A-Train observations of the 2010 eruption of Eyjafjallajökull volcano (Iceland) S.A. Carn 1, N.A. Krotkov 2, K. Yang 2, A.J. Prata 3 1. Michigan Technological University, Houghton, MI, USA 2. GEST Center, UMBC, Baltimore, MD, USA 3. Norwegian Institute for Air Research, Kjeller, Norway
Global air routes and potentially active volcanoes High density of air routes Unusual wind direction Small volcanic ash particles No constraints on safe concentration of ash for aircraft
Aviation hazards from volcanic clouds Acute hazards Engine failure due to melted ash Abrasion of windshield Effects on avionics Secondary hazards Corrosion by ash, sulfuric acid Rerouting is expensive Accurate and timely mapping is required From: Volcanoes; Crucibles of Change, Princeton U. Press, Princeton, 1997.
Two near-disastrous volcanic cloud encounters Galunggung ash cloud Ladies and gentlemen, this is your captain speaking. We have a small problem. All four engines have stopped. We are doing our damnedest to get them under control. I trust you are not in too much distress. Capt. Eric Moody, BA Flight 9 ~2 g/m 3 ash? BA 009 (B747), Kuala Lumpur Perth, 24 June 1982 KLM 867 (B747), Amsterdam Tokyo, 15 December 1989 (Redoubt, AK)
Volcanic Ash Advisory Centers (VAACs)
Eruption sequence Fimmvörðuháls eruption 1994, 1999, 2009 and early 2010 Unrest and magma injections 20 March to 12 April Small flank eruption at Fimmvörðuháls 14 April to 25 May Explosive eruption in summit crater Eyjafjallajökull eruption Eyjafjallajökull
Pressure analysis 14 April 2010
Pressure analysis 15 April 2010
OMI SO 2 and AI time series Glacial meltwater sequestering SO 2?
Volcanic Ash Advisory (VAA) and OMI AI April 16 NAME dispersion model (UK Met Office)
Comparison of VAA and OMI AI May 6 Before 21 April zero tolerance 21 April 4 May >2 mg m -3 no go After 4 May >4 mg m -3 no go
Model initialization for volcanic eruptions Mass flux at vent Spatial extent Plume injection height Particle size distribution Composition (e.g. ash vs. sulfate) Meteorology Some processes (e.g., ash aggregation) not yet treated MISR visible image (courtesy of NASA Earth Observatory Web Site)
Altitude [km] A-Train measurements April 16 CloudSat Ash Aqua MODIS Aura OMI AI CALIPSO
A-Train measurements May 8 CloudSat L1A
Derivation of ash concentrations CALIPSO + SEVIRI
In-situ measurements by DLR-Falcon Falcon 20E D-CMET, DLR Oberpfaffenhofen PI: Ulrich Schumann
In-situ measurements by DLR-Falcon May 2 Plume age 7 hours, ~450 km from volcano 3 minutes in volcanic plume at 3.4-3.7 km altitude Courtesy of the Falcon team, DLR O 3 decrease, CO increase, SO 2 > 150 ppbv (0.1 ppbv background)
In-situ measurements by DLR-Falcon May 17 ppb Ash mass concentration and SO 2 well-correlated Validates use of SO 2 as a proxy for volcanic ash in volcanic clouds Courtesy of the Falcon team, DLR
Ground-based DOAS measurements of volcanic plume April 23-24, 2010 G. Sawyer, E. Ilyinskaya, R. Martin, Cambridge Univ., UK
Ground-based DOAS measurements April 23
Summary and road forward A-Train observations of Eyjafjallajökull volcanic plume Advantage of UV OMI data: high sensitivity to SO 2 /ash Ability to detect ash in the presence of clouds Limitations: data latency, temporal resolution, daytime only Need VFD, Direct Broadcast? CALIPSO/CloudSat profiles useful but not available operationally Mostly lower tropospheric plumes: no MLS SO 2 signal found In-situ measurements offer OMI validation opportunities SO 2 and ash sampling in volcanic plumes Future: quantitative ash retrievals and mapping Need vertical profile/altitude of volcanic cloud Models need to ingest satellite observations in (near) real time Improve ash treatment in models (e.g., aggregation) Volcanic ash refractive indices (UV to IR), size and shape distributions required High spatial resolution needed TROPOMI
E. Bruhl, 1822 1821-23 Eyjafjallajökull eruption