Ice genesis and its long-term dynamics in Scărişoara Ice Cave, Romania

Abstract. The paleoclimatic significance of the perennial ice deposit in Scărişoara Ice Cave has been remarked on since the early 20th century, but a lack of understanding of the processes involved in the genesis, age and long-term dynamics and volume fluctuations of ice hampered all attempts to extract valuable data on past climate and vegetation changes. In this paper, we present a model of ice genesis and dynamics, based on stable isotopes, ice level monitoring (modern and archived) and radiocarbon dating of organic matter found in the ice. Ice in this cave mostly consists of layers of lake ice, produced as liquid water freezes from top to bottom in mid-autumn, and floor ice, produced as inflow water in winter freezes on top of the lake ice. This mechanism was also acting in the past, during the Medieval Warm Period and the Little Ice Age. The ice block is not stable in shape and volume, being continuously modified by ablation on top and sides, basal melting and lateral flow. Radiocarbon dating shows that the ice block is older than 1000 years, but ice flow and differential basal melting suggesting that the ice could be much older.

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Snow accumulation and ice flow at Dôme du Goûter (4300 m), Mont Blanc, French Alps

Journal of Glaciology ◽

10.3189/s0022143000035127 ◽

1997 ◽

Vol 43 (145) ◽

pp. 513-521 ◽

Cited By ~ 2

Author(s):

C. Vincent ◽

M. Vallon ◽

J. F. Pinglot ◽

M. Funk ◽

L. Reynaud

Keyword(s):

Mass Balance ◽

Flow Model ◽

Snow Accumulation ◽

Ice Age ◽

Seasonal Patterns ◽

Ice Flow ◽

The Alps ◽

Radioactivity Measurements ◽

Simple Flow

AbstractGlaciological experiments have been carried out at Dôme du Goûter (4300 m a.s.l.), Mont Blanc, in order to understand the flow of firn/ice in this high-altitude Alpine glacierized area. Accumulation measurements from stakes show a very strong spatial variability and an unusual feature of mass-balance fluctuations for the Alps, i.e. the snow accumulation does not show any seasonal patterns. Measured vertical velocities which should match with long-term mean mass balance are consistent with observed accumulations. Therefore, the measurement of vertical velocities seems a good way of quickly obtaining reliable mean accumulation values for several decades in such a region.A simple flow model can be used to determine the main flowlines of the glacier and to propose snow/ice age of core samples from the two boreholes drilled down tο the bedrock in June 1994. These results coincide with radioactivity measurements made to identify the well-known radioactive snow layers of 1963 and 1986. We can hope to obtain ice samples 55–60 years old about 20 or 30 m above the bedrock (110 m deep). Below, the deformation of the ice layers is loo great to be dated accurately.

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Simulating the evolution of Hardangerjøkulen ice cap in southern Norway since the mid-Holocene and its sensitivity to climate change

The Cryosphere ◽

10.5194/tc-11-281-2017 ◽

2017 ◽

Vol 11 (1) ◽

pp. 281-302 ◽

Cited By ~ 11

Author(s):

Henning Åkesson ◽

Kerim H. Nisancioglu ◽

Rianne H. Giesen ◽

Mathieu Morlighem

Keyword(s):

Climate Change ◽

Mass Balance ◽

Ice Age ◽

Ice Flow ◽

Outlet Glacier ◽

Surface Mass ◽

Ice Caps ◽

Ice Cap ◽

Length Changes

Abstract. Understanding of long-term dynamics of glaciers and ice caps is vital to assess their recent and future changes, yet few long-term reconstructions using ice flow models exist. Here we present simulations of the maritime Hardangerjøkulen ice cap in Norway from the mid-Holocene through the Little Ice Age (LIA) to the present day, using a numerical ice flow model combined with glacier and climate reconstructions. In our simulation, under a linear climate forcing, we find that Hardangerjøkulen grows from ice-free conditions in the mid-Holocene to its maximum extent during the LIA in a nonlinear, spatially asynchronous fashion. During its fastest stage of growth (2300–1300 BP), the ice cap triples its volume in less than 1000 years. The modeled ice cap extent and outlet glacier length changes from the LIA until today agree well with available observations. Volume and area for Hardangerjøkulen and several of its outlet glaciers vary out-of-phase for several centuries during the Holocene. This volume–area disequilibrium varies in time and from one outlet glacier to the next, illustrating that linear relations between ice extent, volume and glacier proxy records, as generally used in paleoclimatic reconstructions, have only limited validity. We also show that the present-day ice cap is highly sensitive to surface mass balance changes and that the effect of the ice cap hypsometry on the mass balance–altitude feedback is essential to this sensitivity. A mass balance shift by +0.5 m w.e. relative to the mass balance from the last decades almost doubles ice volume, while a decrease of 0.2 m w.e. or more induces a strong mass balance–altitude feedback and makes Hardangerjøkulen disappear entirely. Furthermore, once disappeared, an additional +0.1 m w.e. relative to the present mass balance is needed to regrow the ice cap to its present-day extent. We expect that other ice caps with comparable geometry in, for example, Norway, Iceland, Patagonia and peripheral Greenland may behave similarly, making them particularly vulnerable to climate change.

