Life in Solid Ice on Earth and Other Planetary Bodies

Theory and direct observation indicate that micro-organisms exist in liquid veins in ice and permafrost, provided the temperature is above the eutectic for H2O and soluble impurities present. Microbes can exist and metabolize in glacial ice and permafrost on Earth, Mars, and Europa. One can search directly (with fluorescence microscopy at liquid veins in Vostok ice core samples) or with a biologging instrument (for microbial fluorescence in a borehole in terrestrial or martian permafrost or ice). The viability lifetime against DNA destruction of bacterial spores can be measured with analytical techniques that identify calcium dipicolinate, which is unique to spores.

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Air-hydrate crystals in deep ice-core samples from Vostok Station, Antarctica

Journal of Glaciology ◽

10.1017/s0022143000003828 ◽

1994 ◽

Vol 40 (134) ◽

pp. 79-86 ◽

Cited By ~ 49

Author(s):

T. Uchida ◽

T. Hondoh ◽

S. Mae ◽

V.YA. Lipenkov ◽

P. Duval

Keyword(s):

Volume Concentration ◽

Ice Core ◽

Site Occupancy ◽

Mean Value ◽

Gas Content ◽

Glacial Ice ◽

Core Samples ◽

Vostok Station ◽

The Mean ◽

Geometrical Equation

AbstractMicroscopic observation of air-hydrate crystals was carried out using 34 deep ice-core samples retrieved at Vostok Station, Antarctica. Samples were obtained from depths between 1050 and 2542 m, which correspond to Wisconsin/Sangamon/Illinoian ice. It was found that the volume and number of air-hydrate varied with the climatic changes. The volume concentration of air-hydrate in the interglacial ice was about 30% larger than that in the glacial ice. In the interglacial ice, the number concentration of air-hydrate was about a half and the mean volume of air-hydrate was nearly three times larger than that in the glacial-age ice. The air-hydrate crystals were found to grow in the ice sheet, about 6.7 × 10−12cm3year-1, in compensation for the disappearance of smaller ones. The volume concentration of air-hydrate was related to the total gas content by a geometrical equation with a proportional parameter α. The mean value of α below 1250 m, where no air bubbles were found, was about 0.79. This coincided with an experimentally determined value of the crystalline site occupancy of the air-hydrate in a 1500 m core obtained at Dye 3, Greenland (Hondoh and others, 1990). In the depth profile of calculated α for many samples, α in the interglacial ice was about 30% smaller than that in the glacial-age ice.

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Air-hydrate crystals in deep ice-core samples from Vostok Station, Antarctica

Journal of Glaciology ◽

10.3189/s0022143000003828 ◽

1994 ◽

Vol 40 (134) ◽

pp. 79-86 ◽

Cited By ~ 1

Author(s):

T. Uchida ◽

T. Hondoh ◽

S. Mae ◽

V.YA. Lipenkov ◽

P. Duval

Keyword(s):

Volume Concentration ◽

Ice Core ◽

Site Occupancy ◽

Mean Value ◽

Gas Content ◽

Glacial Ice ◽

Core Samples ◽

Vostok Station ◽

The Mean ◽

Geometrical Equation

AbstractMicroscopic observation of air-hydrate crystals was carried out using 34 deep ice-core samples retrieved at Vostok Station, Antarctica. Samples were obtained from depths between 1050 and 2542 m, which correspond to Wisconsin/Sangamon/Illinoian ice. It was found that the volume and number of air-hydrate varied with the climatic changes. The volume concentration of air-hydrate in the interglacial ice was about 30% larger than that in the glacial ice. In the interglacial ice, the number concentration of air-hydrate was about a half and the mean volume of air-hydrate was nearly three times larger than that in the glacial-age ice. The air-hydrate crystals were found to grow in the ice sheet, about 6.7 × 10−12 cm3 year-1, in compensation for the disappearance of smaller ones. The volume concentration of air-hydrate was related to the total gas content by a geometrical equation with a proportional parameter α. The mean value of α below 1250 m, where no air bubbles were found, was about 0.79. This coincided with an experimentally determined value of the crystalline site occupancy of the air-hydrate in a 1500 m core obtained at Dye 3, Greenland (Hondoh and others, 1990). In the depth profile of calculated α for many samples, α in the interglacial ice was about 30% smaller than that in the glacial-age ice.

