Volcanic Eruptions In Iceland Research Articles

Stakeholder perceptions of managing an emergent tourist destination: the Fagradalsfjall volcanic eruption in Iceland.

The 2021 volcanic eruption at Fagradalsfjall, Iceland, provides a case study for examining an active collaboration between stakeholders in the development of an emergent volcanic site into a tourism destination from its inception. Stakeholders for this research include municipal actors and representatives; landowners; commercial tour companies and operators; the Federal Ministry of Tourism and Ministry of Environment and Natural Resources, civil protection, and search and rescue. These stakeholder perceptions of the management process are analyzed within a responsible and sustainable tourism framework by a constant comparative method of interview text. The results bring to light issues deemed important during the site management and destination development process around concepts of authority, responsibility, safety, funding, and access. According to stakeholders, the management of the emergent Fagradalsfjall destination while positively perceived initially has gaps surrounding ongoing sustainable and responsible management that could have impacts on the participation of various stakeholder groups in the destination's ongoing development. This research has implications for other emergent volcanic tourist sites in Iceland and beyond.

Psychological impact of a volcano eruption − Mount Nyiragongo

The volcanic eruption is a rather uncommon type of natural disaster and is restricted to certain geographical regions. The psychological distress studied among the evacuees of a volcano in many countries revealed symptoms of anxiety, insomnia, anergia, social dysfunction, and anhedonia persisting even after six months of eruption. A study after a volcanic eruption in Iceland revealed higher incidence of mental distress and post-traumatic stress disorder (PTSD) in exposed versus the non-exposed groups. Insomnia, psychological morbidity, and possible long-term psychological morbidity were reported as the most common symptoms in the high-exposure group (based on the volcano-ash fall). Studies also show the involvement of children’s mental health. DRC, being a low-income country lacks the research and does not have strongly researched data regarding the prevalence of psychological morbidity post the volcano eruption. However, the psychological maladjustments after the Mount Nyiragongo eruption in 2002 were reported as the major health consequence as per WHO. This paper analyses the various psychological aspects during and after a volcanic eruption.

The Evolution of Icelandic Volcano Emissions, as Observed From Space in the Era of NASA's Earth Observing System (EOS)

AbstractVolcanoes are natural phenomena that have global environmental impacts. Satellite remote sensing can help classify volcanic eruptions and track the dispersion of emissions. We assess multiple volcanic eruptions in Iceland (Eyjafjallajökull 2010, Grímsvötn 2011, and Holuhraun 2014–2015), using space‐borne observations to infer information about the geological dynamics of each volcano and the properties and evolution of plume particles. We derive qualitative constraints on plume particle size, shape, and light‐absorption characteristics from Multiangle Imaging SpectroRadiometer (MISR) space‐borne imagery. With the MISR Research Algorithm (RA), we distinguish sulfate/water‐dominated volcanic plumes from Holuhraun and ash‐dominated plumes from Eyjafjallajökull and Grímsvötn, and even identify subtler changes in ash particle size and light‐absorption within plumes. Additionally, plume heights are retrieved geometrically from MISR. These are combined with surface thermal anomalies from the MODerate resolution Imaging Spectroradiometer (MODIS) and SO2 concentrations derived from the Ozone Monitoring Instrument (OMI) to synthesize eruption remote‐sensing chronologies. Signals related to differences in particle properties are identified and linked to evolving magma composition at Eyjafjallajökull. The results illustrate the potential to distinguish qualitative differences in eruptive magma composition based on particle light absorption and plume profile from remote‐sensing. For the sulfate‐rich Holuhraun plumes, the influence of aerosol hygroscopic growth during transport is inferred from such data. Three processes appear to dominate plume evolution in Iceland: downwind aerosol formation, particle hydration, and particle deposition. This work demonstrates enhanced MISR capabilities and, more generally, remote‐sensing analysis that can be applied globally, especially where suborbital volcano observations are limited or entirely absent.

