ACPD Atmospheric Chemistry and Physics Discussions ACPD 1680-7375 Copernicus GmbH Göttingen, Germany 10.5194/acpd-11-7757-2011 Sulphur dioxide as a volcanic ash proxy during the April–May 2010 eruption of Eyjafjallajökull Volcano, Iceland Thomas H. E. 1 Prata A. J. 2 Department of Geological Engineering and Sciences, Michigan Technological University, Houghton, MI, USA Nordic Institute for Air Research (NILU), Kjeller, Norway 07 03 2011 11 3 7757 7780 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys-discuss.net/11/7757/2011/acpd-11-7757-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/11/7757/2011/acpd-11-7757-2011.pdf

The volcanic ash cloud from the eruption of Eyjafjallajökull volcano in April and May 2010 resulted in unprecedented disruption to air traffic in Western Europe causing significant monetary loses and highlighting the importance of efficient volcanic cloud monitoring. The feasibility of using SO<sub>2</sub> as a tracer for the ash released during the eruption is investigated here through comparison of ash retrievals from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) with SO<sub>2</sub> measurements from a number of infrared and ultraviolet satellite-based sensors. Results demonstrate that the eruption can be divided into an initial ash-rich phase, a lower intensity middle phase and a final phase where considerably greater quantities of both ash and SO<sub>2</sub> were released. Comparisons of ash-SO<sub>2</sub> dispersion indicate that despite frequent collocation of the two species, there are a number of instances throughout the eruption where separation is observed. This separation occurs vertically due to the more rapid settling rate of ash compared to SO<sub>2</sub>, horizontally through wind shear and temporally through volcanological controls on eruption style. The potential for the two species to be dispersed independently has consequences in terms of aircraft hazard mitigation and highlights the importance of monitoring both species concurrently.

 References Bernard, A. and Rose, W.: The injection of sulfuric acid aerosols in the stratosphere by the El Chichón volcano and its related hazards to the international air traffic, Nat. Hazards, 3, 59–67, http://dx.doi.org/10.1007/bf00144974doi:10.1007/bf00144974, 1990. Berrisford, P. D., Dee, K., Fielding, M., Fuentes, P., Kallberg, S., Kobayashi, S., and Uppala, S.: The ERA-Interim archive, Report Series. 1, European Centre for Medium-Range Weather Forecasts, Shinfield Park, Reading, 2009. BGS: Changing eruption styles at Eyjafjallajökull in Iceland: http://www.bgs.ac.uk/research/highlights/changingEruptionStyles.html, last access: 17 February 2011, 2010. CAA: Rationale for the removal of the current volcanic ash buffer zone, v.1.1, Civil Aviation Authority, 2010. Carn, S., Krueger, A., Krotkov, N., Yang, K., and Evans, K.: Tracking volcanic sulfur dioxide clouds for aviation hazard mitigation, Nat. Hazards, 51, 325–343, http://dx.doi.org/10.1007/s11069-008-9228-4doi:10.1007/s11069-008-9228-4, 2009. Casadevall, T. J., Delos Reyes, P. J., and Schneider, D. J.: The 1991 Pinatubo eruptions and their effects on aircraft operations, in: Fire and mud: eruptions and lahars of Mount Pinatubo, Philippines, edited by: Newhall, C. G. and Punongbayan, R. S., University of Washington Press, Seattle/London, 1071–1088, 1996. Clarisse, L., Coheur, P. F., Prata, A. J., Hurtmans, D., Razavi, A., Phulpin, T., Hadji-Lazaro, J., and Clerbaux, C.: Tracking and quantifying volcanic SO<sub>2</sub> with IASI, the