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

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Evgenia Ilyinskaya ◽  
Emily Mason ◽  
Penny E. Wieser ◽  
Lacey Holland ◽  
Emma J. Liu ◽  
...  
Keyword(s):  
Wet Deposition ◽  
Volcanic Eruptions ◽  
Volcanic Plume ◽  
Volcanic Emissions ◽  
High Discharge ◽  
Metal Pollutants ◽  
Pollutant Deposition ◽  
Cadmium And Lead ◽  
The Relationship

AbstractLong-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.

Self-limiting atmospheric lifetime of environmentally reactive elements in volcanic plumes

2020 ◽  
Author(s):  
Evgenia Ilyinskaya ◽  
Emily Mason ◽  
Penny Wieser ◽  
Lacey Holland ◽  
Emma Liu ◽  
...  
Keyword(s):  
Trace Elements ◽  
Atmospheric Dispersion ◽  
Chemical Species ◽  
Volcanic Plume ◽  
Emission Rates ◽  
Volcanic Emissions ◽  
Metal Pollutants ◽  
Volcanic Plumes ◽  
Pollutant Concentrations ◽  
Cadmium And Lead

<p>Volcanoes are a large global source of almost every element, including ~20 environmentally reactive trace elements classified as metal pollutants (e.g. selenium, cadmium and lead). Fluxes of metal pollutants from individual eruptions can be comparable to total anthropogenic emissions from large countries such as China.</p><p>The 2018 Lower East Rift Zone eruption of Kīlauea, Hawaii produced exceptionally high emission rates of major and trace chemical species compared to other basaltic eruptions over 3 months (200 kt/day of SO<sub>2</sub>; Kern et al. 2019). We tracked the volcanic plume from vent to exposed communities over 0-240 km distance using in-situ sampling and atmospheric dispersion modelling. This is the first time that trace elements in volcanic emissions (~60 species) are mapped over such distances. In 2019, we repeated the field campaign during a no-eruption period and showed that volcanic emissions had caused 3-5 orders of magnitude increase in airborne metal pollutant concentrations across the Island of Hawai’i.</p><p>We show that the volatility of the elements (the ease with which they are degassed from the magma) controls their particle-phase speciation, which in turn determines how fast they are depleted from the plume after emission. Elements with high magmatic volatilities (e.g. selenium, cadmium and lead) have up to 6 orders of magnitude higher depletion rates compared to non-volatile elements (e.g. magnesium, aluminium and rare earth metals).</p><p>Previous research and hazard mitigation efforts on volcanic emissions have focussed on sulphur and it has been assumed that other pollutants follow the same dispersion patterns. Our results show that the atmospheric fate of sulphur, and therefore the associated hazard distribution, does not represent an accurate guide to the behaviour and potential impacts of other species in volcanic emissions. Metal pollutants are predominantly volatile in volcanic plumes, and their rapid deposition (self-limited by their volatility) places disproportionate environmental burdens on the populated areas in the immediate vicinity of the active and, in turn, reduces the impacts on far-field communities.</p><p>Reference: Kern, C., T. Elias, P. Nadeau, A. H. Lerner, C. A. Werner, M. Cappos, L. E. Clor, P. J. Kelly, V. J. Realmuto, N. Theys, S. A. Carn, AGU, 2019; https://agu.confex.com/agu/fm19/meetingapp.cgi/Paper/507140.</p>

scholarly journals Probabilistic retrieval of volcanic SO<sub>2</sub> layer height and cumulative mass loading using the Cross-track Infrared Sounder (CrIS)

2020 ◽  
Author(s):  
David M. Hyman ◽  
Michael J. Pavolonis
Keyword(s):  
Real Time ◽  
Probabilistic Approach ◽  
Volcanic Eruptions ◽  
Volcanic Plume ◽  
Volcanic Emissions ◽  
So2 Emissions ◽  
Retrieval Method ◽  
Wide Range ◽  
The Cross ◽  
Cross Track

