Lava flow hazard at Fogo Volcano, Cape Verde, before and after the 2014–2015 eruption

Abstract. Lava flow simulations help to better understand volcanic hazards and may assist emergency preparedness at active volcanoes. We show that at Fogo Volcano, Cape Verde, such simulations can explain the 2014–2015 lava flow crisis and therefore provide a valuable base to better prepare for the inevitable next eruption. In a rapid disaster response effort, we conducted topographic mapping in the field and a satellite based remote sensing analysis. We produced the first topographic model of the 2014–2015 lava flows from combined Terrestrial Laser Scanner (TLS) and photogrammetric data. This high resolution topographic information facilitates lava flow volume estimates of 43.7 × 106 m3 (&plus;/−5.2 × 106 m3) from the vertical difference between pre- and post-eruptive topographies. Both, the pre-eruptive and updated Digital Elevation Models (DEMs) serve as the fundamental input parameters for lava flow simulations using the well-established DOWNFLOW algorithm. Based on thousands of simulations, we assess the lava flow hazard before and after the 2014–2015 eruption. We find that, although the lava flow hazard has changed significantly, it remains high at the locations of two villages that were destroyed during this eruption. This result is of particular importance as villagers have already started to rebuild the settlements. We also analyse satellite radar imagery acquired by the German TerraSAR-X (TSX) satellite to map lava flow emplacement over time. We obtain the lava flow boundaries every 6 days during the eruption which assists the interpretation and evaluation of the lava flow model performance. Based on this, we discuss how our study can help improving the general understanding of basaltic lava flow behavior. Our results highlight the fact that lava flow hazards change as a result of modifications of the local topography due to lava flow emplacement, which implies the need for up-to-date topographic information in order to assess lava flow hazards. We also emphasize that areas that were once overrun by lava flows are not necessarily "safer", even if local lava flow thicknesses exceed the average lava flow thickness. Our observations will be important for the next eruption of Fogo Volcano and have implications for future lava flow crises and disaster response efforts at basaltic volcanoes elsewhere in the world.

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Lava flow hazard at Fogo Volcano, Cabo Verde, before and after the 2014–2015 eruption

Natural Hazards and Earth System Science ◽

10.5194/nhess-16-1925-2016 ◽

2016 ◽

Vol 16 (8) ◽

pp. 1925-1951 ◽

Cited By ~ 24

Author(s):

Nicole Richter ◽

Massimiliano Favalli ◽

Elske de Zeeuw-van Dalfsen ◽

Alessandro Fornaciai ◽

Rui Manuel da Silva Fernandes ◽

...

Keyword(s):

Lava Flow ◽

Emergency Preparedness ◽

Disaster Response ◽

Flow Simulations ◽

Cabo Verde ◽

Topographic Information ◽

Lava Flow Hazard ◽

Before And After ◽

Lava Flow Emplacement ◽

Fogo Volcano

Abstract. Lava flow simulations help to better understand volcanic hazards and may assist emergency preparedness at active volcanoes. We demonstrate that at Fogo Volcano, Cabo Verde, such simulations can explain the 2014–2015 lava flow crisis and therefore provide a valuable base to better prepare for the next inevitable eruption. We conducted topographic mapping in the field and a satellite-based remote sensing analysis. We produced the first topographic model of the 2014–2015 lava flow from combined terrestrial laser scanner (TLS) and photogrammetric data. This high-resolution topographic information facilitates lava flow volume estimates of 43.7 ± 5.2 × 106 m3 from the vertical difference between pre- and posteruptive topographies. Both the pre-eruptive and updated digital elevation models (DEMs) serve as the fundamental input data for lava flow simulations using the well-established DOWNFLOW algorithm. Based on thousands of simulations, we assess the lava flow hazard before and after the 2014–2015 eruption. We find that, although the lava flow hazard has changed significantly, it remains high at the locations of two villages that were destroyed during this eruption. This result is of particular importance as villagers have already started to rebuild the settlements. We also analysed satellite radar imagery acquired by the German TerraSAR-X (TSX) satellite to map lava flow emplacement over time. We obtain the lava flow boundaries every 6 to 11 days during the eruption, which assists the interpretation and evaluation of the lava flow model performance. Our results highlight the fact that lava flow hazards change as a result of modifications of the local topography due to lava flow emplacement. This implies the need for up-to-date topographic information in order to assess lava flow hazards. We also emphasize that areas that were once overrun by lava flows are not necessarily safer, even if local lava flow thicknesses exceed the average lava flow thickness. Our observations will be important for the next eruption of Fogo Volcano and have implications for future lava flow crises and disaster response efforts at basaltic volcanoes elsewhere in the world.

