Guidelines for volcano-observatory operations during crises: recommendations from the 2019 volcano observatory best practices meeting

In November 2019, the fourth Volcano Observatory Best Practices workshop was held in Mexico City as a series of talks, discussions, and panels. Volcanologists from around the world offered suggestions for ways to optimize volcano-observatory crisis operations. By crisis, we mean unrest that may or may not lead to eruption, the eruption itself, or its aftermath, all of which require analysis and communications by the observatory. During a crisis, the priority of the observatory should be to acquire, process, analyze, and interpret data in a timely manner. A primary goal is to communicate effectively with the authorities in charge of civil protection. Crisis operations should rely upon exhaustive planning in the years prior to any actual unrest or eruptions. Ideally, nearly everything that observatories do during a crisis should be envisioned, prepared, and practiced prior to the actual event. Pre-existing agreements and exercises with academic and government collaborators will minimize confusion about roles and responsibilities. In the situation where planning is unfinished, observatories should prioritize close ties and communications with the land and civil-defense authorities near the most threatening volcanoes.To a large extent, volcanic crises become social crises, and any volcano observatory should have a communication strategy, a lead communicator, regular status updates, and a network of colleagues outside the observatory who can provide similar messaging to a public that desires consistent and authoritative information. Checklists permit tired observatory staff to fulfill their duties without forgetting key communications, data streams, or protocols that need regular fulfilment (Bretton et al. Volcanic Unrest. Advances in Volcanology, 2018; Newhall et al. Bull Volcanol 64:3–20, 2020). Observatory leaders need to manage staff workload to prevent exhaustion and ensure that expertise is available as needed. Event trees and regular group discussions encourage multi-disciplinary thinking, consideration of disparate viewpoints, and documentation of all group decisions and consensus. Though regulations, roles and responsibilities differ around the world, scientists can justify their actions in the wake of an eruption if they document their work, are thoughtful and conscientious in their deliberations, and carry out protocols and procedures developed prior to volcanic unrest. This paper also contains six case studies of volcanic eruptions or observatory actions that illustrate some of the topics discussed herein. Specifically, we discuss Ambae (Vanuatu) in 2017–2018, Kīlauea (USA) in 2018, Etna (Italy) in 2018, Bárðarbunga (Iceland) in 2014, Cotopaxi (Ecuador) in 2015, and global data sharing to prepare for eruptions at Nyiragongo (Democratic Republic of Congo). A Spanish-language version of this manuscript is provided as Additional file 1.

Reappraisal of gap analysis for effusive crises at Piton de la Fournaise

Effective and rapid effusive crisis response is necessary to mitigate the risks associated with lava flows that could threaten or inundate inhabited or visited areas. At Piton de la Fournaise (La Réunion, France), well-established protocols between Observatoire Volcanologique du Piton de la Fournaise – Institut de Physique du Globe de Paris (OVPF-IPGP) and civil protection, and between scientists of a multinational array of institutes, allow effective tracking of eruptive crises and hazard management embracing all stakeholders. To assess the outstanding needs for such responses Tsang and Lindsay (J Appl Volcanol 9:9, 2020) applied a gap analysis to assess research gaps in terms of preparedness, response and recovery at 11 effusive centers, including Piton de la Fournaise. For Piton de la Fournaise, their gap analysis implied widespread gaps in the state of knowledge. However, their work relied on incomplete and erroneous data and methods, resulting in a gap analysis that significantly underrepresented this state of knowledge. We thus here re-build a correct database for Piton de la Fournaise, properly define the scope of an appropriate gap analysis, and provide a robust gap analysis, finding that there are, actually, very few gaps for Piton de la Fournaise. This is a result of the existence of a great quantity of published work in the peer-reviewed literature, as well as frequent reports documenting event impact in the local press and observatory reports. At Piton de la Fournaise, this latter (observatory-based) resource is largely due to the efforts of OVPF-IPGP who have a wealth of experience having responded to 81 eruptions since its creation in 1979 through the end of September 2021.Although welcome and necessary, especially if it is made by a group of scientists outside the local management of the volcanic risk (i.e., a neutral group), such gap analysis need to be sure to fully consider all available peer-reviewed literature, as well as newspaper reports, observatory releases and non-peer-reviewed eruption reports, so as to be complete and correct. Fundamentally, such an analysis needs to consider the information collected and produced by the volcano observatory charged with handling surveillance operations and reporting duties to civil protection for the volcano under analysis. As a very minimum, to ensure that a necessarily comprehensive and complete treatment of the scientific literature has been completed, we recommend that a third party expert, who is a recognized specialist in terms of research at the site considered, reviews and checks the material used for the gap analysis before final release of recommendations.