Hekla 1947, 1845, 1510 and 1158 tephra in Finland: challenges of tracing tephra from moderate eruptions

ABSTRACTSeveral cryptotephra layers that originate from Icelandic volcanic eruptions with a volcanic explosivity index (VEI) of ≤ 4 and tephra volumes of < 1 km3 have previously been identified in Northern Europe, albeit within a restricted geographical area. One of these is the Hekla 1947 tephra that formed a visible fall‐out in southern Finland. We searched for the Hekla 1947 tephra from peat archives within the previously inferred fall‐out zone but found no evidence of its presence. Instead, we report the first identification of Hekla 1845 and Hekla 1510 cryptotephra layers outside of Iceland, the Faroe Islands, Ireland and the UK. Additionally, Hekla 1158 tephra was found in Finland for the first time. Our results confirm that Icelandic eruptions of moderate size can form cryptotephra deposits that are extensive enough to be used in inter‐regional correlations of environmental archives and carry a great potential for refining regional tephrochronological frameworks. Our results also reveal that Icelandic tephra has been dispersed into Finnish airspace at least seven times during the past millennium and in addition to a direct eastward route the ash clouds can travel either via a northerly or a southerly transport pathway.

A test of oscillation in the human secondary sex ratio.

Background and objectivesThe sex ratio of human birth cohorts predicts the health and longevity of their members. Most literature invokes natural selection in support of the argument that heritable tendencies to produce male or female offspring induce oscillation in the sex ratio and its sequelae. Tests of the argument remain exceedingly rare because they require vital statistics describing many generations of a population both unaffected by migration and exposed to an exogenous stressor virulent enough to change the sex ratio at birth. We contribute to the literature by using time-series modeling to detect oscillation in the best data currently available for such a test.MethodologyWe apply rigorous time-series methods to data describing Sweden from 1751 through 1830, a period when the population not only aged in place without migration, but also exhibited the effects of an Icelandic volcanic eruption including a historically low secondary sex ratio. That very low sex ratio should have induced oscillation if heritable mechanisms appear in humans.ResultsWe detected oscillation in the ratio but not that predicted by heritable tendencies to produce males or females. We found peak-to-trough oscillation at 14 rather than the approximately 32 years expected from the heritable tendencies argument.Conclusions and implicationsOur findings suggest that mechanisms other than perturbation of heritable tendencies to produce males or females induce oscillation in the human secondary sex ratio. These other mechanisms may include reproductive suppression and selection in utero.LAY SUMMARYThe male to female ratio in human birth cohorts predicts longevity but its variation over time remains unexplained. We test the long-held theory that the ratio oscillates due to heritable tendencies to produce males or females. We find oscillation, but it appears due to social processes rather than heritable mechanisms.

Rhyolitic and dacitic component of the Askja 1875 tephra in southern and central Finland: first step towards a Finnish tephrochronology

ABSTRACTTephra from Icelandic volcanic eruptions is frequently dispersed to northern Europe, but so far tephra has not been detected in Finnish sedimentary records. We report the first finding of a cryptotephra layer in southern and central Finland. Sediment samples from five lakes and 10 peatlands, most of them located in the tephra fallout zone of the Hekla 1947 eruption, were investigated for the presence of cryptotephra to assess the potential for tephrochronology in Finland. Tephra shards were extracted from their host matrix and electron probe microanalysis was conducted on single shards for geochemical characterization. Our results confirm the presence of Askja 1875 tephra in Finland, thus extending the known dispersal area of the Askja 1875 tephra eastwards. Most of the shards are rhyolitic, but a minor concentration of tephra with dacitic composition forms a narrow dispersal zone extending from Sweden to southern Finland. This zone possibly represents the main dispersal axis of the tephra in the distal area. Our results suggest that Finnish environmental research could benefit greatly from adding tephrochronology to the array of dating methods commonly used. Additionally, the absence of Hekla 1947 tephra in the previously inferred fall‐out zone is an important result indicating the complexity of tephra deposition and preservation.

Promotion of Interdisciplinary and Transdisciplinary Collaboration in Disaster Risk Reduction

This paper describes interdisciplinary and transdisciplinary approaches inevitably necessary for effective disaster risk management, introducing examples involving the tsunami hazard map in Sendai, volcanic eruption in Iceland, and river flooding in Thailand. On the basis of the conversations conducted at the Global Forum on Science and Technology for Disaster Resilience 2017 held at the Science Council of Japan in Tokyo on November 23–25, 2017, this paper summarizes the results of the discussion for further development of these approaches. Some international initiatives are also briefly introduced.

