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1.
Nature ; 614(7948): 393, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36737548
2.
mBio ; 14(1): e0331322, 2023 02 28.
Article in English | MEDLINE | ID: mdl-36629429

ABSTRACT

The island of Hunga Tonga Hunga Ha'apai (HTHH) in the Kingdom of Tonga was formed by Surtseyan eruptions and persisted for 7 years before being obliterated by a massive volcanic eruption on 15 January 2022. Before it was destroyed, HTHH was an unparalleled natural laboratory to study primary succession on a newly formed landmass. We characterized the microbial communities found on the surface sediments of HTHH using a combination of quantitative PCR, marker gene sequencing, and shotgun metagenomic analyses. Contrary to expectations, photosynthetic cyanobacteria were not detected in these sediments, even though they are typically dominant in the earliest stages of primary succession in other terrestrial environments. Instead, our results suggest that the early sediment communities were composed of a diverse array of bacterial taxa, including trace gas oxidizers, anoxygenic photosynthesizers, and chemolithotrophs capable of metabolizing inorganic sulfur, with these bacteria likely sourced from nearby active geothermal environments. While the destruction of HTHH makes it impossible to revisit the site to conduct in situ metabolic measurements or observe how the microbial communities might have continued to change over time, our results do suggest that the early microbial colonizers have unique origins and metabolic capabilities. IMPORTANCE The volcanic island of Hunga Tonga Hunga Ha'apai in the Kingdom of Tonga represents a very rare example of new island formation and thus a unique opportunity to study how organisms colonize a new landmass. We found that the island was colonized by diverse microbial communities shortly after its formation in 2015, with these microbes likely originating from nearby geothermal environments. Primary succession in this system was distinct from that typically observed in other terrestrial environments, with the early microbial colonizers relying on unique metabolic strategies to survive on the surface of this newly formed island, including the capacity to generate energy via sulfur and trace gas metabolism.


Subject(s)
Cyanobacteria , Tonga , Cyanobacteria/metabolism , Volcanic Eruptions/analysis , Sulfur/metabolism
3.
Nature ; 614(7946): 11, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36658360
4.
Ecology ; 104(3): e3950, 2023 03.
Article in English | MEDLINE | ID: mdl-36484720

ABSTRACT

The 1980 volcanic eruption of Mount St. Helens had profound impacts on the geology, hydrology, and ecology of its surrounding landscapes. Consequently, the event provided a unique opportunity to study ecological change over time in relation to abiotic factors. To better assess the role localized environmental conditions play in these larger processes, we have monitored micrometeorological conditions across six disturbance zones on Mount St. Helens created by the eruption. We deployed 823 environmental sensors at 191 sites from 1997 to 2022 to measure the temperature and relative humidity of aquatic (temperature only) and terrestrial habitats in these areas, collecting over 4.2 million measurements in total. Measurements were typically recorded every 30 min from late spring through mid-fall, with the exception being Spirit Lake, where temperatures have been measured hourly on a year-round basis since 2002. These data have been used to address two broad research questions: (1) how small-scale environmental conditions influence patterns of survivorship and/or establishment on Mount St. Helens post-eruption for a range of organisms, including plants, small mammals, birds, amphibians, arthropods, fish, and other aquatic biota, and (2) to quantify and compare these environmental conditions across different disturbance zones, which vary in disturbance type, intensity, and history of post-eruption secondary disturbances. Due to the repeatability of these measurements over many years, these data lend themselves to exploring the relationship between forest succession and microclimate, especially with respect to forest-dwelling organisms whose spread and demography are sensitive to temperature and relative humidity. In addition, this dataset could be used to investigate additional questions related to early succession, disturbance ecology, climate change, or volcano ecology. This dataset is available in the R data package MSHMicroMetR, which also includes an R Shiny data visualization and exploration tool. There is no copyright on the data; please cite this data paper Ecology when using these data.


