The impact of supraglacial debris on proglacial runoff and water chemistry

C. L. Fyffe (Lead / Corresponding author), B. W. Brock, M. P. Kirkbride, A. R. Black, C. Smiraglia, G. Diolaiuti

Research output: Contribution to journalArticle

14 Downloads (Pure)

Abstract

Debris is known to influence the ablation, topography and hydrological systems of glaciers. This paper determines for the first time how these influences impact on bulk water routing and the proglacial runoff signal, using analyses of supraglacial and proglacial water chemistry and proglacial discharge at Miage Glacier, Italian Alps. Debris does influence the supraglacial water chemistry, but the inefficient subglacial system beneath the debris-covered zone also plays a role in increasing the ion contribution to the proglacial stream. Daily hydrographs had a lower amplitude and later discharge peak compared to clean glaciers and fewer diurnal hydrographs were found compared to similar analysis for Haut Glacier d'Arolla. We attribute these observations to the attenuating effect of the debris on ablation, smaller input streams on the debris-covered area, a less efficient subglacial system, and possible leakage into a raised sediment bed beneath the glacier. Strongly diurnal hydrographs are constrained to periods with warmer than average conditions. ‘Average’ weather conditions result in a hydrograph with reverse asymmetry. Conductivity and discharge commonly show anti-clockwise hysteresis, suggesting the more dilute, rapidly-routed melt component from the mid-glacier peaks before the discharge peak, with components from higher up-glacier and the debris-covered areas arriving later at the proglacial stream. The results of this study could lead to a greater understanding of the hydrological structure of other debris-covered glaciers, with findings highlighting the need to include the influence of the debris cover within future models of debris-covered glacier runoff.

Original languageEnglish
Pages (from-to)41-57
Number of pages17
JournalJournal of Hydrology
Volume576
Early online date10 Jun 2019
DOIs
Publication statusPublished - Sep 2019

Fingerprint

water chemistry
glacier
runoff
hydrograph
peak discharge
ablation
routing
hysteresis
leakage
asymmetry
conductivity
melt
topography
ion
sediment

Keywords

  • Debris-covered glaciers
  • Glacier hydrochemistry
  • Glacier hydrology
  • Proglacial discharge
  • Suspended sediment concentration

Cite this

Fyffe, C. L. ; Brock, B. W. ; Kirkbride, M. P. ; Black, A. R. ; Smiraglia, C. ; Diolaiuti, G. / The impact of supraglacial debris on proglacial runoff and water chemistry. In: Journal of Hydrology. 2019 ; Vol. 576. pp. 41-57.
@article{a2738dd444e84b919078dca1fee1805d,
title = "The impact of supraglacial debris on proglacial runoff and water chemistry",
abstract = "Debris is known to influence the ablation, topography and hydrological systems of glaciers. This paper determines for the first time how these influences impact on bulk water routing and the proglacial runoff signal, using analyses of supraglacial and proglacial water chemistry and proglacial discharge at Miage Glacier, Italian Alps. Debris does influence the supraglacial water chemistry, but the inefficient subglacial system beneath the debris-covered zone also plays a role in increasing the ion contribution to the proglacial stream. Daily hydrographs had a lower amplitude and later discharge peak compared to clean glaciers and fewer diurnal hydrographs were found compared to similar analysis for Haut Glacier d'Arolla. We attribute these observations to the attenuating effect of the debris on ablation, smaller input streams on the debris-covered area, a less efficient subglacial system, and possible leakage into a raised sediment bed beneath the glacier. Strongly diurnal hydrographs are constrained to periods with warmer than average conditions. ‘Average’ weather conditions result in a hydrograph with reverse asymmetry. Conductivity and discharge commonly show anti-clockwise hysteresis, suggesting the more dilute, rapidly-routed melt component from the mid-glacier peaks before the discharge peak, with components from higher up-glacier and the debris-covered areas arriving later at the proglacial stream. The results of this study could lead to a greater understanding of the hydrological structure of other debris-covered glaciers, with findings highlighting the need to include the influence of the debris cover within future models of debris-covered glacier runoff.",
keywords = "Debris-covered glaciers, Glacier hydrochemistry, Glacier hydrology, Proglacial discharge, Suspended sediment concentration",
author = "Fyffe, {C. L.} and Brock, {B. W.} and Kirkbride, {M. P.} and Black, {A. R.} and C. Smiraglia and G. Diolaiuti",
year = "2019",
month = "9",
doi = "10.1016/j.jhydrol.2019.06.023",
language = "English",
volume = "576",
pages = "41--57",
journal = "Journal of Hydrology",
issn = "0022-1694",
publisher = "Elsevier",

}

The impact of supraglacial debris on proglacial runoff and water chemistry. / Fyffe, C. L. (Lead / Corresponding author); Brock, B. W.; Kirkbride, M. P.; Black, A. R.; Smiraglia, C.; Diolaiuti, G.

