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U.S. Geological Survey, Cascades Volcano Observatory, Vancouver, USA
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- PublicationOpen AccessErratum to ‘A multidisciplinary effort to assign realistic source parameters to models of volcanic ash-cloud transport and dispersion during eruptions’ by Mastin et al. [J. Volcanol. Geotherm. Res. 188(2009)1–21](2010-04-01)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;Mastin, L. G.; U.S. Geological Survey, Cascades Volcano Observatory, Vancouver, USA ;Guffanti, M.; U.S. Geological Survey Reston, Virginia, USA ;Servranckx, R.; Canadian Meteorological Centre, Québec, Canada ;Webley, P.; Geophysical Institute, University of Alaska Fairbanks, USA ;Barsotti, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia ;Dean, K.; Geophysical Institute, University of Alaska Fairbanks, USA ;Durant, A.; Department of Earth Sciences, University of Bristol, England ;Ewert, J. W.; U.S. Geological Survey, Cascades Volcano Observatory, Vancouver, USA ;Neri, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia ;Rose, W. I.; Department of Geological and Engineering Sciences, Michigan Technological University, USA ;Schneider, D.; USGS Alaska Volcano Observatory, Anchorage, AK, USA ;Siebert, L.; Smithsonian Institution, Washington, D.C., USA ;Stunder, B.; Air Resources Laboratory, National Oceanic and Atmospheric Administration, Silver Spring, MD, USA ;Swanson, G.; National Oceanic and Atmospheric Administration, Camp Springs, MD, USA ;Tupper, A.; Bureau of Meteorology, Darwin, Casuarina, NT, Australia ;Volentik, A.; Department of Geology, University of South Florida, Tampa, FL, USA ;Waythomas, C. F.; USGS Alaska Volcano Observatory, Anchorage, AK, USA; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; no abstract165 107 - PublicationRestrictedResults of the eruptive column model inter-comparison study(2016)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;; ;; ; ; ; ;; ;; ; ;; ; ; ; ; ; ; ; ; ;This study compares and evaluates one-dimensional (1D) and three-dimensional (3D) numerical models of volcanic eruption columns in a set of different inter-comparison exercises. The exercises were designed as a blind test in which a set of common input parameters was given for two reference eruptions, representing a strong and a weak eruption column under different meteorological conditions. Comparing the results of the different models allows us to evaluate their capabilities and target areas for future improvement. Despite their different formulations, the 1D and 3D models provide reasonably consistent predictions of some of the key global descriptors of the volcanic plumes. Variability in plume height, estimated from the standard deviation of model predictions, is within ~20% for the weak plume and ~10% for the strong plume. Predictions of neutral buoyancy level are also in reasonably good agreement among the different models, with a standard deviation ranging from 9 to 19% (the latter for the weak plume in a windy atmosphere). Overall, these discrepancies are in the range of observational uncertainty of column height. However, there are important differences amongst models in terms of local properties along the plume axis, particularly for the strong plume. Our analysis suggests that the simpli- fied treatment of entrainment in 1D models is adequate to resolve the general behaviour of the weak plume. However, it is inadequate to capture complex features of the strong plume, such as large vortices, partial column collapse, or gravitational fountaining that strongly enhance entrainment in the lower atmosphere. We conclude that there is a need to more accurately quantify entrainment rates, improve the representation of plume radius, and incorporate the effects of column instability in future versions of 1D volcanic plume models.314 43 - PublicationRestrictedA multidisciplinary effort to assign realistic source parameters to models of volcanic ash-cloud transport and dispersion during eruptions(2009-09-30)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;Mastin, L. G.; U.S. Geological Survey, Cascades Volcano Observatory, Vancouver, WA 98683, USA ;Guffanti, M.; U.S. Geological Survey Reston, Virginia, USA ;Servranckx, R.; Canadian Meteorological Centre, Québec, Canada ;Webley, P. W.; Geophysical Institute, University of Alaska Fairbanks, USA ;Barsotti, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia ;Dean, K. G.; Geophysical Institute, University of Alaska Fairbanks, USA ;Durant, A. K.; Department of Earth Sciences, University of Bristol, England ;Ewert, J. W.; U.S. Geological Survey, Cascades Volcano Observatory, Vancouver, WA 98683, USA ;Neri, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia ;Rose, W. I.; Department of Geological and Engineering Sciences, Michigan Technological University, USA ;Schneider, D. J.; USGS Alaska Volcano Observatory, Anchorage, AK ;Siebert, L.; Smithsonian Institution, Washington, D.C., USA ;Stunder, B. J.; Air Resources Laboratory, National Oceanic and Atmospheric Administration, Silver Spring, MD ;Swanson, G.; National Oceanic and Atmospheric Administration, Camp Springs, MD, USA ;Tupper, A.; Bureau of Meteorology, Darwin, Casuarina, NT, Australia ;Volentik, A.; Department of Geology, University of South Florida, Tampa, FL, USA ;Waythomas, C. F.; USGS Alaska Volcano Observatory, Anchorage, AK; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; During volcanic eruptions, volcanic ash transport and dispersion models (VATDs) are used to forecast the location and movement