The Experts below are selected from a list of 174 Experts worldwide ranked by ideXlab platform
A J S Mcgonigle - One of the best experts on this subject based on the ideXlab platform.
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comparison of cospec and two miniature Ultraviolet Spectrometer systems for so 2 measurements using scattered sunlight
Bulletin of Volcanology, 2006Co-Authors: Tamar Elias, Clive Oppenheimer, A J S Mcgonigle, Jeff A Sutton, Keith A Horton, Harold Garbeil, V I Tsanev, Glyn WilliamsjonesAbstract: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.
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sulphur dioxide fluxes from mount etna vulcano and stromboli measured with an automated scanning Ultraviolet Spectrometer
Journal of Geophysical Research, 2003Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, A R Hayes, Marie Edmonds, Tommaso Caltabiano, Giuseppe Salerno, Mike Burton, Tamsin A MatherAbstract:We report here SO 2 flux measurements for the southern Italian volcanoes: Mount Etna, Vulcano, and Stromboli made in July 2002 from fixed positions, using an automated plume scanning technique. Spectral data were collected using a miniature Ultraviolet Spectrometer, and SO 2 column amounts were derived with a differential optical absorption spectroscopy evaluation routine. Scanning through the plume was enabled by a 45° turning mirror affixed to the shaft of a computer controlled stepper motor, so that scattered skylight from incremental angles within the horizon-to-horizon scans was reflected into the field of view of the Spectrometer. Each scan lasted ∼5 min and, by combining these data with wind speeds, average fluxes of 940, 14, and 280 Mg d - 1 were obtained for Etna, Vulcano, and Stromboli, respectively. For comparative purposes, conventional road and airborne traverses were also made using this Spectrometer, yielding fluxes of 850, 17, and 210 Mg d - 1 . The automated scanning technique has the advantage of obviating the need for time-consuming traverses underneath the plume and is well suited for longer-term telemetered deployments to provide sustained high time resolution flux data.
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sulphur dioxide fluxes from mount etna vulcano and stromboli measured with an automated scanning Ultraviolet Spectrometer
Journal of Geophysical Research, 2003Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, A R Hayes, Marie Edmonds, Tommaso Caltabiano, Giuseppe Salerno, Mike Burton, T. A. MatherAbstract:Gruppo Nazionale per Vulcanolgia (GNV), the EC 5th Framework project ‘‘MULTIMO’’, and NERC grant GR9/04655
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a miniaturised Ultraviolet Spectrometer for remote sensing of so2 fluxes a new tool for volcano surveillance
Journal of Volcanology and Geothermal Research, 2003Co-Authors: Clive Oppenheimer, Bo Galle, A J S Mcgonigle, Marie Edmonds, A Geyer, L A HorrocksAbstract:Abstract For 30 years, the correlation Spectrometer (COSPEC) has been the principal tool for remote monitoring of volcanic SO 2 fluxes. During this time, the instrument has played a prominent role in volcanic hazard assessment. COSPEC data also underpin estimates of the global volcanic SO 2 flux to the atmosphere. Though innovative for its time, COSPEC is now outdated in several respects. Here we report the first measurements with a potential replacement, using a low cost, miniature, Ultraviolet fibre-optic differential optical absorption Spectrometer (mini-DOAS). Field experiments were conducted at Masaya Volcano (Nicaragua) and Soufriere Hills Volcano (Montserrat). The mini-DOAS was operated from a road vehicle and helicopter, and from a fixed position on the ground, indicating fluxes of ∼4 and 1 kg s −1 at Masaya Volcano and Soufriere Hills Volcano, respectively. Side-by-side observations with a COSPEC on Montserrat indicate a comparable sensitivity but the mini-DOAS offers several advantages, including the collection of broadband Ultraviolet spectra. It has immense potential for geochemical surveillance at volcanoes worldwide.
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walking traverse and scanning doas measurements of volcanic gas emission rates
Geophysical Research Letters, 2002Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, T. A. Mather, D M PyleAbstract:[1] We report here the first measurements of volcanic SO2 fluxes obtained on foot, using a miniature Ultraviolet Spectrometer. Our measurements, based on differential optical absorption spectroscopy (DOAS), were performed ≈1 km from the summit of Masaya volcano (Nicaragua) in December 2001, and yielded a mean SO2 emission rate of 4 kg s−1, comparable with a set of contemporaneous measurements obtained by road vehicle traverses (average 6 kg s−1). SO2 flux estimates (average 4 kg s−1) were also obtained from a fixed position by scanning the plume. This range of fluxes confirms an apparent decrease in gas output from the volcano since 2000. The portability and ease of use of the Spectrometer offer considerable scope for routine measurements of SO2 emissions from volcanoes, especially where road access or opportunities for airborne campaigns are limited. These approaches can be readily extended to monitor other sources and gases.
