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Journal articles on the topic 'Non polar Ice core'

Author: Grafiati

Published: 9 March 2023

Last updated: 31 July 2025

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1

Song, Jing. "Ice Core Methane Analytical Techniques, Chronology and Concentration History Changes: A Review." Sustainability 15, no. 12 (2023): 9346. http://dx.doi.org/10.3390/su15129346.

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Ice cores are invaluable in paleoclimate research, offering unique insights into the evolution of the natural environment, human activities, and Earth’s climate system. Methane (CH4) is a crucial greenhouse gas, second only to CO2 in its contribution to global warming, and is one of the primary anthropogenic greenhouse gases. Understanding historical CH4 concentration changes is essential for predicting future trends and informing climate change mitigation strategies. By analyzing gas components trapped in ice core bubbles, we can directly examine the composition of ancient atmospheres. Howeve

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2

Legrand, Michel. "Ice–core records of atmospheric sulphur." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 352, no. 1350 (1997): 241–50. http://dx.doi.org/10.1098/rstb.1997.0019.

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Sulphate and methanesulphonate (MSA), the two major sulphur species trapped in polar ice, have been extensivelyh studied in Antarctic and Greenland ice cores spanning the last centuries, as well as the entire last climatic cycle. Data from the cores are used to investigate the past contribution of volcanic and biogenic emissions to the natural sulphur budget in high latitude regions of both Hemispheres. Sulphate concentrations in polar ice very often increased during one or two years after large volcanic eruptions. Sulphate records show that fossil fuel combustion has enhanced sulphate concent

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3

Shoji, Hitoshi, Atau Mitani, Kohji Horita, and Chester C. Langway. "Crystal growth rates in polar firn." Annals of Glaciology 18 (1993): 208–10. http://dx.doi.org/10.3189/s0260305500011526.

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Continuous crystal-size measurements made on the G6 Antarctic ice core (100m deep) show enhanced growth rates above a depth of 30 m (Zone 1) and in the interval between 70 and 80 m (Zone 2). Crystal growth in Zone 1 most probably takes place by a process of sublimation and condensation. The higher growth rate in Zone 2 is most probably related to the pore close-off transformation process in which a non-uniform strain field is created to form air bubbles by plastic deformation and “cannibalization” of individual ice crystals.

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Shoji, Hitoshi, Atau Mitani, Kohji Horita, and Chester C. Langway. "Crystal growth rates in polar firn." Annals of Glaciology 18 (1993): 208–10. http://dx.doi.org/10.1017/s0260305500011526.

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Continuous crystal-size measurements made on the G6 Antarctic ice core (100m deep) show enhanced growth rates above a depth of 30 m (Zone 1) and in the interval between 70 and 80 m (Zone 2). Crystal growth in Zone 1 most probably takes place by a process of sublimation and condensation. The higher growth rate in Zone 2 is most probably related to the pore close-off transformation process in which a non-uniform strain field is created to form air bubbles by plastic deformation and “cannibalization” of individual ice crystals.

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5

Tornow, Carmen, Ekkehard Kührt, Stefan Kupper, and Uwe Motschmann. "Interaction between gas and ice phase in the three periods of the solar nebula." Proceedings of the International Astronomical Union 5, S263 (2009): 50–54. http://dx.doi.org/10.1017/s1743921310001493.

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AbstractWe simulate the chemical processes in the three evolution periods of the solar nebula, which are (i) the quasi-stationary prestellar cloud core, (ii) the gravitationally collapsing protostellar core, and (iii) the evolving gas-dust disk. Our purpose is to identify chemical parameters which reflect special aspects of the interactions between the gas and ice phase in the different periods, e.g. isotopic or molecular ratios. In this study we derive the D/H and 15N/14N ratio of selected compounds as well as the CO2/H2O ratio to measure the fraction of non-polar to polar ice in the grain ma

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6

Kerch, Johanna, Anja Diez, Ilka Weikusat, and Olaf Eisen. "Deriving micro- to macro-scale seismic velocities from ice-core <i>c</i> axis orientations." Cryosphere 12, no. 5 (2018): 1715–34. http://dx.doi.org/10.5194/tc-12-1715-2018.

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Abstract. One of the great challenges in glaciology is the ability to estimate the bulk ice anisotropy in ice sheets and glaciers, which is needed to improve our understanding of ice-sheet dynamics. We investigate the effect of crystal anisotropy on seismic velocities in glacier ice and revisit the framework which is based on fabric eigenvalues to derive approximate seismic velocities by exploiting the assumed symmetry. In contrast to previous studies, we calculate the seismic velocities using the exact c axis angles describing the orientations of the crystal ensemble in an ice-core sample. We

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Weikusat, Ilka, Ernst-Jan N. Kuiper, Gill M. Pennock, Sepp Kipfstuhl, and Martyn R. Drury. "EBSD analysis of subgrain boundaries and dislocation slip systems in Antarctic and Greenland ice." Solid Earth 8, no. 5 (2017): 883–98. http://dx.doi.org/10.5194/se-8-883-2017.