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A comparison of annual layer thickness model estimates with observational measurements using the Berkner Island ice core, Antarctica

Antarctic Science ◽

10.1017/s0954102017000025 ◽

2017 ◽

Vol 29 (4) ◽

pp. 382-393

Author(s):

A. Massam ◽

S.B. Sneed ◽

G.P. Lee ◽

R.R. Tuckwell ◽

R. Mulvaney ◽

...

Keyword(s):

High Resolution ◽

Layer Thickness ◽

Inductively Coupled Plasma ◽

Ice Core ◽

Ultra Violet ◽

Analytical Techniques ◽

Inductively Coupled ◽

Annual Layer ◽

Icp Ms ◽

Chemical Profiles

AbstractA model to estimate the annual layer thickness of deposited snowfall at a deep ice core site, compacted by vertical strain with respect to depth, is assessed using ultra-high-resolution laboratory analytical techniques. A recently established technique of high-resolution direct chemical analysis of ice using ultra-violet laser ablation inductively-coupled plasma mass spectrometry (LA ICP-MS) has been applied to ice from the Berkner Island ice core, and compared with results from lower resolution techniques conducted on parallel sections of ice. The results from both techniques have been analysed in order to assess the capability of each technique to recover seasonal cycles from deep Antarctic ice. Results do not agree with the annual layer thickness estimates from the age–depth model for individual samples <1 m long as the model cannot reconstruct the natural variability present in annual accumulation. However, when compared with sections >4 m long, the deviation between the modelled and observational layer thicknesses is minimized to within two standard deviations. This confirms that the model is capable of successfully estimating mean annual layer thicknesses around analysed sections. Furthermore, our results confirm that the LA ICP-MS technique can reliably recover seasonal chemical profiles beyond standard analytical resolution.

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Antarctic ice core samples: culturable bacterial diversity

Research in Microbiology ◽

10.1016/j.resmic.2012.09.001 ◽

2013 ◽

Vol 164 (1) ◽

pp. 70-82 ◽

Cited By ~ 23

Author(s):

Sisinthy Shivaji ◽

Zareena Begum ◽

Singireesu Soma Shiva Nageswara Rao ◽

Puram V. Vishnu Vardhan Reddy ◽

Poorna Manasa ◽

...

Keyword(s):

Bacterial Diversity ◽

Ice Core ◽

Core Samples

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Evidence for a large surface ablation zone in central East Antarctica during the last Ice Age

Quaternary Research ◽

10.1016/s0033-5894(02)00014-5 ◽

2003 ◽

Vol 59 (1) ◽

pp. 114-121 ◽

Cited By ~ 26

Author(s):

Martin J. Siegert ◽

Richard C. A. Hindmarsh ◽

Gordon S. Hamilton

Keyword(s):

Ice Core ◽

Remote Sensing Data ◽

Ice Age ◽

Internal Layers ◽

Ice Flow ◽

Glacial Ice ◽

Ice Surface ◽

Ice Flows ◽

Last Ice Age ◽

The Hill

AbstractInternal isochronous ice sheet layers, recorded by airborne ice-penetrating radar, were measured along an ice flowline across a large (>1 km high) subglacial hill in the foreground of the Transantarctic Mountains. The layers, dated through an existing stratigraphic link with the Vostok ice core, converge with the ice surface as ice flows over the hill without noticeable change to their separation with each other or the ice base. A two-dimensional ice flow model that calculates isochrons and particle flowpaths and accounts for ice flow over the hill under steady-state conditions requires net ablation (via sublimation) over the stoss face for the predicted isochrons to match the measured internal layers. Satellite remote sensing data show no sign of exposed ancient ice at this site, however. Given the lack of exposed glacial ice, surface balance conditions must have changed recently from the net ablation that is predicted at this site for the last 85,000 years to accumulation.

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An automated GC-C-GC-IRMS setup to measure palaeoatmospheric δ13C-CH4, δ15N-N2O and δ18O-N2O in one ice core sample

Atmospheric Measurement Techniques ◽

10.5194/amt-6-2027-2013 ◽

2013 ◽

Vol 6 (8) ◽

pp. 2027-2041 ◽

Cited By ~ 12

Author(s):

P. Sperlich ◽

C. Buizert ◽

T. M. Jenk ◽

C. J. Sapart ◽

M. Prokopiou ◽

...

