HR: 0830h
AN: V11C-0517 [PDF]
TI: Photometric Observations of Aerosol Plumes From Volcanoes in Guatemala, El Salvador, and
Nicaragua
AU: * Lopez, T M
EM: tmlopez@mtu.edu
AF: Michigan Technological University, Department of Geological and Mining Engineering and Sciences,
1400 Townsend Drive, Houghton, MI 49931 United States
AU: Watson, I
EM: watson@mtu.edu
AF: Michigan Technological University, Department of Geological and Mining Engineering and Sciences,
1400 Townsend Drive, Houghton, MI 49931 United States
AU: Rodriguez, L A
EM: larodrig@mtu.edu
AF: Michigan Technological University, Department of Geological and Mining Engineering and Sciences,
1400 Townsend Drive, Houghton, MI 49931 United States
AU: Branan, Y K
EM: ykbranan@mtu.edu
AF: Michigan Technological University, Department of Geological and Mining Engineering and Sciences,
1400 Townsend Drive, Houghton, MI 49931 United States
AU: Rose, W I
EM: raman@mtu.edu
AF: Michigan Technological University, Department of Geological and Mining Engineering and Sciences,
1400 Townsend Drive, Houghton, MI 49931 United States
AU: Bluth, G J
EM: gbluth@mtu.edu
AF: Michigan Technological University, Department of Geological and Mining Engineering and Sciences,
1400 Townsend Drive, Houghton, MI 49931 United States
AB:
Visible to near infrared sun-photometers were used to measure spectral optical depths in order to infer particle size
distributions of volcanic aerosols in plumes from volcanoes in the Central American arc. Data were taken from the following
volcanoes on the listed dates in 2002: Pacaya, Guatemala on January 14, 16, 20 and 21; Santa Ana, El Salvador on January 24
and 26; San Miguel, El Salvador on January 28; and San Cristobal, Nicaragua on February 3. These volcanoes were chosen for
study because of: good calibration of the sun-photometer (Pacaya), the presence (and effects) of a crater lake (Santa Ana)
and a paucity of previous measurements (San Miguel and San Cristobal).
The optical properties of these tropospheric volcanic aerosols will be retrieved after the removal of the background optical
depth. Through the application of the Angstrom equation and a King-type inversion, the Angstrom coefficients, the particle
size distribution, and the effective radius (Reff) will be determined (Watson and Oppenheimer, 2000; 2001). Through these
methods we hope to increase the understanding of emission and conversion processes of tropospheric volcanic aerosols. We
hope the interpretation of these data will help elucidate environmental and climatic effects of these aerosols on local to
global scales, and provide insight into modulation of aerosol emissions through the presence of a crater lake.
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0370 Volcanic effects (8409)
DE: 0994 Instruments and techniques
DE: 8409 Atmospheric effects (0370)
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2003 Fall Meeting