Forecasting of volcanic ash for the Norwegian airspace Picture courtesy: Magnús Tumi Guðmundsson H. Fagerli, H. Klein, A. Nyiri, B. Steensen, M. Schulz, A. Mortier, A. Lauen Borg, A. Valdebenito, N. Kristiansen, A. Kylling, E. Sollum, S. Eckhardt, A. Stohl, K. Tørseth
Overview Scientific Work Inversions Norwegian Agency Group for Volcanic Ash Advisory (EVA) Operative System of EVA Setup Exercises Future Development
Eruption of Jebel at Tair - 2008
Eyjafjalljokull eruption 2010 FLEXPART Forecasts use NCEP GFS data, Analyses ECMWF data Simulation of volcanic ash (31 size bins) gravitational settling dry, wet deposition wet deposition Time resolved source term
Grímsvötn Eruption 2012 VAAC issued a warning that many airports in Norway should be closed EVA (Agency Group for Volcanic Ash) a group of 2 research institutes, AVINOR and the Civil Aviation Authority Norway had a crisis meeting. FLEXPART simulation and satellite images showed, that those airports will not be affected. First time in Europe aircrafts flew, even though VAAC did not recommend it Moxnes and Kristiansen 2010
Norwegian National Ash project - EVA Partner: Meteorological Office of Norway (MET Norway) NILU - Norwegian institute for air research (NILU) Tasks: run an operational forecasting system for atmospheric dispersion of volcanic ash Results: Information on the impact of ash to the Norwegian air space, and is a supplement to the assessments made by the VAACs. Funding: AVINOR airport operator Users: Airlines Helicopters and smaller aircraft (Military, Ambulance and Police)
The different components in the EVA project Observations: (operational, NRT) Ceilometers (Bergen, Oslo) Satelitte observations (SEVIRI, IASI, other) Surface observations (luftkvalitet.info) Dispersion models: eemep and FLEXPART, input meteorology ECMWF, GFS Emission: Mastin, USGS, inversion of emissions Products: Maps of concentrations with low, medium, high concentrations (similar to VAAC) Column mass burden charts editerted VAAC polygoner (SIGMET) / max values on flight levels Focus on Norway and the northernmost areas (up to 78 N)...but: VAAC is standard, our recommandations will only deviate from VAAC if there is sufficient information from observations (and model)
eemep vs FLEXPART simulations Example for maps produced: 6h max on FL000-FL200 eemep operational 6-hours max value Updated 4 times a day 48 hours prediction ECMWF meteorological data Flexpart Semi operational 6-hours max Runs minimum 1x per day 48 hours prediction GFS meteorological data
Procedure during an ash crisis event Notification from Iceland (IMO) to MET-> Model runs/observation collection MET notifies NILU -> Model runs/observation Civil aviation authorities call for a meeting (CAA, Avinor, NILU, MET) EVA meeting to assess to situation MET sends a SIGMET (of ash concentrations exceeding 0.2mg/m3) MET/NILU publishes recommendations for airlines Model does not compile, input files no longer compatible Satellite retrival process died, wrong settings in login shell Libraries not found, data directory pathname forgotten
Monthly exercises / VOLCICE
Comparison eemep/flexpart for exercise eruption During 48 hours of transport the horizontal distribution is very similar, however the height of the ash in FLEXPART is above eemep Simulation based on a calculated distribution based on an emission height
Use of satellite observations in the national system We need a coverage also to Svalbard, out of SEVIRI (geostationary) range, therefore IIASI (orbit) is used Operational for quantitative estimation: SEVIRI data (software developed at NILU and set in production at MET) Every 15min we get SEVIRI data and analyse for ash if ash is detected amount TC value is retrieved Retrivals are based on: Kylling, A., Kristiansen, N., Stohl, A., Buras-Schnell, R., Emde, C. and Gasteiger, J., 'A model sensitivity study of the impact of clouds on satellite detection and retrieval of volcanic ash', Atmospheric Measurement Techniques, 8, 1935-1949, doi:10.5194/amt-8-1935-2015, 2015. IIASA: ash detection only Kylling, A., 'Ash and ice clouds during the Mt Kelud February 2014 eruption as interpreted from IASI and AVHRR/3 observations', Atmospheric Measurement Techniques, 9, 15, 2103-2117, doi:10.5194/amt-9-2103-2016, 2016.
Calculation of the source term emission inversion The inversion algorithm finds a new emission estimate (and height) by weighting model data against satelitte observations Coupled both to eemep and FLEXPART Pre-operational
Conclusions We established an operational system which will give add on information to the data issued by the VAAC Focuses on the Norwegian Air space, funded by AVINOR / operational for commercial flights, ambulance, police and military Operational setup and take part in monthly exercise (Long way from scientific idea to an operational tool) Combination of 2 models with 2 different meteorological datasets Observation: Use of a geostationary satellite (SEVIRI), orbiting (IIASI), ground measurements and ceilometers Provide reports the airlines make their own decision, are involved in creation of reports In case of volcanic ash will be handeld same as weather phenomenons Next steps: Uncertainty calculation by use of met data ensemble Operational Inversion Use of ceilometers, enlarging network
Thank you for your attention! Radar observations of Eyjafjallajökull eruption site 15 April 2010