---
_id: '12590'
abstract:
- lang: eng
  text: 'Ice cliffs play a key role in the mass balance of debris-covered glaciers,
    but assessing their importance is limited by a lack of datasets on their distribution
    and evolution at scales larger than an individual glacier. These datasets are
    often derived using operator-biased and time-consuming manual delineation approaches,
    despite the recent emergence of semi-automatic mapping methods. These methods
    have used elevation or multispectral data, but the varying slope and mixed spectral
    signal of these dynamic features makes the transferability of these approaches
    particularly challenging. We develop three semi-automated and objective new approaches,
    based on the Spectral Curvature and Linear Spectral Unmixing of multispectral
    images, to map these features at a glacier to regional scale. The transferability
    of each method is assessed by applying it to three sites in the Himalaya, where
    debris-covered glaciers are widespread, with varying lithologic, glaciological
    and climatic settings, and encompassing different periods of the melt season.
    We develop the new methods keeping in mind the wide range of remote sensing platforms
    currently in use, and focus in particular on two products: we apply the three
    approaches at each site to near-contemporaneous atmospherically-corrected Pléiades
    (2 m resolution) and Sentinel-2 (10 m resolution) images and assess the effects
    of spatial and spectral resolution on the results. We find that the Spectral Curvature
    method works best for the high spatial resolution, four band Pléaides images,
    while a modification of the Linear Spectral Unmixing using the scaling factor
    of the unmixing is best for the coarser spatial resolution, but additional spectral
    information of Sentinel-2 products. In both cases ice cliffs are mapped with a
    Dice coefficient higher than 0.48. Comparison of the Pléiades results with other
    existing methods shows that the Spectral Curvature approach performs better and
    is more robust than any other existing automated or semi-automated approaches.
    Both methods outline a high number of small, sometimes shallow-sloping and thinly
    debris-covered ice patches that differ from our traditional understanding of cliffs
    but may have non-negligible impact on the mass balance of debris-covered glaciers.
    Overall these results pave the way for large scale efforts of ice cliff mapping
    that can enable inclusion of these features in debris-covered glacier melt models,
    as well as allow the generation of multiple datasets to study processes of cliff
    formation, evolution and decline.'
article_number: '112201'
article_processing_charge: No
article_type: original
author:
- first_name: M.
  full_name: Kneib, M.
  last_name: Kneib
- first_name: E.S.
  full_name: Miles, E.S.
  last_name: Miles
- first_name: S.
  full_name: Jola, S.
  last_name: Jola
- first_name: P.
  full_name: Buri, P.
  last_name: Buri
- first_name: S.
  full_name: Herreid, S.
  last_name: Herreid
- first_name: A.
  full_name: Bhattacharya, A.
  last_name: Bhattacharya
- first_name: C.S.
  full_name: Watson, C.S.
  last_name: Watson
- first_name: T.
  full_name: Bolch, T.
  last_name: Bolch
- first_name: D.
  full_name: Quincey, D.
  last_name: Quincey
- first_name: Francesca
  full_name: Pellicciotti, Francesca
  id: b28f055a-81ea-11ed-b70c-a9fe7f7b0e70
  last_name: Pellicciotti
citation:
  ama: Kneib M, Miles ES, Jola S, et al. Mapping ice cliffs on debris-covered glaciers
    using multispectral satellite images. <i>Remote Sensing of Environment</i>. 2021;253(2).
    doi:<a href="https://doi.org/10.1016/j.rse.2020.112201">10.1016/j.rse.2020.112201</a>
  apa: Kneib, M., Miles, E. S., Jola, S., Buri, P., Herreid, S., Bhattacharya, A.,
    … Pellicciotti, F. (2021). Mapping ice cliffs on debris-covered glaciers using
    multispectral satellite images. <i>Remote Sensing of Environment</i>. Elsevier.
    <a href="https://doi.org/10.1016/j.rse.2020.112201">https://doi.org/10.1016/j.rse.2020.112201</a>
  chicago: Kneib, M., E.S. Miles, S. Jola, P. Buri, S. Herreid, A. Bhattacharya, C.S.