of ash clouds over hours to days in order to define hazards to aircraft and to communities downwind. Those models use input parameters, called “eruption source parameters”, such as plume height H, mass eruption rate Ṁ, duration D, and the mass fraction m63 of erupted debris finer than about 4 or 63 μm, which can remain in the cloud for many hours or days. Observational constraints on the value of such parameters are frequently unavailable in the first minutes or hours after an eruption is detected. Moreover, observed plume height may change during an eruption, requiring rapid assignment of new parameters. This paper reports on a group effort to improve the accuracy of source parameters used by VATDs in the early hours of an eruption. We do so by first compiling a list of eruptions for which these parameters are well constrained, and then using these data to review and update previously studied parameter relationships. We find that the existing scatter in plots of H versus Ṁ yields an uncertainty within the 50% confidence interval of plus or minus a factor of four in eruption rate for a given plume height. This scatter is not clearly attributable to biases in measurement techniques or to well-recognized processes such as elutriation from pyroclastic flows. Sparse data on total grain-size distribution suggest that the mass fraction of fine debris m63 could vary by nearly two orders of magnitude between small basaltic eruptions ( 0.01) and large silicic ones (> 0.5). We classify eleven eruption types; four types each for different sizes of silicic and mafic eruptions; submarine eruptions; “brief” or Vulcanian eruptions; and eruptions that generate co-ignimbrite or co-pyroclastic flow plumes. For each eruption type we assign source parameters. We then assign a characteristic eruption type to each of the world's 1500 Holocene volcanoes. These eruption types and associated parameters can be used for ash-cloud modeling in the event of an eruption, when no observational constraints on these parameters are available.334 45 - PublicationOpen AccessNew Insights Into the Relationship Between Mass Eruption Rate and Volcanic Column Height Based On the IVESPA Data Set(2023)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;; ; ; ; ;Rapid and simple estimation of the mass eruption rate (MER) from column height is essential for real-time volcanic hazard management and reconstruction of past explosive eruptions. Using 134 eruptive events from the new Independent Volcanic Eruption Source Parameter Archive (IVESPA, v1.0), we explore empirical MER-height relationships for four measures of column height: spreading level, sulfur dioxide height, and top height from direct observations and as reconstructed from deposits. These relationships show significant differences and highlight limitations of empirical models currently used in operational and research applications. The roles of atmospheric stratification, wind, and humidity remain challenging to detect across the wide range of eruptive conditions spanned in IVESPA, ultimately resulting in empirical relationships outperforming analytical models that account for atmospheric conditions. This finding highlights challenges in constraining the MER-height relation using heterogeneous observations and empirical models, which reinforces the need for improved eruption source parameter data sets and physics-based models.81 15 - PublicationOpen AccessThe Independent Volcanic Eruption Source Parameter Archive (IVESPA, version 1.0): A new observational database to support explosive eruptive column model validation and development(2021)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;; ; ; ; ; ; ; ; ; ; ; ;Eruptive columnmodels are powerful tools for investigating the transport of volcanic gas and ash, reconstructing past explosive eruptions, and simulating future hazards. However, the evaluation of these models is challenging as it requires independent estimates of themainmodel inputs (e.g.mass eruption rate) and outputs (e.g. column height). There exists no database of independently estimated eruption source parameters (ESPs) that is extensive, standardized, maintained, and consensus-based. This paper introduces the Independent Volcanic Eruption Source Parameter Archive (IVESPA, ivespa.co.uk), a community effort endorsed by the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) Commission on Tephra HazardModelling.We compiled data for 134 explosive eruptive events, spanning the 1902-2016 period, with independent estimates of: i) total erupted mass of fall deposits; ii) duration; iii) eruption column height; and iv) atmospheric conditions. Crucially, we distinguish plume top versus umbrella spreading height, and the height of ash versus sulphur dioxide injection. All parameter values provided have been vetted independently by at least two experts. Uncertainties are quantified systematically, including flags to describe the degree of interpretation of the literature required for each estimate. IVESPA also includes a range of additional parameters such as total grain size distribution, eruption style, morphology of the plume (weak versus strong), and mass contribution from pyroclastic density currents, where available. We discuss the future developments and potential applications of IVESPA and make recommendations for reporting ESPs to maximize their usability across different applications. IVESPA covers an unprecedented range of ESPs and can therefore be used to evaluate and develop eruptive column models across a wide range of conditions using a standardized dataset.218 11