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3. Demographic reconstruction from ancient DNA supports rapid extinction of the great auk.

Author

Thomas, Jessica E, Carvalho, Gary R, Haile, James, Rawlence, Nicolas J, Martin, Michael D, Ho, Simon Yw, Sigfússon, Arnór Þ, Jósefsson, Vigfús A, Frederiksen, Morten, Linnebjerg, Jannie F, Samaniego Castruita, Jose A, Niemann, Jonas, Sinding, Mikkel-Holger S, Sandoval-Velasco, Marcela, Soares, André Er, Lacy, Robert, Barilaro, Christina, Best, Juila, Brandis, Dirk, Cavallo, Chiara, Elorza, Mikelo, Garrett, Kimball L, Groot, Maaike, Johansson, Friederike, Lifjeld, Jan T, Nilson, Göran, Serjeanston, Dale, Sweet, Paul, Fuller, Errol, Hufthammer, Anne Karin, Meldgaard, Morten, Fjeldså, Jon, Shapiro, Beth, Hofreiter, Michael, Stewart, John R, Gilbert, M Thomas P, and Knapp, Michael

Subjects
Animals, Humans, DNA, Mitochondrial, Population Dynamics, Phylogeny, Charadriiformes, Extinction, Biological, Genome, Mitochondrial, Genetic Variation, DNA, Ancient, 19th century extinction, ancient DNA, evolutionary biology, genetics, genomics, hunting, paleogenetics, seabird exploitation, Life on Land, Biochemistry and Cell Biology
Abstract

The great auk was once abundant and distributed across the North Atlantic. It is now extinct, having been heavily exploited for its eggs, meat, and feathers. We investigated the impact of human hunting on its demise by integrating genetic data, GPS-based ocean current data, and analyses of population viability. We sequenced complete mitochondrial genomes of 41 individuals from across the species' geographic range and reconstructed population structure and population dynamics throughout the Holocene. Taken together, our data do not provide any evidence that great auks were at risk of extinction prior to the onset of intensive human hunting in the early 16th century. In addition, our population viability analyses reveal that even if the great auk had not been under threat by environmental change, human hunting alone could have been sufficient to cause its extinction. Our results emphasise the vulnerability of even abundant and widespread species to intense and localised exploitation.

Published
2019

4. Herbivore species coexistence in changing rangeland ecosystems: First high resolution national open-source and open-access ensemble models for Iceland

Author

Boulanger-Lapointe, Noémie, Ágústsdóttir, Kristín, Barrio, Isabel C., Defourneaux, Mathilde, Finnsdóttir, Rán, Jónsdóttir, Ingibjörg Svala, Marteinsdóttir, Bryndís, Mitchell, Carl, Möller, Marteinn, Nielsen, Ólafur Karl, Sigfússon, Arnór Þórir, Þórisson, Skarphéðinn G., and Huettmann, Falk

Published
2022
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9. Early cardiomyopathy without severe metabolic dysregulation in a patient with cblB‐type methylmalonic acidemia

Author

Dagbjört Agnarsdóttir, Vaka Kristín Sigurjónsdóttir, Arna Rut Emilsdóttir, Erna Petersen, Gunnlaugur Sigfússon, Ingólfur Rögnvaldsson, Leifur Franzson, Hilary Vernon, and Hans Tomas Bjornsson

Subjects
cblB, dilated cardiomyopathy, heart failure, MMAB, Genetics, QH426-470
Abstract

Abstract Background Cardiomyopathy is a known complication of organic acidemias but generally thought to be secondary to poor metabolic control. Methods Our patient was found through biochemical testing and Sanger sequencing to harbor an Icelandic founder mutation: NM_052845.4(MMAB):c.571C > T(p.Arg191Trp), leading to an early presentation (4 h after birth) of cblB‐type methylmalonic acidemia (MMA). Biochemical testing of this patient suggested B‐12‐responsiveness and thus the patient was treated with cyanocobalamin throughout life. Informed parental consent was obtained for this report. Results Our patient had three metabolic decompensations in her life (at birth, at 1 month, and at 5 months). The first decompensation was probably linked to stress of delivery, second to rhinovirus infection, and third by co‐infection of norovirus and enterovirus. At 3 months, the patient was noted to be tachypneic, although this was attributed to her underlying metabolic acidosis. At 5 months and 10 days, the patient was admitted with minor flu‐like symptoms but developed severe diarrhea in hospital and upon rehydration had cardiac decompensation and was found to have undiagnosed dilated cardiomyopathy. Although, patient was treated aggressively with dextrose, hemodialysis, levocarnitine, and vasoactive agents, there was limited response to medications to treat cardiac failure, and eventually the patient passed away before turning 6 months old. Conclusions Other than these three mild decompensations, patient had very good metabolic control, thus demonstrating that even without frequent metabolic decompensation, cardiomyopathy can be an observed phenotype in cblB‐type MMA even very early in life, suggesting that this phenotype may be independent of metabolic control.

