An evaluation of volcanic cloud detection techniques during recent significant eruptions in the western ‘Ring of Fire’

Abstract

We examined recent volcanic cloud events in the Western Pacific and Indonesian area, to validate the performance of remote sensing techniques used to support the International Airways Volcano Watch (IAVW). Five events were considered, during which eruptions from eight volcanoes injected ash into the upper troposphere or lower stratosphere. For one of the eruptions, at Miyakejima, Japan, at least five aircraft encountered volcanic ash clouds, and the cost to three operators alone exceeded US $12,000,000 in aircraft repairs, diversions, and lost operating time. We performed 'reverse' absorption and 'pattern analysis' using GMS-5/VISSR, MODIS and AVHRR data, and we examined TOMS SO 2 and Aerosol Index data, surface-based observations, pilot reports, and dispersion model output. Our results verify that the introduction of 'reverse' absorption using the geostationary GMS-5 platform significantly enhanced our capacity to monitor volcanic ash clouds in the region. In one case, we tracked an eruption cloud for approximately 80 hours. The primary impediment to remote monitoring is the presence of overlying cloud, or substantial amounts of ice within the volcanic clouds. TOMS data showed success in identifying volcanic clouds during these conditions, but was limited by the infrequency of observations. More effective future operation of the IAVW relies on developing complementary methods of volcanic cloud remote sensing, and greatly increasing the amount and quality of available surface and air observations, including observations of precursor activity. An understanding of the likely future limitations of remote sensing techniques will aid in the refining of IAVW procedures.

Observing and understanding the Southeast Asian aerosol system by remote sensing: An initial review and analysis for the Seven Southeast Asian Studies (7SEAS) program

“…Often treated as a quick qualitative indicator of large events, it has been utilized for situational awareness, broad climatologies, interannual variability, and rough comparisons to models for smoke (e.g., Herman et al, 1997;Ji and Stocker, 2002;Duncan et al, 2003b) and volcanic emissions Tupper et al, 2004;Carn et al, 2008). This is particularly true for the massive Indonesia El Niño smoke events of 1997 and 2006 (e.g., Duncan et al, 2003a;Gonzi and Palmer, 2010) and large pyro-CBs (Rosenfeld et al, 2007;Fromm et al, 2008Fromm et al, , 2010.…”

A multidisciplinary effort to assign realistic source parameters to models of volcanic ash-cloud transport and dispersion during eruptions

“…Letters in parentheses indicate subordinate magma types. Observations that form the basis for these values are described in Mastin et al (in preparation A C C E P T E D M A N U S C R I P T Miller and Chouet (1994); 15 Scott and McGimsey (1994); 16 Naranjo et al (1986); 17 Neal et al (1995);18 Eichelberger et al (1995);19 (McGimsey et al, 2001) 20 Thorarinsson and Sigvaldason (1971);21 Gronvold et al (1983);22 Smithsonian Institution (2002); 23 Thorarinsson (1949); 24 Anderson and Flett (1903);25 Carey and Sigurdsson (1978);26 Carey and Sigurdsson (1986);27 Scasso et al (1994); 28 Naranjo S. et al (1993);29 Rose (1972);30 Carey and Sparks (1986) Hill et al (1998);34 Bonis and Salazar (1973);35 Rose et al (1973); 36 Tupper et al (2004); 37 Nakada et al (2005) Taken from Table 2 in Rose et al (2007). The range represents the variation using three methods: a modified method of Murrow et al (1980) (Walker, 1981a, (Walker, 1981a, (Walker, 1981a, Table 1 …”

Initial fate of fine ash and sulfur from large volcanic eruptions

“…Prata and Kerkmann, 2007;Guo et al, 2004). This is extremely helpful for aviation safety, as fine ash is a source of danger, which in low concentration can not be seen by the pilots of an air plane (Tupper et al, 2004). The transport of ash has been simulated in dispersion models (e.g.…”