By Simon Hradecky, created Saturday, May 21st 2011 23:01Z, last updated Thursday, May 26th 2011 10:26Z Icelandic Volcano Grimsvotn has erupted at 17:30Z on May 21st 2011, a minor eruption had already been expected similiar to the ones in the past (last in 2004). However, this time the volcano ash cloud has already been reported above FL300, the danger zone has been identified up to FL550 with the cloud estimated to have reached FL500. On May 22nd 06:00Z radar data estimated the ash plume to raise up to 15,000-17,000 meters (FL490-FL560). The eruption significantly reduced in intensity during May 24th and stopped early May 25th.



Iceland's Keflavik Airport suspended IFR operations at approximately 10:00L (10:00Z) on May 22nd (not NOTAMed so far), all flights for the day have been cancelled. The entire Iceland Airspace was subsequently closed for IFR traffic. On May 23rd 19:00Z most of the Icelandic Airspace opened again for IFR traffic including Keflavik Airport.



People in the Scottish Highlands reported finding their cars covered with volcanic ash Tuesday Morning (May 24th).



Scientists said on May 21st, that it was unlikely the eruption would cause similiar disruption to European Air Traffic like Eyjafjoll last year (see: Icelandic volcano disrupted aviation in Europe, Europe returning to normality). About one hour after the begin of the eruption the ash cloud however had already reached 11,000 meters (FL360), the Icelandic Meteorologic Institute reported.



The Icelandic Meteorologic Institute reported late May 24th that the plume of new ashes has reduced to about 2000 meters of height no longer posing a danger for aviation. The scientists are hopeful by comparing the eruption with previous events, that by weekend the eruption might cease. Only "old" ashes already in the air still hamper air traffic.



The Icelandic Meteorologic Institute reported in the morning of May 25th that there is clear evidence that the eruption of Grimsvotn has stopped. Starting around 03:00Z May 25th there has been no new output of volcanic material. In the afternoon of May 25th they reported that the eruption was much stronger and had produced substantially more ashes than Eyjafjoll's eruption last year.



According to NOAA's GFS weather data there are no significant high level winds above or around Iceland, high level wind directions are varying and wind speeds mainly computed below 20 knots, at the northern coast of Iceland up to 40 knots.



ICAO said: "ICAO Doc 96913 acknowledges that there is, as yet, no agreement as to the ash concentration level that would constitute a hazard to aircraft engines. As a result, ICAO recommends that aircraft avoid exposure to volcanic ash, regardless of the ash concentration; latterly, this has been termed the avoidance of 'visible ash'" and continued: "As a consequence of the lack of clarity as to what level of ash constitutes an unsafe level, the team also noted that there was no clear specification from the aviation community to the VAACs as to the level of ash contamination to be depicted on VAAC products. Rather than the current undefined approach of delineating areas with no ash, the team felt that there was a need to delineate an area in which existed a significant risk of a substantive adverse safety outcome." ICAO has followed with a recommendation for rule makers - national Civil Aviation Authorities - and operators - airlines - how to deal with the threat of ashes in principle enabling operators under supervision of civil aviation authorities to decide themselves to fly or not to fly after conducting and documenting mandatory risk assessments.



Europe's Central Flow Management Unit (CFMU) said on May 21st: "CFMU had been adviced by Icelandic met office that there has been a volcanic eruption of volcano Grimsvotn in Iceland at 20110521 1900Z. The plume hight has been confirmed by aircraft to 12 km or higher. Winds are currently N to NW."



On May 22nd the CFMU said, that the ash cloud would start to affect Scotland by Tuesday May 24th and possibly western France and northern Spain by Thursday if intensity of eruption continued at current levels.



On May 23rd the CFMU updated their statement to say that there is risk northern Europe might be affected within 48 hours as well.



The UK Civil Aviation Authority announced on May 23rd that air traffic in the UK may be disrupted starting May 24th due to volcanic ash, hinting on May 24th the entire Air Space might be closed by May 25th. On May 25th the situation in the UK recovered however and air traffic resumed.



The Finnish Transportation Safety Agency decided to enable operators to decide themselves whether to fly in ash contaminated area based on risk assessment recommended by ICAO.



Germany decided to permit IFR flights in areas of minor ash contamination (below 2000 microgram/cubic meter) while IFR flights in moderate and severe contamination are prohibited. In the evening of May 24th Germany decided that northern Germany's airports are to be closed. Bremen (from 01:00Z to 09:00Z), Hamburg (from 04:00Z to 10:00Z) and Berlin (from 09:00Z to 12:00Z) were closed on May 25th due to the ash cloud, so far some 700 flights have been cancelled.



KLM, BMI and British Airways cancelled their rotations to Edinburgh, Glasgow, Aberdeen and Newcastle on May 24th. Other airlines cancelled flights into the UK, too. No NOTAMs identifying danger zones related to the ash cloud have been released for Scottish ACC. On May 25th most flights into/out of Scotland are operating normally again.



Eurocontrol reported by May 24th 12:00Z that a total of 252 flights have been cancelled, mainly flights to and from Scotland. By the evening of May 25th more than 1000 flights had been cancelled.