Hazard assessment studies and multiparametric volcano monitoring developed by the Instituto Geológico, Minero y Metalúrgico in Peru

Urban development in the areas surrounding active volcanoes has led to increasing risks in southern Peru. In order to evaluate the hazard, the Instituto Geológico, Minero y Metalúrgico (INGEMMET) created a Volcano Observatory (OVI) to carry out detailed geological investigations to understand eruption histories and provide volcanic hazard maps. The generation of geological information on volcanoes has allowed the identification of scenarios and zoning of potentially impacted areas. This information has also allowed OVI to implement surveillance networks giving priority to the volcanoes that pose the greatest risk to the population, infrastructure, and economic activities. Since 2006, OVI has been running volcanic monitoring networks with a multidisciplinary approach, improving real-time transmission, and making timely forecasts. Based on geological information and the risk posed by the volcanoes, the greatest efforts have been made to monitor Sabancaya, Misti, Ubinas, and Ticsani volcanoes. Following the order of priorities, monitoring of Coropuna, Huaynaputina, Tutupaca and, Yucamane volcanoes has also been developed. In addition, OVI carries out routine education activities and diffusion of information that serve to manage volcanic risk in Peru. El desarrollo urbano en zonas aledañas a volcanes activos ha conllevado a la generación de riesgos cada vez mayores en el sur del Perú. Con la finalidad de evaluar el peligro, el Instituto Geológico, Minero y Metalúrgico (INGEMMET) creó un observatorio vulcanológico (OVI) para realizar estudios geológicos detallados que permitan conocer las historias eruptivas y elaborar mapas de peligros volcánicos. La generación de información geológica sobre los volcanes ha permitido la identificación de escenarios y la zonificación de áreas con potencial a ser afectadas. Esta información también ha permitido al OVI implementar sus redes de monitoreo priorizando los volcanes que representan mayor riesgo para la población, la infraestructura y las actividades económicas. Desde el año 2006, el OVI viene implementando redes de vigilancia volcánica con un enfoque multidisciplinario, mejorando la transmisión en tiempo real y realizando pronósticos oportunos. En base a la información geológica y el nivel de riesgo de los volcanes, se han puesto los mayores esfuerzos en monitorear los volcanes Sabancaya, Misti, Ubinas y Ticsani. Siguiendo el orden de prioridades, el OVI ha comenzado, también, el monitoreo de los volcanes Coropuna, Huaynaputina, Tutupaca y Yucamane. Además, el observatorio desarrolla actividades permanentes de educación y difusión de la información que sirven a la gestión del riesgo volcánico en el Perú.

Towards the development of the first permanent volcano observatory in Argentina

Argentina is a country that presents a complex situation regarding volcanic risk, where a total of 38 volcanoes are considered active. Although Argentina has no major cities close to these volcanoes, the continuous increase in economic activity and infrastructure near the Andean Codillera will increase exposure to volcano hazards in the future. Further, volcanic activity on the border between Argentina and Chile poses a unique challenge in relation to volcano monitoring and the management of volcanic emergencies. Additionally, due to atmospheric circulation patterns in the region (from West to East), Argentina is exposed to ashfall and ash dispersion from frequent explosive eruptions from Chilean volcanoes. Considering this, the Servicio Geológico Minero Argentino (SEGEMAR) decided to create and implement a Volcanic Threat Assessment Program, which includes the creation of the the first permanent volcano observatory for the country, the Observatorio Argentino de Vigilancia Volcánica (OAVV). Previously the Decepcion Island volcano observatory was created as a collaboration between the Instituto Antártico Argentino (IAA) and the Museo Nacional de Ciencias Naturales (MNCN) from the Consejo Superior de Investigaciones Científicas (CSIC). Argentina es un país que presenta una compleja situación con respecto al riesgo volcánico, donde un total de 38 volcanes son considerados activos. Aunque Argentina no tiene ciudades importantes cerca de estos volcanes, el continuo incremento de la actividad económica y la infraestructura cerca de la Cordillera de los Andes, generará en el futuro un aumento en la exposición a estos peligros. Además, la actividad volcánica en la frontera entre Argentina y Chile constituye un desafío único en relación con el monitoreo de volcanes y la gestión de emergencias volcánicas. Adicionalmente, debido a los patrones de circulación atmosférica en la región (desde el oeste hacia el este), Argentina está expuesta a la caída y dispersión de cenizas de las frecuentes erupciones explosivas de volcanes chilenos. Teniendo esto en cuenta, el Servicio Geológico Minero Argentino (SEGEMAR) decidió crear e implementar un programa de evaluación de amenazas volcánicas, que incluye, la creación del primer observatorio permanente de volcanes para el país, el Observatorio Argentino de Vigilancia Volcánica (OAVV). Previamente, el Observatorio Volcanológico de la Isla Decepción fue creado como una colaboración entre el Instituto Antártico Argentino (IAA) y el Museo Nacional de Ciencias Naturales (MNCN) del Consejo Superior de Investigaciones Científicas de España (CSIC).

