Journal articles: 'Melt loss'

1

Kriegsman, L. M. "Quantitative field methods for estimating melt production and melt loss." Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy 26, no. 4-5 (April 2001): 247–53. http://dx.doi.org/10.1016/s1464-1895(01)00052-7.

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Ni, Peng, Youxue Zhang, and Yunbin Guan. "Volatile loss during homogenization of lunar melt inclusions." Earth and Planetary Science Letters 478 (November 2017): 214–24. http://dx.doi.org/10.1016/j.epsl.2017.09.010.

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Mercer, Cameron M., and Kip V. Hodges. "Diffusive loss of argon in response to melt vein formation in polygenetic impact melt breccias." Journal of Geophysical Research: Planets 122, no. 8 (August 2017): 1650–71. http://dx.doi.org/10.1002/2017je005312.

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Djurdjevic, Mile, Srecko Manasijevic, Slavko Smiljanic, and Marko Ristic. "Quantification of Modifiers Fading during Melt Holding in the Aluminum Casting Furnace." Crystals 13, no. 2 (January 21, 2023): 191. http://dx.doi.org/10.3390/cryst13020191.

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Strontium (Sr) and sodium (Na) are the most used modifiers in the aluminum casting industry. Both lose their concentration (fade) during holding in the melting furnace. Three types of chemical reactions in the melt may cause modifier fading: vaporizing, oxidizing, or reacting with some other elements from the melt. Due to Na and Sr’s very low vapor pressure, their vaporization from the aluminum melt was excluded as a reason for the modifiers’ fading. Oxidation looks like the major chemical reaction that causes the fading of Na and Sr from an aluminum melt. The present paper aimed to quantify the fading of Na and Sr in an Al–Si–Cu–Mg alloy. The loss of modifiers (Na and Sr) during melt holding in a furnace can be analytically quantified using equations taken from the literature. The calculated surface reaction rate constant (ks) can estimate the modifier’s loss during melt holding in industrial and laboratory furnaces.

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Diamond, Rachel, Louise C. Sime, David Schroeder, and Maria-Vittoria Guarino. "The contribution of melt ponds to enhanced Arctic sea-ice melt during the Last Interglacial." Cryosphere 15, no. 11 (November 9, 2021): 5099–114. http://dx.doi.org/10.5194/tc-15-5099-2021.

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Abstract. The Hadley Centre Global Environment Model version 3 (HadGEM3) is the first coupled climate model to simulate an ice-free Arctic during the Last Interglacial (LIG), 127 000 years ago. This simulation appears to yield accurate Arctic surface temperatures during the summer season. Here, we investigate the causes and impacts of this extreme simulated ice loss. We find that the summer ice melt was predominantly driven by thermodynamic processes: atmospheric and ocean circulation changes did not significantly contribute to the ice loss. We demonstrate these thermodynamic processes were significantly impacted by melt ponds, which formed on average 8 d earlier during the LIG than during the pre-industrial control (PI) simulation. This relatively small difference significantly changed the LIG surface energy balance and impacted the albedo feedback. Compared to the PI simulation: in mid-June, of the absorbed flux at the surface over ice-covered cells (sea-ice concentration > 0.15), ponds accounted for 45 %–50 %, open water 35 %–45 %, and bare ice and snow 5 %–10 %. We show that the simulated ice loss led to large Arctic sea surface salinity and temperature changes. The sea surface temperature and salinity signals we identify here provide a means to verify, in marine observations, if and when an ice-free Arctic occurred during the LIG. Strong LIG correlations between spring melt pond and summer ice area indicate that, as Arctic ice continues to thin in future, the spring melt pond area will likely become an increasingly reliable predictor of the September sea-ice area. Finally, we note that models with explicitly modelled melt ponds seem to simulate particularly low LIG sea-ice area. These results show that models with explicit (as opposed to parameterised) melt ponds can simulate very different sea-ice behaviour under forcings other than the present day. This is of concern for future projections of sea-ice loss.

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Knapp, J. A., L. R. Thompson, and G. J. Collins. "The role of radiation in melt stability in zone-melt recrystallization of SOI." Journal of Materials Research 5, no. 5 (May 1990): 998–1002. http://dx.doi.org/10.1557/jmr.1990.0998.

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Under circumstances in Zone-Melt-Recrystallization (ZMR) of Si-on-Insulator (SOI) structures where radiative heat loss is significant, the ∼50% decrease in emissivity when Si melts destabilizes the Si molten zone. We have demonstrated this both experimentally using a slowly scanned e-beam line source and numerically with a finite-element computational simulation. The resulting instability narrows the process window and tightens requirements on beam control and background heating uniformity, both for e-beam ZMR systems and optically-coupled systems such as a graphite strip heater.

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7

Hall, Dorothy K., Richard S. Williams, Scott B. Luthcke, and Nicolo E. Digirolamo. "Greenland ice sheet surface temperature, melt and mass loss: 2000–06." Journal of Glaciology 54, no. 184 (2008): 81–93. http://dx.doi.org/10.3189/002214308784409170.

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AbstractA daily time series of ‘clear-sky’ surface temperature has been compiled of the Greenland ice sheet (GIS) using 1 km resolution moderate-resolution imaging spectroradiometer (MODIS) land-surface temperature (LST) maps from 2000 to 2006. We also used mass-concentration data from the Gravity Recovery and Climate Experiment (GRACE) to study mass change in relationship to surface melt from 2003 to 2006. The mean LST of the GIS increased during the study period by ∼0.27°C a−1. The increase was especially notable in the northern half of the ice sheet during the winter months. Melt-season length and timing were also studied in each of the six major drainage basins. Rapid (<15 days) and sustained mass loss below 2000 m elevation was triggered in 2004 and 2005 as recorded by GRACE when surface melt begins. Initiation of large-scale surface melt was followed rapidly by mass loss. This indicates that surface meltwater is flowing rapidly to the base of the ice sheet, causing acceleration of outlet glaciers, thus highlighting the metastability of parts of the GIS and the vulnerability of the ice sheet to air-temperature increases. If air temperatures continue to rise over Greenland, increased surface melt will play a large role in ice-sheet mass loss.

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White, R. W., and R. Powell. "Melt loss and the preservation of granulite facies mineral assemblages." Journal of Metamorphic Geology 20, no. 7 (September 2002): 621–32. http://dx.doi.org/10.1046/j.1525-1314.2002.00206.x.

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White, R. W., and R. Powell. "Melt loss and the preservation of granulite facies mineral assemblages." Journal of Metamorphic Geology 20, no. 7 (July 29, 2002): 621–32. http://dx.doi.org/10.1046/j.1525-1314.2002.00206_20_7.x.