Subject(s)
Ecosystem , Forests , Animals , Volcanic Eruptions , Amphibians , Temperature , Mammals
5.
Environ Res ; 216(Pt 2): 114486, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36206927

ABSTRACT

INTRODUCTION: Volcanic eruptions emit gases and particulate matter into the atmosphere which, if inhaled, can have an impact on health. The eruption of the volcano situated in the Cumbre Vieja Nature Reserve (La Palma, Canary Islands, Spain) affords a unique opportunity to study the effect of such a phenomenon on health. The aim of the proposed study is to assess the short-, medium- and long-term respiratory health effects of exposure to volcanic emissions from the eruption in three different population groups. METHODS: We propose to undertake a multidesign study: an ambispective cohort study to analyze the effect of the eruption on the general population, the highly exposed population, and the childhood population; and a pre-post quasi-experimental study on subjects with previously diagnosed respiratory diseases. The information will be collected using a personal interview, biologic specimens, air pollution data, data from medical records, respiratory tests and imaging tests. The study has an envisaged follow-up of five years, to run from the date of initial recruitment, with annual data-collection. This study has been approved by the Santa Cruz de Tenerife Provincial Research Ethics Committee (Canary Island Health Service) on March 10, 2022. CONCLUSIONS: This study will make it possible to advance our knowledge of the effect a volcano eruption has on population health, both short- and long-term, and to assess the potential respiratory injury attributable to volcanic eruptions. It may serve as a model for future studies of new volcanic eruptions in the coming years.


Subject(s)
Air Pollution , Volcanic Eruptions , Humans , Child , Volcanic Eruptions/adverse effects , Spain/epidemiology , Cohort Studies , Particulate Matter/analysis , Air Pollution/adverse effects
7.
Sensors (Basel) ; 22(24)2022 Dec 08.
Article in English | MEDLINE | ID: mdl-36559985

ABSTRACT

With the support of public authorities and research institutions, volcanic ash fallout and its impact on the safety of people, infrastructure and services are addressed with the aim of defining protocols and instruments for the reliable and effective handling of related emergencies. Most of the solutions proposed in the literature on ash fallout monitoring suffer from high cost and are demanding in terms of installation and maintenance. The approach suggested in this work is based on the use of a low-cost vision embedded system and a dedicated algorithm which automatically processes acquired frames of ground-deposited volcanic ash in order to estimate the main geometric properties of each particle identified in the work area. A complete characterization of the system is presented, along with a robustness analysis of particle shapes, their orientation and their position in the inspected frame. An accuracy of ±40.2 µm (with a 3σ limit) and a resolution of 32.9 µm (in the worst case), over a framed area of 130 mm by 100 mm, were estimated; these values would fulfill the objectives of the application.


Subject(s)
Volcanic Eruptions , Humans
8.
Sci Rep ; 12(1): 22485, 2022 12 28.
Article in English | MEDLINE | ID: mdl-36577789

ABSTRACT

Zircon double dating (ZDD) of comendite lava reveals an eruption age of 7.0 ± 0.9 ka for the Qixiangzhan eruption (QXZ), Changbaishan-Tianchi volcano, China/DPRK. This age is supported by new 40Ar/39Ar sanidine experiments and a previous age control from charcoal at the base of the QXZ. The revised age supports correlations with distal ash in Eastern China and Central Japan and establishes a significant (estimated at Volcanic Explosivity Index 5+) eruption that may provide a useful Holocene stratigraphic marker in East Asia. The new age indicates that the QXZ lava does not record a ca. 17 ka Hilina Pali/Tianchi geomagnetic field excursion but rather a heretofore unrecognized younger Holocene excursion at ca. 7-8 ka. Comparison between U-Th zircon crystallization and ZDD as well as 40Ar/39Ar sanidine ages indicates a protracted period of accumulation of the QXZ magma that extends from ca. 18 ka to the eruption age. This connotes an eruption that mixed remobilized early formed crystals (antecrysts) from prior stages of magma accumulation with crystals formed near the time of eruption. Based on these results, a recurrence rate of ca. 7-8 ka for the Changbaishan-Tianchi magma system is found over the last two major eruption cycles.


Subject(s)
Silicates , Volcanic Eruptions , Silicates/chemistry , China
9.
Nature ; 611(7934): 35-36, 2022 11.
Article in English | MEDLINE | ID: mdl-36323806
10.
Nature ; 611(7934): 74-80, 2022 11.
Article in English | MEDLINE | ID: mdl-36323809

ABSTRACT

North Pacific deoxygenation events during the last deglaciation were sustained over millennia by high export productivity, but the triggering mechanisms and their links to deglacial warming remain uncertain1-3. Here we find that initial deoxygenation in the North Pacific immediately after the Cordilleran ice sheet (CIS) retreat4 was associated with increased volcanic ash in seafloor sediments. Timing of volcanic inputs relative to CIS retreat suggests that regional explosive volcanism was initiated by ice unloading5,6. We posit that iron fertilization by volcanic ash7-9 during CIS retreat fuelled ocean productivity in this otherwise iron-limited region, and tipped the marine system towards sustained deoxygenation. We also identify older deoxygenation events linked to CIS retreat over the past approximately 50,000 years (ref. 4). Our findings suggest that the apparent coupling between the atmosphere, ocean, cryosphere and solid-Earth systems occurs on relatively short timescales and can act as an important driver for ocean biogeochemical change.