Abstract. During most volcanic eruptions and many periods of volcanic unrest, detectable quantities of sulfur dioxide (SO2) are injected into the atmosphere at a wide range of altitudes, from ground level to the lower stratosphere. Because the fine ash fraction of a volcanic plume is, at times, collocated with SO2 emissions, global tracking of volcanic SO2 is useful in tracking the hazard long after ash detection becomes dominated by noise. Typically, retrievals of SO2 loading have relied heavily on hyperspectral ultraviolet measurements. More recently, infrared sounders have provided additional loading measurements and estimates of the SO2 layer altitude, adding significant value to real-time monitoring of volcanic emissions as well as climatological analyses. These methods leverage the relative simplicity of infrared radiative transfer calculations, providing fast and accurate physics-based retrievals of loading and altitude. In this study, we detail a probabilistic enhancement of an infrared SO2 retrieval method, based on a modified trace-gas retrieval, to estimate SO2 loading and altitude probabilistically using the Cross-track Infrared Sounder (CrIS) on the Joint Polar Satellite System (JPSS) series of satellites. The methodology requires the characterization of real SO2-free spectra aggregated seasonally and spatially. The probabilistic approach replaces loading and altitude estimates with non-parametric probability density functions, fully quantifying the retrieval uncertainty. This framework adds significant value over basic loading and altitude retrieval because it can be readily incorporated into Monte Carlo forecasting of volcanic emission transport. We highlight results including successes and challenges from analysis of several recent significant eruptions including the 22 June 2019 eruption of Raikoke volcano, Kuril Islands; the mid-December 2016 eruption of Bogoslof volcano; and the 26 June 2018 eruption of Sierra Negra volcano, Galapagos Islands. This retrieval method is currently being implemented in the VOLcanic Cloud Analysis Toolkit (VOLCAT), where it will be used to generate additional cloud object properties for real-time detection, characterization, and tracking of volcanic clouds in support of aviation safety.

scholarly journals The role of tropical volcanic eruptions in exacerbating Indian droughts

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Suvarna Fadnavis ◽  
Rolf Müller ◽  
Tanusri Chakraborty ◽  
T. P. Sabin ◽  
Anton Laakso ◽  
...  
Keyword(s):  
El Niño ◽  
Climate Model ◽  
El Nino ◽  
Volcanic Eruptions ◽  
Summer Monsoon Rainfall ◽  
Indian Region ◽  
Volcanic Plume ◽  
Kelvin Wave ◽  
Central Pacific ◽  
Climate Model Simulations

AbstractThe Indian summer monsoon rainfall (ISMR) is vital for the livelihood of millions of people in the Indian region; droughts caused by monsoon failures often resulted in famines. Large volcanic eruptions have been linked with reductions in ISMR, but the responsible mechanisms remain unclear. Here, using 145-year (1871–2016) records of volcanic eruptions and ISMR, we show that ISMR deficits prevail for two years after moderate and large (VEI > 3) tropical volcanic eruptions; this is not the case for extra-tropical eruptions. Moreover, tropical volcanic eruptions strengthen El Niño and weaken La Niña conditions, further enhancing Indian droughts. Using climate-model simulations of the 2011 Nabro volcanic eruption, we show that eruption induced an El Niño like warming in the central Pacific for two consecutive years due to Kelvin wave dissipation triggered by the eruption. This El Niño like warming in the central Pacific led to a precipitation reduction in the Indian region. In addition, solar dimming caused by the volcanic plume in 2011 reduced Indian rainfall.

scholarly journals Facing metal stress by multiple strategies: morphophysiological responses of cardoon (Cynara cardunculus L.) grown in hydroponics

2021 ◽  
Author(s):  
Maria Cristina Sorrentino ◽  
Fiore Capozzi ◽  
Chiara Amitrano ◽  
Gaetano De Tommaso ◽  
Carmen Arena ◽  
...  
Keyword(s):  
Heavy Metal Contamination ◽  
Photosynthetic Pigment ◽  
Metal Stress ◽  
Cynara Cardunculus ◽  
Antioxidant Power ◽  
Metal Pollutants ◽  
Multiple Strategies ◽  
Photosynthetic Pigment Content ◽  
Cadmium And Lead ◽  
Selection Of