    Watson, T. Bolch, D. Quincey, and Francesca Pellicciotti. “Mapping Ice Cliffs
    on Debris-Covered Glaciers Using Multispectral Satellite Images.” <i>Remote Sensing
    of Environment</i>. Elsevier, 2021. <a href="https://doi.org/10.1016/j.rse.2020.112201">https://doi.org/10.1016/j.rse.2020.112201</a>.
  ieee: M. Kneib <i>et al.</i>, “Mapping ice cliffs on debris-covered glaciers using
    multispectral satellite images,” <i>Remote Sensing of Environment</i>, vol. 253,
    no. 2. Elsevier, 2021.
  ista: Kneib M, Miles ES, Jola S, Buri P, Herreid S, Bhattacharya A, Watson CS, Bolch
    T, Quincey D, Pellicciotti F. 2021. Mapping ice cliffs on debris-covered glaciers
    using multispectral satellite images. Remote Sensing of Environment. 253(2), 112201.
  mla: Kneib, M., et al. “Mapping Ice Cliffs on Debris-Covered Glaciers Using Multispectral
    Satellite Images.” <i>Remote Sensing of Environment</i>, vol. 253, no. 2, 112201,
    Elsevier, 2021, doi:<a href="https://doi.org/10.1016/j.rse.2020.112201">10.1016/j.rse.2020.112201</a>.
  short: M. Kneib, E.S. Miles, S. Jola, P. Buri, S. Herreid, A. Bhattacharya, C.S.
    Watson, T. Bolch, D. Quincey, F. Pellicciotti, Remote Sensing of Environment 253
    (2021).
date_created: 2023-02-20T08:12:00Z
date_published: 2021-02-01T00:00:00Z
date_updated: 2023-02-28T12:53:46Z
day: '01'
doi: 10.1016/j.rse.2020.112201
extern: '1'
intvolume: '       253'
issue: '2'
keyword:
- Computers in Earth Sciences
- Geology
- Soil Science
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.1016/j.rse.2020.112201
month: '02'
oa: 1
oa_version: Published Version
publication: Remote Sensing of Environment
publication_identifier:
  issn:
  - 0034-4257
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Mapping ice cliffs on debris-covered glaciers using multispectral satellite
  images
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 253
year: '2021'
...
---
_id: '12614'
abstract:
- lang: eng
  text: Debris-covered glaciers in the Himalaya may have spatially-averaged rates
    of surface height change that are similar to those observed on bare-ice glaciers,
    despite the insulating effects of thick debris. Spatially heterogeneous melt patterns
    caused by the development and evolution of ice cliffs and supraglacial pond systems
    result in substantial mass losses over time. However, mechanisms controlling the
    formation and survival of cliffs and ponds remain largely unknown. To study the
    distribution and characteristics of these surface features we deploy an unmanned
    aerial vehicle (UAV) over a stretch of the debris-covered Langtang Glacier, Nepal.
    Acquired images are processed into high-resolution orthomosaics and elevation
    models with the Structure from Motion (SfM) photogrammetry algorithm. Ice cliffs
    and ponds are classified using object-based image analysis (OBIA) and their morphology
    and spatial distribution are analysed and evaluated using object, pixel and point
    cloud approaches. Results show that ice cliffs are predominantly north-facing,
    and larger ice cliffs are generally coupled with supraglacial ponds, which may
    affect their evolution considerably. The spatial distribution of ice cliffs indicates
    that they are more likely to form in areas where high strain rates are expected.
    The spatial configuration of ponds over the entire tongue reveals high pond density
    near confluences, possibly due to closure of conduits via transverse compression.
    We conclude that the combination of OBIA and UAV imagery is a valuable tool in
    the semi-automatic and objective analysis of surface features on debris-covered
    glaciers. The technique may also have potential for upscaling to the use of spaceborne
    imagery, and the use of UAV-derived point clouds to analyse ice cliff undercuts
    is promising.
article_processing_charge: No
article_type: original
author:
- first_name: P.D.A.
  full_name: Kraaijenbrink, P.D.A.
  last_name: Kraaijenbrink
- first_name: J.M.
  full_name: Shea, J.M.
  last_name: Shea
- first_name: Francesca
  full_name: Pellicciotti, Francesca
  id: b28f055a-81ea-11ed-b70c-a9fe7f7b0e70
  last_name: Pellicciotti
- first_name: S.M. de
  full_name: Jong, S.M. de
  last_name: Jong
- first_name: W.W.
  full_name: Immerzeel, W.W.
  last_name: Immerzeel
citation:
  ama: Kraaijenbrink PDA, Shea JM, Pellicciotti F, Jong SM de, Immerzeel WW. Object-based
    analysis of unmanned aerial vehicle imagery to map and characterise surface features
    on a debris-covered glacier. <i>Remote Sensing of Environment</i>. 2016;186:581-595.
