ORIGINAL PAPER Dispersion modeling of volcanic ash clouds: North Pacific eruptions, the past 40 years: 1970–2010 P. W. Webley • K. Dean • R. Peterson • A. Steffke • M. Harrild • J. Groves Received: 6 September 2011 / Accepted: 15 November 2011 / Published online: 30 November 2011 Ó Springer Science+Business Media B.V. 2011 Abstract Over the last 40 years, there have been numerous volcanic eruptions across the North Pacific (NOPAC) region that posed a potential threat to both local communities and transcontinental aircraft. The ability to detect these volcanic clouds using satellite remote sensing and predict their movement by dispersion modeling is a major component of hazard mitigation. The Puff volcanic ash transport and dispersion model, used by the Alaska Volcano Observatory, was used to illustrate the impact that these volcanic ash clouds have made across the NOPAC and entire Polar region over the past 40 years. Nearly, 400 separate ash clouds were analyzed that were either reported or detected to have reached above 6 km (20,000 ft) above sea level, an average of one ash cloud every 1.25 months. Particular events showed that ash clouds can be tracked from Alaska to Greenland (Crater Peak, Mount Spurr in 1992), from Kamchatka to Alaska (Kluvicheskoi Volcano in 1994), from Alaska to California (Mount Cleveland Volcano in 2001) and from multiple events within 1 day (Mount Augustine Volcano in 2006). This study showed the vast number of events that have impacted this Polar region and how tracking them is useful for hazard mitigation. Keywords Polar regions Á Volcanic ash Á Dispersion modeling P. W. Webley (&) Á K. Dean Á J. Groves Alaska Volcano Observatory, Geophysical Institute, University of Alaska Fairbanks, 903 Koyukuk Drive, Fairbanks, AK 99775, USA e-mail: pwebley@gi.alaska.edu R. Peterson Department of Mechanical Engineering, University of Alaska Fairbanks, Duckering Building, Fairbanks, AK 99775, USA A. Steffke Hawai’i Institute of Geophysics and Planetology, University of Hawai’i at Manoa, 1680 East–West Road, POST 602, Honolulu, HI 96822, USA M. Harrild Department of Geography, Environment and Disaster Management, Faculty of Business, Environment and Society, University of Coventry, George Eliot Building, Priory Street, Coventry CV1 5FB, UK 123 Nat Hazards (2012) 61:661–671 DOI 10.1007/s11069-011-0053-9