Responding to volcanic eruptions in Iceland: from the small to the catastrophic

There is no doubt that as the world’s population continues to grow and expand in hazardous environments, so too does our vulnerability to disaster. Researching disaster risk is therefore an ongoing challenge requiring a continual process of generating understanding of the changing environmental and societal characteristics that influence disaster vulnerability. Iceland, as the land of fire and ice, is of no exception. With a changing population, exponential growth in tourism and a volcanic eruption on average every 3–4 years, disaster risk research is of critical importance. Based on questionnaire survey results, interviews with key stakeholders and data derived from Statistics Iceland, this paper considers how residents might respond to a future eruption by examining their experience of the 2010 Eyjafjallajökull eruptions against the changing demographic, economic and political landscape. While authorities were pleased with public response to evacuation orders in 2010, some residents did not evacuate. The reasons for not evacuating were due to caring for others or thinking the warnings were not applicable. Yet, most residents showed respect for authority and acknowledged the necessity of the evacuations. The relatively small, homogenous population of Iceland coupled with its peoples’ desire to cooperate contributed to this success. Within these communities, people are bound together by common beliefs, values and activities. However, the changing social landscape will test this phenomenon. In particular, the region’s economic base is evolving from traditional farming practices to one that is increasingly reliant on tourism. Demographic changes most notably include greater international migration to the South, as well as from the capital region. As the communities diversify, so too will people’s beliefs, values and activities. This paper explores the challenges this diversity brings with respect to generating a proactive public response to future evacuation orders. Furthermore, it highlights the importance of capturing narratives of actions and activities to enhance our understanding of the process of decision-making and the situational factors that add to its complexity.

REFIR- A multi-parameter system for near real-time estimates of plume-height and mass eruption rate during explosive eruptions

Meaningful forecasting of the atmospheric concentration and ground accumulation of volcanic ash during explosive eruptions requires detailed knowledge of the eruption source parameters. However, due to the large uncertainties in observations and limitations of current models used to make inferences from these, monitoring an ongoing eruption and quantifying the mass eruption rate in real-time is a considerable challenge. Within the EU supersite project “FutureVolc”, an integrated approach has been applied to develop a quasi-autonomous multi-parameter system, denoted “REFIR”, for monitoring volcanic eruptions in Iceland and assessing the eruption mass flow rate by inverting the plume height information and taking account of these uncertainties. REFIR has the capability to ingest and process streaming plume-height data provided by a multitude of ground based sensors, including C– and X-band radars and web-cam based plume height tracking systems. These observational data are used with a suite of plume models that also consider the current wind and other atmospheric conditions, providing statistically assessed best estimates of plume height and mass eruption rate. Provided instrumental data is available, near real-time estimates are obtained (the delay corresponding to the scan rate of data-providing instruments, presently of the order of minutes). Using the Hekla 2000, and Eyjafjallajökull 2010 eruptions in Iceland, the potential of REFIR is demonstrated and discussed through application to three scenarios. The system has been developed to provide maximum flexibility. A setup script assists the user in adapting to local conditions, allowing implementation of REFIR for any volcanic eruption site worldwide. REFIR is designed to be easily upgradable, allowing future extension of monitoring networks, learning from new events, and incorporation of new technologies and model improvements. This article gives an overview of the basic structure, models implemented, functionalities and the computational techniques of REFIR.

Mental health effects following the eruption in Eyjafjallajökull volcano in Iceland: A population-based study.

Volcanic eruptions and other natural disasters may affect survivor's physical and mental health. The aim of this study was to examine the mental health effects of the 2010 Eyjafjallajökull volcanic eruption in Iceland on nearby residents, by exposure level and experience. This population-based study included 1615 residents living in an area close to the Eyjafjallajökull volcano at the time of the eruption and a sample of 697 residents from a non-exposed area. All participants received a questionnaire 6-9 months after the eruption assessing mental health (GHQ-12, PSS-4 and PC-PTSD). The exposed group also received questions related to the experience of the eruption. Replies were received from 1146 participants in the exposed group (71%) and 510 participants in the non-exposed group (73%). Compared to the non-exposed group, participants living in the high-exposed area were at increased risk of experiencing mental distress (GHQ) 6-9 months following the eruption (odds ratio (OR) 1.45%; 95% confidence interval (CI) 1.11-1.90). High-exposed participants were furthermore at increased risk of experiencing symptoms of post-traumatic stress disorder (PTSD) compared to those living in the low-exposed area (OR 3.71; 95% CI 1.34-15.41). We further found that those who had direct experience of the eruption were more likely to suffer from symptoms of mental distress, PTSD symptoms and perceived stress, compared to those less exposed. The findings indicate that screening for these factors (e.g. experience of the event) could potentially aid in identifying those most vulnerable to developing psychological morbidity after this unique type of disaster.

