Sequence stratigraphy, micropaleontology, and foraminiferal geochemistry, Bass River, New Jersey paleoshelf, USA: Implications for Eocene ice-volume changes

Abstract. Antarctic ice volume has varied substantially during the late Quaternary, with reconstructions suggesting a glacial ice sheet extending to the continental shelf break and interglacial sea level highstands of several meters. Throughout this period, changes in the Antarctic Ice Sheet were driven by changes in atmospheric and oceanic conditions and global sea level; yet, so far modeling studies have not addressed which of these environmental forcings dominate and how they interact in the dynamical ice sheet response. Here, we force an Antarctic Ice Sheet model with global sea level reconstructions and transient, spatially explicit boundary conditions from a 408 ka climate model simulation, not only in concert with each other but, for the first time, also separately. We find that together these forcings drive glacial–interglacial ice volume changes of 12–14 ms.l.e., in line with reconstructions and previous modeling studies. None of the individual drivers – atmospheric temperature and precipitation, ocean temperatures, or sea level – single-handedly explains the full ice sheet response. In fact, the sum of the individual ice volume changes amounts to less than half of the full ice volume response, indicating the existence of strong nonlinearities and forcing synergy. Both sea level and atmospheric forcing are necessary to create full glacial ice sheet growth, whereas the contribution of ocean melt changes is found to be more a function of ice sheet geometry than climatic change. Our results highlight the importance of accurately representing the relative timing of forcings of past ice sheet simulations and underscore the need for developing coupled climate–ice sheet modeling frameworks that properly capture key feedbacks.

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Ice volume changes (1936–1990–2007) and ground-penetrating radar studies of Ariebreen, Hornsund, Spitsbergen

Polar Research ◽

10.3402/polar.v32i0.11068 ◽

2013 ◽

Vol 32 (1) ◽

pp. 11068 ◽

Cited By ~ 8

Author(s):

Javier Lapazaran ◽

Michal Petlicki ◽

Francisco Navarro ◽

Francisco Machío ◽

Darek Puczko ◽

...

Keyword(s):

Ground Penetrating Radar ◽

Volume Changes ◽

Ice Volume ◽

Ground Penetrating

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Ice-volume changes of selected glaciers in the Swiss Alps since the end of the 19th century

Annals of Glaciology ◽

10.3189/172756407782871701 ◽

2007 ◽

Vol 46 ◽

pp. 145-149 ◽

Cited By ~ 105

Author(s):

Andreas Bauder ◽

Martin Funk ◽

Matthias Huss

Keyword(s):

19Th Century ◽

Temporal Variations ◽

Swiss Alps ◽

Ice Age ◽

Aerial Photographs ◽

Volume Changes ◽

Thickness Change ◽

Ice Volume ◽

The 1960S ◽

The 19Th Century

AbstractThe evolution of surface topography of glaciers in the Swiss Alps is well documented with high-resolution aerial photographs repeatedly recorded since the 1960s and further back in time with topographic maps including elevation contour lines first surveyed in the mid-19th century. In order to quantify and interpret glacier changes in the Swiss Alps, time series of volume changes over the last 100–150 years have been collected. The available datasets provide a detailed spatial resolution for the retreat period since the end of the Little Ice Age. The spatial distribution as well as temporal variations of the thickness change were analyzed. A significant ice loss since the end of the 19th century was observed in the ablation area, while the changes in the accumulation area were small. We found moderate negative secular rates until the 1960s, followed by steady to positive rates for about two decades and strong ice loss starting in the 1980s which has lasted until the present. An evaluation of 19 glaciers revealed a total ice volume loss of about 13km3 since the 1870s, of which 8.7 km3 occurred since the 1920s and 3.5 km3 since 1980. Decadal mean net balance rates for the periods 1920–60, 1960–80 and 1980–present are –0.29, –0.03 and –0.53ma–1w.e., respectively.

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A comparison of empirical and physically based glacier surface melt models for long-term simulations of glacier response

Journal of Glaciology ◽

10.3189/2014jog14j011 ◽

2014 ◽

Vol 60 (224) ◽

pp. 1140-1154 ◽

Cited By ~ 41

Author(s):

Jeannette Gabbi ◽

Marco Carenzo ◽

Francesca Pellicciotti ◽

Andreas Bauder ◽

Martin Funk

Keyword(s):

Shortwave Radiation ◽

Radiation Balance ◽

Volume Changes ◽

Glacier Surface ◽

Surface Evolution ◽

Ice Volume ◽

In Situ Data ◽

Physically Based

AbstractWe investigate the performance of five glacier melt models over a multi-decadal period in order to assess their ability to model future glacier response. The models range from a simple degree-day model, based solely on air temperature, to more-sophisticated models, including the full shortwave radiation balance. In addition to the empirical models, the performance of a physically based energy-balance (EB) model is examined. The melt models are coupled to an accumulation and a surface evolution model and applied in a distributed manner to Rhonegletscher, Switzerland, over the period 1929–2012 at hourly resolution. For calibration, seasonal mass-balance measurements (2006–12) are used. Decadal ice volume changes for six periods in the years 1929–2012 serve for model validation. Over the period 2006–12, there are almost no differences in performance between the models, except for EB, which is less consistent with observations, likely due to lack of meteorological in situ data. However, simulations over the long term (1929–2012) reveal that models which include a separate term for shortwave radiation agree best with the observed ice volume changes, indicating that their melt relationships are robust in time and thus suitable for long-term modelling, in contrast to more empirical approaches that are oversensitive to temperature fluctuations.

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An upper-bound estimate for the accuracy of volume-area scaling

The Cryosphere Discussions ◽

10.5194/tcd-7-2293-2013 ◽

2013 ◽

Vol 7 (3) ◽

pp. 2293-2331 ◽

Cited By ~ 1

Author(s):

D. Farinotti ◽

M. Huss

Keyword(s):

Volume Change ◽

Upper Bound ◽

Synthetic Data ◽

Volume Changes ◽

Real World Data ◽

Secondary Importance ◽

Ice Volume ◽

Volume Measurements ◽

Upper Bound Estimate ◽

The Impact

Abstract. Volume-area scaling is the most popular method for estimating the ice volume of large glacier samples. Here, a series of resampling experiments based on different sets of synthetic data are presented in order to derive an upper-bound estimate (i.e. a level achieved only with ideal conditions) for the accuracy of its application. We also quantify the maximum accuracy expected when scaling is used for determining the glacier volume change, and area change of a given glacier population. A comprehensive set of measured glacier areas, volumes, area and volume changes is evaluated to investigate the impact of real-world data quality on the so assessed accuracies. For populations larger than a few thousand glaciers, the total ice volume can be recovered within 30% if all measurements available worldwide are used for estimating the scaling coefficients. Assuming no systematic biases in ice volume measurements, their uncertainty is of secondary importance. Knowing the individual areas of a glacier sample for two points in time allows recovering the corresponding ice volume change within 40% for populations larger than a few hundred glaciers, both for steady-state and transient geometries. If ice volume changes can be estimated without bias, glacier area changes derived from volume-area scaling show similar uncertainties as for the volume changes. This paper does not aim at making a final judgement about the suitability of volume-area scaling, but provides the means for assessing the accuracy expected from its application.

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