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Tamar Elias

Publications and source records attributed to Tamar Elias.

At least 19 recordsLinked to original sources
USGS2024

Volcanic gas monitoring

Introduction As magma rises through the crust, decreasing pressure conditions allow volatiles to exsolve from the magma. These volatiles then migrate upward through the crust, where they can be stored at shallower levels or escape to the atmosphere. Rising magma also heats rock masses beneath volcanic centers, causing water in shallow aquifers and hydrothermal systems to boil and release additional gases and steam (see chapter F , this volume; Ingebritsen and Hurwitz, 2024). The chemistry and quantity of gases that reach the surface during periods of quiescence or volcanic unrest can reveal that gas-rich magma is ascending, crystallizing, or alternatively stalling, with important implications for volcanic hazard (for example, Sutton and others, 1992; Aiuppa and others, 2007, 2021; Werner and others, 2009, 2011, 2012; Moretti and others, 2013; de Moor and others, 2016; Lewicki and others, 2019; Edmonds and others, 2022; Kern and others, 2022; Kunrat and others, 2022). Most volcanoes in Alaska and the western United States are characterized by weak degassing, with one or more low-temperature fumaroles (typically near the local boiling temperature of water) and connect to a deeper and sometimes extensive hydrothermal system (for example, McGee and others, 2001; Symonds and others, 2003a, b). Hydrothermal systems will affect the chemistry of rising gases exsolved from deeper magma (Symonds and others, 2001), including sulfur dioxide (SO 2 ), hydrogen chloride (HCl), and water vapor (for example, Doukas and Gerlach, 1995; Gerlach and others, 1998, 2008; Symonds and others, 2001; Werner and others, 2013). As an example, depending on factors such as temperature, pressure, and oxidation state, rising SO 2 will react with groundwater to form hydrogen sulfide (H 2 S) gas, dissolved sulfate (SO 4 2− ), or elemental sulfur (Christenson, 2000; Symonds and others, 2001; Werner and others, 2008). The reaction and dissolution of SO 2 into shallow groundwater is commonly referred to as scrubbing, and can reduce the likelihood that ascending, degassing magma can be detected. Carbon dioxide, however, in addition to exsolving from magma early in the ascent process, is not easily removed by hydrothermal fluids (Lowenstern, 2001). As scrubbing and other processes take place, the SO 2 /H 2 S, CO 2 /SO 2 , and CO 2 /H 2 S ratios may change. High rates of SO 2 emission indicate that magma has moved to relatively shallow levels in the volcano and that the system has heated up enough to establish dry pathways from depth to the surface. Monitoring multiple gas species and the total output of those species is thereby useful for volcano monitoring during both periods of quiescence, to establish background degassing conditions, and during unrest, when gas geochemistry and emission rates can provide information on changing conditions, such as magma ascent. To provide context for multidisciplinary volcano forecasts, we focus on the following two key required capabilities: (1) characterizing baseline geochemistry and gas discharge from volcanoes and volcanic regions and (2) monitoring changes in gas geochemistry and discharge to inform forecasts of volcanic eruptions and their effects. Sufficient baseline data must be collected to identify and interpret anomalous degassing associated with volcanic unrest (for example, Sorey and others, 1998; Rouwet and others, 2014). Differences in volcano type, baseline degassing rates, local hydrology, and geography (for example, high versus low latitude) will result in a different baseline for each volcano. Volcanoes of any threat level that exhibit one or more degassing phenomena would ideally be monitored by techniques needed to establish baseline degassing data, with the sampling frequency of baseline data dictated by the threat level (table E1). Additional monitoring techniques become necessary during periods of unrest. In general, three of the most important techniques for gas monitoring are (1) direct sampling of fumarole, spring, and soil gases for laboratory geochemical measurements, (2) measurements of the chemical composition of the volcanic plume and emission rates of major gas species (for example, H 2 O, CO 2 , SO 2 , and H 2 S) by satellite, airborne, or ground-based techniques, and (3) measurements of diffuse emissions of CO 2 and other gases through soils. Various methods and instruments may be useful both for baseline studies and during unrest.