Subject(s)
Ice Cover , Oceans and Seas , Oxygen , Seawater , Volcanic Eruptions , Atmosphere/chemistry , Iron/analysis , Iron/metabolism , Oxygen/metabolism , Seawater/chemistry , Pacific Ocean
11.
Sci Rep ; 12(1): 19344, 2022 Nov 11.
Article in English | MEDLINE | ID: mdl-36369519

ABSTRACT

Volcanic activity provides a unique opportunity to study the ecological responses of organisms to catastrophic environmental destruction as an essential driver of biodiversity change on islands. However, despite this great scientific interest, no study of the biodiversity at an erupting volcano has yet been undertaken. On La Palma (Canary archipelago), we quantified the main species affected and their fate during the 85-day eruption (September-December 2021). Our main objective consisted of monitoring the biodiversity subjected to critical stress during this volcanic eruption. We found that all biodiversity within a 2.5 km radius was severely affected after the first two weeks. It is challenging to assess whether volcanism can drive evolutionary traits of insular organisms. Examples are the adaptation of an endemic conifer to high temperatures, selection of functional plant types-secondary woodiness-, effects of the disappearance of invertebrates and their influence in trophic nets and vertebrate trophic plasticity. However, our data suggest that such previous evolutionary changes might continue to favour their resilience during this eruption. Lastly, it is a very good opportunity to assess the extent to which these periodic volcanic catastrophes may constitute temporary windows of repeated opportunities for the evolution and speciation of oceanic island biota.


Subject(s)
Biodiversity , Volcanic Eruptions , Animals , Islands , Oceans and Seas , Invertebrates
12.
Science ; 378(6619): 554-557, 2022 11 04.
Article in English | MEDLINE | ID: mdl-36378963

ABSTRACT

Explosive volcanic eruptions can loft ash, gases, and water into the stratosphere, which affects both human activities and the climate. Using geostationary satellite images of the 15 January 2022 eruption of the Hunga Tonga-Hunga Ha'apai volcano, we find that the volcanic plume produced by this volcano reached an altitude of 57 kilometers at its highest extent. This places the plume in the lower mesosphere and provides observational evidence of a volcanic eruption injecting material through the stratosphere and directly into the mesosphere. We then discuss potential implications of this injection and suggest that the altitude reached by plumes from previous eruptions, such as the eruption of Mount Pinatubo in 1991, may have been underestimated because of a lack of observational data.


Subject(s)
Disasters , Volcanic Eruptions , Humans , Tonga , Climate , Water
13.
Sensors (Basel) ; 22(22)2022 Nov 13.
Article in English | MEDLINE | ID: mdl-36433367

ABSTRACT

Volcanic eruptions pose a great threat to humans. In this context, volcanic hazard and risk assessment constitute crucial issues with respect to mitigating the effects of volcanic activity and ensuring the health and safety of inhabitants. Lava flows directly affect communities living near active volcanoes. Nowadays, remote sensing advances make it possible to effectively monitor eruptive activity, providing immediate and accurate information concerning lava evolution. The current research focuses on the mapping of the surface deformation and the analysis of lava flow evolution occurred on the island of La Palma, during the recent (2021) eruptive phase of the volcano. Sentinel-1 data covering the island were collected throughout the entire eruptive period, i.e., September 2021 until January 2022. The processing was based on amplitude-based and phase-based detection methods, i.e., Synthetic Aperture Radar interferometry (InSAR) and offset tracking. In particular, ground deformation occurred on the island, while Line-Of-Sight (LOS) displacements were derived from Sentinel-1 interferograms. Moreover, the evolution of lava flow velocity was estimated using Sentinel-1 imagery along with offset tracking technique. The maximum lava flow velocity was calculated to be 2 m/day. It was proved that both approaches can provide rapid and useful information in emergencies, especially in inaccessible areas. Although offset tracking seems a quite promising technique for the mapping of lava flows, it still requires improvement.