Published
2022
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16. Using stable Mg isotope signatures to assess the fate of magnesium during the in situ mineralisation of CO2 and H2S at the CarbFix site in SW-Iceland

Author

Oelkers, Eric H., Butcher, Rhiannon, Pogge von Strandmann, Philip A.E., Schuessler, Jan A., von Blanckenburg, Friedhelm, Snæbjörnsdóttir, Sandra Ó., Mesfin, Kiflom, Aradóttir, Edda Sif, Gunnarsson, Ingvi, Sigfússon, Bergur, Gunnlaugsson, Einar, Matter, Juerg M., Stute, Martin, and Gislason, Sigurdur R.

Published
2019
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17. Rapid CO2 mineralisation into calcite at the CarbFix storage site quantified using calcium isotopes

Author

Philip A. E. Pogge von Strandmann, Kevin W. Burton, Sandra O. Snæbjörnsdóttir, Bergur Sigfússon, Edda S. Aradóttir, Ingvi Gunnarsson, Helgi A. Alfredsson, Kiflom G. Mesfin, Eric H. Oelkers, and Sigurður R. Gislason

Subjects
Science
Abstract

At the CarbFix experimental site in Iceland, artificial removal of CO2 from the Earth’s atmosphere is investigated. The authors here propose a new method based on isotope fractionation calculations to estimate the efficiency of CO2 sequestration into calcite in basaltic groundwater settings.

Published
2019
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19. Reactive transport of arsenic through basaltic porous media

Author

Sigfússon, Bergur

Subjects
551.9, Arsenic, Volcanism, Geothermal resources
Abstract

This thesis studied the volcanic and geothermal source of arsenic (As) and its fate in shallow ground waters and upon entering the ocean by means of experimental and field measurements combined with geochemical modeling. Arsenic enters the atmosphere and hydrosphere from degassing magmas and during volcanic eruptions. The November 2004 eruption within the Vatnajökull Glacier, Iceland, provided an opportunity to study elemental fluxes from volcanic eruptions into the environment. According to geochemical modeling, lowering of pH due to magma gases during the eruption led to rapid tephra dissolution with corresponding change in flood water chemistry. Geochemical modeling of floodwater/seawater mixing indicated localised decrease in dissolved arsenic and sulphur due to adsorption on the suspended floodwater materials. As the floodwater was diluted the As desorbed and limited effect of the floodwater was predicted after thousand fold dilution. Laboratory experiments were carried out to generate and validate sorption coefficients for arsenite and arsenate in contact with basaltic glass at pH 3 to 10. The mobility of arsenite decreased with increasing pH. The opposite was true for arsenate, being nearly immobile at pH 3 to being highly mobile at pH 10. A 1D reactive transport model constrained by a long time series of field measurements of chemical composition of geothermal effluent fluids from a powerplant was constructed. Thioarsenic species were the dominant form of dissolved As in the waters exiting the power plant but converted to some extent to arsenite and arsenate before feeding into a basaltic lava field. Chloride, moved through the basaltic lava field (4100 m) in less than 10 yrs but arsenate was retarded considerably due to surface reactions and has entered a groundwater well 850 m down the flow path in accordance to prediction by the 1D model, which further predicted a complete breakthrough of arsenate in the year 2100 while arsenite will be retained for about 1000 yrs.

