On the Greenland ice sheet, a significant quantity of surface meltwater refreezes within the firn, creating uncertainty in surface mass balance estimates. This refreezing has the potential to buffer seasonal runoff to future increases in melting, but direct measurement of the process remains difficult. We present a method for quantifying refreezing at point locations using in situ firn temperat...

Glacier surface melt and runoff depend strongly on seasonal and perennial snow (firn) conditions. Not only does the presence of snow and firn directly affect melt rates by reflecting solar radiation, it may also act as a buffer against mass loss by storing melt water in refrozen or liquid form. In Svalbard, ongoing and projected amplified climate change with respect to the global mean change ha...

We investigate freezing characteristics of a finite dipolar hexagonal plate by the Monte Carlo simulation. The hexagonal plate is cut out from a piled triangular lattice of three layers with FCC-like (ABCABC) stacking structure. In the present study an annealing simulation is performed for the dipolar plate uniaxially compressed in the direction of layer-piling. We find spin melting and refreez...

Stereo topography of an area near Tyre impact crater, Europa, reveals chaos regions characterised by marginal cliffs and domical topography, rising to 100–200 m above the background plains. The regions contain blocks which have both rotated and tilted. We tested two models of chaos formation: a hybrid diapir model, in which chaos topography is caused by thermal or compositional buoyancy, and bl...

The presence of melt ponds on the surface of Arctic sea ice significantly reduces its albedo, inducing a positive feedback leading to sea ice thinning. While the role of melt ponds in enhancing the summer melt of sea ice is well known, their impact on suppressing winter freezing of sea ice has, hitherto, received less attention. Melt ponds freeze by forming an ice lid at the upper surface, whic...

OBJECTIVE To study the resistance of human spermatozoa to cryoinjury in repeated cycles of thaw-refreezing by using the fast liquid nitrogen vapor method. MATERIALS AND METHODS Semen specimens were obtained from sixteen normal and oligozoospermic individuals who required disposal at the sperm bank. Five of them had testicular cancer. Specimens were thawed and an aliquot was removed for analys...

A metal wire attached to a weight can cut through a block of ice without cutting it. This phenomenon is due to the fusion of ice under the wire, where the pressure is greater, and refreezing of water behind the wire, where the pressure is lower. Bottomley (1872) was the first to discover this effect. He also observed that a wire of low thermal conductivity, for a given diameter and mass, will p...

The spatial representation of accumulation measurements is a major limitation for current glacier mass balance monitoring approaches. Here, we present a method for estimating annual accumulation rates on a temperate Alpine glacier based on the interpretation of internal reflection horizons (IRHs) in helicopter-borne ground-penetrating radar (GPR) data. For each individual GPR measurement, the s...

[1] The large outflow channels of Chryse Planitia, Mars, are thought to have been carved by floodwaters discharged from an aquifer beneath a confining cryosphere. However, conventional models of groundwater flow require optimistically high permeabilities to produce, in a single flooding event, the discharge rates and volumes inferred from channel morphology. Additionally, discharge likely cease...