to national parks, forests, or other recreational areas in volcanic regions, which form an unknown, but sometimes non-trivial component of persons at risk from volcanic eruptions. Population within 5 kmVolcano Country Population within 5 km Last Eruption Michoacan-GuanajuatoMexico5,783,2871952 CETatun Volcanic GroupTaiwan5,084,149648 CECampi FlegreiItaly2,234,1091538 CEIlopangoEl Salvador2,049,5831880 CEHainan Volcanic FieldChina1,731,2291933 CESan Pablo Volcanic FieldPhilippines1,349,7421350 CEGhegham Volcanic RidgeArmenia1,265,1531900 BCEDieng Volcanic ComplexIndonesia1,092,9292018 CEAuckland Volcanic FieldNew Zealand1,049,1101350 CEBas Dong NaiVietnam991,688UnknownThere have been 101 confirmed eruptions with start dates in 1750 or later that have lasted at least 60 months (5 years or more), from 57 different volcanoes. Continuing eruptions account for 26. The number of Eruption Months is a count of the number of different months from the Start Date to the Stop Date, not taking any uncertainty into account. Eruption Years is the number of full years in eruption calculated from the month total. This does not consider any eruptive pauses shorter than three months; for consistency in the Volcanoes of the World database, renewed eruptions after inactivity lasting more than three months results in the designation of a new eruption. Eruptions are listed below sorted with the longest at the top.Volcano Country Eruption Months Eruption Years Eruption Start Date Eruption Stop DateMax VEIYasurVanuatu29602471774 Jul 2 (in or before) ± 182 days2021 Mar 12 (continuing)3Santa MariaGuatemala1185991922 Jun 222021 Mar 12 (continuing)3DukonoIndonesia1051881933 Aug 132021 Mar 12 (continuing)3StromboliItaly1045871934 Feb 22021 Mar 12 (continuing)2SangayEcuador919771934 Aug 82011 Mar 23AiraJapan730611955 Oct 132016 Aug 223Erta AleEthiopia641531967 Jul 2 (in or before) ± 182 days2020 Dec 40NyiragongoDR Congo598501927 Mar 16 ± 15 days1977 Jan 101ErebusAntarctica579481972 Dec 16 (in or before) ± 15 days2021 Mar 12 (continuing)2ArenalCosta Rica509421968 Jul 292010 Dec 16 (?) ± 15 days3SemeruIndonesia499421967 Aug 312009 Mar 153KilaueaUnited States428361983 Jan 32018 Sep 53VesuviusItaly369311913 Jul 51944 Apr 43VesuviusItaly364301875 Dec 181906 Apr 224LangilaPapua New Guinea332281973 Feb 24 ± 4 days2000 Oct 16 (in or after) ± 15 days3SuwanosejimaJapan330281956 Nov 16 ± 15 days1984 May 16 ± 15 days2ManamPapua New Guinea308261974 Mar 4 (?)1999 Nov 9 (?)3PacayaGuatemala284241965 Jul 41989 Mar 103BaganaPapua New Guinea276231972 Jul 2 ± 182 days1995 Jul 2 (in or after) ± 182 days2SheveluchRussia259221999 Aug 152021 Mar 12 (continuing)4BaganaPapua New Guinea253212000 Feb 28 (in or before)2021 Mar 12 (continuing)2MasayaNicaragua234201965 Oct 10 (?)1985 Apr 16 (?) ± 15 days1FuegoGuatemala230192002 Jan 42021 Mar 12 (continuing)3NyiragongoDR Congo226192002 May 17 (?)2021 Mar 12 (continuing)2SuwanosejimaJapan197162004 Oct 232021 Mar 12 (continuing)2PopocatepetlMexico194162005 Jan 92021 Mar 12 (continuing)2SemeruIndonesia173141950 Jul 231964 Dec 16 ± 15 days2KarymskyRussia173142001 Nov 152016 Apr 13ColimaMexico163141997 Nov 222011 Jun 213SaundersUnited Kingdom162142000 May 132013 Nov 160EtnaItaly161131979 Jul 31992 Dec 16 ± 15 days2Nevados de ChillanChile156131973 Jul 16 ± 15 days1986 Jul 2 ± 182 days2IbuIndonesia155132008 Apr 52021 Mar 12 (continuing)1ReventadorEcuador151132008 Jul 272021 Feb 15 (continuing)2MerapiIndonesia149121972 Oct 61985 Mar 16 ± 15 days2KarymskyRussia149121970 May 111982 Oct 113Ol Doinyo LengaiTanzania142121994 Sep 182006 Jul 16 (?) ± 15 days1VesuviusItaly131111783 