Bo Galle - One of the best experts on this subject based on the ideXlab platform.
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sulphur dioxide fluxes from mount etna vulcano and stromboli measured with an automated scanning Ultraviolet Spectrometer
Journal of Geophysical Research, 2003Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, A R Hayes, Marie Edmonds, Tommaso Caltabiano, Giuseppe Salerno, Mike Burton, Tamsin A MatherAbstract:We report here SO 2 flux measurements for the southern Italian volcanoes: Mount Etna, Vulcano, and Stromboli made in July 2002 from fixed positions, using an automated plume scanning technique. Spectral data were collected using a miniature Ultraviolet Spectrometer, and SO 2 column amounts were derived with a differential optical absorption spectroscopy evaluation routine. Scanning through the plume was enabled by a 45° turning mirror affixed to the shaft of a computer controlled stepper motor, so that scattered skylight from incremental angles within the horizon-to-horizon scans was reflected into the field of view of the Spectrometer. Each scan lasted ∼5 min and, by combining these data with wind speeds, average fluxes of 940, 14, and 280 Mg d - 1 were obtained for Etna, Vulcano, and Stromboli, respectively. For comparative purposes, conventional road and airborne traverses were also made using this Spectrometer, yielding fluxes of 850, 17, and 210 Mg d - 1 . The automated scanning technique has the advantage of obviating the need for time-consuming traverses underneath the plume and is well suited for longer-term telemetered deployments to provide sustained high time resolution flux data.
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sulphur dioxide fluxes from mount etna vulcano and stromboli measured with an automated scanning Ultraviolet Spectrometer
Journal of Geophysical Research, 2003Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, A R Hayes, Marie Edmonds, Tommaso Caltabiano, Giuseppe Salerno, Mike Burton, T. A. MatherAbstract:Gruppo Nazionale per Vulcanolgia (GNV), the EC 5th Framework project ‘‘MULTIMO’’, and NERC grant GR9/04655
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a miniaturised Ultraviolet Spectrometer for remote sensing of so2 fluxes a new tool for volcano surveillance
Journal of Volcanology and Geothermal Research, 2003Co-Authors: Clive Oppenheimer, Bo Galle, A J S Mcgonigle, Marie Edmonds, A Geyer, L A HorrocksAbstract:Abstract For 30 years, the correlation Spectrometer (COSPEC) has been the principal tool for remote monitoring of volcanic SO 2 fluxes. During this time, the instrument has played a prominent role in volcanic hazard assessment. COSPEC data also underpin estimates of the global volcanic SO 2 flux to the atmosphere. Though innovative for its time, COSPEC is now outdated in several respects. Here we report the first measurements with a potential replacement, using a low cost, miniature, Ultraviolet fibre-optic differential optical absorption Spectrometer (mini-DOAS). Field experiments were conducted at Masaya Volcano (Nicaragua) and Soufriere Hills Volcano (Montserrat). The mini-DOAS was operated from a road vehicle and helicopter, and from a fixed position on the ground, indicating fluxes of ∼4 and 1 kg s −1 at Masaya Volcano and Soufriere Hills Volcano, respectively. Side-by-side observations with a COSPEC on Montserrat indicate a comparable sensitivity but the mini-DOAS offers several advantages, including the collection of broadband Ultraviolet spectra. It has immense potential for geochemical surveillance at volcanoes worldwide.
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walking traverse and scanning doas measurements of volcanic gas emission rates
Geophysical Research Letters, 2002Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, T. A. Mather, D M PyleAbstract:[1] We report here the first measurements of volcanic SO2 fluxes obtained on foot, using a miniature Ultraviolet Spectrometer. Our measurements, based on differential optical absorption spectroscopy (DOAS), were performed ≈1 km from the summit of Masaya volcano (Nicaragua) in December 2001, and yielded a mean SO2 emission rate of 4 kg s−1, comparable with a set of contemporaneous measurements obtained by road vehicle traverses (average 6 kg s−1). SO2 flux estimates (average 4 kg s−1) were also obtained from a fixed position by scanning the plume. This range of fluxes confirms an apparent decrease in gas output from the volcano since 2000. The portability and ease of use of the Spectrometer offer considerable scope for routine measurements of SO2 emissions from volcanoes, especially where road access or opportunities for airborne campaigns are limited. These approaches can be readily extended to monitor other sources and gases.
Clive Oppenheimer - One of the best experts on this subject based on the ideXlab platform.
