scholarly journals Significant total mass contained in small glaciers

2012 ◽  
Vol 6 (1) ◽  
pp. 737-757
Author(s):  
D. B. Bahr ◽  
V. Radić
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Total Mass ◽  
Complete List ◽  
Ice Caps ◽  
Ice Volume ◽  
Regional Estimates ◽  
Source Of Error

Abstract. A single large glacier can contain hundreds of millions of times the mass of a small glacier. Nevertheless, small glaciers are so numerous that their contribution to the world's total ice volume is significant and may be a notable source of error if excluded. With current glacier inventories, total volume errors on the order of 10 % are possible at both global and regional scales. However, errors of less than 1 % require glaciers that are smaller than those available in some inventories. Such accuracy requires a global list of all glaciers and ice caps (GIC) as small as 1 km2, and for regional estimates requires substantially smaller sizes. For some regions, volume errors of less than 5 % require a complete list of all glaciers down to the smallest conceivable sizes. For this reason, sea-level rise estimates and other total mass and total volume analyses cannot ignore the world's smallest glaciers without careful justification.

scholarly journals Significant contribution to total mass from very small glaciers

2012 ◽  
Vol 6 (4) ◽  
pp. 763-770 ◽  
Author(s):  
D. B. Bahr ◽  
V. Radić
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Total Mass ◽  
Significant Contribution ◽  
Ice Sheets ◽  
Global Scale ◽  
Ice Caps ◽  
Ice Volume ◽  
Regional Estimates ◽  
Source Of Error

Abstract. A single large glacier can contain tens of millions of times the mass of a small glacier. Nevertheless, very small glaciers (with area ≤1 km2) are so numerous that their contribution to the world's total ice volume is significant and may be a notable source of error if excluded. With current glacier inventories, total global volume errors on the order of 10% are possible. However, to reduce errors to below 1% requires the inclusion of glaciers that are smaller than those recorded in most inventories. At the global scale, 1% accuracy requires a list of all glaciers and ice caps (GIC, exclusive of the ice sheets) larger than 1 km2, and for regional estimates requires a complete list of all glaciers down to the smallest possible size. For this reason, sea-level rise estimates and other total mass and total volume analyses should not omit the world's smallest glaciers. In particular, upscaling GIC inventories has been common practice in sea level estimates, but downscaling may also be necessary to include the smallest glaciers.

scholarly journals Brief communication "Global glacier volumes and sea level – small but systematic effects of ice below the surface of the ocean and of new local lakes on land"

2013 ◽  
Vol 7 (3) ◽  
pp. 817-821 ◽  
Author(s):  
W. Haeberli ◽  
A. Linsbauer
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Magnitude Estimate ◽  
Potential Contribution ◽  
Present Communication ◽  
First Order ◽  
Ice Caps ◽  
Ice Volume ◽  
Systematic Effects ◽  
Order Of Magnitude

Abstract. The potential contribution of glaciers and ice caps to sea level rise is usually calculated by comparing the estimated total ice volume with the surface area of the ocean. Part of this total ice volume, however, does not contribute to sea level rise because it is below the surface of the ocean or below the levels of future lakes on land. The present communication points to this so far overlooked phenomenon and provides a first order-of-magnitude estimate. It is shown that the effect is small (most likely about 1 to 6 cm sea level equivalent) but systematic, could primarily affect earlier stages of global glacier vanishing, and should therefore be adequately considered. Now-available techniques of slope-related high-resolution glacier bed modelling have the potential to provide more detailed assessments in the future.

scholarly journals Global glacier volumes and sea level – effects of ice below the surface of the ocean and of new local lakes on land

2012 ◽  
Vol 6 (6) ◽  
pp. 5169-5179
Author(s):  
W. Haeberli ◽  
A. Linsbauer
Keyword(s):  
High Resolution ◽  
Sea Level Rise ◽  
Sea Level ◽  
Magnitude Estimate ◽  
Potential Contribution ◽  
Present Communication ◽  
First Order ◽  
Ice Caps ◽  
Ice Volume ◽  
Order Of Magnitude

Abstract. The potential contribution of glaciers and ice caps to sea level rise is usually calculated by comparing the estimated total ice volume with the surface area of the ocean. Part of this total ice volume, however, does not contribute to sea-level rise, because it is below the surface of the ocean or below the levels of future lakes on land. The present communication points to this so far overlooked phenomenon and provides a first order-of-magnitude estimate. It is shown that the effect is small (most likely 1 to 5 cm sea-level equivalent) but systematic, could primarily affect earlier stages of global glacier vanishing and should therefore be adequately considered. Now-available techniques of slope-related high-resolution glacier-bed modelling have the potential to provide more detailed assessments in the future.

scholarly journals Mountain glaciers and ice caps around Antarctica make a large sea-level rise contribution

2009 ◽  
Vol 36 (7) ◽  
pp. n/a-n/a ◽  
Author(s):  
Regine Hock ◽  
Mattias de Woul ◽  
Valentina Radić ◽  
Mark Dyurgerov
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Ice Caps ◽  
Mountain Glaciers

scholarly journals Brief communication: On calculating the sea-level contribution in marine ice-sheet models