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10

Burton, K. W., A. S. Cohen, and R. K. O'Nions. "Investigation of dehydration and melt loss in the lower crust." Chemical Geology 70, no. 1-2 (August 1988): 13. http://dx.doi.org/10.1016/0009-2541(88)90213-6.

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11

Chen, Yang, Ariel Provost, Pierre Schiano, and Nicolas Cluzel. "The rate of water loss from olivine-hosted melt inclusions." Contributions to Mineralogy and Petrology 162, no. 3 (February 24, 2011): 625–36. http://dx.doi.org/10.1007/s00410-011-0616-5.

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12

Lloyd, Alexander S., Terry Plank, Philipp Ruprecht, Erik H. Hauri, and William Rose. "Volatile loss from melt inclusions in pyroclasts of differing sizes." Contributions to Mineralogy and Petrology 165, no. 1 (September 28, 2012): 129–53. http://dx.doi.org/10.1007/s00410-012-0800-2.

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13

Levermann, Anders, and Ricarda Winkelmann. "A simple equation for the melt elevation feedback of ice sheets." Cryosphere 10, no. 4 (August 18, 2016): 1799–807. http://dx.doi.org/10.5194/tc-10-1799-2016.

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Abstract. In recent decades, the Greenland Ice Sheet has been losing mass and has thereby contributed to global sea-level rise. The rate of ice loss is highly relevant for coastal protection worldwide. The ice loss is likely to increase under future warming. Beyond a critical temperature threshold, a meltdown of the Greenland Ice Sheet is induced by the self-enforcing feedback between its lowering surface elevation and its increasing surface mass loss: the more ice that is lost, the lower the ice surface and the warmer the surface air temperature, which fosters further melting and ice loss. The computation of this rate so far relies on complex numerical models which are the appropriate tools for capturing the complexity of the problem. By contrast we aim here at gaining a conceptual understanding by deriving a purposefully simple equation for the self-enforcing feedback which is then used to estimate the melt time for different levels of warming using three observable characteristics of the ice sheet itself and its surroundings. The analysis is purely conceptual in nature. It is missing important processes like ice dynamics for it to be useful for applications to sea-level rise on centennial timescales, but if the volume loss is dominated by the feedback, the resulting logarithmic equation unifies existing numerical simulations and shows that the melt time depends strongly on the level of warming with a critical slowdown near the threshold: the median time to lose 10 % of the present-day ice volume varies between about 3500 years for a temperature level of 0.5 °C above the threshold and 500 years for 5 °C. Unless future observations show a significantly higher melting sensitivity than currently observed, a complete meltdown is unlikely within the next 2000 years without significant ice-dynamical contributions.

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14

Goelles, T., C. E. Bøggild, and R. Greve. "Ice sheet mass loss caused by dust and black carbon accumulation." Cryosphere Discussions 9, no. 2 (April 23, 2015): 2563–96. http://dx.doi.org/10.5194/tcd-9-2563-2015.

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Abstract. Albedo is the dominating factor governing surface melt variability in the ablation area of ice sheets and glaciers. Aerosols such as mineral dust and black carbon (soot) accumulate on the ice surface and cause a darker surface and therefore a lower albedo. The dominant source of these aerosols in the ablation area is melt-out of englacial material which has been transported via ice flow. The darkening effect on the ice surface is currently not included in sea level projections, and the effect is unknown. We present a model framework which includes ice dynamics, aerosol transport, aerosol accumulation and the darkening effect on ice albedo and its consequences for surface melt. The model is applied to a simplified geometry resembling the conditions of the Greenland ice sheet, and it is forced by several temperature scenarios to quantify the darkening effect of aerosols on future mass loss. The effect of aerosols depends non-linearly on the temperature rise due to the feedback between aerosol accumulation and surface melt. The effect of aerosols in the year 3000 is up to 12% of additional ice sheet volume loss in the warmest scenario.

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15

Chernos, M., M. Koppes, and R. D. Moore. "The relative contributions of calving and surface ablation to ice loss at a lake-terminating glacier." Cryosphere Discussions 9, no. 3 (May 27, 2015): 2915–53. http://dx.doi.org/10.5194/tcd-9-2915-2015.

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Abstract. Bridge Glacier is a lake-terminating glacier in the Coast Mountains of British Columbia and has retreated over 3.55 km since 1972, with the majority of the retreat having occurred since 1991. This retreat is out of proportion to surface melt inferred from regional climate indices, suggesting that it has been driven primarily by calving as the glacier retreated across an over-deepened basin. In order to better understand the primary drivers of mass balance, the relative importance of surface melt and calving is investigated during the 2013 melt season using a distributed energy balance model and time-lapse imagery. Calving is responsible for 23% of the mass loss during the 2013 melt season, and is limited by modest flow speeds and a small terminus cross-section. Calving and summer balance estimates over the last 30 years suggest that calving is consistently a smaller contributor of mass loss relative to surface melt. Although calving is estimated to be responsible for up to 49% of ice loss for individual seasons, averaged over multiple summers it typically accounts for 10 to 25%. Calving has been driven primarily by buoyancy and water depths, and fluxes were greatest between 2005 and 2010 as the glacier retreated over the deepest part of Bridge Lake. These losses are part of a transient stage in the glacier's retreat, and are expected to diminish as the terminus recedes into shallower water. Surface melt is the primary driver of ice loss at Bridge Glacier, and future mass loss and retreat is dependent on governing climatic conditions.

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16

Morrissey, Laura J., Martin Hand, Kathleen Lane, David E. Kelsey, and Rian A. Dutch. "Upgrading iron-ore deposits by melt loss during granulite facies metamorphism." Ore Geology Reviews 74 (April 2016): 101–21. http://dx.doi.org/10.1016/j.oregeorev.2015.11.012.

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17

Stroeve, J. C., T. Markus, L. Boisvert, J. Miller, and A. Barrett. "Changes in Arctic melt season and implications for sea ice loss." Geophysical Research Letters 41, no. 4 (February 22, 2014): 1216–25. http://dx.doi.org/10.1002/2013gl058951.

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18

Ortiz, Diana L., and Robert L. Shambaugh. "Melt-Spun Polybutylene Fibers and Nonwovens." International Nonwovens Journal os-14, no. 4 (December 2005): 1558925005os—14. http://dx.doi.org/10.1177/1558925005os-1400405.