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Snow accumulation and ice flow at Dôme du Goûter (4300 m), Mont Blanc, French Alps

Journal of Glaciology ◽

10.1017/s0022143000035127 ◽

1997 ◽

Vol 43 (145) ◽

pp. 513-521 ◽

Cited By ~ 41

Author(s):

C. Vincent ◽

M. Vallon ◽

J. F. Pinglot ◽

M. Funk ◽

L. Reynaud

Keyword(s):

Mass Balance ◽

Flow Model ◽

Snow Accumulation ◽

Ice Age ◽

Seasonal Patterns ◽

Ice Flow ◽

The Alps ◽

Radioactivity Measurements ◽

Simple Flow

AbstractGlaciological experiments have been carried out at Dôme du Goûter (4300 m a.s.l.), Mont Blanc, in order to understand the flow of firn/ice in this high-altitude Alpine glacierized area. Accumulation measurements from stakes show a very strong spatial variability and an unusual feature of mass-balance fluctuations for the Alps, i.e. the snow accumulation does not show any seasonal patterns. Measured vertical velocities which should match with long-term mean mass balance are consistent with observed accumulations. Therefore, the measurement of vertical velocities seems a good way of quickly obtaining reliable mean accumulation values for several decades in such a region.A simple flow model can be used to determine the main flowlines of the glacier and to propose snow/ice age of core samples from the two boreholes drilled down tο the bedrock in June 1994. These results coincide with radioactivity measurements made to identify the well-known radioactive snow layers of 1963 and 1986. We can hope to obtain ice samples 55–60 years old about 20 or 30 m above the bedrock (110 m deep). Below, the deformation of the ice layers is loo great to be dated accurately.

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Health and sustainability of glaciers in High Mountain Asia

Nature Communications ◽

10.1038/s41467-021-23073-4 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Evan Miles ◽

Michael McCarthy ◽

Amaury Dehecq ◽

Marin Kneib ◽

Stefan Fugger ◽

...

Keyword(s):

Current Knowledge ◽

Field Measurements ◽

Tien Shan ◽

High Mountain ◽

Specific Mass ◽

Ice Flow ◽

Ice Volume ◽

Mass Redistribution ◽

Glacier Ablation

AbstractGlaciers in High Mountain Asia generate meltwater that supports the water needs of 250 million people, but current knowledge of annual accumulation and ablation is limited to sparse field measurements biased in location and glacier size. Here, we present altitudinally-resolved specific mass balances (surface, internal, and basal combined) for 5527 glaciers in High Mountain Asia for 2000–2016, derived by correcting observed glacier thinning patterns for mass redistribution due to ice flow. We find that 41% of glaciers accumulated mass over less than 20% of their area, and only 60% ± 10% of regional annual ablation was compensated by accumulation. Even without 21st century warming, 21% ± 1% of ice volume will be lost by 2100 due to current climatic-geometric imbalance, representing a reduction in glacier ablation into rivers of 28% ± 1%. The ablation of glaciers in the Himalayas and Tien Shan was mostly unsustainable and ice volume in these regions will reduce by at least 30% by 2100. The most important and vulnerable glacier-fed river basins (Amu Darya, Indus, Syr Darya, Tarim Interior) were supplied with >50% sustainable glacier ablation but will see long-term reductions in ice mass and glacier meltwater supply regardless of the Karakoram Anomaly.

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Evaluating Simple Methodology for Piezoelectric Level Sensors Protection

Proceedings ◽

10.3390/ecws-4-06448 ◽

2019 ◽

Vol 48 (1) ◽

pp. 30

Author(s):

Luis Hamilton Pospissil Garbossa ◽

Argeu Vanz ◽

Matias Guilherme Boll ◽

Hamilton Justino Vieira

Keyword(s):

Water Level ◽

Flood Control ◽

Low Cost ◽

Solid Particles ◽

Storm Events ◽

Sewer Systems ◽

Continuous Monitor ◽

Level Monitoring ◽

Water Level Monitoring

The increasing frequency of extreme storm events has implications for the operation of sewer systems, storm water, flood control monitoring and tide level variations. Accurate and continuous monitor water level monitoring is demanded in different environments. Piezoelectric sensors are widely used for water level monitoring and work submerged in waters subject to the presence of solid particles, biological fouling and saltwater oxidation. This work aimed to develop a simple, low-cost methodology to protect sensors over long-term deployment. The results show that simple actions, costing less than 2 EUR, can protect and extend the lifecycle of equipment worth over 2000 EUR, ensuring continuous monitoring and maintaining quality measurements.