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Supplementary material to "Lava flow hazard at Fogo Volcano, Cape Verde, before and after the 2014–2015 eruption"

10.5194/nhess-2016-81-supplement ◽

2016 ◽

Author(s):

Nicole Richter ◽

Massimiliano Favalli ◽

Elske de Zeeuw-van Dalfsen ◽

Alessandro Fornaciai ◽

Rui Manuel da Silva Fernandes ◽

...

Keyword(s):

Lava Flow ◽

Cape Verde ◽

Lava Flow Hazard ◽

Before And After ◽

Supplementary Material ◽

Fogo Volcano

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Optimizing barrier placement for lava flow hazard and risk mitigation

10.5194/egusphere-egu2020-8735 ◽

2020 ◽

Author(s):

Giuseppe Bilotta ◽

Annalisa Cappello ◽

Veronica Centorrino ◽

Claudia Corradino ◽

Gaetana Ganci ◽

...

Keyword(s):

Lava Flow ◽

Risk Mitigation ◽

Flow Direction ◽

Economic Loss ◽

Lava Flows ◽

Mount Etna ◽

Area Of Interest ◽

Lava Flow Hazard ◽

Mitigation Action ◽

The Impact

<p>Mitigating hazards when lava flows threaten infrastructure is one of the most challenging fields of volcanology, and has an immediate and practical impact on society. Lava flow hazard is determined by the probability of inundation, and essentially controlled by the topography of the area of interest. The most common actions of intervention for lava flow hazard mitigation are therefore the construction of artificial barriers and ditches that can control the flow direction and advancement speed. Estimating the effect a barrier or ditch can have on lava flow paths is non-trivial, but numerical modelling can provide a powerful tool by simulating the eruptive scenario and thus assess the effectiveness of the mitigation action. We present a numerical method for the design of optimal artificial barriers, in terms of location and geometric features, aimed at minimizing the impact of lava flows based on the spatial distribution of exposed elements. First, an exposure analysis collects information about elements at risk from different datasets: population per municipality, distribution of buildings, infrastructure, routes, gas and electricity networks, and land use; numerical simulations are used to compute the probability for these elements to be inundated by lava flows from a number of possible eruptive scenarios&#160; (hazard assessment) and computing the associated economic loss and potential destruction of key facilities (risk assessment). We then generate several intervention scenarios, defined by the location, orientation and geometry (width, length, thickness and even shape) of multiple barriers, and compute the corresponding variation in economic loss. Optimality of the barrier placement is thus considered as a minimization problem for the economic loss, controlled by the barrier placement and constrained by the associated costs. We demonstrate the operation of this system by using a retrospective analysis of some recent effusive eruptions at Mount Etna, Sicily.</p>

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Satellite and Ground Remote Sensing Techniques to Trace the Hidden Growth of a Lava Flow Field: The 2014-15 Effusive Eruption at Fogo Volcano (Cape Verde)

10.20944/preprints201806.0246.v1 ◽

2018 ◽

Author(s):

Sonia Calvari ◽

Gaetana Ganci ◽

Sónia Silva Victória ◽

Pedro A. Hernandez ◽

Nemesio Perez ◽

...

Keyword(s):

