Ice blue

In situ cosmogenic radiocarbon production and 2-D ice flow line modeling for an Antarctic blue ice area

[1] Radiocarbon measurements at ice margin sites and blue ice areas can potentially be used for ice dating, ablation rate estimates and paleoclimatic reconstructions. Part of the measured signal comes from in situ cosmogenic C production in ice, and this component must be well understood before useful information can be extracted from C data. We combine cosmic ray scaling and production estimat...

Atmospheric composition 1 million years ago from blue ice in the Allan Hills, Antarctica.

Here, we present direct measurements of atmospheric composition and Antarctic climate from the mid-Pleistocene (∼1 Ma) from ice cores drilled in the Allan Hills blue ice area, Antarctica. The 1-Ma ice is dated from the deficit in (40)Ar relative to the modern atmosphere and is present as a stratigraphically disturbed 12-m section at the base of a 126-m ice core. The 1-Ma ice appears to represen...

Variations of oxygen isotopic compositions of silicate spherules collected from Antarctic blue ice

Introduction: Recent works suggest that unmelted, phillosilicate-bearing micrometeorites and hydrous interplanetary dust particles (IDPs) collected at stratosphere are related to hydrated carbonaceous chondrites [1], [2], which are supposed to be derived from C-, P-, D-, or T-type asteroids [3, 4]. Anhydrous IDPs are supposed to be cometary origin because of their high D/H ratios and characteri...

Simulation of Wind Fields at Scharffenbergbotten, Antarctica and their Impact on Blue Ice Areas

Production of Ice Nucleation Deficient (Ice-) Mutants of the Epiphytic Strains of Erwinia herbicola

To mutate the Ice Nucleation Active (INA) gene in Erwinia herbicola strains, Tn-5 transposon carried by Psup2021 plasmid was used. This plasmid was transferred to the bacterial cells by electroporation. Electrotransformation was carried out for 2.5 ms at 1800 v and 1 mm distance between the electrodes. Polymerase chain reaction was used for determination of presence or loss of INA gene, using a...