Germany National Report
Prepared by Hans Oerter, AWA, Bremerhaven, Germany
email:
The German contribution to the ITASE programme was carried out during the last 5 years mainly in the frame of the EPICA presite survey in Dronning Maud Land along a traverse route from Neumayer Station (Ekstrˆmisen) across Ritscherflya and Kottasberge, Heimefrontfjella, to Amundsenisen (Table 1). The traverses were carried out by Alfred-Wegener-Institute for Polar- and Marine Research, Bremerhaven (AWI).
The field activities
(Table 2) comprise snow pit studies, shallow firn core drilling (10-40
m depth), medium deep ice core drilling (110-150 m depth), ground penetrating
radar measurements on Amundsenisen, and accumulation studies (stake readings)
along a profile line across Ritscherflya (Neumayer-Kottas Camp).
The 15 firn cores taken in the 1997/98 season on Amundsenisen (at DML03-DML23,
Table 1) cover at least the time period back to 1810 (Tambora 1815 and
an unknown volcanic event 1809 used as reference time markers). Three
ice cores (at DML05, DML07, DML17) cover even a period of almost 2000
years. All cores were analysed by DEP, gamma-attenuation density (fwilhelm@awi-bremerhaven.de),
and stable isotopes (18O and/or 2H). Isotope analysis
was done by AWI (hoerter@awi-bremerhaven.de) in cooperation with GSF-Institute
for Hydrology, M¸nchen-Neuherberg (wolfgang.graf@gsf.de). Four of
the cores were analysed so far for chemistry (hufischer@awi-bremerhaven.de)
as well.
At all location snow pits were analysed for density, stable isotopes and
chemistry, and partly radionuclides (10Be, 36Cl,
210Pb)
The published data will be made available through the PANGAEA data base (http://www.pangaea.de).
In cooperation with Jan-Gunnar Winther (Norsk Polar Institutt) and Rob Mulvaney (BAS) Hans Oerter (AWI) compiled the accumulation data available for Dronning Maud Land. A publication is in preparation.
The ground penetrating radar measurements were carried out with a RAMAC system at several frequencies between 50-800 MHz. The data are still under evaluation. One main focus of the interpretation is on the correlation between dielectric properties as measured in the firn cores (DEP) and radar reflexion horizons as well as the calculation of synthetic radargrams (oeisen@awi-bremerhaven.de, unixdorf@awi-bremerhaven.de).
Stake readings (hoerter@awi-bremerhaven.de) for accumulation studies across Ekströmsen and Ritscherflya was carried out each field seaon. The 460 km long stake line comprises approximately 950 stakes. It starts 10 km south of Neumayer at 70° 41.83'S, 8° 26.24'W and ends after the crossing of Kottasberge at 74° 30.00 S, 9° 13.09'W.
Glaciological work at the German wintering over base Neumayer is ongoing. It comprises snow pit studies, stake readings for accumulation studies and sampling of freshly fallen snow. The snow and firn samples are analysed with respect to stable isotopes (18O and/or 2H) and chemistry.
At the EPICA deep drilling site (Kohnen station) aerosol sampling was initiated in the 1999/2000 season by University of Heidelberg (Dietmar.Wagenbach@iup.uni-heidelberg.de) in cooperation with AWI (rweller@awi-bremerhaven.de). So far it is limited to the time when the base is in operation for drilling (Mid December - beginning February). There are plans for a year round sampling in the future.
In the reporting period there were no more glaciological activities on the Filchner-Ronne-Schelfeis due to the fact that the German summer base Filchner was floating away in 1998 on a huge iceberg and that AWI logistics are needed for EPICA in Dronning Maud Land. The last work done on the Filchner-Ronne-Schelfeis was compiled by Graf et al. (1999) and Lambrecht et al. (1999).
Publications:
Eisen, O., Nixdorf,
U., Wilhelms, F., Miller, H. (in press). Electromagnetic wave speed in
polar ice: Validation of the CMP technique with high resolution dielectric-profiling
and gamma-density measurements, Annals of Glaciology 34.
Eisen, O., Wilhelms, F., Nixdorf, U., Miller, H. (submitted). Identifying
isochrones in GPR profiles from DEP-based forward modeling. Annals of
Glaciology
Göktas, F., H. Fischer, S. Sommer, H. Oerter, H. Miller, R. Weller
(in press): A glacio-chemical characterisation of the new EPICA deep drilling
site on Amundsenisen, Dronning Maud Land, Antarctica. Annals of Glaciology
35
Göktas, F. (in press): Characterisation of glacio-chemical and glacio-meteorological
parameters of Amundsenisen, Dronning Maud Land, Antarctica. Dissertation
University of Bremen, Ber. Polar- und Meeresforschung, Bremerhaven.
Göktas, F., H. Oerter, H. Fischer, H. Miller, R. Weller, W. Graf
(submitted): Spatial variability and chronology of volcanic signals for
the past 2 kyr from Amundsenisen, Dronning Maud Land, Antarctica, J. Geophys.
Res.