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Polybutylene (PB-1) fibers were spun at spinning speeds of 250–2500 m/min. A tensile tester was used to analyze the stress-strain behavior of these fibers. In addition, birefringence and the effect of aging were examined. A DMA (dynamic mechanical analyzer) was used to measure the storage modulus and loss modulus of the fibers. Nonwoven mats of the fibers were prepared and compression tests were run on these mats. The properties of the polybutylene fibers and mats were compared with the properties of common polypropylene fibers and mats.

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19

Ryan, J. C., L. C. Smith, D. van As, S. W. Cooley, M. G. Cooper, L. H. Pitcher, and A. Hubbard. "Greenland Ice Sheet surface melt amplified by snowline migration and bare ice exposure." Science Advances 5, no. 3 (March 2019): eaav3738. http://dx.doi.org/10.1126/sciadv.aav3738.

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Greenland Ice Sheet mass loss has recently increased because of enhanced surface melt and runoff. Since melt is critically modulated by surface albedo, understanding the processes and feedbacks that alter albedo is a prerequisite for accurately forecasting mass loss. Using satellite imagery, we demonstrate the importance of Greenland’s seasonally fluctuating snowline, which reduces ice sheet albedo and enhances melt by exposing dark bare ice. From 2001 to 2017, this process drove 53% of net shortwave radiation variability in the ablation zone and amplified ice sheet melt five times more than hydrological and biological processes that darken bare ice itself. In a warmer climate, snowline fluctuations will exert an even greater control on melt due to flatter ice sheet topography at higher elevations. Current climate models, however, inaccurately predict snowline elevations during high melt years, portending an unforeseen uncertainty in forecasts of Greenland’s runoff contribution to global sea level rise.

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20

Mackie, Shona, Inga J. Smith, Jeff K. Ridley, David P. Stevens, and Patricia J. Langhorne. "Climate Response to Increasing Antarctic Iceberg and Ice Shelf Melt." Journal of Climate 33, no. 20 (October 15, 2020): 8917–38. http://dx.doi.org/10.1175/jcli-d-19-0881.1.

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AbstractMass loss from the Antarctic continent is increasing; however, climate models either assume a constant mass loss rate or return snowfall over land to the ocean to maintain equilibrium. Numerous studies have investigated sea ice and ocean sensitivity to this assumption and reached different conclusions, possibly due to different representations of melt fluxes. The coupled atmosphere–land–ocean–sea ice model, HadGEM3-GC3.1, includes a realistic spatial distribution of coastal melt fluxes, a new ice shelf cavity parameterization, and explicit representation of icebergs. This configuration makes it appropriate to revisit how increasing melt fluxes influence ocean and sea ice and to assess whether responses to melt from ice shelves and icebergs are distinguishable. We present results from simulated scenarios of increasing meltwater fluxes and show that these drive sea ice increases and, for increasing ice shelf melt, a decline in Antarctic Bottom Water formation. In our experiments, the mixed layer around the Antarctic coast deepens in response to rising ice shelf meltwater and shallows in response to stratification driven by iceberg melt. We find similar surface temperature and salinity responses to increasing meltwater fluxes from ice shelves and icebergs, but midlayer waters warm to greater depths and farther north when ice shelf melt is present. We show that as meltwater fluxes increase, snowfall becomes more likely at lower latitudes and Antarctic Circumpolar Current transport declines. These insights are helpful for interpretation of climate simulations that assume constant mass loss rates and demonstrate the importance of representing increasing melt rates for both ice shelves and icebergs.

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21

Brown, Michael. "Melting of the continental crust during orogenesis: the thermal, rheological, and compositional consequences of melt transport from lower to upper continental crustThis article is one of a selection of papers published in this Special Issue on the the theme Lithoprobe—parameters, processes, and the evolution of a continent." Canadian Journal of Earth Sciences 47, no. 5 (May 2010): 655–94. http://dx.doi.org/10.1139/e09-057.

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The formation and differentiation of the continental crust occurs at convergent plate margins in accretionary and collisional orogenic belts where sufficient heat is generated to achieve high-grade metamorphism and anatexis. Volumetrically significant H2O-present melting requires an influx of aqueous fluid along zones of high-strain deformation or via fracture networks, or recycling of the fluid dissolved in melt via melt migration and fluid exsolution during crystallization. In contrast, in “dry” crust, melting occurs via hydrate-breakdown melting reactions at higher temperatures than H2O-present melting; volumetrically significant melt production requires temperatures above ∼800 °C. Melting wets residual grains, and anatectic crust becomes porous at a few vol.% melt. Feedback between deformation and melting creates a dynamic rheological environment; as melt volume increases to the melt connectivity transition, which varies but is around 7 vol.% (see discussion later in the text), melt may escape from the source in the first of several melt-loss events with increasing temperature. Major and accessory phase controls on melt production and melt composition for different pressure–temperature–time paths are evaluated using calculated phase equilibria for average pelite. The pristine to slightly retrogressed condition of peritectic minerals in residual crust requires significant loss of melt from the system. The consequences of melt loss are evaluated here. In residual crust, evidence of melt at the grain scale may be preserved in microstructures, whereas evidence of melt extraction pathways at outcrop scale is recorded by leucosome networks. Strain and anisotropy of permeability control the form of mesoscale melt channels with strong anisotropy promoting high-melt focusing. The sequence of structures observed in nature records a transition from storage to drainage; focused melt flow occurs by dilatant shear failure of low-melt-fraction rocks, leading to the formation of networks of channels that allow accumulation and storage of melt and that form the link for melt flow from grain boundaries to ascent conduits. Melt ascent is via ductile-to-brittle fracture; ductile fractures may propagate along foliation as sills or from dilation or shear bands as dikes. Emplacement of horizontal tabular and wedge-shaped plutons occurs around the brittle–ductile transition zone, whereas vertical lozenge-shaped plutons represent crystallization of magma in the ascent conduit. Blobby plutons form by lateral expansion in the ascent conduit localized by thermal or mechanical instabilities.

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22

Hulth, John. "Using a draw-wire sensor to continuously monitor glacier melt." Journal of Glaciology 56, no. 199 (2010): 922–24. http://dx.doi.org/10.3189/002214310794457290.

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AbstractA draw-wire sensor has successfully been used to measure surface lowering due to net ablation of a glacier. A thin steel wire attached to a weight is inserted and frozen into a borehole in the ice. The draw-wire sensor, installed on a tetrahedron on the surface, retracts the wire as the snow or ice melts. Relative surface lowering of the melting surface is recorded in a data logger and may be converted to mass loss. The instrument continuously logs net ablation over several melt seasons and has the potential to be used extensively in future studies of glacier melt, whenever high temporal resolution and precision are required.