Climatic control on Icelandic volcanic activity during the mid-Holocene

Human-induced climate change is causing rapid melting of ice in many volcanically active regions. Over glacial-interglacial time scales changes in surface loading exerted by large variations in glacier size affect the rates of volcanic activity. Numerical models suggest that smaller changes in ice volume over shorter time scales may also influence rates of mantle melt generation. However, this effect has not been verified in the geological record. Furthermore, the time lag between climatic forcing and a resultant change in the frequency of volcanic eruptions is unknown. We present empirical evidence that the frequency of volcanic eruptions in Iceland was affected by glacial extent, modulated by climate, on multicentennial time scales during the Holocene. We examine the frequency of volcanic ash deposition over northern Europe and compare this with Icelandic eruptions. We identify a period of markedly reduced volcanic activity centered on 5.5–4.5 ka that was preceded by a major change in atmospheric circulation patterns, expressed in the North Atlantic as a deepening of the Icelandic Low, favoring glacial advance on Iceland. We calculate an apparent time lag of ∼600 yr between the climate event and change in eruption frequency. Given the time lag identified here, increase in volcanic eruptions due to ongoing deglaciation since the end of the Little Ice Age may not become apparent for hundreds of years.

Effects of the Hekla 4 tephra on vegetation in Northwest Iceland

Vegetation plays a key role in preventing the remobilisation of tephra and aeolian activity following tephra fall. Recent volcanic eruptions in Iceland have highlighted the consequences of tephra fall for ecosystems and human health. Improved understanding of the mechanisms behind ecosystem recovery following tephra fall is particularly important for Iceland. Today ~42% of the country is classified as desert and unvegetated and sparsely vegetated areas are unable to trap tephra fall and prevent subsequent wind erosion. This paper presents palaeoenvironmental reconstructions before and after the Hekla 4 tephra from two lakes in Northwest Iceland, from within a woodland in the lowland, and in open woodland under stress at the highland margin. The c. 4,200 cal bp. Hekla 4 tephra is one of the most extensive Icelandic Holocene tephra layers and the eruption produced an estimated ~9 km3 of tephra. The palaeoecological reconstructions provide an insight into the responses of two relatively stable ecosystems to thick tephra deposits during a period of cooling climate. The understory vegetation in the lowland woodland was buried by the tephra, however Betula pubescens trees were not severely affected and the woodland recovered relatively quickly. In contrast, open woodland at the highland margin that was already at its ecological limit, shifted to dwarf shrub heath, a more resilient vegetation community in response to the tephra fall and cooling climate.

Local surface mass-balance reconstruction from a tephra layer – a case study on the northern slope of Mýrdalsjökull, Iceland

ABSTRACTMost Icelandic glaciers show high-accumulation rates during winter and strong surface melting during summer. Although it is difficult to establish and maintain mass-balance programs on these glaciers, mass-balance series do exist for several of the ice caps (Björnsson and others, 2013). We make use of the frequent volcanic eruptions in Iceland, which cause widespread internal tephra layers in the ice caps, to reconstruct the surface mass balance (SMB) in the ablation zone. This method requires information about surface geometry and ice velocity, derived from remote-sensing information. In addition, the emergence angle of the tephra layer needs to be known. As a proof-of-concept, we utilize a prominent tephra layer of the Mýrdalsjökull Ice Cap to infer local SMB estimates in the ablation area back to 1988. Using tephra-layer outcrop locations across the glacier at different points in time it is possible to determine local mass changes (loss and redistribution) for a large part of the ablation zone, without the use of historic elevation models, which often are not available.

Gradual caldera collapse at Bárdarbunga volcano, Iceland, regulated by lateral magma outflow.

Large volcanic eruptions on Earth commonly occur with a collapse of the roof of a crustal magma reservoir, forming a caldera. Only a few such collapses occur per century, and the lack of detailed observations has obscured insight into the mechanical interplay between collapse and eruption. We use multiparameter geophysical and geochemical data to show that the 110-square-kilometer and 65-meter-deep collapse of Bárdarbunga caldera in 2014-2015 was initiated through withdrawal of magma, and lateral migration through a 48-kilometers-long dike, from a 12-kilometers deep reservoir. Interaction between the pressure exerted by the subsiding reservoir roof and the physical properties of the subsurface flow path explain the gradual, near-exponential decline of both collapse rate and the intensity of the 180-day-long eruption.

