German flag Germany National Report
Prepared by Hans Oerter, AWA, Bremerhaven, Germany
email: hoerter@awi-bremerhaven.de

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 25.6'W 45
Kottas Camp 74° 12.30'S 44.50'W 1439
DML11 74° 51.28'S 29.82'W 2600
DML18 75° 15.02'S 00.00'W 2630
DML07 75° 34.89'S 25.82'W 2669
DML19 75° 10.04'S 59.70'W 2840
DML05 (Kohnen) 75° 00.14'S 00.42'E 2882
DML20 74° 45.04'S 59.99'E 2860
DML03 74° 29.95'S 57.65'E 2843
DML21 74° 40.03'S 00.10'E 2980
DML22 75° 05.04'S 30.00'E 3160
DML17 75° 10.02'S 29.91'E 3160
DML23 75° 15.05'S 30.10'E 3160
DML16 75° 10.04'S 00.20'E 3100
DML15 75° 05.02'S 30.06'E 2970
DML14 74° 56.95'S 29.67'W 2840
DML13 75° 00.00'S 29.78'W 2740
DML12 75° 00.04'S 29.90'W 2680
DML11 74° 51.28'S 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

Appendix:

Dronning Maud Land graphic