(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA) (2) Issued:20210808/1035Z (3) Volcano:Chirinkotan (CAVW #290260) (4) Current aviation colour code:ORANGE (5) Previous aviation colour code:green (6) Source:KVERT (7) Notice Number:2021-81 (8) Volcano Location:N 48 deg 58 min E 153 deg 28 min (9) Area:Northern Kuriles, Russia (10) Summit Elevation:724 m (2374.72 ft)(11) Volcanic Activity Summary:The moderate explosive event of the volcano Chirinkotan (Chirinkotan Island) occurred at 06:45 UTC on 08 August. Ash cloud is drifting for about 86 km to the west-southwest of the volcano. \n\nThe moderate explosive event of the volcano occurred at 06:45 UTC on 08 August. Ash explosions up to 10-15 km (32,800-49,200 ft) a.s.l. could occur at any time. Ongoing activity could affect international and low-flying aircraft. (12) Volcanic cloud height:2000-2500 m (6560-8200 ft) AMSL Time and method of ash plume/cloud height determination: 20210808/0940Z – Himawari-8(13) Other volcanic cloud information:Distance of ash plume/cloud of the volcano: 86 km (53 mi)\nDirection of drift of ash plume/cloud of the volcano: WSW / azimuth 250 deg \nTime and method of ash plume/cloud determination: 20210808/0940Z – Himawari-8\nStart time of explosion and how determined: 20210808/0645Z – Satellite data(14) Remarks:(15) Contacts:Dr. Olga A. Girina, Head of KVERT, IVS FEB RAS\ngirina@kscnet.ru +74152202044\n\nDuty scientist: +79622825253 (16) Next Notice:A new VONA will be issued if conditions change significantly or the colour code is changed. VONAs are posted at http://www.kscnet.ru/ivs/kvert/.\n\nIn Russia, KVERT, on behalf of the Institute of Volcanology and Seismology (IVS) FEB RAS, is responsible for providing information on volcanic activity to international air navigation services for the airspace users.