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Abstract. Ice has a very high plastic anisotropy with easy dislocation glide on basal planes, while glide on non-basal planes is much harder. Basal glide involves dislocations with the Burgers vector b = 〈a〉, while glide on non-basal planes can involve dislocations with b = 〈a〉, b = [c], and b = 〈c + a〉. During the natural ductile flow of polar ice sheets, most of the deformation is expected to occur by basal slip accommodated by other processes, including non-basal slip and grain boundary processes. However, the importance of different accommodating processes is controversial. The recent appl

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8

NG, Felix, and T. H. Jacka. "A model of crystal-size evolution in polar ice masses." Journal of Glaciology 60, no. 221 (2014): 463–77. http://dx.doi.org/10.3189/2014jog13j173.

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AbstractIn the deep ice cores drilled at the GRIP, NGRIP and GISP2 sites in Greenland and at Byrd Station and the summit of Law Dome in Antarctica, the mean crystal size increases with depth in the shallow subsurface and reaches steady values at intermediate depth. This behaviour has been attributed to the competition between grain-boundary migration driven crystal growth and crystal polygonization, but the effects of changing crystal dislocation density and non-equiaxed crystal shape in this competition are uncertain. We study these effects with a simple model. It describes how the mean heigh

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9

Shen, Liang, Yongqin Liu, Tandong Yao, et al. "Dyadobacter tibetensis sp. nov., isolated from glacial ice core." International Journal of Systematic and Evolutionary Microbiology 63, Pt_10 (2013): 3636–39. http://dx.doi.org/10.1099/ijs.0.050328-0.

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A Gram-stain-negative, rod-shaped, aerobic, non-motile bacterium, designated Y620-1T, was isolated from a glacier on the Tibetan Plateau, China. The 16S rRNA gene sequence of the novel isolate shared 93.6–95.1 % similarity with type strains of species of the genus Dyadobacter . The major fatty acids of strain Y620-1T were summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), iso-C15 : 0, C16 : 1ω5c and iso-C17 : 0 3-OH. The predominant isoprenoid quinone and polar lipid were MK-7 and phosphatidylethanolamine (PE), respectively. The DNA G+C content was 44.4±0.3 mol% (T m). Flexirubin-type pigm

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10

Elsässer, C., D. Wagenbach, I. Levin, et al. "Simulating ice core <sup>10</sup>Be on the glacial–interglacial timescale." Climate of the Past 11, no. 2 (2015): 115–33. http://dx.doi.org/10.5194/cp-11-115-2015.

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Abstract. 10Be ice core measurements are an important tool for paleoclimate research, e.g., allowing for the reconstruction of past solar activity or changes in the geomagnetic dipole field. However, especially on multi-millennial timescales, the share of production and climate-induced variations of respective 10Be ice core records is still up for debate. Here we present the first quantitative climatological model of the 10Be ice concentration up to the glacial–interglacial timescale. The model approach is composed of (i) a coarse resolution global atmospheric transport model and (ii) a local

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Schwikowski, Margit, Sabina Brütsch, Gino Casassa та Andrés Rivera. "A potential high-elevation ice-core site at Hielo Patagόnico Sur". Annals of Glaciology 43 (2006): 8–13. http://dx.doi.org/10.3189/172756406781812014.

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AbstractThe Patagonia icefields constitute a unique location in the Southern Hemisphere for obtaining non-polar paleo-records from ice cores south of 45°S. Nevertheless, no ice-core record with meaningful paleoclimate information has yet been obtained from Patagonia. This deficiency is due to extremely harsh field conditions, and to the fact that the main plateaus of both Hielo Patagónico Norte (HPN; northern Patagonia icefield) and Hielo Patagónico Sur (HPS; southern Patagonia icefield) are strongly affected by meltwater percolation. In order to explore the suitability of high-elevation glaci

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Elsässer, C., D. Wagenbach, I. Levin, et al. "Simulating ice core <sup>10</sup>Be on the glacial–interglacial timescale." Climate of the Past Discussions 10, no. 1 (2014): 761–808. http://dx.doi.org/10.5194/cpd-10-761-2014.

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Abstract. 10Be ice core measurements are an important tool for paleoclimate research, e.g. allowing for the reconstruction of past solar activity or variation in the natural 14C production rate. However, especially on multi-millennial timescales, the share of production and climate induced variations of respective 10Be ice core records is still up to debate. Here we present the first quantitative climatological model of the 10Be ice concentration up to the glacial–interglacial timescale. The model approach is composed of (i) a coarse resolution global atmospheric transport model and (ii) a loc

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13

Sigl, M., T. M. Jenk, T. Kellerhals, et al. "Towards radiocarbon dating of ice cores." Journal of Glaciology 55, no. 194 (2009): 985–96. http://dx.doi.org/10.3189/002214309790794922.

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AbstractA recently developed dating method for glacier ice, based on the analysis of radiocarbon in carbonaceous aerosol particles, is thoroughly investigated. We discuss the potential of this method to achieve a reliable dating using examples from a mid- and a low-latitude ice core. Two series of samples from Colle Gnifetti (4450 m a.s.l., Swiss Alps) and Nevado Illimani (6300 m a.s.l., Bolivian Andes) demonstrate that the 14C ages deduced from the water-insoluble organic carbon fraction represent the age of the ice. Sample sizes ranged between 7 and 100 μg carbon. For validation we compare o

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Konrad, Hannes, Pascal Bohleber, Dietmar Wagenbach, Christian Vincent, and Olaf Eisen. "Determining the age distribution of Colle Gnifetti, Monte Rosa, Swiss Alps, by combining ice cores, ground-penetrating radar and a simple flow model." Journal of Glaciology 59, no. 213 (2013): 179–89. http://dx.doi.org/10.3189/2013jog12j072.

