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Todo se oscureció: uniting remote sensing observations and human experiences to understand recent eruptive activity of Volcán de Fuego, Guatemala

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This thesis presents an interdisciplinary case study of the active Volcán de Fuego in southern Guatemala to examine: (1) the physical behaviours and volcanic hazards that characterize eruptions occurring in recent years, and (2) the factors that influence local residents’ decision to evacuate from these eruptions. The thesis presents different answers to these issues depending on the data sources studied: satellite observations, geophysical and gas timeseries, and observations of and interviews with local residents and authorities. The thesis begins by presenting Fuego as an ideal subject for an interdisciplinary volcanology PhD, and establishes the philosophical positions and methodological approaches that were necessary to consider in order to undertake both physical and social science research within this PhD. The first results of this thesis are satellite observations of Fuego’s activity between January 2015 and June 2018. These observations, supplemented by other data, identify a new eruptive regime characterized by frequent explosive eruptions ("paroxysms") consistently preceded by lava flow effusion. Thresholds for determining eruption are debated. Physical results are juxtaposed with qualitative narratives of previous eruptions of Fuego and evacuations of communities as told by both authorities and local residents of rural communities around the volcano. These narratives reveal that an eruption at Fuego is not a consistent phenomenon, but is experienced differently by different observers based on their previous experiences, knowledge, resources, and priorities. Finally, quantitative and qualitative data are integrated through analysis of timeframes of eruption and response for several recent eruptions. Quantitative timescales and their qualitative counterpart, timelines, provide detailed chronologies of times and uncertainties involved in forecasting eruptions of Fuego and of deciding, warning, responding to, and evacuating from eruption. Ultimately, this thesis concludes that the lives of local residents cannot be reliably protected from hazards of Fuego without integration of the monitoring and risk mitigation efforts of INSIVUMEH and CONRED. This integration mirrors that of physical and social drivers of volcanic risk explored within this work. This thesis demonstrates the value of integrating physical and social research methods in a single interdisciplinary project, and contributes to volcanological literature with findings that volcanic risk is both spatially and temporally variable around a single volcano.
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... However, national media later highlighted the disconnect between these authorities supposedly fulfilling their responsibilities and the high death toll. In partic-Fireside tales: Volcán de Fuego Naismith et al., 2020 ular, media focussed on the different fates of geographically close communities: why did the private golf resort of La Reunión successfully evacuate, yet Los Lotes, two kilometres further south, suffer such extensive human loss [Tobar 2018]?. This question relates to the larger issue of the ability and willingness of communities to evacuate from eruptive crisis. ...
... The most effective action to mitigate risk to life from most volcanic hazards is evacuation. The decision Fireside tales: Volcán de Fuego Naismith et al., 2020 to evacuate is often difficult to make because all choices may have negative consequences. An individual may decide to reduce personal risk when an eruption reaches its climax. ...
... Therefore, interviews provided an opportunity for better understanding of "[a] phenomenon about which little is yet known . . . to gain more in-depth information that may be difficult to convey quantitatively" [Hoepfl 1997]. Our paper is published from the results of the lead author's thesis, which includes theoretical assumptions and philosophical stance involved in her research [Naismith 2020]. ...
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Volcán de Fuego (Guatemala) is an active stratovolcano capable of large (VEI~>2) explosive eruptions like that of 3rd June 2018, which triggered pyroclastic flows that devastated the community of San Miguel Los Lotes and caused hundreds of fatalities and severe long-term socioeconomic impacts. Future volcanic risk mitigation efforts are likely to involve temporary evacuation of local communities, the success of which requires cooperation between locals, scientists, and decision-makers. However, locals' experiences of eruptive activity, and how these experiences influence their responses to evacuation, have not been studied in detail. In 2019 we conducted an investigation of these themes through qualitative research methods involving semi-structured interviews that focussed on direct experience as opposed to volcanic risk perception. We found substantial differences between scientists' and locals' observations of Fuego's activity. Furthermore, a clear disparity emerged between communities on Fuego's west and east flanks in terms of direct prior experience of eruptions and communication with authorities. These findings have serious implications for future evacuation efforts at Fuego and at other highly populated active volcanoes.
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