AbstractThe contamination of environments by heavy metals has become an urgent issue causing undesirable accumulations and severe damages to agricultural crops, especially cadmium and lead which are among the most widespread and dangerous metal pollutants worldwide. The selection of proper species is a crucial step in many plant-based restoration approaches; therefore, the aim of the present work was to check for early morphophysiological responsive traits in three cultivars of Cynara cardunculus (Sardo, Siciliano, and Spagnolo), helping to select the best performing cultivar for phytoremediation. For all three tested cultivars, our results indicate that cardoon displays some morphophysiological traits to face Cd and Pb pollution, particularly at the root morphology level, element uptake ability, and photosynthetic pigment content. Other traits show instead a cultivar-specific behavior; in fact, stomata plasticity, photosynthetic pattern, and antioxidant power provide different responses, but only Spagnolo cv. achieves a successful strategy attaining a real resilience to metal stress. The capacity of Spagnolo plants to modify leaf structural and physiological traits under heavy metal contamination to maintain high photosynthetic efficiency should be considered an elective trait for its use in contaminated environments.

Revisiting the Krakatau 1883 Volcanic Aerosol Dispersal 

2021 ◽  
Author(s):  
Rafael Castro ◽  
Tushar Mittal ◽  
Stephen Self
Keyword(s):  
Climate Model ◽  
Global Climate ◽  
Global Climate Model ◽  
Volcanic Eruptions ◽  
Climate Impact ◽  
Volcanic Plume ◽  
Quasi Biennial Oscillation ◽  
Aerosol Cloud ◽  
Pinatubo Eruption ◽  
The Impact

&lt;p&gt;The 1883 Krakatau eruption is one of the most well-known historical volcanic eruptions due to its significant global climate impact as well as first recorded observations of various aerosol associated optical and physical phenomena. Although much work has been done on the former by comparison of global climate model predictions/ simulations with instrumental and proxy climate records, the latter has surprisingly not been studied in similar detail. In particular, there is a wealth of observations of vivid red sunsets, blue suns, and other similar features, that can be used to analyze the spatio-temporal dispersal of volcanic aerosols in summer to winter 1883. Thus, aerosol cloud dispersal after the Krakatau eruption can be estimated, bolstered by aerosol cloud behavior as monitored by satellite-based instrument observations after the 1991 Pinatubo eruption. This is one of a handful of large historic eruptions where this analysis can be done (using non-climate proxy methods). In this study, we model particle trajectories of the Krakatau eruption cloud using the Hysplit trajectory model and compare our results with our compiled observational dataset (principally using Verbeek 1884, the Royal Society report, and Kiessling 1884).&lt;/p&gt;&lt;p&gt;In particular, we explore the effect of different atmospheric states - the quasi-biennial oscillation (QBO) which impacts zonal movement of the stratospheric volcanic plume - to estimate the phase of the QBO in 1883 required for a fast-moving westward cloud. Since this alone is unable to match the observed latitudinal spread of the aerosols, we then explore the impact of an&amp;#160; umbrella cloud (2000 km diameter) that almost certainly formed during such a large eruption. A large umbrella cloud, spreading over ~18 degrees within the duration of the climax of the eruption (6-8 hours), can lead to much quicker latitudinal spread than a point source (vent). We will discuss the results of the combined model (umbrella cloud and correct QBO phase) with historical accounts and observations, as well as previous work on the 1991 Pinatubo eruption. We also consider the likely impacts of water on aerosol concentrations and the relevance of this process for eruptions with possible significant seawater interactions, like Krakatau. We posit that the role of umbrella clouds is an under-appreciated, but significant, process for beginning to model the climatic impacts of large volcanic eruptions.&lt;/p&gt;

scholarly journals Long-range transport of volcanic aerosol from the 2010 Merapi tropical eruption to Antarctica

2018 ◽  
Author(s):  
Xue Wu ◽  
Sabine Griessbach ◽  
Lars Hoffmann
Keyword(s):  
Long Range ◽  
Lower Stratosphere ◽  
Polar Vortex ◽  
Volcanic Eruptions ◽  
Long Range Transport ◽  
Volcanic Plume ◽  
Volcanic Aerosol ◽  
The South ◽  
Range Transport ◽  
The Antarctic