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Terms and conditions of high-mountain lake ice-cover chemistry (Carpathians, Poland)

Journal of Glaciology ◽

10.3189/2015jog15j045 ◽

2015 ◽

Vol 61 (230) ◽

pp. 1207-1212 ◽

Cited By ~ 1

Author(s):

Iwona Kurzyca ◽

Adam Choiński ◽

Joanna Pociask-Karteczka ◽

Agnieszka Lawniczak ◽

Marcin Frankowski

Keyword(s):

Water Body ◽

Ice Cover ◽

Multilayered Structure ◽

Mountain Lake ◽

High Mountain ◽

Lake Ice ◽

High Mountain Lake ◽

Spatial Diversification ◽

The Tatra Mountains

AbstractWe discuss the results of an investigation of the chemical composition of the ice cover on the high-mountain lake Morskie Oko in the Tatra Mountains, Carpathians, Poland. In the years 2007–13, the ice cover was characterized by an average duration of 6 months, a thickness range of 0.40–1.14 m, and a multilayered structure with water or slush inclusion. In water from the melted ice cover, chloride (max. 69%) and sulphate (max. 51%) anions and ammonium (max. 66%) and calcium (max. 78%) cations predominated. Different concentrations of ions (F−, Cl−, NO3−, SO42−, Na+, K+, Mg2+, Ca2+, NH4+) in the upper, middle and bottom layers of ice were observed, along with long-term variability and spatial diversification within the ice layer over the lake. Snowpack lying on the ice and the water body under the ice were also investigated, and the influence on the ice cover of certain ions in elevated concentrations was observed (e.g. Cl− in the upper ice cover and the snowpack, and Ca2+ in the bottom ice cover and water body).

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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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Ice processes and growth history on Arctic and sub-Arctic lakes using ERS-1 SAR data

Polar Record ◽

10.1017/s0032247400013619 ◽

1995 ◽

Vol 31 (177) ◽

pp. 115-128 ◽

Cited By ~ 53

Author(s):

K. Morris ◽

M. O. Jeffries ◽

W. F. Weeks

Keyword(s):

Arctic Lakes ◽

Polar Regions ◽

Lake Ice ◽

Sar Images ◽

The North ◽

Growth History ◽

North Slope Of Alaska ◽

Term Monitoring ◽

Selection Of

AbstractA survey of ice growth and decay processes on a selection of shallow and deep sub-Arctic and Arctic lakes was conducted using radiometrically calibrated ERS-1 SAR images. Time series of radar backscatter data were compiled for selected sites on the lakes during the period of ice cover (September to June) for the years 1991–92 and 1992–93. A variety of lake-ice processes could be observed, and significant changes in backscatter occurred from the time of initial ice formation in autumn until the onset of the spring thaw. Backscatter also varied according to the location and depth of the lakes. The spatial and temporal changes in backscatter were most constant and predictable at the shallow lakes on the North Slope of Alaska. As a consequence, they represent the most promising sites for long-term monitoring and the detection of changes related to global warming and its effects on the polar regions.

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Paleoclimatic Implications of Radiocarbon Dating Of Speleothems from the Cracow-Wieluń Upland, Southern Poland

Radiocarbon ◽

10.1017/s0033822200030538 ◽

1995 ◽

Vol 37 (2) ◽

pp. 103-110 ◽

Cited By ~ 18

Author(s):

Anna Pazdur ◽

Mieczysław F. Pazdur ◽

Jacek Pawlyta ◽

Andrzej Górny ◽

Michał Olszewski

Keyword(s):

Systematic Study ◽

Radiocarbon Dating ◽

Karst Region ◽

Radiocarbon Dates ◽

Preliminary Results ◽

Last Glaciation ◽

Geological Museum ◽

Paleoclimatic Records ◽

Age Range

We report preliminary results of a long-term systematic study intended to gather paleoclimatic records from precisely dated speleothems. The research project is limited to speleothems deposited in caves of the Cracow-Wieluń Upland, the largest and best-explored karst region in Poland, covering ca. 2900 km2 with >1000 caves. Speleothem samples were selected from collections of the Geological Museum of the Academy of Mining and Metallurgy in Cracow. Radiocarbon dates of these samples from ca. 45–20 ka bp almost exactly coincide with age range of the Interplenivistulian. A break in speleothem formation between ca. 20 and 10 ka bp may be interpreted as a result of serious climatic deterioration associated with the maximum extent of the last glaciation. We observed differences among 14C, U/Th and AAR dating results. Changes of δ13C and δ18O in speleothems that grew between ca. 30 and 20 ka bp may be interpreted as changes of paleoclimatic conditions.

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