    doi:<a href="https://doi.org/10.1016/j.rse.2016.09.013">10.1016/j.rse.2016.09.013</a>
  apa: Kraaijenbrink, P. D. A., Shea, J. M., Pellicciotti, F., Jong, S. M. de, &#38;
    Immerzeel, W. W. (2016). Object-based analysis of unmanned aerial vehicle imagery
    to map and characterise surface features on a debris-covered glacier. <i>Remote
    Sensing of Environment</i>. Elsevier. <a href="https://doi.org/10.1016/j.rse.2016.09.013">https://doi.org/10.1016/j.rse.2016.09.013</a>
  chicago: Kraaijenbrink, P.D.A., J.M. Shea, Francesca Pellicciotti, S.M. de Jong,
    and W.W. Immerzeel. “Object-Based Analysis of Unmanned Aerial Vehicle Imagery
    to Map and Characterise Surface Features on a Debris-Covered Glacier.” <i>Remote
    Sensing of Environment</i>. Elsevier, 2016. <a href="https://doi.org/10.1016/j.rse.2016.09.013">https://doi.org/10.1016/j.rse.2016.09.013</a>.
  ieee: P. D. A. Kraaijenbrink, J. M. Shea, F. Pellicciotti, S. M. de Jong, and W.
    W. Immerzeel, “Object-based analysis of unmanned aerial vehicle imagery to map
    and characterise surface features on a debris-covered glacier,” <i>Remote Sensing
    of Environment</i>, vol. 186. Elsevier, pp. 581–595, 2016.
  ista: Kraaijenbrink PDA, Shea JM, Pellicciotti F, Jong SM de, Immerzeel WW. 2016.
    Object-based analysis of unmanned aerial vehicle imagery to map and characterise
    surface features on a debris-covered glacier. Remote Sensing of Environment. 186,
    581–595.
  mla: Kraaijenbrink, P. D. A., et al. “Object-Based Analysis of Unmanned Aerial Vehicle
    Imagery to Map and Characterise Surface Features on a Debris-Covered Glacier.”
    <i>Remote Sensing of Environment</i>, vol. 186, Elsevier, 2016, pp. 581–95, doi:<a
    href="https://doi.org/10.1016/j.rse.2016.09.013">10.1016/j.rse.2016.09.013</a>.
  short: P.D.A. Kraaijenbrink, J.M. Shea, F. Pellicciotti, S.M. de Jong, W.W. Immerzeel,
    Remote Sensing of Environment 186 (2016) 581–595.
date_created: 2023-02-20T08:14:35Z
date_published: 2016-12-01T00:00:00Z
date_updated: 2023-02-24T11:31:58Z
day: '01'
doi: 10.1016/j.rse.2016.09.013
extern: '1'
intvolume: '       186'
keyword:
- Computers in Earth Sciences
- Geology
- Soil Science
language:
- iso: eng
month: '12'
oa_version: None
page: 581-595
publication: Remote Sensing of Environment
publication_identifier:
  issn:
  - 0034-4257
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Object-based analysis of unmanned aerial vehicle imagery to map and characterise
  surface features on a debris-covered glacier
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 186
year: '2016'
...
---
_id: '12636'
abstract:
- lang: eng
  text: Himalayan glacier tongues are commonly debris covered and they are an important
    source of melt water. However, they remain relatively unstudied because of the
    inaccessibility of the terrain and the difficulties in field work caused by the
    thick debris mantles. Observations of debris-covered glaciers are therefore scarce
    and airborne remote sensing may bridge the gap between scarce field observations
    and coarse resolution space-borne remote sensing. In this study we deploy an Unmanned
    Aerial Vehicle (UAV) before and after the melt and monsoon season (May and October
    2013) over the debris-covered tongue of the Lirung Glacier in Nepal. Based on
    stereo-imaging and the structure for motion algorithm we derive highly detailed
    ortho-mosaics and digital elevation models (DEMs), which we geometrically correct
    using differential GPS observations collected in the field. Based on DEM differencing
    and manual feature tracking we derive the mass loss and the surface velocity of
    the glacier at a high spatial accuracy. On average, mass loss is limited and the
    surface velocity is very small. However, the spatial variability of melt rates
    is very high, and ice cliffs and supra-glacial ponds show mass losses that can
    be an order of magnitude higher than the average. We suggest that future research
    should focus on the interaction between supra-glacial ponds, ice cliffs and englacial
    hydrology to further understand the dynamics of debris-covered glaciers. Finally,
    we conclude that UAV deployment has large potential in glaciology and it may revolutionize
    methods currently applied in studying glacier surface features.
