Meltwater circulation and permeability of Arctic summer ice derived from hydrological field experiments

ABSTRACT. Permeability and meltwater flow have been studied in sea ice in the Siberian and central Arctic during the summers of 1995 and 1996. A bail-test technique has been adapted to allow for measurements of in situ permeability, found to range between 10^11 and 10^8 m2. Permeability varied by ab...

Full description

Bibliographic Details
Main Authors: Johannes Freitag, Hajo Eicken
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Published: 2003
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.510.4943
http://www2.gi.alaska.edu/~eicken/he_publ/03FE.pdf
Description
Summary:ABSTRACT. Permeability and meltwater flow have been studied in sea ice in the Siberian and central Arctic during the summers of 1995 and 1996. A bail-test technique has been adapted to allow for measurements of in situ permeability, found to range between 10^11 and 10^8 m2. Permeability varied by about a factor of 2 between 1995 (above-normalmelt rates) and1996 (below-normalmelt rates). Release of fluorescent tra-cers (fluorescein, rhodamine) furthermore allowed the derivation of flow velocities and assessment of the relevant driving forces. Hydraulic gradients in rough ice andwind stress in ponded ice were found to be particularly important, driving meltwater over distances of several meters per day.The mid- to late-summer ice was found to be permeable enough to completely divert meltwater from the surface into the ice interior. It is shown, however, that lower permeabilities of the upper ice layers as well as refreezing of meltwater, par-ticularly during the early melt season, foster the development of surface melt ponds.