Artículos de revistas
Monitoring volcanic thermal anomalies from space: Size matters
Registro en:
Journal Of Volcanology And Geothermal Research. Elsevier Science Bv, v. 203, n. 41671, n. 48, n. 61, 2011.
0377-0273
WOS:000292066900005
10.1016/j.jvolgeores.2011.04.008
Autor
Murphy, SW
de Souza, CR
Oppenheimer, C
Institución
Resumen
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Measuring temperatures on volcanoes from space provides important constraints on the transfer of mass and heat to the Earth's surface. Time series of multispectral infrared images, acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) between 2000 and 2009, were inspected to investigate fluctuations in thermal anomalies at both Mount Erebus (Antarctica) and Lascar volcano (Chile). Several thermal metrics were explored: i) maximum pixel temperatures above background, ii) the spatial extent of low, moderate and high temperature anomalies, and iii) the spatial extent of short-wave infrared anomalies. The maximum pixel temperature metric correlated to eruptive events at Lascar volcano yet displayed significant scatter at Erebus. The spatial extent of both temperature and short-wave infrared anomalies correlates well with eruptive activity at both volcanoes. Limited variation in the size of thermal anomalies was observed at Erebus throughout the time series due to the stability of a long-lived lava lake, with the exception of a seasonal expansion in low temperature anomalies associated with localized snow-melt at the peak. This finding has implications for the interpretation of low temperature anomalies at other volcanoes. At least two different types of precursory signals are identified at Lascar: i) a gradual increase and ii) a dip, in the size and intensity of thermal anomalies. These thermal precursors appear to be associated with different eruptive styles. The former precedes a relatively shallow, short lived eruption; the later a prolonged eruptive period. Such thermal precursors could therefore help to constrain not only the timing but also the style and duration of an imminent eruptive episode. (C) 2011 Elsevier B.V. All rights reserved. 203 41671 48 61 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)