Weathering crust processes on melting glacier ice (Alberta, Canada)
Notice bibliographique
Résumé
This thesis examines the relationship between the energy balance and hydrology of a glacier at the ice surface interface during the melt season. Experimental sub-catchments were established on the ablation area of the Peyto Glacier, Alberta, Canada, during the summers of 1994, 1995 and 1997. These sub-catchments were equipped with meteorological and hydrological instrumentation to examine relationships in the surface layer. Specifically, the development of a phenomenon known as the weathering crust is followed by examining the ratio between potential surface lowering (calculated from energy available for melt) and actual surface lowering (as measured in the field). This enables an indirect division of weathering crust development into growth and decay stages. Weathering crust growth is driven by K* while decay is driven by positive inputs of QH + QE + L*. Analysis was undertaken within periods of weathering crust growth, crustal decay and when little or no apparent melt was occurring. Actual differences between measured and potential surface lowering were also calculated. Further, associated stage records for the 1997 field season were examined for periods of weathering crust growth and decay in order to examine lags within the system. This analysis led to the simulation of ice densities at increasing depths within an ice column, based on weathering crust processes. The simulation was driven by data collected in the field. An addition to the simulation which allows for re-freezing of water within the crust indicates that the effect of re-freezing of ice during the melt season is virtually negligible. Further, subsurface priming is indicated under daytime conditions when there is a net energy loss at the surface. It is proposed that the results from the simulations produce a suitable surrogate for indicating the resultant changes in ice density given weathering crust development, thus providing an insight into events in the field. It is concluded that the weathering crust phenomenon is a complex relationship between energy inputs, initial crustal conditions and mechanical thresholds. Daytime weathering crust decay is the most complicated to analyse, as growth and decay are occurring simultaneously, even though decay is the dominant process. Daytime growth and nocturnal decay are the most straightforward cases. Weathering crust development appears to dampen catchment response by increasing storage in the lower density ice in the late morning. Further, the storage capacity of a highly developed weathering crust can result in drainage from the system overnight. This overnight drainage can be compounded by nocturnal crustal decay.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,001 |
| Études des sciences et des technologies | 0,001 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,001 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».