[{"author":[{"full_name":"Melo Velasco, Juan Vicente","last_name":"Melo Velasco","first_name":"Juan Vicente","id":"2611dec0-b9c6-11ed-9bea-a81c2b17a549"},{"full_name":"Miles, Evan","last_name":"Miles","first_name":"Evan"},{"first_name":"Michael","id":"22a2674a-61ce-11ee-94b5-d18813baf16f","last_name":"McCarthy","full_name":"McCarthy, Michael"},{"id":"3caa3f91-1f03-11ee-96ce-e0e553054d6e","first_name":"Thomas","last_name":"Shaw","orcid":"0000-0001-7640-6152","full_name":"Shaw, Thomas"},{"full_name":"Fyffe, Catriona Louise","last_name":"Fyffe","id":"001b0422-8d15-11ed-bc51-cab6c037a228","first_name":"Catriona Louise"},{"first_name":"Adrià","id":"f06891fd-9f42-11ee-8632-a20971c43046","last_name":"Fontrodona-Bach","full_name":"Fontrodona-Bach, Adrià"},{"first_name":"Francesca","id":"b28f055a-81ea-11ed-b70c-a9fe7f7b0e70","last_name":"Pellicciotti","full_name":"Pellicciotti, Francesca","orcid":"0000-0002-5554-8087"}],"doi":"10.1029/2025jf008360","month":"06","scopus_import":"1","volume":130,"article_type":"original","oa_version":"Published Version","corr_author":"1","publisher":"Wiley","day":"15","oa":1,"publication":"Journal of Geophysical Research: Earth Surface","article_number":"e2025JF008360","abstract":[{"lang":"eng","text":"Rock debris partially covers glaciers worldwide, with varying extents and distributions, and controls sub‐debris melt rates by modifying energy transfer from the atmosphere to the ice. Two key physical properties controlling this energy exchange are thermal conductivity (k) and aerodynamic roughness length (z0). Accurate representation of these properties in energy‐balance models is critical for understanding climate‐glacier interactions and predicting the behavior of debris‐covered glaciers. However, k and z0 have been derived at very few sites from limited local measurements, using different approaches, and most model applications rely on values reported from these few sites and studies. We derive k and z0 using established and modified approaches from data at three locations on Pirámide Glacier in the central Chilean Andes. By comparing methods and evaluating melt simulated with an energy‐balance model, we reveal substantial differences between approaches. These lead to discrepancies between ice melt from energy‐balance simulations and observed data, and highlight the impact of method choice on calculated ice melt. Optimizing k against measured melt appears a viable approach to constrain melt simulations. Determining z0 seems less critical, as it has a smaller impact on total melt. Profile aerodynamic method measurements for estimating z0, despite higher costs, are independent of ice melt calculations. The large, unexpected differences between methods indicate a substantial knowledge gap. The fact that field‐derived k and z0 fail to work well in energy‐balance models, suggests that model values represent bulk properties distinct from theoretical field measurements. Addressing this gap is essential for improving glacier melt predictions."}],"status":"public","ddc":["550"],"quality_controlled":"1","OA_place":"publisher","publication_identifier":{"eissn":["2169-9011"],"issn":["2169-9003"]},"tmp":{"short":"CC BY (4.0)","image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"has_accepted_license":"1","title":"Method dependence in thermal conductivity and aerodynamic roughness length estimates on a debris‐covered glacier","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","external_id":{"isi":["001508794200001"]},"department":[{"_id":"FrPe"}],"file_date_updated":"2025-06-24T06:27:34Z","file":[{"date_created":"2025-06-24T06:27:34Z","checksum":"ca91541516c71d240321630ca42b4dc4","file_id":"19886","success":1,"date_updated":"2025-06-24T06:27:34Z","file_size":3949928,"relation":"main_file","file_name":"2025_JGREarthSurface_MeloVelasco.pdf","access_level":"open_access","creator":"dernst","content_type":"application/pdf"}],"issue":"6","license":"https://creativecommons.org/licenses/by/4.0/","_id":"19878","acknowledgement":"This project received funding from the Swiss National Science Foundation (Grant 204322, project “REsolving the thickNess Of debris on Earth's glacIers and its Rate of change,” RENOIR). We thank Lars Groeneveld, Diego Hernández, Alonso Mejías, Gabriela Reyes and Gabriela Tala for their support during fieldwork. Open access funding provided by Institute of Science and Technology Austria/KEMÖ.","isi":1,"type":"journal_article","intvolume":"       130","date_updated":"2025-09-30T13:42:28Z","year":"2025","date_created":"2025-06-23T13:54:01Z","date_published":"2025-06-15T00:00:00Z","publication_status":"published","citation":{"ieee":"J. V. Melo Velasco <i>et al.