Graf, W., Oerter, H., Mayer, C., Lambrecht, A.: Surface Accumulation on
Foundation ice stream, Antarctica. Annals of Glaciology 29, 23-28 (1999)
Graf, W., H. Oerter, O. Reinwarth, W. Stichler, F. Wilhelms, H. Miller,
R. Mulvaney (in press): Stable Isotope Records from Dronning Maud Land,
Antarctica. Annals of Glaciology 35
Lambrecht, A., Mayer, C., Nixdorf, U., Oerter, H.: Investigations to the
mass balance of the Ronne Ice shelf, Antarctica. Annals of Glaciology
29, 250-254 (1999)
Oerter, H., Wilhelms, F., Jung-Rothenhäusler, F., Göktas, F.,
Miller, H., Graf, W.,.Sommer, S. (2000): Accumulation rates in Dronning
Maud Land as revealed by, DEP measurements at shallow firn cores. Annals
of Glaciology 30, 27-34
Oerter, H., Graf, W., Wilhelms, F., Miller, H. (1999): Accumulation studies
on Amundsenisen, Dronning Maud Land, by means of tritium, DEP and stable
isotope measurements: first results from the 1995/96 and 1996/97 field
seasons. Annals of Glaciology 29, 1-9
Sommer, S., C. Appenzeller, R. Räthlisberger, M.A. Hutterli, B. Stauffer,
D. Wagenbach, H. Oerter, F. Wilhelms, H. Miller, and R. Mulvaney: Glacio-chemical
study spanning the past 2 kyr on three ice cores from Dronning Maud Land,
Antarctica 1. Annually resolved accumulation rates, J. Geophys. Res. 105
(D24), 29411-29421 (2000)
Schlosser, E., Oerter, H., Graf, W. (1999): Snow accumulation on Ekströmisen,
Antarctica, 1980-1996. Berichte zur Polarforschung 313, Bremerhaven,137pp.
Schlosser, E. and H. Oerter (in press): Shallow firn cores from Neumayer,
Ekströmisen – A comparison of dating methods, accumulation
rates, and stable isotope ratios. Annals of Glaciology 35
Schlosser, E., van Lipzig, N., Oerter, H. (in press): Temporal variability
of accumulation at Neumayer Station, Antarctica, from stake array measurements
and a regional atmospheric model, Journal of Glaciology
Table 1: Traverseroute from Neumayer Station (Ekströmisen) across Ritscherflya and Kottasberge, Heimefrontfjella, to Amundsenisen
Locality | Latitude | Longitude | Elevation, orthom.[m a.s.l.] | ||
Neumayer | 70° | 42.40'S | 8° | 25.6'W | 45 |
Kottas Camp | 74° | 12.30'S | 9° | 44.50'W | 1439 |
DML11 | 74° | 51.28'S | 8° | 29.82'W | 2600 |
DML18 | 75° | 15.02'S | 6° | 00.00'W | 2630 |
DML07 | 75° | 34.89'S | 3° | 25.82'W | 2669 |
DML19 | 75° | 10.04'S | 0° | 59.70'W | 2840 |
DML05 (Kohnen) | 75° | 00.14'S | 0° | 00.42'E | 2882 |
DML20 | 74° | 45.04'S | 0° | 59.99'E | 2860 |
DML03 | 74° | 29.95'S | 1° | 57.65'E | 2843 |
DML21 | 74° | 40.03'S | 4° | 00.10'E | 2980 |
DML22 | 75° | 05.04'S | 6° | 30.00'E | 3160 |
DML17 | 75° | 10.02'S | 6° | 29.91'E | 3160 |
DML23 | 75° | 15.05'S | 6° | 30.10'E | 3160 |
DML16 | 75° | 10.04'S | 5° | 00.20'E | 3100 |
DML15 | 75° | 05.02'S | 2° | 30.06'E | 2970 |
DML14 | 74° | 56.95'S | 1° | 29.67'W | 2840 |
DML13 | 75° | 00.00'S | 4° | 29.78'W | 2740 |
DML12 | 75° | 00.04'S | 6° | 29.90'W | 2680 |
DML11 | 74° | 51.28'S | 8° | 29.82'W | 2600 |
Table 2: Time schedule for traverse activities and measurements carried out
Season | Activity | Data | Publication |
1997/1998 | traverse from Neumayer towards Amundsenisen with 18 snow pits, 15 firn cores and 3 ice cores B31, B32, B33 (110-150 m deep) stake reading | density, 18O, 2H accumulation MSA, SO42-, Cl-, NO3-, Na+, NH4+ DEP, CFA | Oerter
et al., 2000 Sommer et al., 2000 Graf et al., in press Göktas et al., in press a Göktas et al., in press b Göktas et al. subm. |
1998/1999 | traverse from Neumayer towards Amundsenisen with GPR on Amundsenisen (DML11-DML07-DML05-DML03-DML17-DML05-DML11) stake reading | radar measurements | |
1999/2000 | traverse from Neumayer to DML05 (Kohnen) with snow pits and 3 shallow drillings in the surrounding of Kohnen stake reading | density, 18O, 2H accumulation MSA, SO42-, Cl-, NO3-, Na+, NH4+, 10Be, 36Cl, 210Pb, DEP | Göktas
et al., in press a Göktas et al., in press b Göktas et al. subm |
2000/2001 | traverse from Neumayer to DML05 (Kohnen) with GPR in the surrounding of Kohnen and between DML05 and DML07 stake reading | radar measurements accumulation | Eisen
et al., in press Eisen et al., subm. |
2001/02 | traverse from Neumayer to DML05 (Kohnen) with stake reading only | accumulation |
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