Published
2009

22. A Call for Standards in the CO2 Value Chain

Author

Randi Neerup, Isaac A. Løge, Kári Helgason, Sandra Ó. Snæbjörnsdóttir, Bergur Sigfússon, Johan B. Svendsen, Nils T. Rosted, Peter Blinksbjerg, Jannik Kappel, Ragni Rørtveit, Szczepan Polak, Nik Felbab, Rasmus Holmer, Ajay Arora, Jimmy Andersen, Bogi B. Jensen, Sebastian N. B. Villadsen, Georgios M. Kontogeorgis, and Philip L. Fosbøl

Subjects
Environmental Chemistry, General Chemistry
Published
2022
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24. Demographic reconstruction from ancient DNA supports rapid extinction of the great auk

Author

Jessica E Thomas, Gary R Carvalho, James Haile, Nicolas J Rawlence, Michael D Martin, Simon YW Ho, Arnór Þ Sigfússon, Vigfús A Jósefsson, Morten Frederiksen, Jannie F Linnebjerg, Jose A Samaniego Castruita, Jonas Niemann, Mikkel-Holger S Sinding, Marcela Sandoval-Velasco, André ER Soares, Robert Lacy, Christina Barilaro, Juila Best, Dirk Brandis, Chiara Cavallo, Mikelo Elorza, Kimball L Garrett, Maaike Groot, Friederike Johansson, Jan T Lifjeld, Göran Nilson, Dale Serjeanston, Paul Sweet, Errol Fuller, Anne Karin Hufthammer, Morten Meldgaard, Jon Fjeldså, Beth Shapiro, Michael Hofreiter, John R Stewart, M Thomas P Gilbert, and Michael Knapp

Subjects
seabird exploitation, 19th century extinction, paleogenetics, hunting, ancient DNA, Medicine, Science, Biology (General), QH301-705.5
Abstract

The great auk was once abundant and distributed across the North Atlantic. It is now extinct, having been heavily exploited for its eggs, meat, and feathers. We investigated the impact of human hunting on its demise by integrating genetic data, GPS-based ocean current data, and analyses of population viability. We sequenced complete mitochondrial genomes of 41 individuals from across the species’ geographic range and reconstructed population structure and population dynamics throughout the Holocene. Taken together, our data do not provide any evidence that great auks were at risk of extinction prior to the onset of intensive human hunting in the early 16th century. In addition, our population viability analyses reveal that even if the great auk had not been under threat by environmental change, human hunting alone could have been sufficient to cause its extinction. Our results emphasise the vulnerability of even abundant and widespread species to intense and localised exploitation.

Published
2019
Full Text
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26. Rapid carbon mineralization for permanent disposal of anthropogenic carbon dioxide emissions

Author

Matter, Juerg M., Stute, Martin, Snæbjörnsdottir, Sandra Ó., Oelkers, Eric H., Gislason, Sigurdur R., Aradottir, Edda S., Sigfusson, Bergur, Gunnarsson, Ingvi, Sigurdardottir, Holmfridur, Gunnlaugsson, Einar, Axelsson, Gudni, Alfredsson, Helgi A., Wolff-Boenisch, Domenik, Mesfin, Kiflom, de la Reguera Taya, Diana Fernandez, Hall, Jennifer, Dideriksen, Knud, and Broecker, Wallace S.

Published
2016

29. Neonatal Lung Diseases

Author

Thorkelsson, Thordur, Sigfusson, Gunnlaugur, Wheeler, Derek S., editor, Wong, Hector R., editor, and Shanley, Thomas P., editor

Published
2014
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30. Studies of pre-breeding Fulmars (Fulmarus glacialis), their recruitment to breeding populations and intermittent breeding

Author

Sigfússon, Arnór Þórir

Subjects
590, Zoology
Abstract

The aim of the study was to attempt to identify prebreeding Fulmars and study their behaviour and look at their recruitment and intermittent breeding in general. Over 300 unringed Fulmars of unknown breeding status were caught and ringed during the study but it was not possible to positively identify a prebreeder from breeders. By looking at attendance at colonies throughout the year at confirmed nest-sites and potential nest-sites it was concluded that non-breeding birds were present throughout the prebreeding period although confirmed nest-sites were occupied more often and for longer. Also by looking at individually marked birds and comparing Fulmars of unknown breeding status with birds known to have bred, it was concluded that the latter category arrived earlier in the year in general. Fulmars not known to have bred before were more mobile within the colonies than breeding birds but little was established about dispersal to other colonies except one bird of unknown breeding status ringed on Eynhallow, Orkney, which was recovered at a colony in the Faeroes. The number of unringed Fulmars associated with Eynhallow but not breeding there was estimated about 1400-3100 birds. Intermittent breeding of Fulmars was found to fluctuate considerably between years as did index of recruitment and these two were negatively correlated. On average 28-29&'37 of fulmars which have bred before do not breed each year and that proportion correlated negatively with proportion of eggs hatching. Gaps in the breeding history lasting more than one year were often followed by a change in mate and/or nest-site. An attempt was made to experimentally prevent ten established pairs from breeding by blocking their sites. Time of loss of site was found to be important and the effects of losing the site could last more than one breeding season.