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AbstractIce cores from cold Alpine glaciers may provide unique paleoclimate information from non-polar latitudes. We explore the three-dimensional internal age distribution of the small cold glacier saddle (Colle Gnifetti, Monte Rosa, Italy/Switzerland) to compare the age/depth relations from four local deep ice cores. Tracking isochronous reflection horizons detected by ground-penetrating radar (GPR) among the core locations reveals consistent dating up to 80 years BP. This approach is confined to recent ages, due to the lack of clear reflections below the firn/ice transition. We attempt to o

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15

Wolff, Eric, and Renato Spahni. "Methane and nitrous oxide in the ice core record." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 365, no. 1856 (2007): 1775–92. http://dx.doi.org/10.1098/rsta.2007.2044.

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Polar ice cores contain, in trapped air bubbles, an archive of the concentrations of stable atmospheric gases. Of the major non-CO 2 greenhouse gases, methane is measured quite routinely, while nitrous oxide is more challenging, with some artefacts occurring in the ice and so far limited interpretation. In the recent past, the ice cores provide the only direct measure of the changes that have occurred during the industrial period; they show that the current concentration of methane in the atmosphere is far outside the range experienced in the last 650 000 years; nitrous oxide is also elevated

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16

Winton, V. Holly L., Robert Mulvaney, Joel Savarino, Kyle R. Clem, and Markus M. Frey. "Drivers of late Holocene ice core chemistry in Dronning Maud Land: the context for the ISOL-ICE project." Climate of the Past 20, no. 5 (2024): 1213–32. http://dx.doi.org/10.5194/cp-20-1213-2024.

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Abstract. Within the framework of the Isotopic Constraints on Past Ozone Layer in Polar Ice (ISOL-ICE) project, we present initial ice core results from the new ISOL-ICE ice core covering the last millennium from high-elevation Dronning Maud Land (DML) and discuss the implications for interpreting the stable isotopic composition of nitrogen in ice core nitrate (δ15N(NO3-)) as a surface ultra-violet radiation (UV) and total column ozone (TCO) proxy. In the quest to derive TCO using δ15N(NO3-), an understanding of past snow accumulation changes, as well as aerosol source regions and present-day

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17

Chubarenko, Irina. "Physical processes behind interactions of microplastic particles with natural ice." Environmental Research Communications 4, no. 1 (2022): 012001. http://dx.doi.org/10.1088/2515-7620/ac49a8.

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Abstract Microplastic particles (MPs, <5 mm) are found in marine ice in larger quantities than in seawater, however, the distribution pattern within the ice cores is not consistent. To get insights into the most general physical processes behind interactions of ice and plastic particles in cool natural environments, information from academic and applied research is integrated and verified against available field observations. Non-polar molecules of common-market plastics are hydrophobic, so MPs are weak ice nucleators, are repelled from water and ice, and concentrate within air bubbles and

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18

Curran, Mark A. J., Tas D. Van Ommen, and Vin Morgan. "Seasonal characteristics of the major ions in the high-accumulation Dome Summit South ice core, Law Dome, Antarctica." Annals of Glaciology 27 (1998): 385–90. http://dx.doi.org/10.3189/1998aog27-1-385-390.

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Seasonal cycles of the chemical species Na+, Κ+ , Mg2+, Ca2+, CH3SO3 (MSA) Cl− NO3 − and NO3 − in the Dome Summit South (DSS) ice core from Law Dome were measured for a number of epochs (AD 1809-15, 1821-31 1980-92) span-nine a total of 28 years. These preliminary trace-chemical patterns show that the DSS site is mainly affected by marine air. The main features found in the seasonal pattern of sea-salt concentrations (e.g. Na+, Cl− and Mg2+) were a winter peak and a summer minimum. The variations in sea salts are believed to reflect aerosol production and transport due to the level of stormine

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19

Curran, Mark A. J., Tas D. Van Ommen, and Vin Morgan. "Seasonal characteristics of the major ions in the high-accumulation Dome Summit South ice core, Law Dome, Antarctica." Annals of Glaciology 27 (1998): 385–90. http://dx.doi.org/10.1017/s0260305500017778.

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Seasonal cycles of the chemical species Na+, Κ+ , Mg2+, Ca2+, CH3SO3 (MSA) Cl− NO3 − and NO3 − in the Dome Summit South (DSS) ice core from Law Dome were measured for a number of epochs (AD 1809-15, 1821-31 1980-92) span-nine a total of 28 years. These preliminary trace-chemical patterns show that the DSS site is mainly affected by marine air. The main features found in the seasonal pattern of sea-salt concentrations (e.g. Na+, Cl− and Mg2+) were a winter peak and a summer minimum. The variations in sea salts are believed to reflect aerosol production and transport due to the level of stormine

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20

Gibson, John A. E., Kristina S. Paterson, Camille A. White, and Kerrie M. Swadling. "Evidence for the continued existence of Abraxas Lake, Vestfold Hills, East Antarctica during the Last Glacial Maximum." Antarctic Science 21, no. 3 (2009): 269–78. http://dx.doi.org/10.1017/s0954102009001801.

