Global ocean mass variation, continental hydrology and the mass balance of Antarctica Ice Sheet at seasonal time scale

Many recent mass balance estimates using the Gravity Recovery and Climate Experiment (GRACE) and satellite altimetry (including two kinds of sensors of radar and laser) show that the ice mass of the Antarctic ice sheet (AIS) is in overall decline. However, there are still large differences among previously published estimates of the total mass change, even in the same observed periods. The considerable error sources mainly arise from the forward models (e.g., glacial isostatic adjustment [GIA] and firn compaction) that may be uncertain but indispensable to simulate some processes not directly measured or obtained by these observations. To minimize the use of these forward models, we estimate the mass change of ice sheet and present-day GIA using multi-geodetic observations, including GRACE and Ice, Cloud and land Elevation Satellite (ICESat), as well as Global Positioning System (GPS), by an improved method of joint inversion estimate (JIE), which enables us to solve simultaneously for the Antarctic GIA and ice mass trends. The GIA uplift rates generated from our JIE method show a good agreement with the elastic-corrected GPS uplift rates, and the total GIA-induced mass change estimate for the AIS is 54 ± 27 Gt/yr, which is in line with many recent GPS calibrated GIA estimates. Our GIA result displays the presence of significant uplift rates in the Amundsen Sea Embayment of West Antarctica, where strong uplift has been observed by GPS. Over the period February 2003 to October 2009, the entire AIS changed in mass by −84 ± 31 Gt/yr (West Antarctica: −69 ± 24, East Antarctica: 12 ± 16 and the Antarctic Peninsula: −27 ± 8), greater than the GRACE-only estimates obtained from three Mascon solutions (CSR: −50 ± 30, JPL: −71 ± 30, and GSFC: −51 ± 33 Gt/yr) for the same period. This may imply that single GRACE data tend to underestimate ice mass loss due to the signal leakage and attenuation errors of ice discharge are often worse than that of surface mass balance over the AIS.

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Contemporary (1960–2012) Evolution of the Climate and Surface Mass Balance of the Greenland Ice Sheet

Surveys in Geophysics ◽

10.1007/s10712-013-9261-z ◽

2013 ◽

Vol 35 (5) ◽

pp. 1155-1174 ◽

Cited By ~ 73

Author(s):

J. H. van Angelen ◽

M. R. van den Broeke ◽

B. Wouters ◽

J. T. M. Lenaerts

Keyword(s):

Mass Balance ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Surface Mass Balance ◽

Surface Mass

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Greenland ice sheet mass balance: a review

Reports on Progress in Physics ◽

10.1088/0034-4885/78/4/046801 ◽

2015 ◽

Vol 78 (4) ◽

pp. 046801 ◽

Cited By ~ 85

Author(s):

Shfaqat A Khan ◽

Andy Aschwanden ◽

Anders A Bjørk ◽

John Wahr ◽

Kristian K Kjeldsen ◽

...

Keyword(s):

Mass Balance ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Ice Sheet Mass Balance

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On the characterization of glacier response by a single time-scale

Journal of Glaciology ◽

10.3189/172756501781831837 ◽

2001 ◽

Vol 47 (159) ◽

pp. 659-664 ◽

Cited By ~ 57

Author(s):

W. D. Harrison ◽

D. H. Elsberg ◽

K. A. Echelmeyer ◽

R. M. Krimmel

Keyword(s):

Climate Change ◽

Mass Balance ◽

Time Constant ◽

Time Scale ◽

Response Models ◽

Single Time ◽

Glacier Changes ◽

Major Increase ◽

Effect Of Surface

AbstractGlacier response to climate can be characterized by a single time-scale when the glacier changes sufficiently slowly. Then the derivative of volume with respect to area defines a thickness scale similar to that of Jóhannesson and others, and the time-scale follows from it. Our version of the time-scale is different from theirs because it explicitly includes the effect of surface elevation on mass-balance rate, which can cause a major increase in the time-scale or even lead to unstable response. The time constant has a dual role, controlling both the rate and magnitude of response to a given climate change. Data from South Cascade Glacier, Washington, U.S.A., illustrate the ideas, some of the difficulty in obtaining accurate values for the thickness and time-scales, and the susceptibility of all response models to potentially large errors.