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23

Taylor, John A., M. Prakash, G. G. Pereira, P. Rohan, Michael Lee, and Barbara Rinderer. "Predicting Dross Formation in Aluminium Melt Transfer Operations." Materials Science Forum 630 (October 2009): 37–44. http://dx.doi.org/10.4028/www.scientific.net/msf.630.37.

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Aluminium melt transfer operations can lead to significant amounts of dross formation as a result of chemical oxidation and physical entrapment processes. It has been suggested that these activities may contribute up to 50% of the total metal loss of ~1% in a typical primary aluminium smelter (i.e. 2,500 tonne/annum (tpa) in a smelter of 500,000tpa output). This is a large financial loss to any company, and also, in the new CO2-conscious era, it also represents a significant carbon footprint to ameliorate. A significant proportion of this metal loss may be prevented by adopting more efficient melt transfer strategies that reduce splashing and turbulence thereby resulting in reduced oxide and therefore dross formation. Optimisation of such systems is normally achieved by trial-and-error approaches, however a clear opportunity exists for rapid optimisation by employing computational modelling to explore the effects of changed equipment design and process conditions, such as tilt speed, spout height, spout geometry, etc. In the present paper, the Smoothed Particle Hydrodynamics (SPH) modeling method is used to predict the amount of oxide generated during molten metal transfers from a 500kg capacity tilting crucible furnace into a heated sow mould. Various conditions were tested. An oxidation model based on skimming trials performed in a laboratory-scale (8kg) oxidation rig is employed in the simulation. The predicted oxide from the simulations is compared against those of the experimental pours. It is anticipated that the validated model will be used for modifying the design and optimizing the operation of various melt transfer operations occurring in the aluminium industry.

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Wang, S., Y. M. Jiang, Y. F. Liang, F. Ye, and J. P. Lin. "Magnetic Properties and Core Loss Behavior of Fe-6.5wt.%Si Ribbons Prepared by Melt Spinning." Advances in Materials Science and Engineering 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/410830.

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Fe-6.5wt.%Si alloy is prepared in the form of continuous ribbons with 25 mm in width and 0.03 mm in thickness by using melt spinning technique. The ribbons are flexible and could be wounded into tapes. DC magnetic properties and core loss behaviors of the ribbons after heat treatment are investigated in this paper. The magnetic properties are compared with ribbons by cold rolling and CVD methods. The melt spinning ribbons exhibit much less core loss in the frequencies more than 10 kHz. The melt spinning ribbons are promising to be used for electric devices used in medium or higher frequencies.

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Sankar, M., K. V. Mirji, V. V. Satya Prasad, R. G. Baligidad, and A. A. Gokhale. "Purification of Niobium by Electron Beam Melting." High Temperature Materials and Processes 35, no. 6 (June 1, 2016): 621–27. http://dx.doi.org/10.1515/htmp-2014-0218.

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AbstractPure niobium metal, produced by alumino-thermic reduction of niobium oxide, contains various impurities which need to be reduced to acceptable levels to obtain aerospace grade purity. In the present work, an attempt has been made to refine niobium metals by electron beam drip melting technique to achieve purity confirming to the ASTM standard. Input power to the electron gun and melt rate were varied to observe their combined effect on extend of refining and loss of niobium. Electron beam (EB) melting is shown to reduce alkali metals, trace elements and interstitial impurities well below the specified limits. The reduction in the impurities during EB melting is attributed to evaporation and degassing due to the combined effect of high vacuum and high melt surface temperature. The % removal of interstitial impurities is essentially a function of melt rate and input power. As the melt rate decreases or input power increases, the impurity levels in the solidified niobium ingot decrease. The EB refining process is also accompanied by considerable amount of niobium loss, which is attributed to evaporation of pure niobium and niobium sub-oxide. Like other impurities, Nb loss increases with decreasing melt rate or increase in input power.

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Oltmanns, Marilena, Fiammetta Straneo, and Marco Tedesco. "Increased Greenland melt triggered by large-scale, year-round cyclonic moisture intrusions." Cryosphere 13, no. 3 (March 7, 2019): 815–25. http://dx.doi.org/10.5194/tc-13-815-2019.

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Abstract. Surface melting is a major driver of Greenland's mass loss. Yet, the mechanisms that trigger melt are still insufficiently understood because seasonally based studies blend processes initiating melt with positive feedbacks. Here, we focus on the triggers of melt by examining the synoptic atmospheric conditions associated with 313 rapid melt increases, detected in a satellite-derived melt extent product, equally distributed throughout the year over the period 1979–2012. By combining reanalysis and weather station data, we show that melt is initiated by a cyclone-driven, southerly flow of warm, moist air, which gives rise to large-scale precipitation. A decomposition of the synoptic atmospheric variability over Greenland suggests that the identified, melt-triggering weather pattern accounts for ∼40 % of the net precipitation, but increases in the frequency, duration and areal extent of the initiated melting have shifted the line between mass gain and mass loss as more melt and rainwater run off or accumulate in the snowpack. Using a regional climate model, we estimate that the initiated melting more than doubled over the investigated period, amounting to ∼28 % of the overall surface melt and revealing that, despite the involved mass gain, year-round precipitation events are participating in the ice sheet's decline.

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Goelles, T., C. E. Bøggild, and R. Greve. "Ice sheet mass loss caused by dust and black carbon accumulation." Cryosphere 9, no. 5 (September 22, 2015): 1845–56. http://dx.doi.org/10.5194/tc-9-1845-2015.

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Abstract. Albedo is the dominant factor governing surface melt variability in the ablation area of ice sheets and glaciers. Aerosols such as mineral dust and black carbon (soot) accumulate on the ice surface and cause a darker surface and therefore a lower albedo. The darkening effect on the ice surface is currently not included in sea level projections, and the effect is unknown. We present a model framework which includes ice dynamics, aerosol transport, aerosol accumulation and the darkening effect on ice albedo and its consequences for surface melt. The model is applied to a simplified geometry resembling the conditions of the Greenland ice sheet, and it is forced by several temperature scenarios to quantify the darkening effect of aerosols on future mass loss. The effect of aerosols depends non-linearly on the temperature rise due to the feedback between aerosol accumulation and surface melt. According to our conceptual model, accounting for black carbon and dust in future projections of ice sheet changes until the year 3000 could induce an additional volume loss of 7 %. Since we have ignored some feedback processes, the impact might be even larger.

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Tjønnås, Maria Suong, Hilde Færevik, Mariann Sandsund, and Randi E. Reinertsen. "The dry-heat loss effect of melt-spun phase change material fibres." Ergonomics 58, no. 3 (December 20, 2014): 535–42. http://dx.doi.org/10.1080/00140139.2014.975749.