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AbstractEvidence is provided from a sediment core from saline Abraxas Lake, Vestfold Hills, that indicates that the lake existed through the Last Glacial Maximum. It can therefore be concluded that at least part of the Vestfold Hills also remained ice-free through the Last Glacial Maximum, or at most was covered by a thin, non-erosive cold-based ice sheet. The evidence for the continued existence of Abraxas Lake includes a 14C date that significantly predates the Last Glacial Maximum (though this cannot be considered direct proof of the existence of the lake prior to the Last Glacial Maximum);

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21

Gautier, E., J. Savarino, J. Erbland, A. Lanciki, and P. Possenti. "Variability of sulfate signal in ice core records based on five replicate cores." Climate of the Past 12, no. 1 (2016): 103–13. http://dx.doi.org/10.5194/cp-12-103-2016.

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Abstract. Current volcanic reconstructions based on ice core analysis have significantly improved over the past few decades by incorporating multiple-core analyses with a high temporal resolution from different parts of the polar regions into a composite common volcanic eruption record. Regional patterns of volcanic deposition are based on composite records, built from cores taken at both poles. However, in many cases only a single record at a given site is used for these reconstructions. This assumes that transport and regional meteorological patterns are the only source of the dispersion of

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Gautier, E., J. Savarino, J. Erbland, A. Lanciki, and P. Possenti. "Variability of sulfate signal in ice-core records based on five replicate cores." Climate of the Past Discussions 11, no. 4 (2015): 3973–4002. http://dx.doi.org/10.5194/cpd-11-3973-2015.

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Abstract. Current volcanic reconstructions based on ice core analysis have significantly improved over the last decades. Relying on limited and disparate sulfate profiles at first, they have progressively incorporated multi cores analysis with high temporal resolution from different parts of the Polar Regions. Regional patterns of volcanic deposition flux are now based on composite records, built from several cores taken at both poles. However, it is worth mentioning that most of the time only a single record at a given site is used for such reconstructions. This implicitly assumes that transp

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23

Jónsdóttir, Ingibjörg Rósa, Sædís Ólafsdóttir, and Áslaug Geirsdóttir. "Marine climate variability from Arnarfjörður, NW Iceland, during the Medieval Warm period and early/middle Little Ice Age." Jökull 65, no. 1 (2015): 73–87. http://dx.doi.org/10.33799/jokull2015.65.073.

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A high-resolution sedimentary record from the subarctic fjord Arnarfjörður in northwestern Iceland provides information on local changes in sea ice cover and a regional oceanographic climatic signal reflecting changes in the position of the Polar Front that separates the North Atlantic Current and the East Greenland Current. The 520 cm long sediment core spans approximately 2000 years and thus offers a multi-decadal time resolution during the Medieval Warm Period (MWP) and the early to middle part of the Little Ice Age (LIA). Approximately 150 years from the top of the core were lost during co

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Siggaard-Andersen, Marie-Louise, Jørgen Peder Steffensen, and Hubertus Fischer. "Lithium in Greenland ice cores measured by ion chromatography." Annals of Glaciology 35 (2002): 243–49. http://dx.doi.org/10.3189/172756402781816483.

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AbstractIon chromatography (IC) is a widely used technique for analyzing ice cores for ions like Na+, NH4+, K+, Mg2+, Ca2+, F–, MSA–, Cl–, NO2– and SO42– that are present in polar ice cores at ppb level. By using sample preconcentration and an optimized separation technique, we have been able to detect Li+ in ice-core samples in concentrations as low as 0.0001 μeq kg–1 or 0.7 ppt by IC. During routine analysis of ions in ice cores, the lithium content has been evaluated and recorded. the IC technique used in these measurements and some exemplary IC data from the Greenland Icecore Project (GRIP

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Witrant, E., P. Martinerie, C. Hogan, et al. "A new multi-gas constrained model of trace gas non-homogeneous transport in firn: evaluation and behaviour at eleven polar sites." Atmospheric Chemistry and Physics 12, no. 23 (2012): 11465–83. http://dx.doi.org/10.5194/acp-12-11465-2012.

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Abstract. Insoluble trace gases are trapped in polar ice at the firn-ice transition, at approximately 50 to 100 m below the surface, depending primarily on the site temperature and snow accumulation. Models of trace gas transport in polar firn are used to relate firn air and ice core records of trace gases to their atmospheric history. We propose a new model based on the following contributions. First, the firn air transport model is revised in a poromechanics framework with emphasis on the non-homogeneous properties and the treatment of gravitational settling. We then derive a nonlinear least

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Kobashi, T., T. Ikeda-Fukazawa, M. Suwa, et al. "Post bubble-closeoff fractionation of gases in polar firn and ice cores: effects of accumulation rate on permeation through overloading pressure." Atmospheric Chemistry and Physics Discussions 15, no. 11 (2015): 15711–53. http://dx.doi.org/10.5194/acpd-15-15711-2015.

