Spring and aufeis (icing) hydrology in Brooks Range, Alaska

Abstract

[1] Remote sensing studies and field hydrometeorological and geophysical investigations were employed to characterize several aufeis fields in the Brooks Range, Alaska. Geochemical studies were undertaken together with field hydrological measurements to better understand the chemical and thermal properties of stream base flow (groundwater spring) that contributes to winter aufeis development. The spring water temperature was measured at several major aufeis fields using data loggers throughout the year. Aufeis is an important water storage component in the Arctic and influences local ecology and geomorphology. Synthetic aperture radar (SAR) is a useful and sensitive sensor for aufeis detection and for estimating the total volume of storage as well as freeze/thaw conditions. The SAR analysis indicated that the volume of aufeis formed in winter is 27-30% of the annual groundwater discharge in the Kuparuk River. Visible and near-IR satellite imagery indicated many of the high-discharge springs (more than 10-1000 1/s) and aufeis fields are centered around an elevation of 600 m a.s.l. in limestone areas with glacial morphology. Geomorphological investigations indicate that many of springs have continually existed from at least the last glaciation. Microwave data (SAR), thermal infrared, short wave infrared, and visible and near-IR bands were all used to observe the growth, decay, and distribution of aufeis deposits. The remotely sensed data indicate that the distribution of the aufeis deposits today is nearly the same as it was in past colder periods; this was mainly determined by mapping the distributed carbonate precipitates. Also, spring water temperatures and discharge volumes are predictable from the aufeis field size using remotely sensed techniques.

Long-term variability of the spring taryn-aufeises

“…Итоги десятилетних режимных наблюдений (1996-2005 гг .) опубликованы в работе [45] . Для оценки многолетней изменчивости размеров ледяного массива мы представили полученные данные в процентах по отношению к максимальным зна чениям, зафиксированным в течение всего пе риода наблюдений (табл .…”

Overwintering Locations, Migrations, and Fidelity of Radio-Tagged Dolly Varden in the Hulahula River, Arctic National Wildlife Refuge, 2007–09

“…All surface flow ceases during winter, so aquatic habitat becomes limited to a few perennial springs (Craig and McCart, 1975;Childers et al, 1977;Kane et al, 2013). The springs have stable groundwater sources recharged by precipitation across porous limestone regions of the Brooks Range to the south (Hall and Roswell, 1981;Yoshikawa et al, 2007;Kane et al, 2013). Because of the stable groundwater flow during the extended winter season, aufeis areas develop downstream from each perennial spring, and the size or mass of each aufeis area is proportional to the flow volume of the associated spring.…”

A 14,500-year record of landscape change from Okpilak Lake, northeastern Brooks Range, northern Alaska

“…Aggradation might also be caused by hillslope erosion associated with rising soil moisture, thawing permafrost, or reduced vegetation cover (Mann et al 2002(Mann et al , 2010. Random lateral movements of the Okpilak River, or diversions of flow into subsidiary channels by aufeis (Yoshikawa et al 2007), may have resulted in the lake being more or less susceptible to these types of fluvial deposition at different times in the past. For example, if the main channel of the braided system happened to be closer to the east side of the Okpilak valley, the lake would have more easily received sediment during short-term floods or minor aggregational events.…”