2020 ◽  
Vol 14 (3) ◽  
pp. 833-840 ◽  
Author(s):  
Heiko Goelzer ◽  
Violaine Coulon ◽  
Frank Pattyn ◽  
Bas de Boer ◽  
Roderik van de Wal
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Ice Sheets ◽  
Ice Sheet ◽  
Ocean Water ◽  
Ice Volume ◽  
Isostatic Adjustment ◽  
The Common

Abstract. Estimating the contribution of marine ice sheets to sea-level rise is complicated by ice grounded below sea level that is replaced by ocean water when melted. The common approach is to only consider the ice volume above floatation, defined as the volume of ice to be removed from an ice column to become afloat. With isostatic adjustment of the bedrock and external sea-level forcing that is not a result of mass changes of the ice sheet under consideration, this approach breaks down, because ice volume above floatation can be modified without actual changes in the sea-level contribution. We discuss a consistent and generalised approach for estimating the sea-level contribution from marine ice sheets.

scholarly journals The future sea-level rise contribution of Greenland’s glaciers and ice caps

2013 ◽  
Vol 8 (2) ◽  
pp. 025005 ◽  
Author(s):  
H Machguth ◽  
P Rastner ◽  
T Bolch ◽  
N Mölg ◽  
L Sandberg Sørensen ◽  
...  
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Ice Caps ◽  
The Future

Volume–area scaling parameterisation of Norwegian ice caps: A comparison of different approaches

The Holocene ◽  
2016 ◽  
Vol 27 (1) ◽  
pp. 164-171 ◽  
Author(s):  
Tron Laumann ◽  
Atle Nesje
Keyword(s):  
Water Resources ◽  
Sea Level Rise ◽  
Sea Level ◽  
Sea Level Change ◽  
Global Scale ◽  
Two Dimensional ◽  
Ice Caps ◽  
Level Change ◽  
Global Sea Level ◽  
Best Fit

Over the recent decades, glaciers have in general continued to lose mass, causing surface lowering, volume reduction and frontal retreat, thus contributing to global sea-level rise. When making assessments of present and future sea-level change and management of water resources in glaciated catchments, precise estimates of glacier volume are important. The glacier volume cannot be measured on every single glacier. Therefore, the global glacier volume must be estimated from models or scaling approaches. Volume–area scaling is mostly applied for estimating volumes of glaciers and ice caps on a regional and global scale by using a statistical–theoretical relationship between glacier volume ( V) and area ( A) ( V =  cAγ) (for explanation of the parameters c and γ, see Eq. 1). In this paper, a two-dimensional (2D) glacier model has been applied on four Norwegian ice caps (Hardangerjøkulen, Nordre Folgefonna, Spørteggbreen and Vestre Svartisen) in order to obtain values for the volume–area relationship on ice caps. The curve obtained for valley glaciers gives the best fit to the smallest plateau glaciers when c = 0.027 km3−2 γ and γ = 1.375, and a slightly poorer fit when the glacier increases in size. For ice caps, c = 0.056 km3−2 γ and γ = 1.25 fit reasonably well for the largest, but yield less fit to the smaller.

Recent contributions of glaciers and ice caps to sea level rise

Nature ◽  
2012 ◽  
Vol 482 (7386) ◽  
pp. 514-518 ◽  
Author(s):  
Thomas Jacob ◽  
John Wahr ◽  
W. Tad Pfeffer ◽  
Sean Swenson
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Ice Caps

Reassessing global ice volume: uncertainty and structure in sea level records

2021 ◽  
Author(s):  
Fiona D. Hibbert ◽  
Felicity Williams ◽  
Eelco Rohling
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Full Range ◽  
Ice Sheets ◽  
Change Point Analysis ◽  
Last Deglaciation ◽  
Ice Volume ◽  
Global Ice Volume ◽  
Modern Analogue ◽  
The Last Deglaciation

<p>Geologically recorded sea-level variations represent the sum total of all contributing processes, be it known or unknown, and may thus help in finding the full range of future sea-level rise. Significant sea-level-rise contributions from both northern and southern ice sheets are not unprecedented in the geological record and offer a well-constrained range of natural scenarios from intervals during which ice volumes were similar to or smaller than present (i.e., interglacial periods), to intervals during which total ice volume was greater (i.e., glacial periods).</p><p>The last deglaciation is the most recent period of widespread destabilisation and collapse of major continental ice sheets. Records spanning the last deglaciation (as well as the ice volume maxima) are few, fragmentary and seemingly inconsistent (e.g., the timing and magnitude of melt-water pulses), in part due to locational (tectonic and glacio-isostatic) as well as modern analogue considerations (e.g., palaeo-water depth or facies formation depth). We present a new synthesis of sea-level indicators, with particular emphasis on the geological and biological context, as well as the uncertainties of each record. Using this new compilation and the novel application of statistical methods (trans-dimensional change-point analysis, which avoids “overfitting” of noise in the data), we will assess global ice-volume changes, sea-level fluctuations and changes in climate during the last deglaciation. Finally, we discuss the implications of these uncertainties on our ability to constrain past cryosphere changes.</p>

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