Aug 181794 Jul 53BezymiannyRussia130112010 May 21 (?)2021 Mar 8 (continuing)3MerapiIndonesia129111992 Jan 202002 Oct 19 (?)2Ol Doinyo LengaiTanzania128111983 Jan 11993 Sep 242TofuaTonga127112004 Mar 192014 Oct 181AmbrymVanuatu127112008 May 232018 Dec 172VesuviusItaly122101824 Jul 21834 Sep 23PacayaGuatemala122101990 Jan 4 (?)2000 Mar 13TungurahuaEcuador117101999 Oct 52009 Jul 8 ± 7 days3TungurahuaEcuador117101916 Mar 31925 Dec 1 ± 30 days4VesuviusItaly116101770 Feb 151779 Oct 4 (?)3AmbrymVanuatu11091996 Jun 16 (in or before) ± 15 days2005 Aug 16 (in or after) ± 15 days1IzalcoEl Salvador10991948 Nov 41957 Dec 1 ± 30 days3Michoacan-GuanajuatoMexico10891943 Feb 201952 Feb 254PoasCosta Rica10891898 Dec 291907 Dec 31 ± 365 days1GalerasColombia10891974 Jul 2 ± 182 days1983 Jul 2 (?) ± 182 days1Batu TaraIndonesia10692007 Jan 17 (?)2015 Nov 262Whakaari IslandNew Zealand10181986 Feb 1 (?)1994 Jul 283VesuviusItaly10181841 Sep 201850 Feb 162HeardAustralia10082012 Sep 5 ± 4 days2021 Jan 20 (continuing)0SabancayaPeru10081990 May 281998 Sep 16 (?) ± 15 days3Soufriere HillsUnited Kingdom9981995 Jul 182003 Oct 83LascarChile9881959 Nov 16 ± 15 days1968 Jan 31 (in or after)2Soufriere HillsUnited Kingdom9482005 Apr 152013 Feb 53PopocatepetlMexico9281996 Mar 52003 Nov 22 (?)3MarapiIndonesia9181987 Jan 151994 Aug 12 (in or after)2EtnaItaly9082013 Sep 32021 Mar 12 (continuing)2EtnaItaly9081971 Sep 191979 Mar 16 (?) ± 15 days2EtnaItaly8571994 Jun 172001 Jul 173ColimaMexico8471963 Jul 2 ± 182 days1970 Jul 2 ± 182 days1SemeruIndonesia8372014 Apr 1 ± 15 days2021 Mar 12 (continuing)3NW Rota-1United States8072003 Jul 2 (?) ± 182 days2010 Mar 16 (in or after) ± 15 days0Ol Doinyo LengaiTanzania8071960 Mar 16 (in or before) ± 15 days1966 Nov 28 ± 30 days3ManamPapua New Guinea8172014 Jun 292021 Mar 12 (continuing)2St. HelensUnited States7971980 Mar 271986 Oct 28 ± 3 days5Nevado del RuizColombia7662014 Nov 182021 Mar 12 (continuing)2VillarricaChile7562014 Dec 2 ± 7 days2021 Mar 12 (continuing)1SaundersUnited Kingdom7562014 Nov 122021 Feb 19 (continuing)1SuwanosejimaJapan7561990 Apr 16 ± 15 days1996 Jul 142VesuviusItaly7261855 Dec 191861 Dec 313Montagu IslandUnited Kingdom7162001 Oct 1 ± 20 days2007 Sep 201Nevado del RuizColombia7061985 Sep 111991 Jul 133MerapiIndonesia6961953 Mar 21958 Dec 16 ± 15 days2RabaulPapua New Guinea7061995 Nov 282001 Sep 5 ± 4 days2PacayaGuatemala6962015 Jun 7 ± 1 days2021 Mar 12 (continuing)1PoasCosta Rica6961952 Mar 231957 Dec 252KarangetangIndonesia6761983 May 16 ± 15 days1988 Dec 31 (in or after)3EtnaItaly6661935 Jul 71941 Jan 27 (?)3LamingtonPapua New Guinea6661951 Jan 171956 Jul 2 ± 182 days4TofuaTonga6552015 Oct 22021 Mar 12 (continuing)0MasayaNicaragua6552015 Oct 32021 Mar 12 (continuing)1SheveluchRussia6551944 Nov 51950 Apr 62AsamayamaJapan6551909 Jan 291914 Jun 241LangilaPapua New Guinea6552015 Oct 22 (?)2021 Mar 9 (continuing)2SoputanIndonesia6451991 May 221996 Sep 29 (in or after)2EtnaItaly6251959 Oct 171964 Dec 313EtnaItaly6251966 Jan 101971 Mar 16 (?) ± 15 days2Nevados de ChillanChile6252016 Jan 82021 Mar 12 (continuing)2KilaueaUnited States6251969 May 241974 Jul 220ManamPapua New Guinea6252004 Oct 242009 Dec 12 (?)4Whakaari IslandNew Zealand6151976 Dec 181982 Jan 293SheveluchRussia6151990 Jan 101995 Feb 16 ± 15 days3BezymiannyRussia6051965 Mar 91970 Mar 16 ± 15 days3Southern EPR at 8°SUndersea Features6051964 Jul 2 (?) ± 182 days1969 Jul 2 (?) ± 182 days0Scientists use a wide variety of techniques to monitor volcanoes, including seismographic detection of the earthquakes and tremor that almost always precede eruptions, precise