September 2007 eruption at Jebel at Tair, Atmos. Chem. Phys., 8, 7723–7734, http://dx.doi.org/10.5194/acp-8-7723-2008doi:10.5194/acp-8-7723-2008, 2008. Eckhardt, S., Prata, A. J., Seibert, P., Stebel, K., and Stohl, A.: Estimation of the vertical profile of sulfur dioxide injection into the atmosphere by a volcanic eruption using satellite column measurements and inverse transport modeling, Atmos. Chem. Phys., 8, 3881–3897, http://dx.doi.org/10.5194/acp-8-3881-2008doi:10.5194/acp-8-3881-2008, 2008. Eisinger, M. and Burrows, J. P.: Tropospheric sulfur dioxide observed by the ERS-2 GOME instrument, Geophys. Res. Lett., 25, 4177–4180, http://dx.doi.org/10.1029/1998gl900128doi:10.1029/1998gl900128, 1998. ESCAP: Review of developments in transport in Asia and the Paci?c 2005, Economic and Social Commission for Asia and the Pacific, 2005. Guffanti, M., Casadevall, T. J., and Budding, K.: Encounters of Aircraft with Volcanic Ash Clouds: A Compilation of Known Incidents, 1953–2009, USGS, 2010. Hjaltadóttir, S., Sigmundsson, F., Oddsson, B., Hreinsdóttir, S., Roberts, M. J., and Sveinbjörnsson, H.: Eruption in Eyjafjallajökull Status Report: 15:00 GMT, 4 May 2010, Icelandic Meteorological Office and Institute of Earth Sciences, University of Iceland, 2010. IATA: Press Release: Volcano Crisis Cost Airlines $1.7 Billion in Revenue – IATA Urges Measures to Mitigate Impact: http://www.iata.org/pressroom/pr/Pages/2010-04-21-01.aspx, last access: 2 February 2011, 2010. ICAO: EUR DOC 019 – Volcnic Ash Contingency Plan – EUR and NAT regions, 2nd edn., International Civil Aviation Authority, 2010. Icelandic Met Office: Update on activity in Eyjafjallajökull: http://en.vedur.is/earthquakes-and-volcanism/articles/nr/1884, last access: 3 February 2011, 2010. Jones, A., Thomson, D., Hort, M., and Devenish, B.: The U.K. Met Office's Next-Generation Atmospheric Dispersion Model, NAME III, in: Air Pollution Modeling and Its Application XVII, edited by: Borrego, C. and Norman, A.-L., Springer US, 580–589, 2007. Kerr, J. B., McElroy, C.T. and Olafson, R.A.,: Measurements of Ozone with the Brewer Ozone Spectrophotometer, Proc. Int. Ozone Symposium, 74–79, 1980. Krueger, A. J.: Sighting of El Chichon Sulfur Dioxide Clouds with the Nimbus 7 Total Ozone Mapping Spectrometer, Science, 220, 1377–1379, http://dx.doi.org/10.1126/science.220.4604.1377doi:10.1126/science.220.4604.1377, 1983. Krueger, A. J., Walter, L. S., Bhartia, P. K., Schnetzler, C. C., Krotkov, N. A., Sprod, I., and Bluth, G. J. S.: Volcanic sulfur dioxide measurements from the total ozone mapping spectrometer instruments, J. Geophys. Res., 100, 14057–14076, http://dx.doi.org/10.1029/95jd01222doi:10.1029/95jd01222, 1995. Pavolonis, M. J., Feltz, W. F., Heidinger, A. K., and Gallina, G. M.: A Daytime Complement to the Reverse Absorption Technique for Improved Automated Detection of Volcanic Ash, J. Atmos. Ocean Tech., 23, 1422–1444, http://dx.doi.org/10.1175/JTECH1926.1doi:10.1175/JTECH1926.1, 2006. Prata, A. J.: Observations of volcanic ash clouds in the 10–12 $μ$m window using AVHRR/2 data, Int. J. Remote. Sens., 10, 751–761, 1989a. Prata, A. J.: Infrared radiative transfer calculations for volcanic ash clouds, Geophys. Res. Lett., 16, 1293–1296, http://dx.doi.org/10.1029/GL016i011p01293doi:10.1029/GL016i011p01293, 1989b. Prata, A. J. and Bernardo, C.: Retrieval of volcanic SO<sub>2</sub> column abundance from Atmospheric Infrared Sounder data, J. Geophys. Res., 112, D20204, http://dx.doi.org/10.1029/2006jd007955doi:10.1029/2006jd007955, 