Day–Night Monitoring of Volcanic SO2 and Ash Clouds for Aviation Avoidance at Northern Polar Latitudes

We describe NASA’s Applied Sciences Disasters Program, which is a collaborative project between the Direct Readout Laboratory (DRL), ozone processing team, Jet Propulsion Laboratory, Geographic Information Network of Alaska (GINA), and Finnish Meteorological Institute (FMI), to expedite the processing and delivery of direct readout (DR) volcanic ash and sulfur dioxide (SO2) satellite data. We developed low-latency quantitative retrievals of SO2 column density from the solar backscattered ultraviolet (UV) measurements using the Ozone Mapping and Profiler Suite (OMPS) spectrometers as well as the thermal infrared (TIR) SO2 and ash indices using Visible Infrared Imaging Radiometer Suite (VIIRS) instruments, all flying aboard US polar-orbiting meteorological satellites. The VIIRS TIR indices were developed to address the critical need for nighttime coverage over northern polar regions. Our UV and TIR SO2 and ash software packages were designed for the DRL’s International Planetary Observation Processing Package (IPOPP); IPOPP runs operationally at GINA and FMI stations in Fairbanks, Alaska, and Sodankylä, Finland. The data are produced within 30 min of satellite overpasses and are distributed to the Alaska Volcano Observatory and Anchorage Volcanic Ash Advisory Center. FMI receives DR data from GINA and posts composite Arctic maps for ozone, volcanic SO2, and UV aerosol index (UVAI, proxy for ash or smoke) on its public website and provides DR data to EUMETCast users. The IPOPP-based software packages are available through DRL to a broad DR user community worldwide.

Seismic Monitoring during Crises at the NEIC in Support of the ANSS

Over the past two decades, the U.S. Geological Survey (USGS) National Earthquake Information Center (NEIC) has overcome many operational challenges. These range from minor disruptions, such as power outages, to significant operational changes, including system reconfiguration to handle unique earthquake sequences and the need to handle distributed work during a pandemic. Our ability to overcome crises is built on the development and implementation of a continuity of operations plan, well-designed infrastructure, adaptive software systems, experienced staff, and extensive collaboration. The NEIC does not operate in a vacuum but benefits from contributions of United States and international seismic networks. Similarly, the overall resilience of earthquake monitoring in the United States and around the globe benefits from the NEIC’s role as the national center for the Advanced National Seismic System (ANSS). Here, we highlight significant adaptations the NEIC has made in the face of crises. We discuss the COVID-19 pandemic, which represents the most significant operational crisis to impact the NEIC. The NEIC has maintained continuous operations during the ongoing COVID-19 pandemic by shifting from a fully onsite operations center to a distributed hybrid of onsite and telework staffing. We then discuss cases in which the NEIC has supported regional monitoring in the face of significant crises. In 2018, the NEIC assisted the Hawaiian Volcano Observatory with the Kīlauea volcano eruption by responding to large events, implementing contingency monitoring procedures, and calculating moment magnitudes for the low-frequency caldera collapses. Impacts of a crisis extend beyond the immediate response and often require a significant postevent assessment and a rebuilding phase. After the 2017 Hurricane Maria, the NEIC, the USGS National Strong-Motion Program, and the USGS Albuquerque Seismological Laboratory worked with the Puerto Rico Seismic Network and the Puerto Rico Strong-Motion program to assess, plan, and implement upgrades at sites that experienced storm damage.