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comparison of cospec and two miniature Ultraviolet Spectrometer systems for so 2 measurements using scattered sunlight
Bulletin of Volcanology, 2006Co-Authors: Tamar Elias, Clive Oppenheimer, A J S Mcgonigle, Jeff A Sutton, Keith A Horton, Harold Garbeil, V I Tsanev, Glyn WilliamsjonesAbstract: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.
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sulphur dioxide fluxes from mount etna vulcano and stromboli measured with an automated scanning Ultraviolet Spectrometer
Journal of Geophysical Research, 2003Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, A R Hayes, Marie Edmonds, Tommaso Caltabiano, Giuseppe Salerno, Mike Burton, Tamsin A MatherAbstract:We report here SO 2 flux measurements for the southern Italian volcanoes: Mount Etna, Vulcano, and Stromboli made in July 2002 from fixed positions, using an automated plume scanning technique. Spectral data were collected using a miniature Ultraviolet Spectrometer, and SO 2 column amounts were derived with a differential optical absorption spectroscopy evaluation routine. Scanning through the plume was enabled by a 45° turning mirror affixed to the shaft of a computer controlled stepper motor, so that scattered skylight from incremental angles within the horizon-to-horizon scans was reflected into the field of view of the Spectrometer. Each scan lasted ∼5 min and, by combining these data with wind speeds, average fluxes of 940, 14, and 280 Mg d - 1 were obtained for Etna, Vulcano, and Stromboli, respectively. For comparative purposes, conventional road and airborne traverses were also made using this Spectrometer, yielding fluxes of 850, 17, and 210 Mg d - 1 . The automated scanning technique has the advantage of obviating the need for time-consuming traverses underneath the plume and is well suited for longer-term telemetered deployments to provide sustained high time resolution flux data.
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sulphur dioxide fluxes from mount etna vulcano and stromboli measured with an automated scanning Ultraviolet Spectrometer
Journal of Geophysical Research, 2003Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, A R Hayes, Marie Edmonds, Tommaso Caltabiano, Giuseppe Salerno, Mike Burton, T. A. MatherAbstract:Gruppo Nazionale per Vulcanolgia (GNV), the EC 5th Framework project ‘‘MULTIMO’’, and NERC grant GR9/04655
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a miniaturised Ultraviolet Spectrometer for remote sensing of so2 fluxes a new tool for volcano surveillance
Journal of Volcanology and Geothermal Research, 2003Co-Authors: Clive Oppenheimer, Bo Galle, A J S Mcgonigle, Marie Edmonds, A Geyer, L A HorrocksAbstract:Abstract For 30 years, the correlation Spectrometer (COSPEC) has been the principal tool for remote monitoring of volcanic SO 2 fluxes. During this time, the instrument has played a prominent role in volcanic hazard assessment. COSPEC data also underpin estimates of the global volcanic SO 2 flux to the atmosphere. Though innovative for its time, COSPEC is now outdated in several respects. Here we report the first measurements with a potential replacement, using a low cost, miniature, Ultraviolet fibre-optic differential optical absorption Spectrometer (mini-DOAS). Field experiments were conducted at Masaya Volcano (Nicaragua) and Soufriere Hills Volcano (Montserrat). The mini-DOAS was operated from a road vehicle and helicopter, and from a fixed position on the ground, indicating fluxes of ∼4 and 1 kg s −1 at Masaya Volcano and Soufriere Hills Volcano, respectively. Side-by-side observations with a COSPEC on Montserrat indicate a comparable sensitivity but the mini-DOAS offers several advantages, including the collection of broadband Ultraviolet spectra. It has immense potential for geochemical surveillance at volcanoes worldwide.
-
walking traverse and scanning doas measurements of volcanic gas emission rates
Geophysical Research Letters, 2002Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, T. A. Mather, D M PyleAbstract:[1] We report here the first measurements of volcanic SO2 fluxes obtained on foot, using a miniature Ultraviolet Spectrometer. Our measurements, based on differential optical absorption spectroscopy (DOAS), were performed ≈1 km from the summit of Masaya volcano (Nicaragua) in December 2001, and yielded a mean SO2 emission rate of 4 kg s−1, comparable with a set of contemporaneous measurements obtained by road vehicle traverses (average 6 kg s−1). SO2 flux estimates (average 4 kg s−1) were also obtained from a fixed position by scanning the plume. This range of fluxes confirms an apparent decrease in gas output from the volcano since 2000. The portability and ease of use of the Spectrometer offer considerable scope for routine measurements of SO2 emissions from volcanoes, especially where road access or opportunities for airborne campaigns are limited. These approaches can be readily extended to monitor other sources and gases.
Marie Edmonds - One of the best experts on this subject based on the ideXlab platform.