Ryanair continued to fly to Scotland on May 24th. Ryanair's chairman claimed they had flown an aircraft into the "red zone" (severe ash contamination with more than 4000 micrograms/cubic meter) over Scotland and found no ash whatsoever. The UK Ministry of Transport contradicted stating the radar track of the aircraft shows the airplane did not get anywhere close to the red zone. By about 15:00Z on May 24th Ryanair cancelled all services to/from Scotland due to the ash cloud.



First flight disruptions occurred in Norway and Sweden on May 24th.



CFMU status message:



25/05/2011 Volcanic eruption in Iceland update @ 2011 UTC



Information to aircraft operators, attached is the current list of countries intentions when impacted by the Volcanic Ash Cloud.

Be advised that the Safety Assessment Column applies to the "Airline Operator"

This should be read as general guidelines only, and is only current at the time of publication.



report



Due to the increasing number of issued Notams, it is no longer possible for CFMU to keep the NOP portal updated with current Notam numbers.



Germany has issued a Notam A1890/11, where the intension of DFS is described, in case of ash contamination in German airspace. Information can also be found on their website www.dfs.eu



AIRCRAFT OPERATORS ARE STRONGLY

RECOMMENDED TO CLOSELY MONITOR ALL RELEVANT NOTAMS,

SIGMETS AND THE ASH CONCENTRATION CHARTS ON

WWW.METOFFICE.GOV.UK FOR FURTHER INFORMATION AND UPDATES.



Russian Federation airspace: the airspace will continue to be open and no restrictions are planned. The airlines are aware that they are accepting re-routed traffic by FPL. A corresponding remark i.e. re-routed due to volcano ash must be inserted in item 18 of FPL. FPLs must be copied to UUUWZDZX at all times.



Relevant NOTAMs:



A0263/11 - VOLCANIC ERUPTION IN VOLCANO GRIMSVOTN 1703-01 N6425.1 W01719.5.

EXPECTED TEMP DANGER AREA PLUS 18HRS.INCLUDING MEDIUM AND HIGH ASH

CONCENTRATION:

SFC/FL200

FL200/FL350

7333N06558W-7723N05545W-7529N01607W-6833N00000W-6240N00000W-

6328N00236W-7220N01736W-7500N04637W-6748N05043W-6624N06015W-

6809N06257W-7333N06558W

FL350/FL550

6938N06525W-7346N05856W-7714N03623W-7134N00655W-6733N00000W-

6100N00000W-6100N00918W-6938N02401W-7013N03712W-7454N03723W-

6817N06307W-6938N06525W

NO IFR CLEARANCE WILL BE ISSUED PENETRATING THE DANGER AREA.

ALL INTL AD OPEN. SFC - FL550, 26 MAY 19:00 2011 UNTIL 27 MAY 01:00 2011. CREATED:

26 MAY 07:25 2011



A0262/11 - VOLCANIC ERUPTION IN VOLCANO GRIMSVOTN 1703-01 N6425.1 W01719.5.

EXPECTED TEMP DANGER AREA PLUS 12HRS.INCLUDING MEDIUM AND HIGH ASH

CONCENTRATION:

SFC/FL200

6518N00617W-6435N00000W-6345N00000W-6416N00619W-6518N00617W

FL200/FL350

6741N06216W-6852N06409W-7139N06334W-7343N06555W-7650N05302W-

7615N03223W-7228N01208W-6634N00117W-6328N00405W-7013N01514W-

7424N03836W-7244N05012W-6720N05324W-6551N05907W-6741N06216W

FL350/FL550

6950N06535W-7326N05801W-7603N04119W-7353N01814W-6558N00116W-

6100N00425W-6100N01105W-6641N01959W-7004N03257W-7015N05035W-

6749N06228W-6950N06535W

NO IFR CLEARANCE WILL BE ISSUED PENETRATING THE DANGER AREA.

ALL INTL AD OPEN. SFC - FL550, 26 MAY 13:00 2011 UNTIL 26 MAY 19:00 2011. CREATED:

26 MAY 07:15 2011



A0249/11 - VOLCANIC ERUPTION IN VOLCANO GRIMSVOTN 1703-01 N6425.1 W01719.5.

DUE TO ONGOING VOLCANIC ACTIVITY A TEMPORARY DANGER AREA IS

ESTABLISHED WITHIN 15 NAUTICAL MILE RADIUS FROM THE VOLCANO. SFC - UNL, 25 MAY

11:15 2011 UNTIL 31 MAY 23:59 2011. CREATED: 25 MAY 11:18 2011



The ash cloud seen on May 21st (Photo: AFP):





The initial ash plume seen by Terra Satellite captured on May 22nd 05:15Z (Photo: Earthobservatory NASA/Terra):





Ash prediction charts May 26th 06:00Z (Graphics: VAAC):





Forecast Ash Concentration Chart for May 27th 00:00Z released May 26th 06:00Z (Graphics: VAAC):





Ash Concentration Chart May 26th 06:00Z (Graphics: VAAC):





Visual real color satellite image Terra May 25th 2011 11:57Z (Photo: MODIS/Terra):





Visual real color satellite image Aqua May 24th 2011 13:03Z (Photo: MODIS/Aqua):





Visual real color satellite image Terra May 23rd 2011 12:09Z (Photo: MODIS/Terra):





Visual real color satellite image Terra May 22nd 2011 13:04Z (Photo: MODIS/Terra):





Map with danger zones per NOTAMs of BIRD FIR May 24th 06:00Z (Graphics: AVH/Google Earth):







