| Morainal bank sediment dynamics affect tidewater terminus stability by controlling grounding-line water depth and calving speed termini dynamics to decouple from climatic forcing. Data presented in this study document regional climatic forcing, termini, and ice-proximal sediment dynamics.; Investigation of climatic forcing indicates that previous suggestions of climate processes are oversimplified. A preliminary study of climatic patterns suggests that glacier nourishment is from two sources: middle tropospheric system influences upper neves and the Aleutian Low influences elevations below 2,000 m. The Fairweather Range forms a barrier that causes storms moving off the Gulf of Alaska to deflect towards Cross Sound, causing a southerly introduction of moisture into Glacier Bay.; Recent termini fluctuations have been influenced by fjord geometry, morainal bank sedimentation, and iceberg calving. Grand Pacific Glacier exhibits the lowest mass balance indices observed; however, it has overridden its morainal bank in response to changes in tributary ice flux. Margerie Glacier advance has been limited by sediment dynamics beyond the sill of its trough despite a positive mass balance. Retreat of Muir Glacier into a narrow segment of Muir Inlet has allowed the ice flux to balance the calving flux, forming a phase of quasi-stability that has been followed by the most rapid period of fjord infilling ever monitored.; Glacial debris fluxes in GBNPP are among the highest ever recorded, with erosion rates ranging from 40.5 to 113.8 mm/yr. Glacial debris flux is controlled by glacier flux rates, valley geometry, bedrock and weathering state, substrate, and glacier thermal regime. Glacifluvial sediment production comprises 83.6 to 98.6% of the total glacial sediment production.; A sedimentary process hierarchy was determined by monitoring sediment volumes. Glacifluvial dumping and mass movements are first-order processes that add or remove {dollar}rm 10sp{lcub}6-7{rcub} msp3{dollar}/yr of sediment. Second-order processes (squeeze/push and plume settling), third-order process (conveyor-belt recycling), and fourth-order processes (calve dumping and ice-cliff meltout) introduce {dollar}rm 10sp{lcub}5-6{rcub}, 10sp{lcub}4-5{rcub}, 10sp{lcub}3-4{rcub} msp3{dollar}/yr, respectively. Processes which cause morainal bank aggradation (all except mass movements) reduce grounding-line water depth and form a positive feedback on terminus stability. |