2007. Prata, A. J. and Grant, I. F.: Retrieval of microphysical and morphological properties of volcanic ash plumes from satellite data: Application to Mt Ruapehu, New Zealand, Q. J. Roy. Meteor. Soc., 127, 2153–2179, http://dx.doi.org/10.1002/qj.49712757615doi:10.1002/qj.49712757615, 2001. Prata, A. J. and Kerkmann, J.: Simultaneous retrieval of volcanic ash and SO<sub>2</sub> using MSG-SEVIRI measurements, Geophys. Res. Lett., 34, L05813, http://dx.doi.org/10.1029/2006gl028691doi:10.1029/2006gl028691, 2007. Rodgers, C. D.: Inverse Methods for Atmospheric Sounding, Series on Atmospheric Oceanic and Planetary Physics, World Scientific Publishing, Singapore, 2000. Rose, W. I., Delene, D. J., Schneider, D. J., Bluth, G. J. S., Krueger, A. J., Sprod, I., McKee, C., Davies, H. L., and Ernst, G. G. J.: Ice in the 1994 Rabaul eruption cloud: implications for volcano hazard and atmospheric effects, Nature, 375, 477–479, 1995. Smithsonian Institution: Large explosions from the summit crater; ash plumes close airspace in Europe, BGVN, 33:04, 2010. Stamnes, K. and Swanson, R. A.: A New Look at the Discrete Ordinate Method for Radiative Transfer Calculations in Anisotropically Scattering Atmospheres, Journal of the Atmospheric Sciences, 38, 387–399, http://dx.doi.org/10.1175/1520-0469(1981)038<0387:ANLATD>2.0.CO;2doi:10.1175/1520-0469(1981)038<0387:ANLATD>2.0.CO;2, 1981. %Stohl, A., Prata, A. J., Eckhardt, S., Clarisse, L., Durant, A., Henne, S., %Kristiansen, N. I., Minikin, A., Schumann, U., Seibert, P., Stebel, K., %Thomas, H. E., Thorsteinsson, T., Tørseth, m. K., and Weinzierl, B.: %Determination of time- and height-resolved volcanic ash emissions for %quantitative ash dispersion modeling: The 2010 Eyjafjallajokull eruption, %Atmos. Chem. Phys., in review. Stohl, A., Prata, A. J., Eckhardt, S., Clarisse, L., Durant, A., Henne, S., Kristiansen, N. I., Minikin, A., Schumann, U., Seibert, P., Stebel, K., Thomas, H. E., Thorsteinsson, T., Tørseth, K., and Weinzierl, B.: Determination of time- and height-resolved volcanic ash emissions for quantitative ash dispersion modeling: the 2010 Eyjafjallajökull eruption, Atmos. Chem. Phys. Discuss., 11, 5541–5588, http://dx.doi.org/10.5194/acpd-11-5541-2011doi:10.5194/acpd-11-5541-2011, 2011. Swadzba, L., Maciejny, A., Formanek, B., Liberski, P., Podolski, P., Mendala, B., Gabriel, H., and Poznanska, A.: Influence of coatings obtained by PVD on the properties of aircraft compressor blades, Surf. Coat. Tech., 78, 137–143, 1996. Thomas, H. E., Watson, I. M., Carn, S. A., Prata, A. J., and Realmuto, V. J.: A comparison of AIRS, MODIS and OMI sulphur dioxide retrievals in volcanic clouds, Geomatics, Nat. Hazards Risk, in press, 2011. Torres, O., Tanskanen, A., Veihelmann, B., Ahn, C., Braak, R., Bhartia, P. K., Veefkind, P., and Levelt, P.: Aerosols and surface UV products from Ozone Monitoring Instrument observations: An overview, J. Geophys. Res., 112, D24S47, http://dx.doi.org/10.1029/2007jd008809doi:10.1029/2007jd008809, 2007. \clearpage Wen, S. and Rose, W. I.: Retrieval of sizes and total masses of particles in volcanic clouds using AVHRR bands 4 and 5, J. Geophys. Res., 99, 5421–5431, http://dx.doi.org/10.1029/93jd03340doi:10.1029/93jd03340, 1994. Yang, K., Krotkov, N. A., Krueger, A. J., Carn, S. A., Bhartia, P. K., and Levelt, P. F.: Retrieval of large volcanic SO<sub>2</sub> columns from the Aura Ozone Monitoring Instrument: Comparison and limitations, J. Geophys. Res., 112, D24S43, http://dx.doi.org/10.1029/2007jd008825doi:10.1029/2007jd008825, 2007.