measurements of ground deformation that often accompanies the rise of magma, changes in volcanic gas emissions, and changes in gravity and magnetic fields. Although not diagnostic individually, these techniques, when used in combination at well-monitored volcanoes, have resulted in successful predictions. At Pinatubo volcano (Philippines) in 1991, a successful forecast saved thousands of lives. TheUSGS Volcano Hazards Prgramnotes that the key to an accurate short-term eruption forecast is being able to recognize when such monitored data show consistent changes from normal background levels of activity.Monitoring-based forecasts are becoming much more reliable, but they remain imperfect. If scientists are fortunate, precursors to an eruption follow the same course as they followed before previous eruptions. Patterns often change, though, and wholly new behavior is observed. The best forecasts will be based on an integration of geologic history, realtime monitoring, and a deep understanding of the internal plumbing processes of the specific volcano. Even with the best of monitoring and interpretations, reliable forecasts are rarely possible more than a few days in advance of an eruption.Some forecasts of volcanic eruptions are based on eruption recurrence intervals, but these are notoriously unreliable for two reasons: 1) few volcanoes are sufficiently well studied to provide an accurate eruptive history over the many hundreds, or tens of thousands, of years necessary to establish a reliable recurrence interval; and 2) few volcanoes maintain the same behavior for long (more often than not, as soon as a repetitive pattern becomes apparent, the volcano changes behavior).Volcano observatories make forecasts with great caution as they can have huge impacts on the affected populations, in some cases forcing people to leave behind homes, farms, and livestock. Inaccurate forecasts can lead to unnecessary obligation of scarce resources and undermine residents' confidence in future forecasts.Reliable forecasts, however, can be made by volcano observatory staff, who have the experience to interpret their monitoring that detects eruption precursors. Most nations with volcanoes have tasked an established observatory, run by the government or by a university, to provide eruption forecasts to the public. All of these observatories are members of the World Organization of Volcano Observatories (WOVO). What volcano has the most people living nearby? What is the population? What people have the least amount of people living by? What is the population? What is the oldest year of the eruption of a volcano?What is the most recent year? Because dormant intervals between major eruptions at a single volcano may last hundreds to tens of thousands of years, dwarfing the relatively short historical record in many regions, it is misleading to restrict usage of "active volcano" to recorded human memories: we prefer to add another identifying word (e.g. "historically active" or "Holocene" volcano). - Volcanoes erupting now: 45- Volcanoes that erupted during 2021: 49- Volcanoes that erupted during 2020: 67- Volcanoes with confirmed historical eruptions: 560- Volcanoes with confirmed Holocene eruptions: 866- Volcanoes thought to have Holocene eruptions: 1,413 Scientists use a wide variety of techniques to monitor volcanoes, including seismographic detection of the earthquakes and tremor that almost always precede eruptions, precise measurements of ground deformation that often accompanies the rise of magma, changes in volcanic gas emissions, and changes in gravity and magnetic fields.