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Abstract. Gases in ice cores are invaluable archives of past environmental changes (e.g., the past atmosphere). However, gas fractionation processes after bubble closure in the firn are poorly understood, although increasing evidence indicates preferential leakages of smaller molecules (e.g., neon, oxygen, and argon) from the closed bubbles through ice crystals. These fractionation processes are believed to be responsible for the observed millennial δO2/N2 variations in ice cores, linking ice core chronologies with orbital parameters. Herein, we found that δAr/N2 at decadal resolution on the g

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27

Pickard, Heidi M., Alison S. Criscitiello, Christine Spencer, et al. "Continuous non-marine inputs of per- and polyfluoroalkyl substances to the High Arctic: a multi-decadal temporal record." Atmospheric Chemistry and Physics 18, no. 7 (2018): 5045–58. http://dx.doi.org/10.5194/acp-18-5045-2018.

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Abstract. Perfluoroalkyl acids (PFAAs) are persistent, in some cases, bioaccumulative compounds found ubiquitously within the environment. They can be formed from the atmospheric oxidation of volatile precursor compounds and undergo long-range transport (LRT) through the atmosphere and ocean to remote locations. Ice caps preserve a temporal record of PFAA deposition making them useful in studying the atmospheric trends in LRT of PFAAs in polar or mountainous regions, as well as in understanding major pollutant sources and production changes over time. A 15 m ice core representing 38 years of d

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Rhodes, Rachael H., Xavier Faïn, Edward J. Brook, et al. "Local artifacts in ice core methane records caused by layered bubble trapping and in situ production: a multi-site investigation." Climate of the Past 12, no. 4 (2016): 1061–77. http://dx.doi.org/10.5194/cp-12-1061-2016.

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Abstract. Advances in trace gas analysis allow localised, non-atmospheric features to be resolved in ice cores, superimposed on the coherent atmospheric signal. These high-frequency signals could not have survived the low-pass filter effect that gas diffusion in the firn exerts on the atmospheric history and therefore do not result from changes in the atmospheric composition at the ice sheet surface. Using continuous methane (CH4) records obtained from five polar ice cores, we characterise these non-atmospheric signals and explore their origin. Isolated samples, enriched in CH4 in the Tunu13 (

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Witrant, E., P. Martinerie, C. Hogan, et al. "A new multi-gas constrained model of trace gas non-homogeneous transport in firn: evaluation and behavior at eleven polar sites." Atmospheric Chemistry and Physics Discussions 11, no. 8 (2011): 23029–80. http://dx.doi.org/10.5194/acpd-11-23029-2011.

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Abstract. Insoluble trace gases are trapped in polar ice at the firn-ice transition, at approximately 50 to 100 m below the surface, depending primarily on the site temperature and snow accumulation. Due to the different time scales for snow accumulation versus diffusion of gases through the snowpack, age differences between gases and the ice in which they are "trapped" can be large; e.g. several thousand years in central Antarctica (a low snow accumulation area). Models of trace gas diffusion in polar firn are used to relate firn air and ice core records of trace gases to their atmospheric hi

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Kobashi, T., T. Ikeda-Fukazawa, M. Suwa, et al. "Post-bubble close-off fractionation of gases in polar firn and ice cores: effects of accumulation rate on permeation through overloading pressure." Atmospheric Chemistry and Physics 15, no. 24 (2015): 13895–914. http://dx.doi.org/10.5194/acp-15-13895-2015.

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Abstract. Gases in ice cores are invaluable archives of past environmental changes (e.g., the past atmosphere). However, gas fractionation processes after bubble closure in the firn are poorly understood, although increasing evidence indicates preferential leakages of smaller molecules (e.g., neon, oxygen, and argon) from the closed bubbles through the ice matrix. These fractionation processes are believed to be responsible for the observed millennial δO2/N2 variations in ice cores, linking ice core chronologies with orbital parameters. In this study, we investigated high-resolution δAr/N2 of

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31

Llorens, Maria-Gema, Albert Griera, Paul D. Bons, et al. "Can changes in deformation regimes be inferred from crystallographic preferred orientations in polar ice?" Cryosphere 16, no. 5 (2022): 2009–24. http://dx.doi.org/10.5194/tc-16-2009-2022.

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Abstract. Creep due to ice flow is generally thought to be the main cause for the formation of crystallographic preferred orientations (CPOs) in polycrystalline anisotropic ice. However, linking the development of CPOs to the ice flow history requires a proper understanding of the ice aggregate's microstructural response to flow transitions. In this contribution the influence of ice deformation history on the CPO development is investigated by means of full-field numerical simulations at the microscale. We simulate the CPO evolution of polycrystalline ice under combinations of two consecutive

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Ning, Chenhui, Shiming Xu, Yan Zhang, Xuantong Wang, Zhihao Fan, and Jiping Liu. "Lagrangian tracking of sea ice in Community Ice CodE (CICE; version 5)." Geoscientific Model Development 17, no. 17 (2024): 6847–66. http://dx.doi.org/10.5194/gmd-17-6847-2024.