</i>, “Method dependence in thermal conductivity and aerodynamic roughness length estimates on a debris‐covered glacier,” <i>Journal of Geophysical Research: Earth Surface</i>, vol. 130, no. 6. Wiley, 2025.","short":"J.V. Melo Velasco, E. Miles, M. McCarthy, T. Shaw, C.L. Fyffe, A. Fontrodona-Bach, F. Pellicciotti, Journal of Geophysical Research: Earth Surface 130 (2025).","mla":"Melo Velasco, Juan Vicente, et al. “Method Dependence in Thermal Conductivity and Aerodynamic Roughness Length Estimates on a Debris‐covered Glacier.” <i>Journal of Geophysical Research: Earth Surface</i>, vol. 130, no. 6, e2025JF008360, Wiley, 2025, doi:<a href=\"https://doi.org/10.1029/2025jf008360\">10.1029/2025jf008360</a>.","ista":"Melo Velasco JV, Miles E, McCarthy M, Shaw T, Fyffe CL, Fontrodona-Bach A, Pellicciotti F. 2025. Method dependence in thermal conductivity and aerodynamic roughness length estimates on a debris‐covered glacier. Journal of Geophysical Research: Earth Surface. 130(6), e2025JF008360.","apa":"Melo Velasco, J. V., Miles, E., McCarthy, M., Shaw, T., Fyffe, C. L., Fontrodona-Bach, A., &#38; Pellicciotti, F. (2025). Method dependence in thermal conductivity and aerodynamic roughness length estimates on a debris‐covered glacier. <i>Journal of Geophysical Research: Earth Surface</i>. Wiley. <a href=\"https://doi.org/10.1029/2025jf008360\">https://doi.org/10.1029/2025jf008360</a>","chicago":"Melo Velasco, Juan Vicente, Evan Miles, Michael McCarthy, Thomas Shaw, Catriona Louise Fyffe, Adrià Fontrodona-Bach, and Francesca Pellicciotti. “Method Dependence in Thermal Conductivity and Aerodynamic Roughness Length Estimates on a Debris‐covered Glacier.” <i>Journal of Geophysical Research: Earth Surface</i>. Wiley, 2025. <a href=\"https://doi.org/10.1029/2025jf008360\">https://doi.org/10.1029/2025jf008360</a>.","ama":"Melo Velasco JV, Miles E, McCarthy M, et al. Method dependence in thermal conductivity and aerodynamic roughness length estimates on a debris‐covered glacier. <i>Journal of Geophysical Research: Earth Surface</i>. 2025;130(6). doi:<a href=\"https://doi.org/10.1029/2025jf008360\">10.1029/2025jf008360</a>"},"language":[{"iso":"eng"}],"OA_type":"hybrid","article_processing_charge":"Yes (via OA deal)"},{"author":[{"full_name":"Kneib, M.","last_name":"Kneib","first_name":"M."},{"first_name":"E. S.","last_name":"Miles","full_name":"Miles, E. S."},{"first_name":"P.","last_name":"Buri","full_name":"Buri, P."},{"last_name":"Molnar","first_name":"P.","full_name":"Molnar, P."},{"last_name":"McCarthy","first_name":"M.","full_name":"McCarthy, M."},{"first_name":"S.","last_name":"Fugger","full_name":"Fugger, S."},{"first_name":"Francesca","id":"b28f055a-81ea-11ed-b70c-a9fe7f7b0e70","last_name":"Pellicciotti","full_name":"Pellicciotti, Francesca"}],"doi":"10.1029/2021jf006179","month":"10","article_type":"original","scopus_import":"1","volume":126,"oa_version":"Published Version","publisher":"American Geophysical Union","oa":1,"day":"01","publication":"Journal of Geophysical Research: Earth Surface","extern":"1","main_file_link":[{"url":"https://doi.org/10.1029/2021JF006179","open_access":"1"}],"article_number":"e2021JF006179","abstract":[{"lang":"eng","text":"Ice cliffs are common on debris-covered glaciers and have relatively high melt rates due to their direct exposure to incoming radiation. Previous studies have shown that their number and relative area can change considerably from year to year, but this variability has not been explored, in part because available cliff observations are irregular. Here, we systematically mapped and tracked ice cliffs across four debris-covered glaciers in High Mountain Asia for every late ablation season from 2009 to 2019 using high-resolution multi-spectral satellite imagery. We then quantified the processes occurring at the feature scale to train a stochastic birth-death model to represent the cliff population dynamics. Our results show that while the cliff relative area can change by up to 20% from year to year, the natural long-term variability is constrained, thus defining a glacier-specific cliff carrying capacity. In a subsequent step, the inclusion of external drivers related to climate, glacier dynamics, and hydrology highlights the influence of these variables on the cliff population dynamics, which is usually not a direct one due to the complexity and interdependence of the processes taking place at the glacier surface. In some extreme cases (here, a glacier surge), these external drivers may lead to a reorganization of the cliffs at the glacier surface and a change in the natural variability. These results have implications for the melt of debris-covered glaciers, in addition to showing the high rate of changes at their surface and highlighting some of the links between cliff population and glacier state."