Framing the 2010 Eyjafjallajökull volcanic eruption from a farming-disaster perspective

The aim of this paper was to shed light on the 2010 Eyjafjallajokull volcanic eruption in Iceland from a farming perspective to identify lessons for livelihood professions regarding disasters. Scientists had detected activity under the volcano for over a decade prior to the eruption and had notified the Civil Protection. Preparedness activities included disaster planning and training in evacuation procedures in the event of flooding caused by an eruption under the Eyjafjallajokull icecap. However, the main concern for farmers turned out to be ashfall. Previous research has shown that specialized information to farmers on ashfall was inadequate. Here, information is presented from a livelihood-disaster perspective and used as a basis for an analysis of pre-eruption, real-time and post-eruption activities by farming actors. The livelihood-disaster perspective is built on the Sustainable Livelihoods Framework and a set of eight disaster-related objectives. The study shows that farming actors were not informed about the scientific monitoring, not included in pre-eruption coordination by the Civil Protection but were indeed the main actors responding to the needs of farmers having ash problems in the weeks and months following the eruption. A literature survey shows that sufficient hazard, exposure and vulnerability information had been available prior to the eruption to produce useful risk-related information to inform risk reduction and contingency planning amongst farming actors. Livelihood professionals are highly specialized and should take the initiative in performing their own pre-disaster activities to effectively and efficiently assist their communities during a disaster.

Effect of volcanic ash on GHG production rates and soil properties in a drained peat soil compared to wood ash

INTRODUCTION Past volcanic eruptions in Iceland have sometimes led to long-distance distribution of fine volcanic tephra (volcanic ash). Evidence for volcanic ash from, for example, the ca. 4250 BP eruption in Hekla (H4) and the 17831784 AD Laki eruption in southern Iceland has been found in wetlands at Svalbard (Kekonen et al. 2005), Scotland (Charman et al. 1995) and Scandinavia (Thorarinsson 1981). Basaltic volcanic ash contains several compounds, e.g. mixed sulphates, ammonium (NH4 +) and nitrate (NO3 -) (Ayris and Delmelle 2012), all of which have the potential to affect various soil processes, such as N cycling and greenhouse gas (GHG) production. Such direct effects of long distance volcanic ash transport have, however, been little studied so far. The Eyjafjallajokull volcano eruption started in Iceland in March, 2010. A major outbreak of the central crater under the covering ice cap started on 14 April and continued until 24 May, ejecting a very large amount of gases and fine ash into the atmosphere. This ash contained mainly silicon dioxide, but also other compounds including sulphates (O’Dowd et al. 2012). This eruption gave us an opportunity to study the fresh volcanic ash and its effects on soil properties. Because this volcanic ash was alkaline, it could increase soil pH and affect the microbiological processes behind GHG emissions in a similar way to that suggested for wood ash (Maljanen et al. 2014, Klemedtsson et al. 2010). We used fresh volcanic ash from the Eyjafjallajokull volcano in a laboratory experiment conducted on samples of drained peat soil from western Finland that were also used for studying the effects of wood ash recycling from bioenergy power plants (Maljanen et al. 2014). The aim of this study was to test whether this volcanic ash affected GHG production rates in drained peat soil in our laboratory incubation experiments and to compare the results with wood ash.

Real-time monitoring of volcanic eruptions in Iceland 2004–2014 using satellite images

Real-time monitoring of volcanic eruptions in Iceland, using satellite remote sensing, has expanded during the last decade. Availability of satellite images has increased extensively in the last few years, with improved geometric, radiometric, and time resolution, in addition to shortened delivery time. This paper provides an overview and a brief historical perspective of the topic.

Coupled effects on Kenyan horticulture following the 2008/2009 post-election violence and the 2010 volcanic eruption of Eyjafjallajökull

Natural disasters can cause significant economic impacts impeding growth and development of local sectors. In sub-Saharan Africa, the effects may intensify following social–political unrest and unstable governance. Interestingly, though uncommon, both happenings took place consecutively causing huge economic meltdown on the horticulture sub-sector in Kenya. This paper evaluates the impacts of two events: (1) the 2008 post-election violence in Kenya and (2) the 2010 Icelandic volcanic eruption on the Kenyan horticultural exports. Long-term annual and monthly trends in export volume for cut-flower, vegetables and fruits (export cluster) over a 19-year period are examined to establish impacts of both events on horticulture exports. The performance of the three export clusters are examined, highlighting underlying seasonal variations in export volume in the last ~2 decades. Results show positive trends in all three commodities, until 2008/2009, where the trend declines continuously hitting lowest volume in 2010, particularly the month of December which coincides with a rainy, low production season. There are significant differences in export volumes between the groups (F = 63.08, p < 0.001, Fcritical = 3.316). Cut-flowers lead in export, followed by vegetables and fruits. Characteristic seasonal peaks occur for vegetables and fruits, unlike cut-flowers which show continuous year round production. Interestingly, the annual average fruit exports increased (cut-flowers and vegetables decreased) during and after the two events, a trend not observed previously. The findings of the current study present important lessons that can help initiate a discussion on suitable needed changes within the horticulture sub-sector, to aid sustainable development of the local economies.