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29

Hamilton, D. L., and S. Oxtoby. "Solubility of Water in Albite-Melt Determined by the Weight-Loss Method." Journal of Geology 94, no. 4 (July 1986): 626–30. http://dx.doi.org/10.1086/629064.

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30

Jäggi, Noah, Diana Gamborino, Dan J. Bower, Paolo A. Sossi, Aaron S. Wolf, Apurva V. Oza, Audrey Vorburger, André Galli, and Peter Wurz. "Evolution of Mercury’s Earliest Atmosphere." Planetary Science Journal 2, no. 6 (November 17, 2021): 230. http://dx.doi.org/10.3847/psj/ac2dfb.

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Abstract MESSENGER observations suggest a magma ocean formed on proto-Mercury, during which evaporation of metals and outgassing of C- and H-bearing volatiles produced an early atmosphere. Atmospheric escape subsequently occurred by plasma heating, photoevaporation, Jeans escape, and photoionization. To quantify atmospheric loss, we combine constraints on the lifetime of surficial melt, melt composition, and atmospheric composition. Consideration of two initial Mercury sizes and four magma ocean compositions determines the atmospheric speciation at a given surface temperature. A coupled interior–atmosphere model determines the cooling rate and therefore the lifetime of surficial melt. Combining the melt lifetime and escape flux calculations provides estimates for the total mass loss from early Mercury. Loss rates by Jeans escape are negligible. Plasma heating and photoionization are limited by homopause diffusion rates of ∼106 kg s−1. Loss by photoevaporation depends on the timing of Mercury formation and assumed heating efficiency and ranges from ∼106.6 to ∼109.6 kg s−1. The material for photoevaporation is sourced from below the homopause and is therefore energy limited rather than diffusion limited. The timescale for efficient interior–atmosphere chemical exchange is less than 10,000 yr. Therefore, escape processes only account for an equivalent loss of less than 2.3 km of crust (0.3% of Mercury’s mass). Accordingly, ≤0.02% of the total mass of H2O and Na is lost. Therefore, cumulative loss cannot significantly modify Mercury’s bulk mantle composition during the magma ocean stage. Mercury’s high core:mantle ratio and volatile-rich surface may instead reflect chemical variations in its building blocks resulting from its solar-proximal accretion environment.

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31

Enderlin, Ellyn M., and Ian M. Howat. "Submarine melt rate estimates for floating termini of Greenland outlet glaciers (2000–2010)." Journal of Glaciology 59, no. 213 (2013): 67–75. http://dx.doi.org/10.3189/2013jog12j049.

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AbstractThe rate of mass loss from the Greenland ice sheet has increased over the past decade due, in large part, to changes in marine-terminating outlet glacier dynamics. These changes are attributed to increased submarine melt rates of floating ice tongues and submerged calving faces resulting from increased coastal ocean heat transport. We use remotely sensed data to calculate submarine melt rates for 13 marine-terminating outlet glaciers in Greenland on a semi-annual basis between 2000 and 2010. We assess temporal and spatial variability in the calculated submarine melt rates and compare those variabilities to concurrent glacier change and offshore ocean temperatures. Over the period of study, average melt rates ranged from 0.03 to 2.98 m d−1 and account for 5–85% of the total volume loss from the floating ice tongue, with no clear spatial pattern. Only four glaciers show substantial interannual variability in melt rate during the decade. Melt rates were uncorrelated with front retreat, speed and changes in ocean temperature. Although the small sample size limits our analysis of the relationship between oceanographic forcing and glacier response, these data suggest that the calving rate may vary with discharge but that submarine melt rates are independent of grounding line discharge.

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Woo, Ming-ko, and Mark A. Giesbrecht. "Simulation of Snowmelt in a Subarctic Spruce Woodland: Scale Considerations." Hydrology Research 31, no. 4-5 (August 1, 2000): 301–16. http://dx.doi.org/10.2166/nh.2000.0018.

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Subarctic woodlands comprise stands of spruce trees with varying degrees of openness, giving rise to large contrasts in melt rates within the forest. The spatial variability of the changing snow depth during a melt season was investigated at three scales (2,4 and 16 m), using an example from a site in Yukon, Canada, where the computation of snowmelt takes into account the differential rates within the woodland. During the melt period, the mean daily snow depth decreases but the variability increases as continued ablation leads to greater unevenness of the snow cover. At the three scales of representation, increasing the grid size results in a reduction in the standard deviation and the skewness of depth distribution. The blurring of snow cover pattern at the larger scales is due to a loss in information, considered as the absolute value of the difference in snow depth calculated at two scales for the same location. This loss increases as the snow depth becomes more variable during the melt season. Knowledge of the scale-induced information loss is relevant to the modelling of snowmelt that exhibits large spatial variations.

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Robinson, A., and H. Goelzer. "The importance of insolation changes for paleo ice sheet modeling." Cryosphere 8, no. 4 (August 5, 2014): 1419–28. http://dx.doi.org/10.5194/tc-8-1419-2014.

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Abstract. The growth and retreat of continental ice sheets in the past has largely been a response to changing climatic forcing. Since ablation is the principal component of mass loss for land-based ice sheets, the calculation of surface melt is an important aspect of paleo ice sheet modeling. Changes in insolation are often not accounted for in calculations of surface melt, under the assumption that the near-surface temperature transmits the majority of the climatic forcing to the ice sheet. To assess how this could affect paleo simulations, here we investigate the importance of different orbital configurations for estimating melt on the Greenland ice sheet. We find that during peak Eemian conditions, increased insolation contributes 20–50% to the surface melt anomaly. However, this percentage depends strongly on the temperature anomaly at the time. For higher temperature anomalies, the role of insolation changes is less important. This relationship is not homogenous over the ice sheet, since the contribution of insolation to melt is modulated by the local surface albedo. In coupled simulations, the additional insolation-induced melt translates into up to threefold more ice volume loss, compared to output using a model that does not account for insolation changes. We also introduce a simple correction factor that allows reduced-complexity melt models to account for changes in insolation.

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Pachner, S., W. Roland, M. Aigner, C. Marschik, U. Stritzinger, and J. Miethlinger. "Using Symbolic Regression Models to Predict the Pressure Loss of Non-Newtonian Polymer-Melt Flows through Melt-Filtration Systems with Woven Screens." International Polymer Processing 36, no. 4 (September 1, 2021): 435–50. http://dx.doi.org/10.1515/ipp-2020-4019.