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Abstract. Sea ice models are essential tools for simulating the thermodynamic and dynamic processes of sea ice and the coupling with the polar atmosphere and ocean. Popular models such as the Community Ice CodE (CICE) are usually based on non-moving, locally orthogonal Eulerian grids. However, the various in situ observations, such as those from ice-tethered buoys and drift stations, are subjected to sea ice drift and are, hence, by nature Lagrangian. Furthermore, the statistical analysis of sea ice kinematics requires the Lagrangian perspective. As a result, the offline sea ice tracking with

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Börger, Lara, Michael Schindelegger, Mengnan Zhao, et al. "Chaotic oceanic excitation of low-frequency polar motion variability." Earth System Dynamics 16, no. 1 (2025): 75–90. https://doi.org/10.5194/esd-16-75-2025.

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Abstract. Studies of Earth rotation variations generally assume that changes in non-tidal oceanic angular momentum (OAM) manifest the ocean's direct response to atmospheric forces. However, fluctuations in OAM may also arise from chaotic intrinsic ocean processes that originate in local nonlinear (e.g., mesoscale) dynamics and can map into motions and mass variations at basin scales. To examine whether such random mass redistributions effectively excite polar motion, we compute monthly OAM anomalies from a 50-member ensemble of eddy-permitting global ocean/sea ice simulations that sample intri

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Langway, C. C., and K. Goto-Azuma. "Temporal Variations in the Deep Ice-Core Chemistry Record from Dye 3, Greenland (Abstract)." Annals of Glaciology 10 (1988): 209. http://dx.doi.org/10.3189/s0260305500004559.

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Measurements of the chemical constituents in polar-snow deposits translate into chronological records representing a history of atmospheric composition for the periods involved. The 2037 m deep continuous and undisturbed ice core recovered at Dye 3, Greenland between 1979 and 1981 contains a temporal record of sequential snow deposits for the past 9 × 104 a B.P. (Dansgaard and others 1985). The upper 90 m of the deep core were unsuitable for chemistry studies, but stratigraphic continuity with present-day accumulation was obtained by hand-excavating a 5.4 m deep pit and augering two shallow co

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Langway, C. C., and K. Goto-Azuma. "Temporal Variations in the Deep Ice-Core Chemistry Record from Dye 3, Greenland (Abstract)." Annals of Glaciology 10 (1988): 209. http://dx.doi.org/10.1017/s0260305500004559.

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Measurements of the chemical constituents in polar-snow deposits translate into chronological records representing a history of atmospheric composition for the periods involved. The 2037 m deep continuous and undisturbed ice core recovered at Dye 3, Greenland between 1979 and 1981 contains a temporal record of sequential snow deposits for the past 9 × 104 a B.P. (Dansgaard and others 1985). The upper 90 m of the deep core were unsuitable for chemistry studies, but stratigraphic continuity with present-day accumulation was obtained by hand-excavating a 5.4 m deep pit and augering two shallow co

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Upadhyaya, Kalpana, Venkatesh Gude, Golam Mohiuddin, and Rao V. S. Nandiraju. "A new family of four-ring bent-core nematic liquid crystals with highly polar transverse and end groups." Beilstein Journal of Organic Chemistry 9 (January 7, 2013): 26–35. http://dx.doi.org/10.3762/bjoc.9.4.

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Non-symmetrically substituted four-ring achiral bent-core compounds with polar substituents, i.e.., chloro in the bent or transverse direction in the central core and cyano in the lateral direction at one terminal end of the molecule, are designed and synthesized. These molecules possess an alkoxy chain attached at only one end of the bent-core molecule. The molecular structure characterization is consistent with data from elemental and spectroscopic analysis. The materials thermal behaviour and phase characterization have been investigated by differential scanning calorimetry and polarizing m

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Erhardt, Tobias, Matthias Bigler, Urs Federer, et al. "High-resolution aerosol concentration data from the Greenland NorthGRIP and NEEM deep ice cores." Earth System Science Data 14, no. 3 (2022): 1215–31. http://dx.doi.org/10.5194/essd-14-1215-2022.

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Abstract. Records of chemical impurities from ice cores enable us to reconstruct the past deposition of aerosols onto polar ice sheets and alpine glaciers. Through this they allow us to gain insight into changes of the source, transport and deposition processes that ultimately determine the deposition flux at the coring location. However, the low concentrations of the aerosol species in the ice and the resulting high risk of contamination pose a formidable analytical challenge, especially if long, continuous and highly resolved records are needed. Continuous flow analysis, CFA, the continuous

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Festi, Daniela, Luca Carturan, Werner Kofler, et al. "Linking pollen deposition and snow accumulation on the Alto dell'Ortles glacier (South Tyrol, Italy) for sub-seasonal dating of a firn temperate core." Cryosphere 11, no. 2 (2017): 937–48. http://dx.doi.org/10.5194/tc-11-937-2017.