Scientific Investigations Report↗
USGS2023

Hawaiian volcanic ash, an airborne fomite for nontuberculous mycobacteria

Nontuberculous mycobacteria (NTM) are environmentally acquired opportunistic pathogens that can cause chronic lung disease. Within the U.S., Hawai'i shows the highest prevalence rates of NTM lung infections. Here, we investigated a potential role for active volcanism at the Kīlauea Volcano located on Hawai'i Island in promoting NTM growth and diversity. We recovered NTM that are known to cause lung disease from plumbing biofilms and soils collected from the Kīlauea environment. We also discovered viable Mycobacterium avium, Mycobacterium abscessus , and Mycobacterium intracellulare subsp. chimaera on volcanic ash collected during the 2018 Kīlauea eruption. Analysis of soil samples showed that NTM prevalence is positively associated with bulk content of phosphorus, sulfur, and total organic carbon. In growth assays, we showed that phosphorus utilization is essential for proliferation of Kīlauea-derived NTM, and demonstrate that NTM cultured with volcanic ash adhere to ash surfaces and remain viable. Ambient dust collected on O'ahu concurrent with the 2018 eruption contained abundant fresh volcanic glass, suggestive of inter-island ash transport. Phylogenomic analyses using whole genome sequencing revealed that Kīlauea-derived NTM are genetically similar to respiratory isolates identified on other Hawaiian Islands. Consequently, we posit that volcanic eruptions could redistribute environmental microorganisms over large scales. While additional studies are needed to confirm a direct role of ash in NTM dispersal, our results suggest that volcanic particulates harbor and can redistribute NTM and should therefore be studied as a fomite for these burgeoning, environmentally acquired respiratory infections.

Hawaii↗
USGS2023

VogCast: A framework for modeling volcanic air pollution and its application to the 2022 eruption of Mauna Loa Volcano, Hawai'i

Volcanic activity and the associated gas emissions into the atmosphere often result in adverse air quality conditions and present a hazard to human health and the environment. Building on a decade-long effort to provide operational surface sulfur dioxide and sulfate aerosol forecasts for the State of Hawai'i, we present an air quality modeling framework called VogCast. VogCast is designed to simplify ensemble air quality prediction on a regional scale by linking together multiple state-of-the-art models of meteorology, emissions, and dispersion. The framework is open-source and introduces a new dynamic plume-rise algorithm for distributing pollutants vertically. Using radar and satellite data, we demonstrate that VogCast reasonably captured the mean injection height, the location, and the general envelope of the vog plume during Mauna Loa's 2022 eruption. The results suggest that during the 12-day eruption period model performance varied between days with trade and non-trade wind conditions. Our findings also highlight the importance of sulfur dioxide emission rate and vent parameter inputs for improving forecast accuracy. The broad goal of this work is to better our understanding of vog dispersion and improve air quality prediction for impacted communities.

Hawaii↗
USGS2023

Out of the frying pan and into the fire: Effects of volcanic heat and other stressors on the conservation of a critically endangered plant in Hawaiʻi

Loss of local biodiversity resulting from abrupt environmental change is a significant environmental problem throughout the world. Extinctions of plants are particularly important yet are often overlooked. Drawing from a case in Hawai‘i, a global hotspot for plant and other extinctions, we demonstrate an effort to better understand and determine priorities for the management of an endangered plant (‘Ihi makole or Portulaca sclerocarpa ) in the face of rapid and extreme environmental change. Volcanic heat emissions and biological invasions have anecdotally been suggested as possible threats to the species. We integrated P. sclerocarpa outplanting with efforts to collect geological and ecological data to gauge the role of elevated soil temperatures and invasive grasses in driving P. sclerocarpa mortality and population decline. We measured soil temperature, soil depth, surrounding cover and P. sclerocarpa survivorship over three decades. The abundance of wild P. sclerocarpa decreased by 99.7% from the 1990s to 2021. Only 51% of outplantings persisted through 3–4 years. Binomial regression and structural equation modelling revealed that, among the variables we analysed, high soil temperatures were most strongly associated with population decline. Finding the niche where soil temperatures are low enough to allow P. sclerocarpa survival but high enough to limit other agents of P. sclerocarpa mortality may be necessary to increase population growth of this species.

Hawaii↗
USGS2023

Perceptions of volcanic air pollution and exposure reduction practices on the Island of Hawai‘i: Working towards socially relevant risk communication

Kīlauea volcano, on the Island of Hawai‘i, is one of the most active volcanoes in the world. Over the past four decades it has released large amounts of volcanic gases and aerosols which form volcanic air pollution known as ‘vog’. Communities downwind of Kīlauea have been chronically or episodically exposed to this potentially harmful air pollution and have raised concerns about the hazards of vog exposure. Public health and civil protection agencies have offered a range of advice, information, and mitigation strategies for living with vog. In this mixed-methods social study, we investigate the translation of official advice into practice in Island of Hawai‘i communities and assess how risk communication could be improved by considering public input, preferences, and community relevance. Given the paucity of information on the long-term effects of chronic vog exposure, assessing the effectiveness of public health and risk communication is vital.