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Abstract When selecting a melt-filtration system, the initial pressure drop is a critical parameter. We used heuristic optimization algorithms to develop general analytical equations for estimating the dimensionless pressure loss of square and Dutch woven screens in polymer processing and recycling. We present a mathematical description – without the need for further numerical methods – of the dimensionless pressure loss of non-Newtonian polymer melt-flows through woven screens. Applying the theory of similarity, we first simplified, and then transformed into dimensionless form, the governing equations. By varying the characteristic independent dimensionless influencing parameters, we created a comprehensive parameter set. For each design point, the nonlinear governing equations were solved numerically. We subsequently applied symbolic regression based on genetic programming to develop models for the dimensionless pressure drop. Finally, we validated our models against experiments using both virgin and slightly contaminated in-house and post-industrial recycling materials. Our regression models predict the experimental data accurately, yielding a mean relative error of MRE = 13.7%. Our modeling approach, the accuracy of which we have proven, allows fast and stable prediction of the initial pressure drop of polymer-melt flows through square woven and Dutch weave screens, rendering further numerical simulations unnecessary.

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Serikov, V. A., R. A. Bikeev, M. V. Cherednichenko, and V. S. Cherednichenko. "Metal loss and charge heating in the melt in an electric arc furnace." Russian Metallurgy (Metally) 2015, no. 12 (December 2015): 980–84. http://dx.doi.org/10.1134/s0036029515120137.

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Ahmadian Baghbaderani, Hasan, Ansar Masood, Zoran Pavlovic, Kenny L. Alvarez, Cian ÓMathúna, Paul McCloskey, and Plamen Stamenov. "On the mechanisms limiting power loss in amorphous CoFeB-based melt-spun ribbons." Journal of Magnetism and Magnetic Materials 502 (May 2020): 166535. http://dx.doi.org/10.1016/j.jmmm.2020.166535.

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Korhonen, F. J., S. Saito, M. Brown, and C. S. Siddoway. "Modeling multiple melt loss events in the evolution of an active continental margin." Lithos 116, no. 3-4 (May 2010): 230–48. http://dx.doi.org/10.1016/j.lithos.2009.09.004.

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Gwyther, D. E., B. K. Galton-Fenzi, J. R. Hunter, and J. L. Roberts. "Simulated melt rates for the Totten and Dalton ice shelves." Ocean Science 10, no. 3 (May 6, 2014): 267–79. http://dx.doi.org/10.5194/os-10-267-2014.

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Abstract. The Totten Glacier is rapidly losing mass. It has been suggested that this mass loss is driven by changes in oceanic forcing; however, the details of the ice–ocean interaction are unknown. Here we present results from an ice shelf–ocean model of the region that includes the Totten, Dalton and Moscow University ice shelves, based on the Regional Oceanic Modeling System for the period 1992–2007. Simulated area-averaged basal melt rates (net basal mass loss) for the Totten and Dalton ice shelves are 9.1 m ice yr−1 (44.5 Gt ice yr−1) and 10.1 m ice yr−1 (46.6 Gt ice yr−1), respectively. The melting of the ice shelves varies strongly on seasonal and interannual timescales. Basal melting (mass loss) from the Totten ice shelf spans a range of 5.7 m ice yr−1 (28 Gt ice yr−1) on interannual timescales and 3.4 m ice yr−1 (17 Gt ice yr−1) on seasonal timescales. This study links basal melt of the Totten and Dalton ice shelves to warm water intrusions across the continental shelf break and atmosphere–ocean heat exchange. Totten ice shelf melting is high when the nearby Dalton polynya interannual strength is below average, and vice versa. Melting of the Dalton ice shelf is primarily controlled by the strength of warm water intrusions across the Dalton rise and into the ice shelf cavity. During periods of strong westward coastal current flow, Dalton melt water flows directly under the Totten ice shelf further reducing melting. This is the first such modelling study of this region to provide a valuable framework for directing future observational and modelling efforts.

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Robel, Alexander A., Earle Wilson, and Helene Seroussi. "Layered seawater intrusion and melt under grounded ice." Cryosphere 16, no. 2 (February 8, 2022): 451–69. http://dx.doi.org/10.5194/tc-16-451-2022.

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Abstract. Increasing melt of ice sheets at their floating or vertical interfaces with the ocean is a major driver of marine ice sheet retreat and sea level rise. However, the extent to which warm, salty seawater may drive melting under the grounded portions of ice sheets is still not well understood. Previous work has explored the possibility that dense seawater intrudes beneath relatively light subglacial freshwater discharge, similar to the “salt wedge” observed in many estuarine systems. In this study, we develop a generalized theory of layered seawater intrusion under grounded ice, including where subglacial hydrology occurs as a macroporous water sheet over impermeable beds or as microporous Darcy flow through permeable till. Using predictions from this theory, we show that seawater intrusion over flat or reverse-sloping impermeable beds may feasibly occur up to tens of kilometers upstream of a glacier terminus or grounding line. On the other hand, seawater is unlikely to intrude more than tens of meters through permeable till. Simulations using the Ice-sheet and Sea-level System Model (ISSM) show that even just a few hundred meters of basal melt caused by seawater intrusion upstream of marine ice sheet grounding lines can cause projections of marine ice sheet volume loss to be 10 %–50 % higher. Kilometers of intrusion-induced basal melt can cause projected ice sheet volume loss to more than double. These results suggest that further observational, experimental and numerical investigations are needed to determine the conditions under which seawater intrusion occurs and whether it will indeed drive rapid marine ice sheet retreat and sea level rise in the future.

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Zeitz, Maria, Ronja Reese, Johanna Beckmann, Uta Krebs-Kanzow, and Ricarda Winkelmann. "Impact of the melt–albedo feedback on the future evolution of the Greenland Ice Sheet with PISM-dEBM-simple." Cryosphere 15, no. 12 (December 20, 2021): 5739–64. http://dx.doi.org/10.5194/tc-15-5739-2021.

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Abstract. Surface melting of the Greenland Ice Sheet contributes a large amount to current and future sea level rise. Increased surface melt may lower the reflectivity of the ice sheet surface and thereby increase melt rates: the so-called melt–albedo feedback describes this self-sustaining increase in surface melting. In order to test the effect of the melt–albedo feedback in a prognostic ice sheet model, we implement dEBM-simple, a simplified version of the diurnal Energy Balance Model dEBM, in the Parallel Ice Sheet Model (PISM). The implementation includes a simple representation of the melt–albedo feedback and can thereby replace the positive-degree-day melt scheme. Using PISM-dEBM-simple, we find that this feedback increases ice loss through surface warming by 60 % until 2300 for the high-emission scenario RCP8.5 when compared to a scenario in which the albedo remains constant at its present-day values. With an increase of 90 % compared to a fixed-albedo scenario, the effect is more pronounced for lower surface warming under RCP2.6. Furthermore, assuming an immediate darkening of the ice surface over all summer months, we estimate an upper bound for this effect to be 70 % in the RCP8.5 scenario and a more than 4-fold increase under RCP2.6. With dEBM-simple implemented in PISM, we find that the melt–albedo feedback is an essential contributor to mass loss in dynamic simulations of the Greenland Ice Sheet under future warming.