Subject(s)
Imagery, Psychotherapy , Volcanic Eruptions , Humans , Spain , Interferometry , Radar
14.
Sci Rep ; 12(1): 19557, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36380001

ABSTRACT

Deception Island is one of the most active volcanoes in Antarctica with more than twenty explosive eruptions in the past two centuries. Any future volcanic eruption(s) is a serious concern for scientists and tourists, will be detrimental to marine ecosystems and could have an impact to global oceanographic processes. Currently, it is not possible to carry-out low and high frequency volcanic gas monitoring at Deception Island because of the arduous climatic conditions and its remote location. Helium, neon and argon isotopes measured in olivine samples of the main eruptive events (pre-, syn- and post caldera) offer insights into the processes governing its volcanic history. Our results show that: (i) ascending primitive magmas outgassed volatiles with a MORB-like helium isotopic signature (3He/4He ratio); and (ii) variations in the He isotope ratio, as well as intensive degassing evidenced by fractionated 4He/40Ar* values, occurred before the beginning of the main eruptive episodes. Our results show how the pre-eruptive noble gas signals of volcanic activity is an important step toward a better understanding of the magmatic dynamics and has the potential to improve eruption forecasting.


Subject(s)
Ecosystem , Helium , Antarctic Regions , Volcanic Eruptions , Isotopes/analysis , Deception
16.
Sensors (Basel) ; 22(20)2022 Oct 11.
Article in English | MEDLINE | ID: mdl-36298065

ABSTRACT

Volcanic explosive eruptions inject several different types of particles and gasses into the atmosphere, giving rise to the formation and propagation of volcanic clouds. These can pose a serious threat to the health of people living near an active volcano and cause damage to air traffic. Many efforts have been devoted to monitor and characterize volcanic clouds. Satellite infrared (IR) sensors have been shown to be well suitable for volcanic cloud monitoring tasks. Here, a machine learning (ML) approach was developed in Google Earth Engine (GEE) to detect a volcanic cloud and to classify its main components using satellite infrared images. We implemented a supervised support vector machine (SVM) algorithm to segment a combination of thermal infrared (TIR) bands acquired by the geostationary MSG-SEVIRI (Meteosat Second Generation-Spinning Enhanced Visible and Infrared Imager). This ML algorithm was applied to some of the paroxysmal explosive events that occurred at Mt. Etna between 2020 and 2022. We found that the ML approach using a combination of TIR bands from the geostationary satellite is very efficient, achieving an accuracy of 0.86, being able to properly detect, track and map automatically volcanic ash clouds in near real-time.


Subject(s)
Sodium Glutamate , Volcanic Eruptions , Humans , Atmosphere , Gases , Machine Learning
17.
Sci Rep ; 12(1): 17895, 2022 Oct 25.
Article in English | MEDLINE | ID: mdl-36284217

ABSTRACT

From the 2010s on, pattern classification has proven an effective method for flagging alerts of volcano unrest before eruptive activity at Mt. Etna, Italy. The analysis has been applied online to volcanic tremor data, and has supported the surveillance activity of the volcano that provides timely information to Civil Protection and other authorities. However, after declaring an alert, no one knows how long the volcano unrest will last and if a climactic eruptive activity will actually begin. These are critical aspects when considering the effects of a prolonged state of alert. An example of longstanding unrest is related to the Christmas Eve eruption in 2018, which was heralded by several months of almost continuous Strombolian activity. Here, we discuss the usage of thresholds to detect conditions leading to paroxysmal activity, and the challenges associated with defining such thresholds, leveraging a dataset of 52 episodes of lava fountains occurring in 2021. We were able to identify conservative settings regarding the thresholds, allowing for an early warning of impending paroxysm in almost all cases (circa 85% for the first 4 months in 2021, and over 90% for the whole year). The chosen thresholds also proved useful to predict that a paroxysmal activity was about to end. Such information provides reliable numbers for volcanologists for their assessments, based on visual information, which may not be available in bad weather or cloudy conditions.


