Snow-stake measurements in the surroundings of the Georg von Neumayer and Neumayer II stations during the years 1982-2008

• Main Authors: Oerter, Hans, Kipfstuhl, Sepp, Meyer, Hanno
• Format: Conference Object
• Language: unknown
• Published: 2010
• Subjects: Neumayer; Polarforschung
• Online Access: https://epic.awi.de/id/eprint/22498/; https://epic.awi.de/id/eprint/22498/1/Oer2010e.pdf; https://hdl.handle.net/10013/epic.34894; https://hdl.handle.net/10013/epic.34894.d001

Snow accumulation in the surroundings of the two wintering-over bases Georg-von-Neumayer (GvN, 1981-1992) and Neumayer II (1992-2009) was determined by means of two stake arrays. These arrays have been maintained by the meteorologists who wintered over at the Neumayer stations. One of the stake arrays was located close to the base and therefore it was possible to make weekly stake readings. In 1991 another stake array was established 15 km south of the base GvN. Since then it was not relocated. It has been visited once in a month for stake readings. The density values needed to calculate accumulation rates from stake readings were taken from snow pit studies. Usually a density value of 350 kg/m3 was used. This value may be discussed. In addition, the results of two shallow firn cores were available for comparison with the stake read-ings. The first firn core was drilled on Dec. 12, 1989 approximately at that location (70.658610° S, 8.25250° W), where it was planned to construct the Neumayer II station two years later. The core contains the annual snow layers from 1975-1988. The second firn core was drilled on Jan. 03, 2002 adjacent to the stake array of the Neumayer II station at 70.655700° S, 8.25363° W. This core contains the annual layers from 1980-2001. The firn cores were mainly dated by means of the seasonal cycles of the content of the stable isotope 18O.The paper compares the data resulting from the three stake arrays with the accumulation data from the firn cores. The absolute values of the different time series differ from each other. How-ever, in the coinciding periods the patterns are very similar. It is remarkable, that in the period 1980-1994 all time series show declining accumulation rates. For the period in which Neumayer II had been in operation no trend of the accumulation rates can be seen. Only strong interannual variations can be observed.For the three stake arrays the following annual mean values and standard deviations were found: stake array GvN (1982-1992) 277 ±52 kg m-2 a-1, stake array Neumayer-II (1993-2008) 235 ±84 kg m-2 a-1 and stake array South (1991-2008) 320 ±122 kg m-2 a-1. The firn core from 2002 (1980-2001) yields a value of 329 ±109 kg m-2 a-1 and the firn core from 1989 (1975-1988) a value of 353 ±109 kg m-2 a-1. It can be observed that the accumulation rates are lower in the sur-roundings of the bases than at the array located further south and at greater distance to the coast. In addition, the values calculated by means of stake readings are lower than those calculated from firn cores.