Published
1990

33. Carbon Fixation using Seawater for Sustainable Large-Scale Carbon Capture and Storage—Using stable isotopes for quantification

Author

Phillips, Elizabeth, primary, Voigt, Martin, additional, Bradbury, Harold, additional, Knapp, William J., additional, Turchyn, Alexandra (Sasha), additional, Tipper, Edward, additional, Snæbjörnsdóttir, Sandra, additional, Sigfússon, Bergur, additional, Clark, Deirdre, additional, Oelkers, Eric, additional, and Gislason, Sigurdur, additional

Published
2023
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34. A Call for Standards in the CO2 Value Chain

Author

Neerup, Randi, primary, Løge, Isaac A., additional, Helgason, Kári, additional, Snæbjörnsdóttir, Sandra Ó., additional, Sigfússon, Bergur, additional, Svendsen, Johan B., additional, Rosted, Nils T., additional, Blinksbjerg, Peter, additional, Kappel, Jannik, additional, Rørtveit, Ragni, additional, Polak, Szczepan, additional, Felbab, Nik, additional, Holmer, Rasmus, additional, Arora, Ajay, additional, Andersen, Jimmy, additional, Jensen, Bogi B., additional, Villadsen, Sebastian N. B., additional, Kontogeorgis, Georgios M., additional, and Fosbøl, Philip L., additional

Published
2022
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39. Rapid solubility and mineral storage of CO2 in basalt

Author

Gislason, Sigurdur R., Broecker, W.S., Gunnlaugsson, E., Snæbjörnsdóttir, S., Mesfin, K.G., Alfredsson, H.A., Aradottir, E.S., Sigfusson, B., Gunnarsson, I., Stute, M., Matter, J.M., Arnarson, M.Th., Galeczka, I.M., Gudbrandsson, S., Stockman, G., Boenisch, D. Wolff, Stefansson, A., Ragnheidardottir, E., Flaathen, T., Gysi, A.P., Olssen, J., Didriksen, K., Stipp, S., Menez, B., and Oelkers, E.H.

Published
2014
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41. Probabilistic Evaluation of Susceptibility to Fluid Injection-Induced Seismicity Based on Statistics of Fracture Criticality

Author

Wenzhuo Cao, Sevket Durucan, Wu Cai, Ji-Quan Shi, Anna Korre, Thomas Ratouis, Vala Hjörleifsdóttir, Bergur Sigfússon, BEIS - Department for Business, Energy and Industrial Strategy, and Department for Business, Energy & Industrial Strategy

Subjects
0914 Resources Engineering and Extractive Metallurgy, Geology, Geological & Geomatics Engineering, Geotechnical Engineering and Engineering Geology, 0905 Civil Engineering, Civil and Structural Engineering
Abstract

Fault reactivation and associated microseismicity pose a potential threat to industrial processes involving fluid injection into the subsurface. In this research, fracture criticality, defined as the gradient of critical fluid pressure change to trigger seismicity (Δpc/h), is proposed as a novel reservoir depth-independent metric of fault slip susceptibility. Based on statistics of the fracture criticality, a probabilistic evaluation framework for susceptibility to injection-induced seismicity was developed by integrating seismic observations and hydrogeological modelling of fluid injection operations for faulted reservoirs. The proposed seismic susceptibility evaluation method considers the injection-driven fluid pressure increase, the variability of fracture criticality, and regional fracture density. Utilising this methodology, the probabilistic distribution of fracture criticality was obtained to evaluate the potential for injection-induced seismicity in both fault and off-fault zones at the Hellisheiði geothermal site, Iceland. It has been found that the fracture criticality within both fault and off-fault zones shows natural variability (mostly ranging between 0.001 and 2.0 bar/km), and that fault zones tend to be characterised by larger fracture criticality values than the off-faut zones. Fracture criticality values estimated within each zone roughly follow a Gaussian distribution. Fault zones around five geothermal fluid re-injection wells at the site were estimated to have relatively high probability of seismic event occurrence, and these regions experienced high levels of induced seismicity over the microseismic monitoring period. The seismotectonic state estimated for each zone is generally consistent with the forecasted susceptibility to seismicity based on statistics of fracture criticality.

Published
2022
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