Subject(s)
Tremor , Volcanic Eruptions , Humans , Italy , Physical Phenomena
18.
Proc Natl Acad Sci U S A ; 119(38): e2120441119, 2022 09 20.
Article in English | MEDLINE | ID: mdl-36095185

ABSTRACT

Refinements of the geological timescale driven by the increasing precision and accuracy of radiometric dating have revealed an apparent correlation between large igneous provinces (LIPs) and intervals of Phanerozoic faunal turnover that has been much discussed at a qualitative level. However, the extent to which such correlations are likely to occur by chance has yet to be quantitatively tested, and other kill mechanisms have been suggested for many mass extinctions. Here, we show that the degree of temporal correlation between continental LIPs and faunal turnover in the Phanerozoic is unlikely to occur by chance, suggesting a causal relationship linking extinctions and continental flood basalts. The relationship is stronger for LIPs with higher estimated eruptive rates and for stage boundaries with higher extinction magnitudes. This suggests LIP magma degassing as a primary kill mechanism for mass extinctions and other intervals of faunal turnover, which may be related to [Formula: see text], Cl, and F release. Our results suggest continental LIPs as a major, direct driver of extinctions throughout the Phanerozoic.


Subject(s)
Extinction, Biological , Silicates , Volcanic Eruptions
19.
Sci Total Environ ; 853: 158389, 2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36055506

ABSTRACT

Andean volcanic rocks typically have low to moderate arsenic (As) concentrations. However, elevated levels of As in groundwaters of southern South America have been reported as a consequence of weathering of volcanic glass. This study discusses the abundance, speciation and dispersion of As species in fresh volcanic ash from highly explosive (Volcanic Explosivity Index: 4-5) Patagonian eruptions, as well as the potential of As release to aqueous reservoirs. Synchrotron-based X-ray absorption and micro-focused X-ray photoelectron spectroscopies were used to evaluate As solid speciation. Batch experiments at different pH conditions were performed with the aim of understanding the controls on As release to aqueous reservoirs. Bulk chemical and mineralogical characterizations were performed by inductively coupled plasma optical emission spectroscopy, X-ray diffraction and scanning electron microscopy/energy dispersive spectroscopy. Finally, to understand how As-bearing phases are spatially distributed after eruptions, simulations of volcanic ash emission, transport and deposition were performed. Results indicate that the concentration, speciation, and mobility of As in fresh Patagonian volcanic ash depend on the silica content of source magmas. Although the main As host in volcanic ash is Al-silicate glass, this phase is stable at neutral pH characteristic of most aqueous reservoirs. Higher contributions of As to water are associated with the more mobile As species that concentrate onto the surface of Al-silicate glass. Atmospheric dispersion simulations revealed that primary fallout of As-bearing ash has affected large areas in Patagonia, but also reached the Chaco-Pampean plain, where the presence of As-rich groundwater has been widely documented.


Subject(s)
Arsenic , Explosive Agents , Volcanic Eruptions , Water , Silicates , Silicon Dioxide
20.
Sci Total Environ ; 849: 157827, 2022 Nov 25.
Article in English | MEDLINE | ID: mdl-35944626

ABSTRACT

The eruption of the Cumbre Vieja volcano on the island of La Palma (Canary Islands, Spain) began on September 19, 2021 and ended on December 13, 2021. It lasted continuously for 85 days with short periods of calm when lava did not exit the cone of the volcano. Vast amounts of volcanic material, including ash and gases, were emitted into the environment. This research focuses on these emissions. The main objective is to use available open-source data to examine the impact on regional and local air quality. Data from the following sources were used: 1) Copernicus Atmosphere Monitoring Service (CAMS) data was used to track the transfer of volcanic SO2 in the troposphere in early October over long distances from the source of the eruption, including Western and Eastern Europe, across the Atlantic Ocean and the Caribbean; 2) Data from ground monitoring stations measured the concentrations of SO2 and PM10 near the source; 3) AErosol RObotic NETwork (AERONET) data from the La Palma station that showed high Aerosol Optical Depth (AOD) values (over 0.4) during the active phase of emissions on September 24 and 28, as well as on October 3; 4) Ångström Exponent (AE) values indicated the presence of particles of different sizes. On September 24, high AE values (>1.5), showed the presence of fine-mode fraction scattering aerosols such as sulfates; 5) Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data additionally confirmed the presence of sulfate and dust aerosols in the atmosphere over the region. However, the influence of Saharan dust on the atmosphere of the entire region could not be excluded. This research helps forecast air pollution resulting from large-scale volcanic eruptions and associated health risks to humans.


Subject(s)
Air Pollutants , Air Pollution , Aerosols/analysis , Air Pollutants/analysis , Air Pollution/analysis , Dust/analysis , Environmental Monitoring/methods , Gases , Humans , Spain , Sulfates , Volcanic Eruptions
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