Hawaii↗
USGS2021

Volcanic air pollution and human health: Recent advances and future directions

Volcanic air pollution from both explosive and effusive activity can affect large populations as far as thousands of kilometers away from the source, for days to decades or even centuries. Here, we summarize key advances and prospects in the assessment of health hazards, effects, risk, and management. Recent advances include standardized ash assessment methods to characterize the multiple physicochemical characteristics that might influence toxicity; the rise of community-based air quality monitoring networks using low-cost gas and particulate sensors; the development of forecasting methods for ground-level concentrations and associated public advisories; the development of risk and impact assessment methods to explore health consequences of future eruptions; and the development of evidence-based, locally specific measures for health protection. However, it remains problematic that the health effects of many major and sometimes long-duration eruptions near large populations have gone completely unmonitored. Similarly, effects of prolonged degassing on exposed populations have received very little attention relative to explosive eruptions. Furthermore, very few studies have longitudinally followed populations chronically exposed to volcanic emissions; thus, knowledge gaps remain about whether chronic exposures can trigger development of potentially fatal diseases. Instigating such studies will be facilitated by continued co-development of standardized protocols, supporting local study teams and procuring equipment, funding, and ethical permissions. Relationship building between visiting researchers and host country academic, observatory, and agency partners is vital and can, in turn, support the effective communication of health impacts of volcanic air pollution to populations, health practitioners, and emergency managers.

Bulletin of Volcanology↗
USGS2021

The petrologic and degassing behavior of sulfur and other magmatic volatiles from the 2018 eruption of Kīlauea, Hawaiʻi: Melt concentrations, magma storage depths, and magma recycling

Kīlauea Volcano’s 2018 lower East Rift Zone (LERZ) eruption produced exceptionally high lava effusion rates and record-setting SO 2 emissions. The eruption involved a diverse range of magmas, including primitive basalts sourced from Kīlauea’s summit reservoirs. We analyzed LERZ matrix glasses, melt inclusions, and host minerals to identify melt volatile contents and magma storage depths. The LERZ glasses and melt inclusions span nearly the entire compositional range previously recognized at Kīlauea. Melt inclusions in Fo 86-89 olivine from the main eruptive vent (fissure 8) underwent 70–170 °C cooling during transport in LERZ carrier melts, causing extensive post-entrapment crystallization and sulfide precipitation. Many of these melt inclusions have low sulfur (400–900 ppm) even after correction for sulfide formation. CO 2 and H 2 O vapor saturation pressures indicate shallow melt inclusion trapping depths (1–5 km), consistent with formation within Kīlauea’s Halemaʻumaʻu and South Caldera reservoirs. Many of these inclusions also have degassed δ 34 S values (− 1.5 to − 0.5‰). Collectively, these results indicate that some primitive melts experienced near-surface degassing before being trapped into melt inclusions. We propose that decades-to-centuries of repeated lava lake activity and lava drain-back during eruptions (e.g., 1959 Kīlauea Iki) recycled substantial volumes of degassed magma into Kīlauea’s shallow reservoir system. Degassing and magma recycling from the 2008–2018 Halemaʻumaʻu lava lake likely reduced the volatile contents of LERZ fissure 8 magmas, resulting in lower fountain heights compared to many prior Kīlauea eruptions. The eruption’s extreme SO 2 emissions were due to high lava effusion rates rather than particularly volatile-rich melts.

Hawaii↗
USGS2021

Volatile metal emissions from volcanic degassing and lava–seawater interactions at Kīlauea Volcano, Hawai’i

Volcanoes represent one of the largest natural sources of metals to the Earth’s surface. Emissions of these metals can have important impacts on the biosphere as pollutants or nutrients. Here we use ground- and drone-based direct measurements to compare the gas and particulate chemistry of the magmatic and lava–seawater interaction (laze) plumes from the 2018 eruption of Kīlauea, Hawai’i. We find that the magmatic plume contains abundant volatile metals and metalloids whereas the laze plume is further enriched in copper and seawater components, like chlorine, with volatile metals also elevated above seawater concentrations. Speciation modelling of magmatic gas mixtures highlights the importance of the S 2− ligand in highly volatile metal/metalloid degassing at the magmatic vent. In contrast, volatile metal enrichments in the laze plume can be explained by affinity for chloride complexation during late-stage degassing of distal lavas, which is potentially facilitated by the HCl gas formed as seawater boils.