Keyword(s):

Ice Core ◽

Gold Catalyst ◽

Isotope Ratios ◽

Core Sample ◽

Ion Source ◽

Resolving Power ◽

Published Data ◽

Core Samples ◽

Stable Conditions ◽

Ch4 And N2o

Abstract. Air bubbles in ice core samples represent the only opportunity to study the mixing ratio and isotopic variability of palaeoatmospheric CH4 and N2O. The highest possible precision in isotope measurements is required to maximize the resolving power for CH4 and N2O sink and source reconstructions. We present a new setup to measure δ13C-CH4, δ15N-N2O and δ18O-N2O isotope ratios in one ice core sample and with one single IRMS instrument, with a precision of 0.09, 0.6 and 0.7‰, respectively, as determined on 0.6–1.6 nmol CH4 and 0.25–0.6 nmol N2O. The isotope ratios are referenced to the VPDB scale (δ13C-CH4), the N2-air scale (δ15N-N2O) and the VSMOW scale (δ18O-N2O). Ice core samples of 200–500 g are melted while the air is constantly extracted to minimize gas dissolution. A helium carrier gas flow transports the sample through the analytical system. We introduce a new gold catalyst to oxidize CO to CO2 in the air sample. CH4 and N2O are then separated from N2, O2, Ar and CO2 before they get pre-concentrated and separated by gas chromatography. A combustion unit is required for δ13C-CH4 analysis, which is equipped with a constant oxygen supply as well as a post-combustion trap and a post-combustion GC column (GC-C-GC-IRMS). The post-combustion trap and the second GC column in the GC-C-GC-IRMS combination prevent Kr and N2O interferences during the isotopic analysis of CH4-derived CO2. These steps increase the time for δ13C-CH4 measurements, which is used to measure δ15N-N2O and δ18O-N2O first and then δ13C-CH4. The analytical time is adjusted to ensure stable conditions in the ion source before each sample gas enters the IRMS, thereby improving the precision achieved for measurements of CH4 and N2O on the same IRMS. The precision of our measurements is comparable to or better than that of recently published systems. Our setup is calibrated by analysing multiple reference gases that were injected over bubble-free ice samples. We show that our measurements of δ13C-CH4 in ice core samples are generally in good agreement with previously published data after the latter have been corrected for krypton interferences.

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Concept and Testing of a Remotely Operated Vehicle-Mountable Inductive Electrothermal Polar Under-Ice Corer

Marine Technology Society Journal ◽

10.4031/mtsj.51.6.4 ◽

2017 ◽

Vol 51 (6) ◽

pp. 33-43 ◽

Cited By ~ 2

Author(s):

Narayanaswamy Vedachalam ◽

Arumugam Vadivelan ◽

Arunachalam Umapathy ◽

Munusamy Murugesan ◽

Gopal Durai ◽

...

Keyword(s):

Ice Core ◽

Input Power ◽

Design Development ◽

Polar Ice ◽

Remotely Operated Vehicle ◽

Element Analysis ◽

Ice Shelves ◽

Core Samples ◽

Inner Diameter ◽

Aided Design

AbstractIce core samples from the polar ice shelves contain valuable paleo-climatic records and information for understanding the unique polar under-ice ecosystem. This paper describes the finite element analysis-aided design, development, and qualification of a 63-mm-inner diameter, 250-mm-long variable power underwater remotely operated vehicle-mountable inductive ice corer (IIC) for collecting ice core samples beneath the polar ice shelves. It is determined that, with the IIC operating with an input power of 1,000 W at 30 kHz, it is possible to have an ice penetration rate of 14 mm/min and obtain an ice core of 51 mm in diameter. The experimental results are found to comply with the numerical model with an accuracy of 95%.

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Climate Change: What’s the Big Deal?

Paying for Pollution ◽

10.1093/oso/9780190694197.003.0002 ◽

2019 ◽

pp. 7-22

Author(s):

Gilbert E. Metcalf

Keyword(s):

Climate Change ◽

Greenhouse Gases ◽

Sea Level Rise ◽

Sea Level ◽

Ice Core ◽

Core Samples ◽

History Of ◽

The Cost ◽

Climate Damages

Droughts, floods, soaring temperatures, sea-level rise, and melting ice are just some of the damages brought about by climate change. Chapter 1 details the cost of our failure to cut our emissions, from crop-destroying droughts to devastating floods. It also documents the inexorable build-up of greenhouse gases in the atmosphere as demonstrated by the Keeling curve and observations from Antarctic ice core samples. The chapter then provides a brief history of the science linking the build-up of atmospheric greenhouse gases and climate damages.

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