Mapping the bathymetry of supraglacial lakes and streams on the Greenland ice sheet using field measurements and high-resolution satellite images
Recent melt events on the Greenland ice sheet (GrIS) accentuate the need to constrain estimates of sea level rise through improved characterization of meltwater pathways. This effort will require more precise estimates of the volume of water stored on the surface of the GrIS. We assessed the potenti...
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ftdoajarticles:oai:doaj.org/article:87e73e2474694ae593d550e8cc55a924 2023-05-15T16:28:28+02:00 Mapping the bathymetry of supraglacial lakes and streams on the Greenland ice sheet using field measurements and high-resolution satellite images C. J. Legleiter M. Tedesco L. C. Smith A. E. Behar B. T. Overstreet 2014-02-01T00:00:00Z https://doi.org/10.5194/tc-8-215-2014 https://doaj.org/article/87e73e2474694ae593d550e8cc55a924 EN eng Copernicus Publications http://www.the-cryosphere.net/8/215/2014/tc-8-215-2014.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-8-215-2014 https://doaj.org/article/87e73e2474694ae593d550e8cc55a924 The Cryosphere, Vol 8, Iss 1, Pp 215-228 (2014) Environmental sciences GE1-350 Geology QE1-996.5 article 2014 ftdoajarticles https://doi.org/10.5194/tc-8-215-2014 2022-12-30T23:42:41Z Recent melt events on the Greenland ice sheet (GrIS) accentuate the need to constrain estimates of sea level rise through improved characterization of meltwater pathways. This effort will require more precise estimates of the volume of water stored on the surface of the GrIS. We assessed the potential to obtain such information by mapping the bathymetry of supraglacial lakes and streams from WorldView2 (WV2) satellite images. Simultaneous in situ observations of depth and reflectance from two streams and a lake with measured depths up to 10.45 m were used to test a spectrally based depth retrieval algorithm. We performed optimal band ratio analysis (OBRA) of continuous field spectra and spectra convolved to the bands of the WV2, Landsat 7 (ETM+), MODIS, and ASTER sensors. The field spectra yielded a strong relationship with depth ( R 2 = 0.94), and OBRA R 2 values were nearly as high (0.87–0.92) for convolved spectra, suggesting that these sensors' broader bands would be sufficient for depth retrieval. Our field measurements thus indicated that remote sensing of supraglacial bathymetry is not only feasible but potentially highly accurate. OBRA of spectra from 2 m-pixel WV2 images acquired within 3–72 h of our field observations produced an optimal R 2 value of 0.92 and unbiased, precise depth estimates, with mean and root mean square errors < 1% and 10–25% of the mean depth. Bathymetric maps produced by applying OBRA relations revealed subtle features of lake and channel morphology. In addition to providing refined storage volume estimates for lakes of various sizes, this approach can help provide estimates of the transient flux of meltwater through streams. Article in Journal/Newspaper Greenland Ice Sheet The Cryosphere Directory of Open Access Journals: DOAJ Articles Greenland The Cryosphere 8 1 215 228 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 C. J. Legleiter M. Tedesco L. C. Smith A. E. Behar B. T. Overstreet Mapping the bathymetry of supraglacial lakes and streams on the Greenland ice sheet using field measurements and high-resolution satellite images |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Recent melt events on the Greenland ice sheet (GrIS) accentuate the need to constrain estimates of sea level rise through improved characterization of meltwater pathways. This effort will require more precise estimates of the volume of water stored on the surface of the GrIS. We assessed the potential to obtain such information by mapping the bathymetry of supraglacial lakes and streams from WorldView2 (WV2) satellite images. Simultaneous in situ observations of depth and reflectance from two streams and a lake with measured depths up to 10.45 m were used to test a spectrally based depth retrieval algorithm. We performed optimal band ratio analysis (OBRA) of continuous field spectra and spectra convolved to the bands of the WV2, Landsat 7 (ETM+), MODIS, and ASTER sensors. The field spectra yielded a strong relationship with depth ( R 2 = 0.94), and OBRA R 2 values were nearly as high (0.87–0.92) for convolved spectra, suggesting that these sensors' broader bands would be sufficient for depth retrieval. Our field measurements thus indicated that remote sensing of supraglacial bathymetry is not only feasible but potentially highly accurate. OBRA of spectra from 2 m-pixel WV2 images acquired within 3–72 h of our field observations produced an optimal R 2 value of 0.92 and unbiased, precise depth estimates, with mean and root mean square errors < 1% and 10–25% of the mean depth. Bathymetric maps produced by applying OBRA relations revealed subtle features of lake and channel morphology. In addition to providing refined storage volume estimates for lakes of various sizes, this approach can help provide estimates of the transient flux of meltwater through streams. |
format |
Article in Journal/Newspaper |
author |
C. J. Legleiter M. Tedesco L. C. Smith A. E. Behar B. T. Overstreet |
author_facet |
C. J. Legleiter M. Tedesco L. C. Smith A. E. Behar B. T. Overstreet |
author_sort |
C. J. Legleiter |
title |
Mapping the bathymetry of supraglacial lakes and streams on the Greenland ice sheet using field measurements and high-resolution satellite images |
title_short |
Mapping the bathymetry of supraglacial lakes and streams on the Greenland ice sheet using field measurements and high-resolution satellite images |
title_full |
Mapping the bathymetry of supraglacial lakes and streams on the Greenland ice sheet using field measurements and high-resolution satellite images |
title_fullStr |
Mapping the bathymetry of supraglacial lakes and streams on the Greenland ice sheet using field measurements and high-resolution satellite images |
title_full_unstemmed |
Mapping the bathymetry of supraglacial lakes and streams on the Greenland ice sheet using field measurements and high-resolution satellite images |
title_sort |
mapping the bathymetry of supraglacial lakes and streams on the greenland ice sheet using field measurements and high-resolution satellite images |
publisher |
Copernicus Publications |
publishDate |
2014 |
url |
https://doi.org/10.5194/tc-8-215-2014 https://doaj.org/article/87e73e2474694ae593d550e8cc55a924 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet The Cryosphere |
genre_facet |
Greenland Ice Sheet The Cryosphere |
op_source |
The Cryosphere, Vol 8, Iss 1, Pp 215-228 (2014) |
op_relation |
http://www.the-cryosphere.net/8/215/2014/tc-8-215-2014.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-8-215-2014 https://doaj.org/article/87e73e2474694ae593d550e8cc55a924 |
op_doi |
https://doi.org/10.5194/tc-8-215-2014 |
container_title |
The Cryosphere |
container_volume |
8 |
container_issue |
1 |
container_start_page |
215 |
op_container_end_page |
228 |
_version_ |
1766018125034160128 |