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Zhang, Zong Bo, Qing Qiang He, and Cao Qing Yan. "Non-Melt Ultrasonic Bonding Method for Polymer MEMS Devices." Applied Mechanics and Materials 607 (July 2014): 133–38. http://dx.doi.org/10.4028/www.scientific.net/amm.607.133.

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Based on the theoretical study in our previous work, a novel thermal assisted ultrasonic bonding method for polymer Micro/nanoElectro-Mechanical Systems (M/NEMS) has been demonstrated. Bonding experiments of PMMA microfluidic chips with micro-channel of 80 μm in depth and width were conducted. The result shows numerous superiorities of this method including high bonding strength (0.95 MPa), low dimension loss (0.8% in depth and 0.3% in width, respectively) and short bonding duration.

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Gwyther, D. E., B. K. Galton-Fenzi, J. R. Hunter, and J. L. Roberts. "Simulated melt rates for the Totten and Dalton ice shelves." Ocean Science Discussions 10, no. 6 (November 13, 2013): 2109–40. http://dx.doi.org/10.5194/osd-10-2109-2013.

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Abstract. The Totten Glacier drains a large proportion of the East Antarctic ice sheet, much of it marine based (grounded below sea level), and is rapidly losing mass. It has been suggested that this mass loss is driven by changes in oceanic forcing; however, the details of the ice-ocean interaction are unknown. Here we present results from an ice shelf-ocean model of the region that includes the Totten, Moscow University and Dalton Ice Shelves, based on the Regional Oceanic Modeling System for the period 1992–2007. Simulated area-averaged basal melt rates (net basal mass loss) for the Totten and Dalton ice shelves are 9.1 m ice yr−1 (44.5 Gt ice yr−1) and 10.1 m ice yr−1 (46.6 Gt ice yr−1), respectively. The melting of the ice shelves varies strongly on seasonal and interannual timescales. Basal melting (mass loss) from the Totten ice shelf spans a range of 5.7 m ice yr−1 (28 Gt ice yr−1) on interannual timescales and 3.4 m ice yr−1 (17 Gt ice yr−1) on seasonal timescales. This study links basal melt of the Totten and Dalton ice shelves to warm water intrusions across the continental shelf break and atmosphere-ocean heat exchange. Totten ice shelf melting is high when the nearby Dalton polynya interannual strength is below average, and vice versa. Melting of the Dalton ice shelf is primarily controlled by the strength of warm water intrusions across the Dalton Rise and into the ice shelf cavity. During periods of strong westwards coastal current flow, Dalton melt water flows directly under the Totten ice shelf further reducing melting. This is the first such modelling study of this region, providing a valuable framework for directing future observational and modelling efforts.

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Sutherland, D. A., R. H. Jackson, C. Kienholz, J. M. Amundson, W. P. Dryer, D. Duncan, E. F. Eidam, R. J. Motyka, and J. D. Nash. "Direct observations of submarine melt and subsurface geometry at a tidewater glacier." Science 365, no. 6451 (July 25, 2019): 369–74. http://dx.doi.org/10.1126/science.aax3528.

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Ice loss from the world’s glaciers and ice sheets contributes to sea level rise, influences ocean circulation, and affects ecosystem productivity. Ongoing changes in glaciers and ice sheets are driven by submarine melting and iceberg calving from tidewater glacier margins. However, predictions of glacier change largely rest on unconstrained theory for submarine melting. Here, we use repeat multibeam sonar surveys to image a subsurface tidewater glacier face and document a time-variable, three-dimensional geometry linked to melting and calving patterns. Submarine melt rates are high across the entire ice face over both seasons surveyed and increase from spring to summer. The observed melt rates are up to two orders of magnitude greater than predicted by theory, challenging current simulations of ice loss from tidewater glaciers.

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Karaman, V. M., V. F. Shumsky, E. G. Privalko, V. P. Privalko, B. Lehmann, and K. Friedrich. "Melt Viscoelasticity of Polyamide 6/Organoclay Nanocomposites." Polymers and Polymer Composites 11, no. 8 (November 2003): 663–68. http://dx.doi.org/10.1177/096739110301100805.

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Commercial nanocomposites of polyamide 6, prepared by melt compounding with organoclay hybrids, were characterized by complex viscosities and relaxation time spectra derived from storage and loss shear moduli measured in the melt state at 230°C in the frequency window spanning about three decades. The results were rationalized in terms of the following model considerations. The decrease of ~25% (compared to the pristine sample) in Newtonian viscosity at the lowest clay loading (2.5%) suggested a lower equilibrium elasticity modulus of an entangled melt, as if the small amounts of organoclay nanoparticles acted as specific “diluents” for the initial entanglement network. However, at increasing clay contents this effect was apparently taken over by the ever growing importance of strong interactions at the nanoparticle/melt interface, leading to the formation of a fairly thick boundary interphase (BI) around the nanoparticles and, eventually, ending up in the build-up of an “infinite cluster” of clay nanoparticles coated with BI at the highest (albeit still unusually low) clay loading (7.5%).

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Hernández-Montenegro, David, Christopher L. Andronicos, Carlos A. Zuluaga, and Ruth F. Aronoff. "Effects of melt loss, melt retention, and protolith composition on differentiation of anatectic metapelites: A case study of the Wet Mountains, Colorado." Lithos 344-345 (November 2019): 425–39. http://dx.doi.org/10.1016/j.lithos.2019.06.032.

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Zapletalova, Terezie, Stephen Michielsen, and Behnam Pourdeyhimi. "Polyether Based Thermoplastic Polyurethane Melt Blown Nonwovens." Journal of Engineered Fibers and Fabrics 1, no. 1 (March 2006): 155892500600100. http://dx.doi.org/10.1177/155892500600100105.

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A series of melt blown samples were produced from three hardness grades of ether based thermoplastic polyurethane elastomers (TPU). The fabrics were tested to investigate their structure-property relationship in a melt blown process. Solution viscosities of the web were only 20–26% of there original values indicating a large loss in polymer molecular weight during melt blowing. Fiber diameter distributions measured on melt blown samples were found comparable to those made with more conventional polymers. The fiber orientation distribution functions (ODF) suggest slight fiber orientation in machine direction. Tensile and elongation properties depended on die-to-collector distance (DCD), polymer hardness and fiber ODF. A strong relationship between the tensile strength and die-to-collector distance was identified and attributed to reduced interfiber adhesion in the web with increasing DCD. The reduction in adhesion was attributed to greater extents of solidification before reaching the forming belt for longer DCDs. This paper is the first in a series relating the influence of the melt blowing process parameters on the polymer properties and the nonwoven fabric properties for block thermoplastic elastomers.