Abstract. Volcanic sulfate aerosol is an important source of sulfur for Antarctica where other local sources of sulfur are rare. Mid- and high latitude volcanic eruptions can directly influence the aerosol budget of the polar stratosphere. However, tropical eruptions can also enhance polar aerosol load following long-range transport. In the present work, we analyze the volcanic plume of a tropical eruption, Mount Merapi in October 2010, using the Lagrangian particle dispersion model Massive-Parallel Trajectory Calculations (MPTRAC), Atmospheric Infrared Sounder (AIRS) SO2 observations and Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) aerosol observations. We investigate the pathway and transport efficiency of the volcanic aerosol from the tropical tropopause layer (TTL) to the lower stratosphere over Antarctica. We first estimated the time- and height-resolved SO2 injection time series over Mount Merapi during the explosive eruption using the AIRS SO2 observations and a backward trajectory approach. Then the SO2 injections were tracked for up to 6 months using the MPTRAC model. The Lagrangian transport simulation of the volcanic plume was compared to MIPAS aerosol observations and showed good agreement. Both of the simulation and the observations presented in this study suggest that a significant amount of aerosols of the volcanic plume from the Merapi eruption was transported from the tropics to the south of 60 °S within one month after the eruption and even further to Antarctica in the following two months. This relatively fast meridional transport of volcanic aerosol was mainly driven by quasi-horizontal mixing from the TTL to the extratropical lower stratosphere, which was facilitated by the weakening of the subtropical jet during the seasonal transition from austral spring to summer and linked to the westerly phase of the quasi-biennial oscillation (QBO). When the plume went to southern high latitudes, the polar vortex was displaced from the south pole, so the volcanic plume was carried to the south pole without penetrating the polar vortex. Based on the model results, the most efficient pathway for the quasi-horizontal mixing was in between the isentropic surfaces of 360 and 430 K. Although only 4 % of the initial SO2 load was transported into the lower stratosphere south of 60 °S, the Merapi eruption contributed about 8800 tons of sulfur to the Antarctic lower stratosphere. This indicates that the long-range transport under favorable meteorological conditions enables tropical volcanic eruptions to be an important remote source of sulfur for the Antarctic stratosphere.

scholarly journals Increment in the volcanic unrest and number of eruptions after the 2012 large earthquakes sequence in Central America

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Gino González ◽  
Eisuke Fujita ◽  
Bunichiro Shibazaki ◽  
Takumi Hayashida ◽  
Giovanni Chiodini ◽  
...  
Keyword(s):  
Central America ◽  
Seismic Waves ◽  
Dynamic Stress ◽  
Reaction Times ◽  
Volcanic Eruptions ◽  
Large Magnitude ◽  
Tectonic Earthquakes ◽  
The Impact ◽  
The Relationship ◽  
Large Earthquakes

AbstractUnderstanding the relationship cause/effect between tectonic earthquakes and volcanic eruptions is a striking topic in Earth Sciences. Volcanoes erupt with variable reaction times as a consequence of the impact of seismic waves (i.e. dynamic stress) and changes in the stress field (i.e. static stress). In 2012, three large (Mw ≥ 7.3) subduction earthquakes struck Central America within a period of 10 weeks; subsequently, some volcanoes in the region erupted a few days after, while others took months or even years to erupt. Here, we show that these three earthquakes contributed to the increase in the number of volcanic eruptions during the 7 years that followed these seismic events. We found that only those volcanoes that were already in a critical state of unrest eventually erupted, which indicates that the earthquakes only prompted the eruptions. Therefore, we recommend the permanent monitoring of active volcanoes to reveal which are more susceptible to culminate into eruption in the aftermath of the next large-magnitude earthquake hits a region.