Hawaii↗
USGS2021

Rapid metal pollutant deposition from the volcanic plume of Kīlauea, Hawai’i

Long-lived basaltic volcanic eruptions are a globally important source of environmentally reactive, volatile metal pollutant elements such as selenium, cadmium and lead. The 2018 eruption of Kīlauea, Hawai’i produced exceptionally high discharge of metal pollutants, and was an unprecedented opportunity to track them from vent to deposition. Here we show, through geochemical sampling of the plume that volatile metal pollutants were depleted in the plume up to 100 times faster than refractory species, such as magnesium and iron. We propose that this rapid wet deposition of complexes containing reactive and potentially toxic volatile metal pollutants may disproportionately impact localised areas close to the vent. We infer that the relationship between volatility and solubility is an important control on the atmospheric behaviour of elements. We suggest that assessment of hazards from volcanic emissions should account for heterogeneous plume depletion of metal pollutants.

Hawaii↗
USGS2020

The cascading origin of the 2018 Kīlauea eruption and implications for future forecasting

The 2018 summit and flank eruption of Kīlauea Volcano was one of the largest volcanic events in Hawaiʻi in 200 years. Data suggest that a backup in the magma plumbing system at the long-lived Puʻu ʻŌʻō eruption site caused widespread pressurization in the volcano, driving magma into the lower flank. The eruption evolved, and its impact expanded, as a sequence of cascading events, allowing relatively minor changes at Puʻu ʻŌʻō to cause major destruction and historic changes across the volcano. Eruption forecasting is inherently challenging in cascading scenarios where magmatic systems may prime gradually and trigger on small events.

Hawaii↗
USGS2020

Quantifying gas emissions associated with the 2018 rift eruption of Kīlauea Volcano using ground-based DOAS measurements

Starting on 3 May 2018, a series of eruptive fissures opened in Kīlauea Volcano’s lower East Rift Zone (LERZ). Over the course of the next 3 months, intense degassing accompanied lava effusion from these fissures. Here, we report on ground-based observations of the gas emissions associated with Kīlauea’s 2018 eruption. Visual observations combined with radiative transfer modeling show that ultraviolet light could not efficiently penetrate the gas and aerosol plume in the LERZ, complicating SO 2 measurements by differential optical absorption spectroscopy (DOAS). By applying a statistical method that integrates a radiative transfer model with the DOAS retrievals, we were able to calculate sulfur dioxide (SO 2 ) emission rates along with estimates of their uncertainty. We find that sustained SO 2 emissions were highest in June and early July, when approximately 200 kt SO 2 were emitted daily. At the 68% confidence interval, we estimate that 7.1–13.6 Mt SO 2 were released from the LERZ during the entire May to September eruptive episode. Scaling our results with in situ measurements of plume composition, we calculate that 11–21 Mt H 2 O and 1.5–2.8 Mt CO 2 were also emitted. The gas and aerosol emissions caused hazardous conditions in areas proximal to the active vents, but plume dispersion modeling shows that the eruption also significantly impacted air quality hundreds of kilometers downwind. Combined with petrologic studies of the erupted lavas, our measurements indicate that 1.1–2.3 km 3 dense-rock equivalent of lava were erupted from the LERZ, which is approximately twice the concomitant collapse volume of the volcano’s summit.

Hawaii↗
USGS2020

Spatial and temporal variations in SO2 and PM2.5 levels around Kīlauea volcano, Hawai'i during 2007–2018

