Abstract:
:On April 14, 2010, when meltwaters from the Eyjafjallajökull glacier mixed with hot magma, an explosive eruption sent unusually fine-grained ash into the jet stream. It quickly dispersed over Europe. Previous airplane encounters with ash resulted in sandblasted windows and particles melted inside jet engines, causing them to fail. Therefore, air traffic was grounded for several days. Concerns also arose about health risks from fallout, because ash can transport acids as well as toxic compounds, such as fluoride, aluminum, and arsenic. Studies on ash are usually made on material collected far from the source, where it could have mixed with other atmospheric particles, or after exposure to water as rain or fog, which would alter surface composition. For this study, a unique set of dry ash samples was collected immediately after the explosive event and compared with fresh ash from a later, more typical eruption. Using nanotechniques, custom-designed for studying natural materials, we explored the physical and chemical nature of the ash to determine if fears about health and safety were justified and we developed a protocol that will serve for assessing risks during a future event. On single particles, we identified the composition of nanometer scale salt coatings and measured the mass of adsorbed salts with picogram resolution. The particles of explosive ash that reached Europe in the jet stream were especially sharp and abrasive over their entire size range, from submillimeter to tens of nanometers. Edges remained sharp even after a couple of weeks of abrasion in stirred water suspensions.
journal_name
Proc Natl Acad Sci U S Aauthors
Gislason SR,Hassenkam T,Nedel S,Bovet N,Eiriksdottir ES,Alfredsson HA,Hem CP,Balogh ZI,Dideriksen K,Oskarsson N,Sigfusson B,Larsen G,Stipp SLdoi
10.1073/pnas.1015053108subject
Has Abstractpub_date
2011-05-03 00:00:00pages
7307-12issue
18eissn
0027-8424issn
1091-6490pii
1015053108journal_volume
108pub_type
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