Comparison of COSPEC and two miniature ultraviolet spectrometer systems for SO2 measurements using scattered sunlight

Bulletin of Volcanology
By: , and 

Links

Abstract

The correlation spectrometer (COSPEC), the principal tool for remote measurements of volcanic SO2, is rapidly being replaced by low-cost, miniature, ultraviolet (UV) spectrometers. We compared two of these new systems with a COSPEC by measuring SO2 column amounts at Kīlauea Volcano, Hawaii. The two systems, one calibrated using in-situ SO2 cells, and the other using a calibrated laboratory reference spectrum, employ similar spectrometer hardware, but different foreoptics and spectral retrieval algorithms. Accuracy, signal-to-noise, retrieval parameters, and precision were investigated for the two configurations of new miniature spectrometer. Measurements included traverses beneath the plumes from the summit and east rift zone of Kīlauea, and testing with calibration cells of known SO2 concentration. The results obtained from the different methods were consistent with each other, with <8% difference in estimated SO2 column amounts up to 800 ppm m. A further comparison between the COSPEC and one of the miniature spectrometer configurations, the ‘FLYSPEC’, spans an eight month period and showed agreement of measured emission rates to within 10% for SO2 column amounts up to 1,600 ppm m. The topic of measuring high SO2 burdens accurately is addressed for the Kīlauea measurements. In comparing the foreoptics, retrieval methods, and resultant implications for data quality, we aim to consolidate the various experiences to date, and improve the application and development of miniature spectrometer systems.`

Publication type Article
Publication Subtype Journal Article
Title Comparison of COSPEC and two miniature ultraviolet spectrometer systems for SO2 measurements using scattered sunlight
Series title Bulletin of Volcanology
DOI 10.1007/s00445-005-0026-5
Volume 68
Issue 4
Year Published 2006
Language English
Publisher Springer International
Contributing office(s) Volcano Hazards Program
Description 10 p.
First page 313
Last page 322
Online Only (Y/N) N
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
Additional publication details