Remote Sensing ◽

Flow Field ◽

Lava Flow ◽

Rapid Expansion ◽

Lava Flows ◽

Key Factors ◽

Supply Rate ◽

Eruptive Fissure ◽

Lava Flow Field ◽

Fogo Volcano

Fogo volcano erupted in 2014-15 producing an extensive lava flow field in the summit caldera that destroyed two villages, Portela and Bangaeira. The eruption started with powerful explosive activity, lava fountains, and a substantial ash column accompanying the opening of an eruptive fissure. Lava flows spreading from the base of the eruptive fissure produced three arterial lava flows. By a week after the start of the eruption, a master lava tube had already developed within the eruptive fissure and along the arterial flow. In this paper, we analyze the emplacement processes on the basis of observations carried out directly on the lava flow field, remote sensing measurements carried out with a thermal camera, SO2 fluxes, and satellite images, in order to unravel the key factors leading to the development of lava tubes. These were responsible for the rapid expansion of lava for the ~7.9 km length of the flow field, as well as the destruction of the Portela and Bangaeira villages. The key factors leading to the development of tubes were the low topography and the steady magma supply rate along the arterial lava flow. Comparing time-averaged effusion rates (TADR) obtained from satellite and Supply Rate (SR) derived from SO2 flux data, we estimate the amount and timing of the lava flow field endogenous growth, with the aim of developing a tool that could be used for hazard assessment and risk mitigation at this and other volcanoes.

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Lava flow hazard modeling during the 2014-2015 Fogo eruption, Cape Verde

Journal of Geophysical Research Solid Earth ◽

10.1002/2015jb012666 ◽

2016 ◽

Vol 121 (4) ◽

pp. 2290-2303 ◽

Cited By ~ 21

Author(s):

Annalisa Cappello ◽

Gaetana Ganci ◽

Sonia Calvari ◽

Nemesio M. Pérez ◽

Pedro A. Hernández ◽

...

Keyword(s):

Lava Flow ◽

Cape Verde ◽

Hazard Modeling ◽

Lava Flow Hazard

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Distribution,14C chronology, and paleomagnetism of latest Pleistocene and Holocene lava flows at Haleakalā volcano, Island of Maui, Hawai‘i: A revision of lava flow hazard zones

Journal of Geophysical Research Atmospheres ◽

10.1029/2005jb003876 ◽

2006 ◽

Vol 111 (B5) ◽

pp. n/a-n/a ◽

Cited By ~ 12

Author(s):

David R. Sherrod ◽

Jonathan T. Hagstrum ◽

John P. McGeehin ◽

Duane E. Champion ◽

Frank A. Trusdell

Keyword(s):

Lava Flow ◽

Lava Flows ◽

Lava Flow Hazard

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Satellite and Ground Remote Sensing Techniques to Trace the Hidden Growth of a Lava Flow Field: The 2014–2015 Effusive Eruption at Fogo Volcano (Cape Verde)

Remote Sensing ◽

10.3390/rs10071115 ◽

2018 ◽

Vol 10 (7) ◽

pp. 1115 ◽

Cited By ~ 8

Author(s):

Sonia Calvari ◽

Gaetana Ganci ◽

Sónia Victória ◽

Pedro Hernandez ◽

Nemesio Perez ◽

...

Keyword(s):

Remote Sensing ◽

Flow Field ◽

Lava Flow ◽

Rapid Expansion ◽

Lava Flows ◽

Key Factors ◽

Supply Rate ◽

Eruptive Fissure ◽

Lava Flow Field ◽

Fogo Volcano

Fogo volcano erupted in 2014–2015 producing an extensive lava flow field in the summit caldera that destroyed two villages, Portela and Bangaeira. The eruption started with powerful explosive activity, lava fountains, and a substantial ash column accompanying the opening of an eruptive fissure. Lava flows spreading from the base of the eruptive fissure produced three arterial lava flows. By a week after the start of the eruption, a master lava tube had already developed within the eruptive fissure and along the arterial flow. In this paper, we analyze the emplacement processes based on observations carried out directly on the lava flow field, remote sensing measurements carried out with a thermal camera, SO2 fluxes, and satellite images, to unravel the key factors leading to the development of lava tubes. These were responsible for the rapid expansion of lava for the ~7.9 km length of the flow field, as well as the destruction of the Portela and Bangaeira villages. The key factors leading to the development of tubes were the low topography and the steady magma supply rate along the arterial lava flow. Comparing time-averaged discharge rates (TADR) obtained from satellite and Supply Rate (SR) derived from SO2 flux data, we estimate the amount and timing of the lava flow field endogenous growth, with the aim of developing a tool that could be used for hazard assessment and risk mitigation at this and other volcanoes.