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Abstract. Dating of ice cores from temperate non-polar glaciers is challenging and often problematic. However, a proper timescale is essential for a correct interpretation of the proxies measured in the cores. Here, we introduce a new method developed to obtain a sub-seasonal timescale relying on statistically measured similarities between pollen spectra obtained from core samples and daily airborne pollen monitoring samples collected in the same area. This approach was developed on a 10 m core retrieved from the temperate-firn portion of Alto dell'Ortles glacier (Eastern Italian Alps), for wh

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Heaton, Timothy J., Peter Köhler, Martin Butzin, et al. "Marine20—The Marine Radiocarbon Age Calibration Curve (0–55,000 cal BP)." Radiocarbon 62, no. 4 (2020): 779–820. http://dx.doi.org/10.1017/rdc.2020.68.

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ABSTRACTThe concentration of radiocarbon (14C) differs between ocean and atmosphere. Radiocarbon determinations from samples which obtained their 14C in the marine environment therefore need a marine-specific calibration curve and cannot be calibrated directly against the atmospheric-based IntCal20 curve. This paper presents Marine20, an update to the internationally agreed marine radiocarbon age calibration curve that provides a non-polar global-average marine record of radiocarbon from 0–55 cal kBP and serves as a baseline for regional oceanic variation. Marine20 is intended for calibration

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Winton, V. Holly L., Alison Ming, Nicolas Caillon, et al. "Deposition, recycling, and archival of nitrate stable isotopes between the air–snow interface: comparison between Dronning Maud Land and Dome C, Antarctica." Atmospheric Chemistry and Physics 20, no. 9 (2020): 5861–85. http://dx.doi.org/10.5194/acp-20-5861-2020.

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Abstract. The nitrogen stable isotopic composition in nitrate (δ15N-NO3-) measured in ice cores from low-snow-accumulation regions in East Antarctica has the potential to provide constraints on past ultraviolet (UV) radiation and thereby total column ozone (TCO) due to the sensitivity of nitrate (NO3-) photolysis to UV radiation. However, understanding the transfer of reactive nitrogen at the air–snow interface in polar regions is paramount for the interpretation of ice core records of δ15N-NO3- and NO3- mass concentrations. As NO3- undergoes a number of post-depositional processes before it i

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Hide, Raymond. "Forecasting short-term changes in the Earth's rotation." Symposium - International Astronomical Union 128 (1988): 287–88. http://dx.doi.org/10.1017/s007418090011962x.

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Summary of PosterIt has long been appreciated that atmospheric motions must contribute to the excitation of fluctuations in the Earth's rotation (Munk and MacDonald 1960, Lambeck 1980, Rochester 1984) but the exploitation of modern meteorological data, collected largely to meet the demands of daily global weather forecasting, in the routine evaluation of angular momentum exchange between the atmosphere and the solid Earth was not initiated until comparatively recently (Hide et al. 1980). This procedure constitutes a necessary step towards the accurate separation of these features of the observ

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Paleari, Chiara I., Florian Mekhaldi, Tobias Erhardt, et al. "Evaluating the 11-year solar cycle and short-term ¹⁰Be deposition events with novel excess water samples from the East Greenland Ice-core Project (EGRIP)." Climate of the Past 19, no. 11 (2023): 2409–22. http://dx.doi.org/10.5194/cp-19-2409-2023.

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Abstract. 10Be is produced by the interaction between galactic cosmic rays (GCRs) and solar energetic particles (SEPs) with the Earth's atmospheric constituents. The flux of GCRs is modulated by the varying strength of the magnetic fields of the Earth and the Sun. Measurement of 10Be concentrations from polar ice cores is thus a valuable tool to reconstruct the variations in the geomagnetic field and solar activity levels. The interpretation of 10Be records is, however, complicated by non-production-related effects on the 10Be deposition rate caused by climate- or weather-induced variability.

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Golosov, V. N., B. R. Mavlyudov, S. V. Kharchenko, et al. "Sediment runoff formation in a small periglacial catchment on the King George (Vaterloo) island, Antarctica." Lomonosov Geography Journal 79, no. 4 (2024) (2024): 3–16. http://dx.doi.org/10.55959/msu0579-9414.5.79.4.1.

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Global climate change has most significantly affected the Polar Regions. The increase in air temperature has stimulated the melting of glaciers in the Arctic and Antarctic, which has contributed to changes in the formation of water and sediment runoff. However, there are very few quantitative estimates of the sediment redistribution in the periglacial catchments of the Polar Regions. Specific features of water and sediment runoff were studied within the catchment area of the Korabelnyj Stream located on the Fildes Peninsula in Antarctica near the Bellingshausen Ice Dome. The main aim of the st

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Münch, Thomas, and Thomas Laepple. "What climate signal is contained in decadal- to centennial-scale isotope variations from Antarctic ice cores?" Climate of the Past 14, no. 12 (2018): 2053–70. http://dx.doi.org/10.5194/cp-14-2053-2018.

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Abstract. Ice-core-based records of isotopic composition are a proxy for past temperatures and can thus provide information on polar climate variability over a large range of timescales. However, individual isotope records are affected by a multitude of processes that may mask the true temperature variability. The relative magnitude of climate and non-climate contributions is expected to vary as a function of timescale, and thus it is crucial to determine those temporal scales on which the actual signal dominates the noise. At present, there are no reliable estimates of this timescale dependen

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Jiang, Zhuang, Becky Alexander, Joel Savarino, and Lei Geng. "An inverse model to correct for the effects of post-depositional processing on ice-core nitrate and its isotopes: model framework and applications at Summit, Greenland, and Dome C, Antarctica." Atmospheric Chemistry and Physics 24, no. 8 (2024): 4895–914. http://dx.doi.org/10.5194/acp-24-4895-2024.