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sulphur dioxide fluxes from mount etna vulcano and stromboli measured with an automated scanning Ultraviolet Spectrometer
Journal of Geophysical Research, 2003Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, A R Hayes, Marie Edmonds, Tommaso Caltabiano, Giuseppe Salerno, Mike Burton, Tamsin A MatherAbstract:We report here SO 2 flux measurements for the southern Italian volcanoes: Mount Etna, Vulcano, and Stromboli made in July 2002 from fixed positions, using an automated plume scanning technique. Spectral data were collected using a miniature Ultraviolet Spectrometer, and SO 2 column amounts were derived with a differential optical absorption spectroscopy evaluation routine. Scanning through the plume was enabled by a 45° turning mirror affixed to the shaft of a computer controlled stepper motor, so that scattered skylight from incremental angles within the horizon-to-horizon scans was reflected into the field of view of the Spectrometer. Each scan lasted ∼5 min and, by combining these data with wind speeds, average fluxes of 940, 14, and 280 Mg d - 1 were obtained for Etna, Vulcano, and Stromboli, respectively. For comparative purposes, conventional road and airborne traverses were also made using this Spectrometer, yielding fluxes of 850, 17, and 210 Mg d - 1 . The automated scanning technique has the advantage of obviating the need for time-consuming traverses underneath the plume and is well suited for longer-term telemetered deployments to provide sustained high time resolution flux data.
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sulphur dioxide fluxes from mount etna vulcano and stromboli measured with an automated scanning Ultraviolet Spectrometer
Journal of Geophysical Research, 2003Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, A R Hayes, Marie Edmonds, Tommaso Caltabiano, Giuseppe Salerno, Mike Burton, T. A. MatherAbstract:Gruppo Nazionale per Vulcanolgia (GNV), the EC 5th Framework project ‘‘MULTIMO’’, and NERC grant GR9/04655
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a miniaturised Ultraviolet Spectrometer for remote sensing of so2 fluxes a new tool for volcano surveillance
Journal of Volcanology and Geothermal Research, 2003Co-Authors: Clive Oppenheimer, Bo Galle, A J S Mcgonigle, Marie Edmonds, A Geyer, L A HorrocksAbstract:Abstract For 30 years, the correlation Spectrometer (COSPEC) has been the principal tool for remote monitoring of volcanic SO 2 fluxes. During this time, the instrument has played a prominent role in volcanic hazard assessment. COSPEC data also underpin estimates of the global volcanic SO 2 flux to the atmosphere. Though innovative for its time, COSPEC is now outdated in several respects. Here we report the first measurements with a potential replacement, using a low cost, miniature, Ultraviolet fibre-optic differential optical absorption Spectrometer (mini-DOAS). Field experiments were conducted at Masaya Volcano (Nicaragua) and Soufriere Hills Volcano (Montserrat). The mini-DOAS was operated from a road vehicle and helicopter, and from a fixed position on the ground, indicating fluxes of ∼4 and 1 kg s −1 at Masaya Volcano and Soufriere Hills Volcano, respectively. Side-by-side observations with a COSPEC on Montserrat indicate a comparable sensitivity but the mini-DOAS offers several advantages, including the collection of broadband Ultraviolet spectra. It has immense potential for geochemical surveillance at volcanoes worldwide.
Tamsin A Mather - One of the best experts on this subject based on the ideXlab platform.
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sulphur dioxide fluxes from mount etna vulcano and stromboli measured with an automated scanning Ultraviolet Spectrometer
Journal of Geophysical Research, 2003Co-Authors: A J S Mcgonigle, Clive Oppenheimer, Bo Galle, A R Hayes, Marie Edmonds, Tommaso Caltabiano, Giuseppe Salerno, Mike Burton, Tamsin A MatherAbstract:We report here SO 2 flux measurements for the southern Italian volcanoes: Mount Etna, Vulcano, and Stromboli made in July 2002 from fixed positions, using an automated plume scanning technique. Spectral data were collected using a miniature Ultraviolet Spectrometer, and SO 2 column amounts were derived with a differential optical absorption spectroscopy evaluation routine. Scanning through the plume was enabled by a 45° turning mirror affixed to the shaft of a computer controlled stepper motor, so that scattered skylight from incremental angles within the horizon-to-horizon scans was reflected into the field of view of the Spectrometer. Each scan lasted ∼5 min and, by combining these data with wind speeds, average fluxes of 940, 14, and 280 Mg d - 1 were obtained for Etna, Vulcano, and Stromboli, respectively. For comparative purposes, conventional road and airborne traverses were also made using this Spectrometer, yielding fluxes of 850, 17, and 210 Mg d - 1 . The automated scanning technique has the advantage of obviating the need for time-consuming traverses underneath the plume and is well suited for longer-term telemetered deployments to provide sustained high time resolution flux data.