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  • Thumbnail for An Examination of Controls on Moulin Microclimatology, Kennicott and Root Glaciers, Alaska
    An Examination of Controls on Moulin Microclimatology, Kennicott and Root Glaciers, Alaska by Keskinen, Zachary Marshall

    Moulins are a crucial but poorly understood aspect of the glacial hydrological system, providing a channel for proglacial meltwater to drain into englacial conduits. This project examined moulin microclimatology utilizing 16 temperature data loggers emplaced in 7 moulins on the Root and Kennicott Glaciers, Alaska, from June 22nd to July 17th, 2015. These loggers were attached to the walls of the moulin and recorded air temperature every 16 minutes. Using this data set, the project examined the depth of penetration, timing, and magnitude of diurnal temperature fluctuations within moulins on a temperate glacier. Diurnal temperature variations penetrated to depths up to 10 meters into the moulins, with the magnitude of variation generally decreasing with increasing depth. Sensors close to the ice surface recorded temperature peaks in the early afternoon, while deeper sensors (3+ meters) had weak diurnal peaks between 4-8 am. Additionally, this project examined correlations between external weather characteristics (ambient temperatures, incoming shortwave radiation, wind speeds, and precipitation) and internal moulin temperatures. Shortwave radiation had the highest correlation to moulin temperatures (r2= 0.6-0.8), with weaker correlation between external temperature and moulin temperature (r2= 0.2-0.3). No significant correlation was found between wind speeds, rain, and moulin temperatures. Finally the data were analyzed to identify lag periods between changes in ambient temperature and correlated swings in moulin temperatures. My deepest sensors (>6 meters) seemed to have a lag period of between 3 and 8 hours compared to ambient temperature peaks.