Among the hazards posed by volcanoes are the emissions of gases and particles that can affect air quality and damage agriculture and infrastructure. A recent intense episode of volcanic degassing associated with severe impacts on air quality accompanied the 2018 lower East Rift Zone (LERZ) eruption of Kīlauea volcano, Hawai'i. This resulted in a major increase in gas emission rates with respect to usual emission values for this volcano, along with a shift in the source of the dominant plume to a populated area on the lower flank of the volcano. This led to reduced air quality in downwind communities. We analyse open-access data from the permanent air quality monitoring networks operated by the Hawai'i Department of Health (HDOH) and National Park Service (NPS), and report on measurements of atmospheric sulfur dioxide (SO 2 ) between 2007 and 2018 and PM 2.5 (aerosol particulate matter with diameter <2.5 μm) between 2010 and 2018. Additional air quality data were collected through a community-operated network of low-cost PM 2.5 sensors during the 2018 LERZ eruption. From 2007 to 2018 the two most significant escalations in Kīlauea's volcanic emissions were: the summit eruption that began in 2008 (Kīlauea emissions averaged 5–6 kt/day SO 2 from 2008 until summit activity decreased in May 2018) and the LERZ eruption in 2018 when SO 2 emission rates reached a monthly average of 200 kt/day during June. In this paper we focus on characterizing the airborne pollutants arising from the 2018 LERZ eruption and the spatial distribution and severity of volcanic air pollution events across the Island of Hawai'i. The LERZ eruption caused the most frequent and severe exceedances of the Environmental Protection Agency (EPA) PM 2.5 air quality threshold (35 μg/m 3 as a daily average) in Hawai'i in the period 2010–2018. In Kona, for example, the maximum 24-h-mean mass concentration of PM 2.5 was recorded as 59 μg/m 3 on the twenty-ninth of May 2018, which was one of eight recorded exceedances of the EPA air quality threshold during the 2018 LERZ eruption, where there had been no exceedances in the previous 8 years as measured by the HDOH and NPS networks. SO 2 air pollution during the LERZ eruption was most severe in communities in the south and west of the island, as measured by selected HDOH and NPS stations in this study, with a maximum 24-h-mean mass concentration of 728 μg/m 3 recorded in Ocean View (100 km west of the LERZ emission source) in May 2018. Data from the low-cost sensor network correlated well with data from the HDOH PM 2.5 instruments, confirming that these low-cost sensors provide a robust means to augment reference-grade instrument networks.

Hawaii↗
USGS2020

Two ensemble approaches for forecasting sulfur dioxide concentrations from Kīlauea volcano

Kīlauea volcano, located on the island of Hawaii, is one of the most active volcanoes in the world. It was in a state of nearly continuous eruption from 1983 to 2018 with copious emissions of sulfur dioxide (SO 2 ) that affected public health, agriculture, and infrastructure over large portions of the island. Since 2010, the University of Hawaiʻi at Mānoa provides publicly available vog forecasts that began in 2010 to aid in the mitigation of volcanic smog (or “vog”) as a hazard. In September 2017, the forecast system began to produce operational ensemble forecasts. The months that preceded Kīlauea’s historic lower east rift zone eruption of 2018 provide an opportunity to evaluate the newly implemented air quality ensemble prediction system and compare it another approach to the generation of ensemble members. One of the two approaches generates perturbations in the wind field while the other perturbs the sulfur dioxide (SO 2 ) emission rate from the volcano. This comparison has implications for the limits of forecast predictability under the particularly dynamic conditions at Kīlauea volcano. We show that for ensemble forecasts of SO 2 generated under these conditions, the uncertainty associated with the SO 2 emission rate approaches that of the uncertainty in the wind field. However, the inclusion of a fluctuating SO 2 emission rate has the potential to improve the prediction of the changes in air quality downwind of the volcano with suitable postprocessing.

Hawaii↗
USGS2020

The health hazards of volcanic and geothermal gases: A guide for the public

This guide has been prepared by the International Volcanic Health Hazard Network (IVHHN) to explain the potential adverse health effects of volcanic and geothermal gas and aerosol emissions. It provides general information on how to protect yourself and your family. The information is based on a range of evidence from academics and health and regulatory agencies. Contact your local public health or emergency management agency for information tailored to your location.

Report↗
USGS2019

The 2018 rift eruption and summit collapse of Kilauea Volcano

In 2018, Kīlauea Volcano experienced its largest lower East Rift Zone (LERZ) eruption and caldera collapse in at least 200 years. After collapse of the Pu'u 'Ō'ō vent on 30 April, magma propagated downrift. Eruptive fissures opened in the LERZ on 3 May, eventually extending ~6.8 km. A 4 May earthquake (M6.9) produced ~5 m of fault slip. Lava erupted at rates exceeding 100 m3/s, eventually covering 35.5 km2. The summit magma system partially drained, producing minor explosions and near-daily collapses releasing energy equivalent to M4.7-M5.4 earthquakes. Activity declined rapidly on 4 August. Summit collapse and lava flow volume estimates are roughly equivalent--about 0.8 km3. Careful historical observation and monitoring of Kīlauea enabled successful forecasting of hazardous events.