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Anatomy of a Paroxysmal Lava Fountain at Etna Volcano: The Case of the 12 March 2021, Episode

Remote Sensing ◽

10.3390/rs13153052 ◽

2021 ◽

Vol 13 (15) ◽

pp. 3052

Author(s):

Sonia Calvari ◽

Alessandro Bonaccorso ◽

Gaetana Ganci

Keyword(s):

Lava Flow ◽

Ground Deformation ◽

Monitoring Network ◽

Lava Flows ◽

Etna Volcano ◽

Lava Fountain ◽

Eruptive Episode ◽

Lava Fountains ◽

Borehole Strainmeter ◽

Ash Plume

On 13 December 2020, Etna volcano entered a new eruptive phase, giving rise to a number of paroxysmal episodes involving increased Strombolian activity from the summit craters, lava fountains feeding several-km high eruptive columns and ash plumes, as well as lava flows. As of 2 August 2021, 57 such episodes have occurred in 2021, all of them from the New Southeast Crater (NSEC). Each paroxysmal episode lasted a few hours and was sometimes preceded (but more often followed) by lava flow output from the crater rim lasting a few hours. In this paper, we use remote sensing data from the ground and satellite, integrated with ground deformation data recorded by a high precision borehole strainmeter to characterize the 12 March 2021 eruptive episode, which was one of the most powerful (and best recorded) among that occurred since 13 December 2020. We describe the formation and growth of the lava fountains, and the way they feed the eruptive column and the ash plume, using data gathered from the INGV visible and thermal camera monitoring network, compared with satellite images. We show the growth of the lava flow field associated with the explosive phase obtained from a fixed thermal monitoring camera. We estimate the erupted volume of pyroclasts from the heights of the lava fountains measured by the cameras, and the erupted lava flow volume from the satellite-derived radiant heat flux. We compare all erupted volumes (pyroclasts plus lava flows) with the total erupted volume inferred from the volcano deflation recorded by the borehole strainmeter, obtaining a total erupted volume of ~3 × 106 m3 of magma constrained by the strainmeter. This volume comprises ~1.6 × 106 m3 of pyroclasts erupted during the lava fountain and 2.4 × 106 m3 of lava flow, with ~30% of the erupted pyroclasts being remobilized as rootless lava to feed the lava flows. The episode lasted 130 min and resulted in an eruption rate of ~385 m3 s−1 and caused the formation of an ash plume rising from the margins of the lava fountain that rose up to 12.6 km a.s.l. in ~1 h. The maximum elevation of the ash plume was well constrained by an empirical formula that can be used for prompt hazard assessment.

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Learning Outcome Measurement in Nurse Participants After Disaster Training

Disaster Medicine and Public Health Preparedness ◽

10.1017/dmp.2016.41 ◽

2016 ◽

Vol 10 (5) ◽

pp. 728-733

Author(s):

Sharon L. Farra ◽

Sherrill Smith ◽

Marie A Bashaw

Keyword(s):

Public Health ◽

Homeland Security ◽

Emergency Preparedness ◽

Disaster Response ◽

Outcome Measurement ◽

Disaster Medicine ◽

Learning Framework ◽

Before And After ◽

Disaster Training ◽

National Disaster

AbstractObjectiveThe National Disaster Health Consortium is an interprofessional disaster training program. Using the Hierarchical Learning Framework of Competency Sets in Disaster Medicine and Public Health, this program educates nurses and other professionals to provide competent care and leadership within the interprofessional team. This study examined outcomes of this training.MethodsTraining consisted of a combination of online and on-site training. Learning outcomes were measured by using the Emergency Preparedness Information Questionnaire (EPIQ) pre/post training and participant performance during live functional exercises with the use of rubrics based on Homeland Security Exercise and Evaluation principles.ResultsA total of 64 participants completed the EPIQ before and after training. The mean EPIQ pre-training score of 154 and mean post-training score of 81 (reverse-scored) was found to be statistically significant by paired t-test (P<0.001). Performance was evaluated in the areas of triage, re-triage, surge response, and sheltering. Greater than 90% of the exercise criteria were either met or partially met. Participants successfully achieved overall objectives in all scenarios.ConclusionsDisaster response requires nurses and other providers to function in interprofessional teams. Educational projects, like the National Disaster Health Consortium program, offer the potential to address the need for a standardized, interprofessional disaster training curriculum to promote positive outcomes. (Disaster Med Public Health Preparedness. 2016;page 1 of 6)

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