}],"status":"public","keyword":["Earth-Surface Processes","Geophysics"],"quality_controlled":"1","publication_identifier":{"issn":["2169-9003","2169-9011"]},"title":"Interannual dynamics of ice cliff populations on debris‐covered glaciers from remote sensing observations and stochastic modeling","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","issue":"10","_id":"12586","type":"journal_article","date_updated":"2023-02-28T13:18:26Z","intvolume":"       126","year":"2021","date_created":"2023-02-20T08:11:36Z","date_published":"2021-10-01T00:00:00Z","publication_status":"published","language":[{"iso":"eng"}],"article_processing_charge":"No","citation":{"ieee":"M. Kneib <i>et al.</i>, “Interannual dynamics of ice cliff populations on debris‐covered glaciers from remote sensing observations and stochastic modeling,” <i>Journal of Geophysical Research: Earth Surface</i>, vol. 126, no. 10. American Geophysical Union, 2021.","short":"M. Kneib, E.S. Miles, P. Buri, P. Molnar, M. McCarthy, S. Fugger, F. Pellicciotti, Journal of Geophysical Research: Earth Surface 126 (2021).","apa":"Kneib, M., Miles, E. S., Buri, P., Molnar, P., McCarthy, M., Fugger, S., &#38; Pellicciotti, F. (2021). Interannual dynamics of ice cliff populations on debris‐covered glaciers from remote sensing observations and stochastic modeling. <i>Journal of Geophysical Research: Earth Surface</i>. American Geophysical Union. <a href=\"https://doi.org/10.1029/2021jf006179\">https://doi.org/10.1029/2021jf006179</a>","chicago":"Kneib, M., E. S. Miles, P. Buri, P. Molnar, M. McCarthy, S. Fugger, and Francesca Pellicciotti. “Interannual Dynamics of Ice Cliff Populations on Debris‐covered Glaciers from Remote Sensing Observations and Stochastic Modeling.” <i>Journal of Geophysical Research: Earth Surface</i>. American Geophysical Union, 2021. <a href=\"https://doi.org/10.1029/2021jf006179\">https://doi.org/10.1029/2021jf006179</a>.","ama":"Kneib M, Miles ES, Buri P, et al. Interannual dynamics of ice cliff populations on debris‐covered glaciers from remote sensing observations and stochastic modeling. <i>Journal of Geophysical Research: Earth Surface</i>. 2021;126(10). doi:<a href=\"https://doi.org/10.1029/2021jf006179\">10.1029/2021jf006179</a>","mla":"Kneib, M., et al. “Interannual Dynamics of Ice Cliff Populations on Debris‐covered Glaciers from Remote Sensing Observations and Stochastic Modeling.” <i>Journal of Geophysical Research: Earth Surface</i>, vol. 126, no. 10, e2021JF006179, American Geophysical Union, 2021, doi:<a href=\"https://doi.org/10.1029/2021jf006179\">10.1029/2021jf006179</a>.","ista":"Kneib M, Miles ES, Buri P, Molnar P, McCarthy M, Fugger S, Pellicciotti F. 2021. Interannual dynamics of ice cliff populations on debris‐covered glaciers from remote sensing observations and stochastic modeling. Journal of Geophysical Research: Earth Surface. 126(10), e2021JF006179."}},{"_id":"12613","page":"2471-2493","publication_status":"published","article_processing_charge":"No","citation":{"chicago":"Buri, Pascal, Evan S. Miles, Jakob F. Steiner, Walter W. Immerzeel, Patrick Wagnon, and Francesca Pellicciotti. “A Physically Based 3‐D Model of Ice Cliff Evolution over Debris‐covered Glaciers.” <i>Journal of Geophysical Research: Earth Surface</i>. American Geophysical Union, 2016. <a href=\"https://doi.org/10.1002/2016jf004039\">https://doi.org/10.1002/2016jf004039</a>.","ama":"Buri P, Miles ES, Steiner JF, Immerzeel WW, Wagnon P, Pellicciotti F. A physically based 3‐D model of ice cliff evolution over debris‐covered glaciers. <i>Journal of Geophysical Research: Earth Surface</i>. 