Hawaii↗
USGS2018

Measuring SO2 emission rates at Kīlauea Volcano, Hawaii, using an array of upward-looking UV spectrometers, 2014-2017

Retrieving accurate volcanic sulfur dioxide (SO 2 ) gas emission rates is important for a variety of purposes. It is an indicator of shallow subsurface magma, and thus may signal impending eruption or unrest. SO 2 emission rates are significant for accurately assessing climate impact, and providing context for assessing environmental, agricultural, and human health effects during volcanic eruptions. The U.S. Geological Survey Hawaiian Volcano Observatory uses an array of ten fixed, upward-looking ultraviolet spectrometer systems to measure SO 2 emission rates at 10-s sample intervals from the Kīlauea summit. We present Kīlauea SO 2 emission rates from the volcano’s summit and middle East Rift Zone during 2014–2017 and discuss the major sources of error for these measurements. Due to the wide range of SO 2 emissions encountered at the summit vent, we used a variable wavelength spectral analysis range to accurately quantify both high and low SO 2 column densities. We compare measured emission rates from the fixed spectrometer array to independent road and helicopter-based traverse measurements and evaluate the magnitudes and sources of uncertainties for each method. To address the challenge of obtaining accurate plume speed measurements, we examine ground-based wind-speed, plume speed tracking via spectrometer, and SO 2 camera derived plume speeds. Our analysis shows that: (1) the summit array column densities calculated using a dual fit window, are within -6 to +22% of results obtained with a variety of other conventional and experimental retrieval methods; (2) emission rates calculated from the summit array located ∼3 km downwind provide the best, practical estimate of summit SO 2 release under normal trade wind conditions; (3) ground-based anemometer wind speeds are 22% less than plume speeds determined by cross-correlation of plume features; (4) our best estimate of average Kīlauea SO 2 release for 2014–2017 is 5100 t/d, which is comparable to the space-based OMI emissions of 5518 t/d; and (5) short-term variability of SO 2 emissions reflects Kīlauea lava lake dynamics.

Hawaii↗
USGS2018

Lava lake activity at the summit of Kīlauea Volcano in 2016

The ongoing summit eruption at Kīlauea Volcano, Hawai‘i, began in March 2008 with the formation of the Overlook crater, within Halema‘uma‘u Crater. As of late 2016, the Overlook crater contained a large, persistently active lava lake (250 × 190 meters). The accessibility of the lake allows frequent direct observations, and a robust geophysical monitoring network closely tracks subtle changes at the summit. These conditions present one of the best opportunities worldwide for understanding persistent lava lake behavior and the geophysical signals associated with open-vent basaltic eruptions. In this report, we provide a descriptive and visual summary of lava lake activity during 2016, a year consisting of continuous lava lake activity. The lake surface was composed of large black crustal plates separated by narrow incandescent spreading zones. The dominant motion of the surface was normally from north to south, but spattering produced transient disruptions to this steady motion. Spattering in the lake was common, consisting of one or more sites on the lake margin. The Overlook crater was continuously modified by the deposition of spatter (often as a thin veneer) on the crater walls, with frequent collapses of this adhered lava into the lake. Larger collapses, involving lithic material from the crater walls, triggered several small explosive events that deposited bombs and lapilli around the Halema‘uma‘u Crater rim, but these did not threaten public areas. The lava lake level varied over several tens of meters, controlled primarily by changes in summit magma reservoir pressure (in part driven by magma supply rates) and secondarily by fluctuations in spattering and gas release from the lake (commonly involving gas pistoning). The lake emitted a persistent gas plume, normally averaging 1,000–8,000 metric tons per day (t/d) of sulfur dioxide (SO 2 ), as well as a constant fallout of small juvenile and lithic particles, including Pele’s hair and tears. The gas emissions created volcanic air pollution (vog) that affected large areas of the Island of Hawai‘i. The summit eruption has been a major attraction for visitors in Hawai‘i Volcanoes National Park. During 2016, the rising lake levels allowed the lake and its spattering to be more consistently visible from public viewing areas, enhancing the visitor experience. The U.S. Geological Survey’s Hawaiian Volcano Observatory (HVO) closely monitors the summit eruption and keeps emergency managers and the public informed of activity.

Hawai'i↗