Dome Collapse Interaction With the Atmosphere

Barfucci, Giulia; Ripepe, Maurizio

doi:10.1029/2018gl078243

Cited by 2 publications

(2 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Array techniques are widespread in infrasound (see, e.g., Szuberla & Olson, 2004) and seismic (see, e.g., Rost & Thomas, 2002) monitoring. They have been used for the detection and monitoring of different kinds of gravity currents such as snow avalanches (Kogelnig et al, 2011;Marchetti et al, 2015;Ulivieri et al, 2011;Scott et al, 2007), pyroclastic flows (Barfucci & Ripepe, 2018;Ripepe et al, 2010), alpine glacier collapses (Preiswerk et al, 2016) and lahars (Johnson & Palma, 2015) but have yet to be applied to debris flows.…”

Section: Introductionmentioning

confidence: 99%

Infrasound Array Analysis of Debris Flow Activity and Implication for Early Warning

et al. 2019

Self Cite

View full text Add to dashboard Cite

Debris flows constitute a severe natural hazard and studies are performed to investigate triggering mechanisms and to identify and evaluate early warning systems. We present a seismoacoustic analysis of debris flow activity at Illgraben, Switzerland, with infrasound data collected with a small aperture array. Events are recorded as emergent signals of long duration, with seismic and infrasound amplitudes scaling with the flow discharge. The spectral content is stable and peaking at 8 Hz for the seismic and at 5 Hz for the infrasound that suggests two separate processes of elastic energy radiation, most likely bed‐load transport for the seismic and waves at the free surface for the infrasound. Although amplitude and frequency content of the infrasound signal are well within the processing limits, most of the signal is not showing any correlation among the array elements. We suggest that this is a consequence of the contribution of multiple sources of infrasound acting with variable amplitude and phase along the surface of the debris flow. At Illgraben, coherent infrasound is recorded only from fixed sources, corresponding to check dams within the channel. Here infrasound radiation is increased and the dams turn into predominant sources of energy. This allows to unambiguously identify the occurrence of debris flow at Illgraben with the infrasound array, from a remote and safe position and with a timing that is similar to the early warning system based on in‐channel sensors. This clearly shows how infrasound arrays could be used as an efficient early warning systems.

show abstract

Section: Introductionmentioning

confidence: 99%

Infrasound Array Analysis of Debris Flow Activity and Implication for Early Warning

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…Potentially, this mode might have been left out of the previous analysis because the filtering techniques in either instance deploy a bandpass filter with a lower cutoff frequency of 3 mHz. It is not uncommon for such a mode to follow acoustic dominated forcings, such as volcanos and earthquakes, and multiple low-frequency TIDs have beencan be identified in the hours preceding the eruption (Dautermann et al, 2009;Ripepe, et al, 2010;Matsumura et al 2011;De Angelis et al 2011;Barfucci et al 2018;Yue et al 2022). Althoughand the timing of this event coincides with the passage of the terminator line, caution has to be taken when tracing the origin of this mode.…”

Section: Gnss Observationsmentioning

confidence: 99%

Ionospheric Disturbances generated by the 2015 Calbuco Eruption: Comparison of GITM-R simulations and GNSS observations

Tyska

Deng

Zhang

et al. 2023

Preprint

View full text Add to dashboard Cite

Volcanic eruptions provide broad spectral forcing to the atmosphere and many previous studies have examined the IT disturbances caused by volcanic eruptions through both observations and modeling. Understanding the primary mechanisms that are relevant to explain the variety in waveform characteristics is still an important open question for the community. In this study, Global Navigation Satellite System (GNSS) Total Electron Content (TEC) data are analyzed and compared to simulations performed by the Global Ionosphere-Thermosphere Model with Local Mesh Refinement (GITM-R) for the first phase of the 2015 Calbuco eruption that occurred on 22 April. A simplified source representation and spectral acoustic-gravity wave (AGW) propagation model are used to specify the perturbation at the lower boundary of GITM-R at 100 km altitude. This modeling specification shows a good agreement with GNSS observations for some waveform characteristics such as travel/onset times and relative magnitudes. Most notably, GITM-R is able to reproduce the significance of AGWs as a function of radial distance from the vent, showing acoustic dominant forcing in the near field (<500 km) and gravity dominant forcing in the far-field (>500 km). The estimated apparent phase speeds from GITM-R simulations are consistent with observations with ~10% difference from observation for both acoustic wave packets and a trailing gravity mode. Relevance of the simplifications made in the lower atmosphere are then discussed and test changes to the assumed propagation structure, from direct propagation to ground-coupled propagation, show some improvement to the data-model comparison, especially the second acoustic wave-packet

show abstract

Dome Collapse Interaction With the Atmosphere

Cited by 2 publications

References 23 publications

Infrasound Array Analysis of Debris Flow Activity and Implication for Early Warning

Infrasound Array Analysis of Debris Flow Activity and Implication for Early Warning

Ionospheric Disturbances generated by the 2015 Calbuco Eruption: Comparison of GITM-R simulations and GNSS observations

Contact Info

Product

Resources

About