article_processing_charge: No
article_type: original
author:
- first_name: W.W.
  full_name: Immerzeel, W.W.
  last_name: Immerzeel
- first_name: P.D.A.
  full_name: Kraaijenbrink, P.D.A.
  last_name: Kraaijenbrink
- first_name: J.M.
  full_name: Shea, J.M.
  last_name: Shea
- first_name: A.B.
  full_name: Shrestha, A.B.
  last_name: Shrestha
- first_name: Francesca
  full_name: Pellicciotti, Francesca
  id: b28f055a-81ea-11ed-b70c-a9fe7f7b0e70
  last_name: Pellicciotti
- first_name: M.F.P.
  full_name: Bierkens, M.F.P.
  last_name: Bierkens
- first_name: S.M.
  full_name: de Jong, S.M.
  last_name: de Jong
citation:
  ama: Immerzeel WW, Kraaijenbrink PDA, Shea JM, et al. High-resolution monitoring
    of Himalayan glacier dynamics using unmanned aerial vehicles. <i>Remote Sensing
    of Environment</i>. 2014;150(7):93-103. doi:<a href="https://doi.org/10.1016/j.rse.2014.04.025">10.1016/j.rse.2014.04.025</a>
  apa: Immerzeel, W. W., Kraaijenbrink, P. D. A., Shea, J. M., Shrestha, A. B., Pellicciotti,
    F., Bierkens, M. F. P., &#38; de Jong, S. M. (2014). High-resolution monitoring
    of Himalayan glacier dynamics using unmanned aerial vehicles. <i>Remote Sensing
    of Environment</i>. Elsevier. <a href="https://doi.org/10.1016/j.rse.2014.04.025">https://doi.org/10.1016/j.rse.2014.04.025</a>
  chicago: Immerzeel, W.W., P.D.A. Kraaijenbrink, J.M. Shea, A.B. Shrestha, Francesca
    Pellicciotti, M.F.P. Bierkens, and S.M. de Jong. “High-Resolution Monitoring of
    Himalayan Glacier Dynamics Using Unmanned Aerial Vehicles.” <i>Remote Sensing
    of Environment</i>. Elsevier, 2014. <a href="https://doi.org/10.1016/j.rse.2014.04.025">https://doi.org/10.1016/j.rse.2014.04.025</a>.
  ieee: W. W. Immerzeel <i>et al.</i>, “High-resolution monitoring of Himalayan glacier
    dynamics using unmanned aerial vehicles,” <i>Remote Sensing of Environment</i>,
    vol. 150, no. 7. Elsevier, pp. 93–103, 2014.
  ista: Immerzeel WW, Kraaijenbrink PDA, Shea JM, Shrestha AB, Pellicciotti F, Bierkens
    MFP, de Jong SM. 2014. High-resolution monitoring of Himalayan glacier dynamics
    using unmanned aerial vehicles. Remote Sensing of Environment. 150(7), 93–103.
  mla: Immerzeel, W. W., et al. “High-Resolution Monitoring of Himalayan Glacier Dynamics
    Using Unmanned Aerial Vehicles.” <i>Remote Sensing of Environment</i>, vol. 150,
    no. 7, Elsevier, 2014, pp. 93–103, doi:<a href="https://doi.org/10.1016/j.rse.2014.04.025">10.1016/j.rse.2014.04.025</a>.
  short: W.W. Immerzeel, P.D.A. Kraaijenbrink, J.M. Shea, A.B. Shrestha, F. Pellicciotti,
    M.F.P. Bierkens, S.M. de Jong, Remote Sensing of Environment 150 (2014) 93–103.
date_created: 2023-02-20T08:16:56Z
date_published: 2014-07-01T00:00:00Z
date_updated: 2023-02-24T08:32:39Z
day: '01'
doi: 10.1016/j.rse.2014.04.025
extern: '1'
intvolume: '       150'
issue: '7'
keyword:
- Computers in Earth Sciences
- Geology
- Soil Science
language:
- iso: eng
month: '07'
oa_version: None
page: 93-103
publication: Remote Sensing of Environment
publication_identifier:
  issn:
  - 0034-4257
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: High-resolution monitoring of Himalayan glacier dynamics using unmanned aerial
  vehicles
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 150
year: '2014'
...