_version_ 1867169495803494400
author Wagenbach, Dietmar
Graf, Wolfgang
Minikin, Andreas
Trefzer, Ulrich
Kipfstuhl, Sepp
Oerter, Hans
Blindow, Norbert
author_facet Wagenbach, Dietmar
Graf, Wolfgang
Minikin, Andreas
Trefzer, Ulrich
Kipfstuhl, Sepp
Oerter, Hans
Blindow, Norbert
collection Datos científicos de ciencias marinas y ambientales
contents The ice cap on Berkner Island is grounded on bedrock within the Filchner-Ronne Ice Shelf and is, therefore, expected to be a well-suited place to retrieve long-term ice-core records reflecting the environmental situation of the Weddell Sea region. Shallow firn cores were drilled to 11 m at the two main summits of Berkner Island and analysed in high depth resolution for electrical d.c. conductivity (ECM), stable isotopes, chloride, sulphate, nitrate and methane-sulphonate (MSA). From the annual layering of dD and non-sea-salt (nss) sulphate, a mean annual snow accumulation of 26.6 cm water at the north dome and 17.4 cm water at the south dome are obtained. As a result of ineffective wind scouring indicated by a relatively low near-surface snow density, regular annual cycles are found for all species at least in the upper 4-5 m. Post depositional changes are responsible for a substantial decrease of the seasonal dD and nitrate amplitude as well as for considerable migration of the MSA signal operating below a depth of 3-4 m. The mean chemical and isotopic firn properties at the south dome correspond to the situation on the Filchner-Ronne Ice shelf at a comparable distance to the coast, whereas the north dome is found to be more influenced by maritime air masses. Persistent high sea-salt levels in winter snow at Berkner Island heavily obscure the determination of nss sulphate probably due to sulphate fractionation in the Antartic sea-salt aerosols. Estimated time-scales predict ages at 400 m depth to be ca. 2000 years for the north and ca. 3000 years for the south dome. Pleistocene ice is expected in the bottom 200 and 300 m, respectively.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_548752
institution PANGAEA
language en
publishDate 1994
publisher PANGAEA
record_format pangaea
spellingShingle Density and stable oxygen isotope profiles of four snow pits from Berkner Island, Filchner-Ronne Ice Shelf, Antarctica
Wagenbach, Dietmar
Graf, Wolfgang
Minikin, Andreas
Trefzer, Ulrich
Kipfstuhl, Sepp
Oerter, Hans
Blindow, Norbert
AWI_Glac; BER01C90_01; BER01S90_01; BER02C90_02; BER02S90_02; Berkner Island (Reinwarthhöhe); Berkner Island (Thyssenhöhe); FBIN North-dome; FBIS South-dome; Filchner-Ronne-Ice-Shelf-Project; FIRN; Firn auger; FRISP_1992; Glaciology @ AWI; Sampling/drilling ice; SNOWPIT; Snow pit; SSBerkN North-dome; SSBerkS South-dome
The ice cap on Berkner Island is grounded on bedrock within the Filchner-Ronne Ice Shelf and is, therefore, expected to be a well-suited place to retrieve long-term ice-core records reflecting the environmental situation of the Weddell Sea region. Shallow firn cores were drilled to 11 m at the two main summits of Berkner Island and analysed in high depth resolution for electrical d.c. conductivity (ECM), stable isotopes, chloride, sulphate, nitrate and methane-sulphonate (MSA). From the annual layering of dD and non-sea-salt (nss) sulphate, a mean annual snow accumulation of 26.6 cm water at the north dome and 17.4 cm water at the south dome are obtained. As a result of ineffective wind scouring indicated by a relatively low near-surface snow density, regular annual cycles are found for all species at least in the upper 4-5 m. Post depositional changes are responsible for a substantial decrease of the seasonal dD and nitrate amplitude as well as for considerable migration of the MSA signal operating below a depth of 3-4 m. The mean chemical and isotopic firn properties at the south dome correspond to the situation on the Filchner-Ronne Ice shelf at a comparable distance to the coast, whereas the north dome is found to be more influenced by maritime air masses. Persistent high sea-salt levels in winter snow at Berkner Island heavily obscure the determination of nss sulphate probably due to sulphate fractionation in the Antartic sea-salt aerosols. Estimated time-scales predict ages at 400 m depth to be ca. 2000 years for the north and ca. 3000 years for the south dome. Pleistocene ice is expected in the bottom 200 and 300 m, respectively.
title Density and stable oxygen isotope profiles of four snow pits from Berkner Island, Filchner-Ronne Ice Shelf, Antarctica
topic AWI_Glac; BER01C90_01; BER01S90_01; BER02C90_02; BER02S90_02; Berkner Island (Reinwarthhöhe); Berkner Island (Thyssenhöhe); FBIN North-dome; FBIS South-dome; Filchner-Ronne-Ice-Shelf-Project; FIRN; Firn auger; FRISP_1992; Glaciology @ AWI; Sampling/drilling ice; SNOWPIT; Snow pit; SSBerkN North-dome; SSBerkS South-dome
url https://doi.org/10.1594/PANGAEA.548752