Metp) Met Operations Group (Mog) International Airways Volcano Watch (Iavw
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METP MOG/8 -SN/01 06/11/18 MET PANEL (METP) MET OPERATIONS GROUP (MOG) INTERNATIONAL AIRWAYS VOLCANO WATCH (IAVW) EIGHTH MEETING Wellington, New Zealand, 12 to 14 November 2018 Agenda Item 6: 6.1.: Agenda Item VAAC Darwin Activity report (Presented by Tristan King) SUMMARY This paper presents an IAVW Management Report for the VAAC Darwin areas of responsibility covering the period 1 July 2017 – 16 Oct 2018. 1. INTRODUCTION 1.1 The Volcanic Ash Advisory Centre (VAAC) Darwin is responsible for monitoring the area from the Andaman Islands (India) eastwards to the Solomon Islands including the volcanically active Indonesian archipelago, Papua New Guinea and the southern Philippines. More than 150 active volcanoes lie within the area, some of which have given rise to the largest eruptions in human history. Areas within the region can have poor communications, limited infrastructure and ability to monitor volcanic activity. A large part of the region is characterised by moist tropical convection that makes remote sensing difficult for much of the year. (17 pages) METP WG-MOG/8 SN 17 METP WG-MOG/8-SN 17 - 2 - 2. DISCUSSION 2.1 Issuance of Advisories VAAC Period of reporting Total number of Advisories High Impact Events* Darwin 01 Jul 2017 - 16 Oct 2018 3,855 Agung 25 November 27 June Sinabung 19 February 06 April Merapi 11 May 01 June Manam 25 August 23 September 5 October Soputan 3 October Salak 10 October * Discernible or Visible ash that is impacting or expected to impact aircraft cruising levels, international aerodromes, is of high media interest, or is deemed to be significant to aviation operations by a VAAC. 2.1.1 A total of 2696 advisories were issued by VAAC Darwin (610 less 16/17 FY) and 1159 advisories have been issued for the 18/19 FY up to the 16th October 2018. 2.2 Key Performance Indicators for VAAC Darwin: For the period 1 July 2017 – 16 Oct 2018 VAAC Darwin Initial Advisories issued in time (within 20mins on 100% 95% of occasions) Standard Advisories issued in time (within 75mins 100% on 95% of occasions) Advisories issued by next due time N/A Figure 1 shows the VAAC Darwin's progression towards the KPI. 2.2.1 Figure 2 shows the number of advisories issued by VAAC Darwin (reported by volcano) during this period. There have been a variety of ash generating eruptions throughout the region from - 3 - METP MOG 8/SN 17 1st July 2017 to 16th October 2018 including explosive, short lived eruptions at Sinabung (393 advisories) and Merapi (30 advisories) on the Indonesian Islands of Sumatra and Java respectively. Several longer lived, sustained eruptions were observed with Ulawun (75 advisories) and Langila (119 advisories) on the Island of New Britain and Bagana (129 advisories) Bougainville leading to the most advisories. Dukono in northern Halmahera, Indonesia again erupted almost continually throughout the year with 1921 advisories issued. Mt Krakatau or Anak Krakatau between the Indonesian Islands of Sumatra and Java has become more active with observed lava fountaining and intermittent eruptions since June (260 advisories). Mt Agung on the Indonesian island of Bali had semi-continuous eruption throughout June to August with 440 advisories issued. Manam in Papua New Guinea has provided short-lived eruptions which have been more difficult to detect as well as a few unconfirmed eruptions (100 advisories). Mt Soputan, which last erupted in 2016, erupted recently with a sustained plume for multiple days with 17 advisories issued. Of note is the first eruption of Kadovar (PNG) in recorded history with 133 advisories issued. Mt Salak provided a difficult situation with the rapid generation of a cloud which was later determined to be a thunderstorm so a false alarm (5 advisories). Figure 2 features the total number of advisories issued by VAAC Darwin since 1993. 2500 2000 1921 1500 1000 440 500 393 260 129 133 119 100 78 13 48 3 3 29 3 14 30 5 30 51 17 7 0 Figure 2 - Advisories by volcano for the VAAC Darwin (blue) and areas of responsibility {1st July 2017 until 16th October 2018). VAAC Darwin issuance of VAA in VAAC Tokyo's area in red. METP WG-MOG/8-SN 17 - 4 - Number of Volcanic Ash Advisories - 1993/94 to present 4000 3500 3000 2500 2000 1500 1000 500 Number of Volcanic Ash Advisories Advisories AshVolcanic of Number 0 94/95 97/98 99/00 00/01 02/03 05/06 08/09 11/12 14/15 16/17 17/18 93/94 95/96 96/97 98/99 01/02 03/04 04/05 06/07 07/08 09/10 10/11 12/13 13/14 15/16 18/19* Financial Year Figure 3 - VAAC Darwin: Number of advisories 1993/94 - 2018/19 (blue) and trend line (black). 