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Dunse, T., T. Schellenberger, J. O. Hagen, A. Kääb, T. V. Schuler, and C. H. Reijmer. "Glacier-surge mechanisms promoted by a hydro-thermodynamic feedback to summer melt." Cryosphere 9, no. 1 (February 5, 2015): 197–215. http://dx.doi.org/10.5194/tc-9-197-2015.

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Abstract. Mass loss from glaciers and ice sheets currently accounts for two-thirds of the observed global sea-level rise and has accelerated since the 1990s, coincident with strong atmospheric warming in the polar regions. Here we present continuous GPS measurements and satellite synthetic-aperture-radar-based velocity maps from Basin-3, the largest drainage basin of the Austfonna ice cap, Svalbard. Our observations demonstrate strong links between surface-melt and multiannual ice-flow acceleration. We identify a hydro-thermodynamic feedback that successively mobilizes stagnant ice regions, initially frozen to their bed, thereby facilitating fast basal motion over an expanding area. By autumn 2012, successive destabilization of the marine terminus escalated in a surge of Basin-3. The resulting iceberg discharge of 4.2±1.6 Gt a−1 over the period April 2012 to May 2013 triples the calving loss from the entire ice cap. With the seawater displacement by the terminus advance accounted for, the related sea-level rise contribution amounts to 7.2±2.6 Gt a−1. This rate matches the annual ice-mass loss from the entire Svalbard archipelago over the period 2003–2008, highlighting the importance of dynamic mass loss for glacier mass balance and sea-level rise. The active role of surface melt, i.e. external forcing, contrasts with previous views of glacier surges as purely internal dynamic instabilities. Given sustained climatic warming and rising significance of surface melt, we propose a potential impact of the hydro-thermodynamic feedback on the future stability of ice-sheet regions, namely at the presence of a cold-based marginal ice plug that restricts fast drainage of inland ice. The possibility of large-scale dynamic instabilities such as the partial disintegration of ice sheets is acknowledged but not quantified in global projections of sea-level rise.

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Mordret, Aurélien, T. Dylan Mikesell, Christopher Harig, Bradley P. Lipovsky, and Germán A. Prieto. "Monitoring southwest Greenland’s ice sheet melt with ambient seismic noise." Science Advances 2, no. 5 (May 2016): e1501538. http://dx.doi.org/10.1126/sciadv.1501538.

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The Greenland ice sheet presently accounts for ~70% of global ice sheet mass loss. Because this mass loss is associated with sea-level rise at a rate of 0.7 mm/year, the development of improved monitoring techniques to observe ongoing changes in ice sheet mass balance is of paramount concern. Spaceborne mass balance techniques are commonly used; however, they are inadequate for many purposes because of their low spatial and/or temporal resolution. We demonstrate that small variations in seismic wave speed in Earth’s crust, as measured with the correlation of seismic noise, may be used to infer seasonal ice sheet mass balance. Seasonal loading and unloading of glacial mass induces strain in the crust, and these strains then result in seismic velocity changes due to poroelastic processes. Our method provides a new and independent way of monitoring (in near real time) ice sheet mass balance, yielding new constraints on ice sheet evolution and its contribution to global sea-level changes. An increased number of seismic stations in the vicinity of ice sheets will enhance our ability to create detailed space-time records of ice mass variations.

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Röhl, Katrin. "Characteristics and evolution of supraglacial ponds on debris-covered Tasman Glacier, New Zealand." Journal of Glaciology 54, no. 188 (2008): 867–80. http://dx.doi.org/10.3189/002214308787779861.

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AbstractSupraglacial ponds on Tasman Glacier, New Zealand, initiated the development of the large Tasman Lake during the 1980s and still play an important role for ice loss and further terminus disintegration. Limnological and glaciological measurements between 2001 and 2003 reveal distinct differences between ponds. The hydraulic connection of a pond to the englacial water level exerts a key control on whether the pond contributes to longer-term terminus disintegration. In the earlier stages of pond development, ice loss occurs predominantly in the horizontal dimension by subaerial melt. Subaqueous calving at later stages plays a major role for ice loss. During the capture of a pond by the lake, substantial limnological changes lead to changes in relative significance and rates of ice loss processes, the most important being the change from melting to predominantly calving. As a result, ice loss accelerated from around 11 m a−1 of melt under partial debris cover to a retreat by calving and melting of 34 m a−1. Ice loss at the ponds accounted for only 10% of the surface loss in the lower terminus area, but is likely to increase in the future with enlargement and coalescence of ponds.

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Liu, Yan, John C. Moore, Xiao Cheng, Rupert M. Gladstone, Jeremy N. Bassis, Hongxing Liu, Jiahong Wen, and Fengming Hui. "Ocean-driven thinning enhances iceberg calving and retreat of Antarctic ice shelves." Proceedings of the National Academy of Sciences 112, no. 11 (March 2, 2015): 3263–68. http://dx.doi.org/10.1073/pnas.1415137112.

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Iceberg calving from all Antarctic ice shelves has never been directly measured, despite playing a crucial role in ice sheet mass balance. Rapid changes to iceberg calving naturally arise from the sporadic detachment of large tabular bergs but can also be triggered by climate forcing. Here we provide a direct empirical estimate of mass loss due to iceberg calving and melting from Antarctic ice shelves. We find that between 2005 and 2011, the total mass loss due to iceberg calving of 755 ± 24 gigatonnes per year (Gt/y) is only half the total loss due to basal melt of 1516 ± 106 Gt/y. However, we observe widespread retreat of ice shelves that are currently thinning. Net mass loss due to iceberg calving for these ice shelves (302 ± 27 Gt/y) is comparable in magnitude to net mass loss due to basal melt (312 ± 14 Gt/y). Moreover, we find that iceberg calving from these decaying ice shelves is dominated by frequent calving events, which are distinct from the less frequent detachment of isolated tabular icebergs associated with ice shelves in neutral or positive mass balance regimes. Our results suggest that thinning associated with ocean-driven increased basal melt can trigger increased iceberg calving, implying that iceberg calving may play an overlooked role in the demise of shrinking ice shelves, and is more sensitive to ocean forcing than expected from steady state calving estimates.

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Journal articles on the topic 'Melt loss'

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