Premium
Dynamic perennial firn aquifer on an Arctic glacier
Author(s) -
Christianson Knut,
Kohler Jack,
Alley Richard B.,
Nuth Christopher,
Pelt Ward J. J.
Publication year - 2015
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2014gl062806
Subject(s) - firn , geology , permafrost , glacier , snow , geomorphology , arctic , aquifer , ground penetrating radar , moraine , water table , hydrology (agriculture) , radar , groundwater , oceanography , telecommunications , geotechnical engineering , computer science
Ice‐penetrating radar and GPS observations reveal a perennial firn aquifer (PFA) on a Svalbard ice field, similar to those recently discovered in southeastern Greenland. A bright, widespread radar reflector separates relatively dry and water‐saturated firn. This surface, the phreatic firn water table, is deeper beneath local surface elevation maxima, shallower in surface lows, and steeper where the surface is steep. The reflector crosscuts snow stratigraphy; we use the apparent deflection of accumulation layers due to the higher dielectric permittivity below the water table to infer that the firn pore space becomes progressively more saturated as depth increases. Our observations indicate that PFAs respond rapidly (subannually) to surface forcing, and are capable of providing significant input to the englacial hydrology system.