2016;121(12):2471-2493. doi:<a href=\"https://doi.org/10.1002/2016jf004039\">10.1002/2016jf004039</a>","apa":"Buri, P., Miles, E. S., Steiner, J. F., Immerzeel, W. W., Wagnon, P., &#38; Pellicciotti, F. (2016). A physically based 3‐D model of ice cliff evolution over debris‐covered glaciers. <i>Journal of Geophysical Research: Earth Surface</i>. American Geophysical Union. <a href=\"https://doi.org/10.1002/2016jf004039\">https://doi.org/10.1002/2016jf004039</a>","ista":"Buri P, Miles ES, Steiner JF, Immerzeel WW, Wagnon P, Pellicciotti F. 2016. A physically based 3‐D model of ice cliff evolution over debris‐covered glaciers. Journal of Geophysical Research: Earth Surface. 121(12), 2471–2493.","mla":"Buri, Pascal, et al. “A Physically Based 3‐D Model of Ice Cliff Evolution over Debris‐covered Glaciers.” <i>Journal of Geophysical Research: Earth Surface</i>, vol. 121, no. 12, American Geophysical Union, 2016, pp. 2471–93, doi:<a href=\"https://doi.org/10.1002/2016jf004039\">10.1002/2016jf004039</a>.","ieee":"P. Buri, E. S. Miles, J. F. Steiner, W. W. Immerzeel, P. Wagnon, and F. Pellicciotti, “A physically based 3‐D model of ice cliff evolution over debris‐covered glaciers,” <i>Journal of Geophysical Research: Earth Surface</i>, vol. 121, no. 12. American Geophysical Union, pp. 2471–2493, 2016.","short":"P. Buri, E.S. Miles, J.F. Steiner, W.W. Immerzeel, P. Wagnon, F. Pellicciotti, Journal of Geophysical Research: Earth Surface 121 (2016) 2471–2493."},"language":[{"iso":"eng"}],"date_created":"2023-02-20T08:14:28Z","year":"2016","date_published":"2016-11-22T00:00:00Z","type":"journal_article","intvolume":"       121","date_updated":"2023-02-24T11:34:54Z","title":"A physically based 3‐D model of ice cliff evolution over debris‐covered glaciers","publication_identifier":{"issn":["2169-9003"],"eissn":["2169-9011"]},"issue":"12","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","keyword":["Earth-Surface Processes","Geophysics"],"status":"public","main_file_link":[{"url":"https://doi.org/10.1002/2016JF004039","open_access":"1"}],"abstract":[{"lang":"eng","text":"We use high-resolution digital elevation models (DEMs) from unmanned aerial vehicle (UAV) surveys to document the evolution of four ice cliffs on the debris-covered tongue of Lirung Glacier, Nepal, over one ablation season. Observations show that out of four cliffs, three different patterns of evolution emerge: (i) reclining cliffs that flatten during the ablation season; (ii) stable cliffs that maintain a self-similar geometry; and (iii) growing cliffs, expanding laterally. We use the insights from this unique data set to develop a 3-D model of cliff backwasting and evolution that is validated against observations and an independent data set of volume losses. The model includes ablation at the cliff surface driven by energy exchange with the atmosphere, reburial of cliff cells by surrounding debris, and the effect of adjacent ponds. The cliff geometry is updated monthly to account for the modifications induced by each of those processes. Model results indicate that a major factor affecting the survival of steep cliffs is the coupling with ponded water at its base, which prevents progressive flattening and possible disappearance of a cliff. The radial growth observed at one cliff is explained by higher receipts of longwave and shortwave radiation, calculated taking into account atmospheric fluxes, shading, and the emission of longwave radiation from debris surfaces. The model is a clear step forward compared to existing static approaches that calculate atmospheric melt over an invariant cliff geometry and can be used for long-term simulations of cliff evolution and to test existing hypotheses about cliffs' survival."}],"extern":"1","quality_controlled":"1","oa_version":"Published Version","article_type":"original","scopus_import":"1","volume":121,"month":"11","doi":"10.1002/2016jf004039","author":[{"first_name":"Pascal","last_name":"Buri","full_name":"Buri, Pascal"},{"full_name":"Miles, Evan S.","last_name":"Miles","first_name":"Evan S."},{"last_name":"Steiner","first_name":"Jakob F.","full_name":"Steiner, Jakob F."},{"full_name":"Immerzeel, Walter W.","last_name":"Immerzeel","first_name":"Walter W."},{"first_name":"Patrick","last_name":"Wagnon","full_name":"Wagnon, Patrick"},{"full_name":"Pellicciotti, Francesca","last_name":"Pellicciotti","first_name":"Francesca","id":"b28f055a-81ea-11ed-b70c-a9fe7f7b0e70"}],"day":"22","oa":1,"publication":"Journal of Geophysical Research: Earth Surface","publisher":"American Geophysical Union"}]