Density assumptions for converting geodetic glacier volume change to mass change
The geodetic method is widely used for assessing changes in the mass balance of mountain glaciers. However, comparison of repeated digital elevation models only provides a glacier volume change that must be converted to a change in mass using a density assumption or model. This study investigates th...
Published in: | The Cryosphere |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2013
|
Subjects: | |
Online Access: | https://doi.org/10.5194/tc-7-877-2013 http://www.the-cryosphere.net/7/877/2013/tc-7-877-2013.pdf https://doaj.org/article/1fcc44f8429d45cfbb378c2b8453964f |
id |
fttriple:oai:gotriple.eu:oai:doaj.org/article:1fcc44f8429d45cfbb378c2b8453964f |
---|---|
record_format |
openpolar |
spelling |
fttriple:oai:gotriple.eu:oai:doaj.org/article:1fcc44f8429d45cfbb378c2b8453964f 2023-05-15T18:32:22+02:00 Density assumptions for converting geodetic glacier volume change to mass change M. Huss 2013-05-01 https://doi.org/10.5194/tc-7-877-2013 http://www.the-cryosphere.net/7/877/2013/tc-7-877-2013.pdf https://doaj.org/article/1fcc44f8429d45cfbb378c2b8453964f en eng Copernicus Publications doi:10.5194/tc-7-877-2013 1994-0416 1994-0424 http://www.the-cryosphere.net/7/877/2013/tc-7-877-2013.pdf https://doaj.org/article/1fcc44f8429d45cfbb378c2b8453964f undefined The Cryosphere, Vol 7, Iss 3, Pp 877-887 (2013) geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2013 fttriple https://doi.org/10.5194/tc-7-877-2013 2023-01-22T18:50:39Z The geodetic method is widely used for assessing changes in the mass balance of mountain glaciers. However, comparison of repeated digital elevation models only provides a glacier volume change that must be converted to a change in mass using a density assumption or model. This study investigates the use of a constant factor for the volume-to-mass conversion based on a firn compaction model applied to simplified glacier geometries with idealized climate forcing, and two glaciers with long-term mass balance series. It is shown that the "density" of geodetic volume change is not a constant factor and is systematically smaller than ice density in most cases. This is explained by the accretion/removal of low-density firn layers, and changes in the firn density profile with positive/negative mass balance. Assuming a value of 850 ± 60 kg m−3 to convert volume change to mass change is appropriate for a wide range of conditions. For short time intervals (≤3 yr), periods with limited volume change, and/or changing mass balance gradients, the conversion factor can however vary from 0–2000 kg m−3 and beyond, which requires caution when interpreting glacier mass changes based on geodetic surveys. Article in Journal/Newspaper The Cryosphere Unknown Geodetic Glacier ENVELOPE(163.800,163.800,-77.750,-77.750) The Cryosphere 7 3 877 887 |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
fttriple |
language |
English |
topic |
geo envir |
spellingShingle |
geo envir M. Huss Density assumptions for converting geodetic glacier volume change to mass change |
topic_facet |
geo envir |
description |
The geodetic method is widely used for assessing changes in the mass balance of mountain glaciers. However, comparison of repeated digital elevation models only provides a glacier volume change that must be converted to a change in mass using a density assumption or model. This study investigates the use of a constant factor for the volume-to-mass conversion based on a firn compaction model applied to simplified glacier geometries with idealized climate forcing, and two glaciers with long-term mass balance series. It is shown that the "density" of geodetic volume change is not a constant factor and is systematically smaller than ice density in most cases. This is explained by the accretion/removal of low-density firn layers, and changes in the firn density profile with positive/negative mass balance. Assuming a value of 850 ± 60 kg m−3 to convert volume change to mass change is appropriate for a wide range of conditions. For short time intervals (≤3 yr), periods with limited volume change, and/or changing mass balance gradients, the conversion factor can however vary from 0–2000 kg m−3 and beyond, which requires caution when interpreting glacier mass changes based on geodetic surveys. |
format |
Article in Journal/Newspaper |
author |
M. Huss |
author_facet |
M. Huss |
author_sort |
M. Huss |
title |
Density assumptions for converting geodetic glacier volume change to mass change |
title_short |
Density assumptions for converting geodetic glacier volume change to mass change |
title_full |
Density assumptions for converting geodetic glacier volume change to mass change |
title_fullStr |
Density assumptions for converting geodetic glacier volume change to mass change |
title_full_unstemmed |
Density assumptions for converting geodetic glacier volume change to mass change |
title_sort |
density assumptions for converting geodetic glacier volume change to mass change |
publisher |
Copernicus Publications |
publishDate |
2013 |
url |
https://doi.org/10.5194/tc-7-877-2013 http://www.the-cryosphere.net/7/877/2013/tc-7-877-2013.pdf https://doaj.org/article/1fcc44f8429d45cfbb378c2b8453964f |
long_lat |
ENVELOPE(163.800,163.800,-77.750,-77.750) |
geographic |
Geodetic Glacier |
geographic_facet |
Geodetic Glacier |
genre |
The Cryosphere |
genre_facet |
The Cryosphere |
op_source |
The Cryosphere, Vol 7, Iss 3, Pp 877-887 (2013) |
op_relation |
doi:10.5194/tc-7-877-2013 1994-0416 1994-0424 http://www.the-cryosphere.net/7/877/2013/tc-7-877-2013.pdf https://doaj.org/article/1fcc44f8429d45cfbb378c2b8453964f |
op_rights |
undefined |
op_doi |
https://doi.org/10.5194/tc-7-877-2013 |
container_title |
The Cryosphere |
container_volume |
7 |
container_issue |
3 |
container_start_page |
877 |
op_container_end_page |
887 |
_version_ |
1766216476957605888 |