In: Journal of Hydrology, Vol. 576, 09.2019, p. 41-57.

Research output: Contribution to journalArticle

TY - JOUR

T1 - The impact of supraglacial debris on proglacial runoff and water chemistry

AU - Fyffe, C. L.

AU - Brock, B. W.

AU - Kirkbride, M. P.

AU - Black, A. R.

AU - Smiraglia, C.

AU - Diolaiuti, G.

PY - 2019/9

Y1 - 2019/9

N2 - Debris is known to influence the ablation, topography and hydrological systems of glaciers. This paper determines for the first time how these influences impact on bulk water routing and the proglacial runoff signal, using analyses of supraglacial and proglacial water chemistry and proglacial discharge at Miage Glacier, Italian Alps. Debris does influence the supraglacial water chemistry, but the inefficient subglacial system beneath the debris-covered zone also plays a role in increasing the ion contribution to the proglacial stream. Daily hydrographs had a lower amplitude and later discharge peak compared to clean glaciers and fewer diurnal hydrographs were found compared to similar analysis for Haut Glacier d'Arolla. We attribute these observations to the attenuating effect of the debris on ablation, smaller input streams on the debris-covered area, a less efficient subglacial system, and possible leakage into a raised sediment bed beneath the glacier. Strongly diurnal hydrographs are constrained to periods with warmer than average conditions. ‘Average’ weather conditions result in a hydrograph with reverse asymmetry. Conductivity and discharge commonly show anti-clockwise hysteresis, suggesting the more dilute, rapidly-routed melt component from the mid-glacier peaks before the discharge peak, with components from higher up-glacier and the debris-covered areas arriving later at the proglacial stream. The results of this study could lead to a greater understanding of the hydrological structure of other debris-covered glaciers, with findings highlighting the need to include the influence of the debris cover within future models of debris-covered glacier runoff.

AB - Debris is known to influence the ablation, topography and hydrological systems of glaciers. This paper determines for the first time how these influences impact on bulk water routing and the proglacial runoff signal, using analyses of supraglacial and proglacial water chemistry and proglacial discharge at Miage Glacier, Italian Alps. Debris does influence the supraglacial water chemistry, but the inefficient subglacial system beneath the debris-covered zone also plays a role in increasing the ion contribution to the proglacial stream. Daily hydrographs had a lower amplitude and later discharge peak compared to clean glaciers and fewer diurnal hydrographs were found compared to similar analysis for Haut Glacier d'Arolla. We attribute these observations to the attenuating effect of the debris on ablation, smaller input streams on the debris-covered area, a less efficient subglacial system, and possible leakage into a raised sediment bed beneath the glacier. Strongly diurnal hydrographs are constrained to periods with warmer than average conditions. ‘Average’ weather conditions result in a hydrograph with reverse asymmetry. Conductivity and discharge commonly show anti-clockwise hysteresis, suggesting the more dilute, rapidly-routed melt component from the mid-glacier peaks before the discharge peak, with components from higher up-glacier and the debris-covered areas arriving later at the proglacial stream. The results of this study could lead to a greater understanding of the hydrological structure of other debris-covered glaciers, with findings highlighting the need to include the influence of the debris cover within future models of debris-covered glacier runoff.

KW - Debris-covered glaciers

KW - Glacier hydrochemistry

KW - Glacier hydrology

KW - Proglacial discharge

KW - Suspended sediment concentration

UR - http://www.scopus.com/inward/record.url?scp=85067690876&partnerID=8YFLogxK

U2 - 10.1016/j.jhydrol.2019.06.023

DO - 10.1016/j.jhydrol.2019.06.023

M3 - Article

AN - SCOPUS:85067690876

VL - 576

SP - 41

EP - 57

JO - Journal of Hydrology

JF - Journal of Hydrology

SN - 0022-1694

ER -