Impact of the Christmas 2018 Mount Etna Eruption on the Regional Air Quality

2021 ◽  
Author(s):  
Claire Lamotte ◽  
Jonathan Guth ◽  
Virginie Marécal ◽  
Giuseppe Salerno ◽  
Nicolas Theys ◽  
...  
Keyword(s):  
Air Quality ◽  
Regional Scale ◽  
Volcanic Eruptions ◽  
Mount Etna ◽  
Surface Measurement ◽  
Volcanic Plume ◽  
Observation Data ◽  
Sulfate Aerosols ◽  
Lower Altitude ◽  
The Impact

&lt;p&gt;&lt;span&gt;Volcanic eruptions are events that can eject several tons of material into the atmosphere. Among these emissions, sulfur dioxide is the main sulfurous volcanic gas. It can form sulfate aerosols that are harmful to health or, being highly soluble, it can condense in water particles and form acid rain. Thus, volcanic eruptions can have an environmental impact on a regional scale.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;&lt;span&gt;The Mediterranean region is very interesting from this point of view because it is a densely populated region with a strong anthropogenic activity, therefore polluted, in which Mount Etna is also located. Mount Etna is the largest passive SO&lt;sub&gt;2&lt;/sub&gt; emitter in Europe, but it can also sporadically produce strong eruptive events. It is then likely that the additional input of sulfur compounds into the atmosphere by volcanic emissions may have effects on the regional atmospheric sulfur composition.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;&lt;span&gt;We are particularly investigating the eruption of Mount Etna on December 24, 2018 [Corradini et al, 2020]. This eruption took place along a 2 km long breach on the side of the volcano, thus at a lower altitude than its main crater. About 100 kt of SO&lt;sub&gt;2&lt;/sub&gt; and 35 kt of ash were released in total, between December 24 and 30. With the exception of the 24th, the quantities of ash were always lower than the SO&lt;sub&gt;2.&lt;/sub&gt;&lt;/span&gt;&lt;/p&gt;&lt;p&gt;&lt;span&gt;The availability of the TROPOMI SO&lt;sub&gt;2&lt;/sub&gt;&lt;sub&gt;&lt;/sub&gt;&lt;/span&gt;&lt;span&gt;column &lt;/span&gt;&lt;span&gt;estimates, at fine &lt;/span&gt;&lt;span&gt;spatial&lt;/span&gt;&lt;span&gt; resolution &lt;/span&gt;&lt;span&gt;(7 km x 3.5 km at nadir) and &lt;/span&gt;&lt;span&gt;associated averaging kernels&lt;/span&gt;&lt;span&gt;,&lt;/span&gt;&lt;span&gt; during this eruptive period made it also an excellent case study. &lt;/span&gt;&lt;span&gt;It &lt;/span&gt;&lt;span&gt;allow&lt;/span&gt;&lt;span&gt;s&lt;/span&gt;&lt;span&gt; us to follow the evolution of SO&lt;sub&gt;2&lt;/sub&gt; in the volcanic plume over several days.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;&lt;span&gt;Using the CNRM MOCAGE chemistry-transport model (CTM), we aim to quantify the impact of this volcanic eruption on atmospheric composition, sulfur deposition and air quality at the regional scale. The comparison of the model with the TROPOMI observation data allows us to assess the ability of the model to properly represent the plume. In spite of a particular meteorological situation, leading to a complex plume transport, MOCAGE shows a good agreement with TROPOMI observations. Thus, from the MOCAGE simulation, we can evaluate the impact of the eruption on the regional concentrations of SO&lt;sub&gt;2&lt;/sub&gt; and sulfate aerosols, but also analyse the quantities of dry and wet deposition, and compare it to surface measurement stations.&lt;/span&gt;&lt;/p&gt;

The muesli effect in pyroclastic density currents - what does reverse grading in an ignimbrite mean? 