A multi-scale risk assessment for tephra fallout and airborne concentration from multiple Icelandic volcanoes – Part 1: Hazard assessment

Abstract. In order to assist the elaboration of proactive measures for the management of future volcanic eruptions in Iceland, we developed a new scenario-based approach to assess the hazard associated with tephra dispersal and sedimentation at various scales and for multiple sources. The target volcanoes are Hekla, Katla, Eyjafjallajökull and Askja, selected either for their high probabilities of eruption and/or their high potential impact. By coupling tephrostratigraphic studies, probabilistic techniques and modelling, we developed comprehensive eruption scenarios for both short- and long-lasting eruptions and compiled hazard maps for tephra ground deposition at a national scale and air concentration at a European scale using the TEPHRA2 and FALL3D models, respectively. New algorithms for the identification of realistic sets of eruptive source parameters are investigated, which assist the generation of probability density functions of eruption source parameters for the selected scenarios. Aggregation processes were accounted for using various empirical models. Outcomes, i.e. probabilities conditioned to the occurrence of an eruption, help the assessment and comparison of hazard levels at different scales. For example, at a national scale Askja has a 5–10% probability of blanketing the easternmost half of the country with a tephra accumulation of at least 1 kg m−2. At a continental scale, Katla has a 5–10% probability of producing ash clouds with concentrations of 2 mg m−3 over the UK, Scandinavia and northern Europe with a mean arrival time of 48–72 h and a mean persistence time of 6–18 h. In a companion paper, Scaini et al. (2014) present a vulnerability assessment for Iceland to ground deposition of tephra and for the European air traffic to airborne ash which, combined with the outcomes of the present paper, constitute one of the first comprehensive multi-scale risk assessment associated with tephra dispersal and sedimentation.

Physical and remineralization processes govern the cobalt distribution in the deep western Atlantic Ocean

Abstract. The distributions of the bio-essential trace element dissolved cobalt (DCo) and the apparent particulate Co (PCo) are presented along the GEOTRACES-A02 deep section from 64° N to 50° S in the western Atlantic Ocean (longest section of international GEOTRACES marine environment program). PCo was determined as the difference between total cobalt (TCo, unfiltered samples) and DCo. DCo concentrations ranged from 14.7 pM to 94.3 pM, and PCo concentrations from undetectable values to 18.8 pM. The lowest DCo concentrations were observed in the subtropical domains, and the highest in the low-oxygenated Atlantic Central Waters (ACW), which appears to be the major reservoir of DCo in the western Atlantic. In the Antarctic Bottom Waters, the enrichment in DCo with aging of the water mass can be related to suspension and redissolution of bottom sediments a well as diffusion of DCo from abyssal sediments. Mixing and dilution of deep water masses, rather than scavenging of DCo onto settling particles, generated the meridional decrease of DCo along the southward large-scale circulation in the deep western Atlantic. Furthermore, the apparent scavenged profile of DCo observed in the deep waters likely resulted from the persistence of relatively high concentrations in intermediate waters and low DCo concentrations in underlaying bottom waters. We suggest that the 2010 Icelandic volcanic eruption could have been a source of DCo that could have been transported into the core of the Northeast Atlantic Deep Waters. At intermediate depths, the high concentrations of DCo recorded in the ACW linearly correlated with the apparent utilization of oxygen (AOU), indicating that remineralization of DCo could be significant (representing up to 37% of the DCo present). Furthermore, the preferential remineralization of phosphate (P) compared to Co in these low-oxygenated waters suggests a decoupling between the deep cycles of P and Co. The vertical diffusion of DCo from the ACW appears to be a significant source of DCo into the surface waters of the equatorial domain. Summarizing, the dilution due to mixing processes rather than scavenging of DCo and the above-mentioned remineralization could be the two major pathways controlling the cycling of DCo into the intermediate and deep western Atlantic.