3. HIGH IMPACT ERUPTIONS 3.1 Agung, Bali, Indonesia – 25 November (2017) and 27 June (2018) 3.1.1 Between 10 June and 27 July 2018, there were 36 distinct eruptive events at Agung requiring the issuance of Volcanic Ash Advisories (VAAs). This prolonged period of unrest at Agung was characterised by frequent discrete low-level eruptions punctuated by occasional high-level and/or continuous eruptions. During the event, both the mode and median ash column heights were FL150 (15,000FT above mean sea level). A total of 236 VAAs were issued during this eruptive campaign. Of the 36 distinct events (defined as such by the issuance of a final VAA), two stand out as the major events of the campaign: (1) a continuous emission commencing on 28 June 0325Z and concluding 30 June 1115Z with 39 VAAs issued and a maximum ash height of FL230, and (2) commencing 2 July 2018 1335Z and concluding 3 July 1445Z with 15 VAAs issued and a maximum ash height of FL300. At operationally critical times, hourly advisories were produced by VAAC Darwin at the request of Airlines 3.2 Merapi, Java, Indonesia – 11 May and 01 June 2018. 3.2.1 Activity at Merapi can be summarised by two distinct high impact events. The first being May 11 where an explosive eruption to FL500 was observed. The volcanic ash dispersed in numerous directions making the forecast complex however the ash was clearly discernible via satellite imagery - 5 - METP MOG 8/SN 17 due to the lack of meteorological cloud following the eruption. The volcanic ash rapidly weakened as it approached Melbourne FIR before dropping below discernible levels with the event lasting approximately 17 hours. Notably, a large amount of supplementary information was received from CVGHM through the instant messaging platform which help to support the VAAC forecasters evidence-based assessment process. 3.3 Sinabung, Sumatra, Indonesia – 19 February and 6 April 2018 3.3.1 Hotspot activity had been observed at Sinabung throughout January 2018 leading up to an explosive eruption which occurred on the 19th February 2018. The eruption lasted 291 seconds with volcanic ash being ejected to FL550. Conditions for observing the movement of volcanic ash were good with little meteorological cloud obscuring the view from satellite imagery. Due to varying wind direction and strength spanning the height of the plume, multi-level VAAs were issued. Figure 8 below shows the distinct height and movement of the volcanic ash. On the 6th April, ground reports of an eruption to 5000m were received although a heavy deck of meteorological cloud made detection of any eruption difficult. Due to the height of the eruption, a dark brown areas amongst the deck of white meteorological cloud was observed. The event from eruption to Volcanic Ash being no longer discernible lasted around 19 hours. 3.4 Manam, Papua New Guinea – 25 August, 23 September and 5 October 2018 3.4.1 Hotspot activity observed over Manam with minor emission observed during the days leading up to the major eruption to FL500 at 24/2040z. The event occurred early in the morning just as visible Himawari-8 imagery was coming into the system. The imagery indicated that there were two discrete eruptions that occurred. There were multiple storms in the area which made the detection difficult paired with the fact that Manam typically does not exhibit ash signals in RGB imagery. Later the eruption was reported by ground observers, the volcano observatory and a strong SO2 signal was detected. Multiple advisories were issued during the event, but the initial eruption was quickly covered by meteorological cloud in the area and finalised 9 hours later. 3.4.2 On the 23rd September and 5th October there was suspicious cloud formation observed at Manam moving in different directions to other cloud in the area. Given the recent Manam eruptions and the lack of distinct ash signals observed on satellite imagery, the forecasters issued advisories to FL340 and FL320 respectively. These two events have yet to be confirmed by ground observers. 3.5 Soputan, Sulawesi, Indonesia – 3 October 2018 3.5.1 On the 2nd October, there was a ground report or Volcanic Observatory Notice for Aviation (VONA) indicating increased unrest and seismic activity at Mt Soputan. On the 3rd October at 0050 UTC, Soputan had an initial eruption to FL200, with further eruptions to varying heights. The advisory height reach FL250 for one of the eruptions but the area was covered in cloud making it difficult for an accurate assessment. The eruptions and activity lasted multiple days before being finalised. Minor activity remains at the volcano to date. The last time Soputan erupted was in 6th Feb 2016. 3.6 Salak, Java, Indonesia – 10 October 2018 3.6.1 On the 10th October at 10/1050 UTC, the forecasters noticed a rapidly growing cloud over the volcano with no other meteorological activity across Java.