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Abstract. Comprehensive evaluation of the effects of post-depositional processing is a prerequisite for appropriately interpreting ice-core records of nitrate concentration and isotopes. In this study, we developed an inverse model that uses archived snow/ice-core nitrate signals to reconstruct primary nitrate flux (i.e., the deposition flux of nitrate to surface snow that originates from long-range transport or stratospheric input) and its isotopes (δ15N and Δ17O). The model was then applied to two polar sites, Summit, Greenland, and Dome C, Antarctica, using measured snowpack nitrate concent

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Uglietti, Chiara, Alexander Zapf, Theo Manuel Jenk, et al. "Radiocarbon dating of glacier ice: overview, optimisation, validation and potential." Cryosphere 10, no. 6 (2016): 3091–105. http://dx.doi.org/10.5194/tc-10-3091-2016.

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Abstract. High-altitude glaciers and ice caps from midlatitudes and tropical regions contain valuable signals of past climatic and environmental conditions as well as human activities, but for a meaningful interpretation this information needs to be placed in a precise chronological context. For dating the upper part of ice cores from such sites, several relatively precise methods exist, but they fail in the older and deeper parts, where plastic deformation of the ice results in strong annual layer thinning and a non-linear age–depth relationship. If sufficient organic matter such as plant, wo

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Oteiza, Patricia I., Alejandra G. Erlejman, Sandra V. Verstraeten, Carl L. Keen, and César G. Fraga. "Flavonoid-membrane Interactions: A Protective Role of Flavonoids at the Membrane Surface?" Clinical and Developmental Immunology 12, no. 1 (2005): 19–25. http://dx.doi.org/10.1080/10446670410001722168.

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Flavonoids can exert beneficial health effects through multiple mechanisms. In this paper, we address the important, although not fully understood, capacity of flavonoids to interact with cell membranes. The interactions of polyphenols with bilayers include: (a) the partition of the more non-polar compounds in the hydrophobic interior of the membrane, and (b) the formation of hydrogen bonds between the polar head groups of lipids and the more hydrophilic flavonoids at the membrane interface. The consequences of these interactions are discussed. The induction of changes in membrane physical pro

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Rashid, Harunur, Qian Qian Lu, Min Zeng, Yang Wang, and Zhao Wu Zhang. "Sea-Surface Characteristics of the Newfoundland Basin of the Northwest Atlantic Ocean during the Last 145,000 Years: A Study Based on the Sedimentological and Paleontological Proxies." Applied Sciences 11, no. 8 (2021): 3343. http://dx.doi.org/10.3390/app11083343.

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Dramatic changes occur in the sea-surface characteristics (i.e., temperature and salinity) and freshwater input due to the interaction of cold and fresh Labrador Current and warm and salty North Atlantic Current (NAC) on the southeast Grand Banks. As a result, the biological productivity and seasonal stratification of the upper water masses are intensified. Such changes must have been more dramatic during the glacial times due to the penetration of the Polar and Arctic fronts and southward migration of the Gulf Stream/NAC. However, the extent to which such changes impacted the sea-surface char

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Vita, Francesco, Fabrizio Corrado Adamo, Mario Campana, et al. "Macroscopic Biaxial Order in Multilayer Films of Bent-Core Liquid Crystals Deposited by Combined Langmuir–Blodgett/Langmuir–Schaefer Technique." Nanomaterials 14, no. 4 (2024): 357. http://dx.doi.org/10.3390/nano14040357.

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Bent-core liquid crystals, a class of mesogenic compounds with non-linear molecular structures, are well known for their unconventional mesophases, characterized by complex molecular (and supramolecular) ordering and often featuring biaxial and polar properties. In the nematic phase, their unique behavior is manifested in the formation of nano-sized biaxial clusters of layered molecules (cybotactic groups). While this prompted their consideration in the quest for nematic biaxiality, experimental evidence indicates that the cybotactic order is only short-ranged and that the nematic phase is mac

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Mulvaney, R., D. A. Peel, and A. P. Reid. "26-Year High Resolution Profile Of Major Anions In Snow From Coats Land, Antarctica." Annals of Glaciology 14 (1990): 349. http://dx.doi.org/10.3189/s0260305500009198.

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In January 1987, an 7.8 m core, with an age at the bottom of 26 years, was collected from a site approximately 150 km inland from Halley Station (77°02.2′S, 22°32′W; altitude 1862 m a.s.l.); 10 m temperature ≈ −30°C; accumulation rate ≈ 14 g cm−2 a−1). The site lies some 140 km from the coast of the Weddell Sea and within the area bounded in winter by the polar vortex.The core has been analysed at a frequency of ≈28 samples per accumulation year for sulphate, nitrate and chloride, and has been dated stratigraphically from the clear seasonal cycles in non sea salt sulphate (Mulvaney and Peel, 1

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