(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
 (2) Issued:20180912/2315Z
 (3) Volcano:Sarychev Peak (CAVW #290240)
 (4) Current aviation colour code:YELLOW
 (5) Previous aviation colour code:green
 (6) Source:KVERT
 (7) Notice Number:2018-83
 (8) Volcano Location:N 48 deg 5 min E 153 deg 12 min
 (9) Area:Central Kuriles, Russia
(10) Summit Elevation:4906.88 ft (1496 m)
(11) Volcanic Activity Summary:Activity of the volcano Sarychev Peak increased. According to visual data from Matua Island, explosions sent ash up to 3-4 km a.s.l. at 19:03 UTC on 12 September. An ash cloud drifted to the south-east from the volcano. At 21:00 UTC an ash cloud 5.5x6 km in size moved for about 121 km to the south-east from the volcano. Later the ash cloud was not observed.

Activity of the volcano increased. Strong ash explosions could occur at any time.
(12) Volcanic cloud height:9840-13120 ft (3000-4000 m) AMSL Time and method of ash plume/cloud height determination: 20180912/1903Z – Visual data
(13) Other volcanic cloud information:Distance of ash plume/cloud of the volcano: 75 mi (121 km)
Direction of drift of ash plume/cloud of the volcano: SE / azimuth 127 deg
Time and method of ash plume/cloud determination: 20180912/2100Z – Himawari-8
(14) Remarks:A thermal anomaly over the volcano is noting sometimes from 07 May, 2018. Last moderate ash explosion of the volcano Sarychev Peak occurred on 11 August 2018.
(15) Contacts:Dr. Olga A. Girina, Head of KVERT, IVS FEB RAS
girina@kscnet.ru +74152202044

Duty 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/index_eng.php.

In 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.

CITATION GUIDELINES

For formal scientific citation of this VONA/KVERT Information Release, please use the following:
VONA/KVERT Information Release, September 12, 2018. KVERT, Institute of Volcanology and Seismology FEB RAS. URL: http://www.kscnet.ru/ivs/kvert/van/?n=2018-83.
Aviation Colour Codes

GREEN

Volcano is in normal, non-eruptive state

   or, after a change from a higher level:

Volcanic activity considered to have ceased, and volcano reverted to its normal, non-eruptive state.

YELLOW

Volcano is experiencing signs of elevated unrest above known background levels.    

 or, after a change from higher level:

Volcanic activity has decreased significantly but continues to be closely monitored for possible renewed increase.

ORANGE

Volcano is exhibiting heightened unrest with increased likelihood of eruption.

   or,

Volcanic eruption is underway with no or minor ash emission.
[specify ash-plume height if possible]

RED

Eruption is forecast to be imminent with significant emission of ash into the atmosphere likely.

  or,

Eruption is underway with significant emission of ash into the atmosphere.
[specify ash-plume height if possible]