A little ice age reconstruction for ice tongues of the Grewingk-Yalik ice complex, southern Kenai mountains, Alaska
Padington CH. 1993. A little ice age reconstruction for ice tongues of the Grewingk-Yalik ice complex, southern Kenai mountains, Alaska. State University of New York
Outlet valley glacier systems (drainage basins) of the Grewingk-Yalik Ice Complex, Kenai Mountains, have been differentiated and reconstructed to their Little Ice Age maxima (LIAmax) between 1200 A. D. and 1900 A. D. Field maps of ice marginal features and the resulting paleoglacier reconstructions show that glacier termini of the outlet tongues have retreated and average of 3000 m since their LIAmax. Total surface are loss on the ice field may have reached as much as 12 percent (35 km2). Application of flow law theory to the reconstructions and comparison with current maps (1988/1989) provide estimates of mass flux that have been reduced about 50 percent from the LIAmax. Little Ice Age maxima equilibrium-line altitudes (ELA) determined using an accumulation-area ration (AAR) of 0.75 have been compared with modern ELAs determined by extrapolation of transient firnlines on the glaciers. These data suggest that ELAs have been depressed 111 m to the present level since their LIAmax. Application of the local atmospheric lapse rate of 0.82 degrees C per 100 m indicates that average annual ablation season temperatures may have been about 1 degree C lower than present during the Little Ice Age. This is comparable with the temperature changes estimated from other areas of Alaska and world-wide averages.
- Type
- Academic
- Authors
- Padington, Clay
- Date of Issue
- 1993-01-22
- Publisher
- State University of New York
- Units
- KEFJ
- Keywords
- ELA, equilibrium line altitude, Glacial Processes, Glaciers, Grewingk Glacier, Grewingk-Yalik, Hydrology, Kenai Fjords National Park, Kenai Mountains, little ice age, mass flux, Thesis, Yalik Glacier