2021 ◽  
Author(s):  
Matthew Johnson ◽  
Natasha Dowey ◽  
Rebecca Williams ◽  
Pete Rowley
Keyword(s):  
Volcanic Eruptions ◽  
Volcanic Hazards ◽  
Transport Processes ◽  
Pyroclastic Density Currents ◽  
Density Currents ◽  
Static Tests ◽  
Grain Sizes ◽  
Unidirectional Flow ◽  
3D Architecture ◽  
The Relationship

&lt;p&gt;Pyroclastic density currents (PDCs) are hot, density-driven flows of gas, rock and ash generated during explosive volcanic eruptions, or from the collapse of lava domes (e.g. Fisher, 1979; Branney and Kokelaar, 2002; Cas et al. 2011). They pose a catastrophic geological hazard and have caused &gt;90 000 deaths since 1600AD (Auker et al. 2013). Improved understanding of PDCs will enable us to better understand the explosive eruptions that generate them, improving our preparedness for future volcanic events. However, these deadly hazards are rarely observed up close and are difficult to analyse in real-time. To understand the flow dynamics of density currents we must use models and interpretations of their deposits (e.g. Smith N and Kokelaar, 2013; Rowley et al. 2014, Williams et al. 2014, Sulpizio et al. 2014; Lube et al. 2019, Smith G 2018, 2020).&lt;/p&gt;&lt;p&gt;The deposits of pyroclastic density currents, known as &amp;#8216;ignimbrites&amp;#8217; can reveal important clues about how these deadly volcanic hazards behave in time and space Reverse grading in an ignimbrite can be interpreted in different ways (Branney &amp; Kokelaar, 2002). It could record a growing eruption intensity through time - where increasingly larger clasts are introduced into the pyroclastic density current. Alternatively, it could record Kinematic sorting (the &amp;#8216;muesli effect&amp;#8217;) and transport processes within the current where larger particles became increasingly likely to be deposited as the current wanes (Palladino &amp; Valentine,1995). The link between current dynamics and reverse grading is currently untested in aerated granular currents.&lt;/p&gt;&lt;p&gt;This project seeks to investigate the relationship between current dynamics and deposit architecture, specifically by considering granular sorting mechanisms in unidirectional flow. We will use an analogue flume (following methods in Rowley et. al., 2014, and Smith G et al., 2018, 2020) to explore how reverse grading and lateral grading may be related to changes in grain sizes at source versus kinematic sorting processes. A mix of grain sizes will be incorporated into the current via a hopper which allows for the starting composition of the current to be varied e.g. homogenous mix versus layered. Photographs of the deposit will be taken through the transparent sidewall of the flume and analysed using image analysis software. These experiments will be complimented by static tests of kinematic sorting, where a Perspex column will be sliced to reveal internal 3d architecture. This project will contribute to our understanding of lithofacies architecture in the field, and help to quantity how we interpret the sedimentation of ignimbrites.&lt;/p&gt;&lt;p&gt;&lt;em&gt;References&lt;/em&gt;&lt;/p&gt;&lt;p&gt;Auker et al. (2013) https://doi.org/10.1186/2191-5040-2-2&lt;/p&gt;&lt;p&gt;Branney and Kokelaar (2002) https://doi.org/10.1144/GSL.MEM.2003.027&lt;/p&gt;&lt;p&gt;Cas et al. (2011) Bulletin of Volcanology 731583 https://doi.org/10.1007/s00445-011-0564-y&lt;/p&gt;&lt;p&gt;Fisher (1979) https://doi.org/10.1016/0377- 0273(79)90008-8&amp;#160; &amp;#160;&amp;#160;&lt;/p&gt;&lt;p&gt;Lube et al. (2019) https://doi.org/10.1038/s41561-019-0338-2&lt;/p&gt;&lt;p&gt;Palladino &amp; Valentine (1995). https://doi.org/10.1016/0377-0273(95)00036-4&lt;/p&gt;&lt;p&gt;Rowley et al. (2014) https://doi.org/10.1007/s00445-014-0855-1&lt;/p&gt;&lt;p&gt;Smith N. and Kokelaar (2013) https://doi.org/10.1007/s00445-013-0768-4&lt;/p&gt;&lt;p&gt;Smith G. et al. (2018) https://doi.org/10.1007/s00445-018-1241-1&lt;/p&gt;&lt;p&gt;Smith, G. et al. (2020). https://doi.org/10.1038/s41467-020-16657-z&lt;/p&gt;

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