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Monitoring southwest Greenland’s ice sheet melt with ambient seismic noise

Science Advances ◽

10.1126/sciadv.1501538 ◽

2016 ◽

Vol 2 (5) ◽

pp. e1501538 ◽

Cited By ~ 39

Author(s):

Aurélien Mordret ◽

T. Dylan Mikesell ◽

Christopher Harig ◽

Bradley P. Lipovsky ◽

Germán A. Prieto

Keyword(s):

Mass Loss ◽

Mass Balance ◽

Sea Level ◽

Seismic Noise ◽

Seismic Velocity ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Sea Level Changes ◽

Ice Sheet Mass Balance ◽

Velocity Changes

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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Mass Balance of the Greenland Ice Sheet at High Elevations

Science ◽

10.1126/science.289.5478.426 ◽

2000 ◽

Vol 289 (5478) ◽

pp. 426-428 ◽

Cited By ~ 69

Author(s):

R. Thomas

Keyword(s):

Mass Balance ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

High Elevations

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Simulation of the future sea level contribution of Greenland with a new glacial system model

The Cryosphere ◽

10.5194/tc-12-3097-2018 ◽

2018 ◽

Vol 12 (10) ◽

pp. 3097-3121 ◽

Cited By ~ 17

Author(s):

Reinhard Calov ◽

Sebastian Beyer ◽

Ralf Greve ◽

Johanna Beckmann ◽

Matteo Willeit ◽

...

Keyword(s):

Boundary Conditions ◽

Surface Temperature ◽

Mass Balance ◽

Sea Level Rise ◽

Sea Level ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

System Model ◽

Surface Mass Balance ◽

Surface Mass

Abstract. We introduce the coupled model of the Greenland glacial system IGLOO 1.0, including the polythermal ice sheet model SICOPOLIS (version 3.3) with hybrid dynamics, the model of basal hydrology HYDRO and a parameterization of submarine melt for marine-terminated outlet glaciers. The aim of this glacial system model is to gain a better understanding of the processes important for the future contribution of the Greenland ice sheet to sea level rise under future climate change scenarios. The ice sheet is initialized via a relaxation towards observed surface elevation, imposing the palaeo-surface temperature over the last glacial cycle. As a present-day reference, we use the 1961–1990 standard climatology derived from simulations of the regional atmosphere model MAR with ERA reanalysis boundary conditions. For the palaeo-part of the spin-up, we add the temperature anomaly derived from the GRIP ice core to the years 1961–1990 average surface temperature field. For our projections, we apply surface temperature and surface mass balance anomalies derived from RCP 4.5 and RCP 8.5 scenarios created by MAR with boundary conditions from simulations with three CMIP5 models. The hybrid ice sheet model is fully coupled with the model of basal hydrology. With this model and the MAR scenarios, we perform simulations to estimate the contribution of the Greenland ice sheet to future sea level rise until the end of the 21st and 23rd centuries. Further on, the impact of elevation–surface mass balance feedback, introduced via the MAR data, on future sea level rise is inspected. In our projections, we found the Greenland ice sheet to contribute between 1.9 and 13.0 cm to global sea level rise until the year 2100 and between 3.5 and 76.4 cm until the year 2300, including our simulated additional sea level rise due to elevation–surface mass balance feedback. Translated into additional sea level rise, the strength of this feedback in the year 2100 varies from 0.4 to 1.7 cm, and in the year 2300 it ranges from 1.7 to 21.8 cm. Additionally, taking the Helheim and Store glaciers as examples, we investigate the role of ocean warming and surface runoff change for the melting of outlet glaciers. It shows that ocean temperature and subglacial discharge are about equally important for the melting of the examined outlet glaciers.

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