Remote Triggering of Icequakes at Mt. Erebus, Antarctica by Large Teleseismic Earthquakes

Recent studies have shown that the Antarctic cryosphere is sensitive to external disturbances such as tidal stresses or dynamic stresses from remote large earthquakes. In this study, we systematically examine evidence of remotely triggered microseismicity around Mount (Mt.) Erebus, an active high elevation stratovolcano located on Ross Island, Antarctica. We detect microearthquakes recorded by multiple stations from the Mt. Erebus Volcano Observatory Seismic Network one day before and after 43 large teleseismic earthquakes, and find that seven large earthquakes (including the 2010 Mw 8.8 Maule, Chile, and 2012 Mw 8.6 Indian Ocean events) triggered local seismicity on the volcano, with most triggered events occurring during the passage of the shorter-period Rayleigh waves. In addition, their waveforms and locations for the triggered events are different when comparing with seismic events arising from the persistent small-scale eruptions, but similar to other detected events before and after the mainshocks. Based on the waveform characteristics and their locations, we infer that these triggered events are likely shallow icequakes triggered by dilatational stress perturbations from teleseismic surface waves. We show that teleseismic earthquakes with higher peak dynamic stress changes are more capable of triggering icequakes at Mt. Erebus. We also find that the icequakes in this study are more likely to be triggered during the austral summer months. Our study motivates the continued monitoring of Mount Erebus with dense seismic instrumentation to better understand interactions between dynamic seismic triggering, crospheric processes, and volcanic activity.

Array-Based Convolutional Neural Networks for Automatic Detection and 4D Localization of Earthquakes in Hawai‘i

The growing amount of seismic data necessitates efficient and effective methods to monitor earthquakes. Current methods are computationally expensive, ineffective under noisy environments, or labor intensive. We leverage advances in machine learning to propose an improved solution, ArrayConvNet—a convolutional neural network that uses continuous array data from a seismic network to seamlessly detect and localize events, without the intermediate steps of phase detection, association, travel-time calculation, and inversion. When testing this methodology with events at Hawai‘i, we achieve 99.4% accuracy and predict hypocenter locations within a few kilometers of the U.S. Geological Survey catalog. We demonstrate that training with relocated earthquakes reduces localization errors significantly. We outline several ways to improve the model, including enhanced data augmentation and use of relocated offshore earthquakes recorded by ocean-bottom seismometers. Application to continuous records shows that our algorithm detects 690% as many earthquakes as the published catalog, and 125% as many events than the Hawaiian Volcano Observatory internal catalog. Because of the enhanced detection sensitivity, localization granularity, and minimal computation costs, our solution is valuable, particularly for real-time earthquake monitoring.

Towards operational use of satellite SO2 measurements in a volcano observatory

<p>Along with monitoring of seismic activity and ground deformation, the measurement of volcanic gas emissions and composition plays a key role in the surveillance of active volcanoes and the mitigation of volcanic hazards. Volcanic gas emissions also potentially impact the environment, human health and climate, providing further motivation for study. Currently, volcano observatories typically employ ground-based or airborne techniques to monitor volcanic gas emissions, mainly sulfur dioxide (SO<sub>2</sub>) fluxes and its ratios over other species (e.g., CO<sub>2</sub>, H<sub>2</sub>S). However, in recent years there have been significant breakthroughs in satellite observations of passive volcanic SO<sub>2</sub> emissions, including high-resolution ultraviolet (UV) measurements from the Tropospheric Monitoring Instrument (TROPOMI) on the Sentinel-5 Precursor (S5P) satellite, and the development of long-term records of volcanic SO<sub>2</sub> degassing from the Ozone Monitoring Instrument (OMI) on NASA’s Aura satellite. Satellite measurements offer some advantages over traditional gas monitoring techniques, e.g., synoptic coverage of large regions, relative immunity to variations in wind direction, and ability to map the spatial extent and dispersion of volcanic SO<sub>2</sub> plumes with applications for health hazard mitigation. Although these satellite datasets are potentially valuable for active volcano monitoring and as a supplement to other gas monitoring techniques, significant barriers remain to their use at many volcano observatories, particularly in low-income countries. Notably, the increasing volume of satellite datasets (NASA’s database is bigger than 3 petabytes) and the demands of data processing represent challenges to their operational use at observatories with limited internet connectivity or computational capacity. Here, we present an ongoing effort to develop open-source Python software to access and process SO<sub>2</sub> data directly through NASA’s Earthdata portal Application Processing Interface (API), in order to streamline the satellite SO<sub>2</sub> data processing workflow for a volcano observatory. By allowing server-side satellite data subsetting around the volcano of interest, this API greatly reduces the processing burden and only requires an internet connection to the NASA server hosting the required datasets (including S5P/TROPOMI, Aura/OMI and many others). We present some examples of software output and potential applications. Our current goal is to deploy and test the software for operational use in a volcano observatory.  </p>