We developed a simple model to estimate ice ablation under a debris cover. The ablation process is modelled using energy and mass conservation equations for debris and ice and heat conduction, driven by input of either i) debris surface temperature or ii) radiation fluxes, and solved through a finite difference scheme computing the conductive heat flux within the supra-glacial debris layer. For model calibration, input and validation, we used approximately bi-weekly surveys of ice ablation rate, debris cover temperature, air temperature and solar incoming and upwelling radiation during for Summer 2007. We calibrated the model for debris thermal conductivity using a subset of ablation data and then we validated it using another subset. Comparisons between calculated and measured values showed a good agreement (RMSE = 0.04 m w.e., r = 0.79), thus suggesting a good performance of the model in predicting ice ablation. Thermal conductivity was found to be the most critical parameter in the proposed model, and it was estimated by debris temperature and thickness, with value changing along the investigated ablation season. The proposed model may be used to quantify buried ice ablation given a reasonable assessment of thermal conductivity.

An ablation model for debris-covered ice: The case study of venerocolo glacier (Italian Alps) / D. Bocchiola, A. Senese, C. Mihalcea, B. Mosconi, C. D’Agata, C. Smiraglia, G.A. Diolaiuti. - In: GEOGRAFIA FISICA E DINAMICA QUATERNARIA. - ISSN 0391-9838. - 38:2(2015), pp. 113-128. [10.4461/GFDQ.2015.38.11]

An ablation model for debris-covered ice: The case study of venerocolo glacier (Italian Alps)

A. Senese;C. Mihalcea;B. Mosconi;C. D’Agata
Secondo
;
C. Smiraglia
Penultimo
;
G.A. Diolaiuti
2015

Abstract

We developed a simple model to estimate ice ablation under a debris cover. The ablation process is modelled using energy and mass conservation equations for debris and ice and heat conduction, driven by input of either i) debris surface temperature or ii) radiation fluxes, and solved through a finite difference scheme computing the conductive heat flux within the supra-glacial debris layer. For model calibration, input and validation, we used approximately bi-weekly surveys of ice ablation rate, debris cover temperature, air temperature and solar incoming and upwelling radiation during for Summer 2007. We calibrated the model for debris thermal conductivity using a subset of ablation data and then we validated it using another subset. Comparisons between calculated and measured values showed a good agreement (RMSE = 0.04 m w.e., r = 0.79), thus suggesting a good performance of the model in predicting ice ablation. Thermal conductivity was found to be the most critical parameter in the proposed model, and it was estimated by debris temperature and thickness, with value changing along the investigated ablation season. The proposed model may be used to quantify buried ice ablation given a reasonable assessment of thermal conductivity.
Debris-covered glaciers; Heat conduction; Ice ablation; Italian Alps; Venerocolo Glacier
Settore GEO/04 - Geografia Fisica e Geomorfologia
Settore ICAR/02 - Costruzioni Idrauliche e Marittime e Idrologia
Article (author)
File in questo prodotto:
File Dimensione Formato  
02_GFDQ_38_2_Bocchiola_113_128.pdf

accesso aperto

Descrizione: articolo pubblicato
Tipologia: Publisher's version/PDF
Dimensione 2.14 MB
Formato Adobe PDF
2.14 MB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/2434/360855
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 16
  • ???jsp.display-item.citation.isi??? 16
social impact