Accumulation and stable-isotope studies at Kohnen station, Dronning Maud Land, Antarctica, from 1999 through 2011

• Main Author: Oerter, Hans
• Format: Conference Object
• Language: unknown
• Published: 2013
• Subjects: Antarc*; Antarctica; Dronning Maud Land; EPICA; ice core; Polarforschung
• Online Access: https://epic.awi.de/id/eprint/32779/; https://epic.awi.de/id/eprint/32779/1/Polartg_Hbg__SNOWPITS_oerter.pdf; https://hdl.handle.net/10013/epic.41350; https://hdl.handle.net/10013/epic.41350.d001

The area of the later Kohnen station (75°00’06”S, 0°04’04”E) in Dronning Maud Land, Antarctica, was visited the first time during the EPICA-pre site survey in the austral summer 1997/98. In 1999/2000 the construction of the base started. At the same time a glaciological programme was initiated to study snow accumulation and stable isotopes in the surroundings of the base and the site of the EDML ice core, respectively. The data of 20 snow pits cover the period 1986-2010. The pits had been sampled with a depth resolution between 1.5cm and 5cm. Linear fits through the time series do not show a significant trend neither for accumulation nor δ18O content. However, for the year 2008 an outstanding high accumulation rate was found in all 6 snow pits which were digged in January 2011. The average δ18O content and mean accumulation rate for the period 1259-1816 from 4 nearby firn cores (B32, B34, B37 and EDML) is -45.01 ‰-SMOW and 62.3 kg m-2 a-1, respectively. Both the mean annual isotope content and the mean annual accumulation rate during the past 25 years are above the long term average. They display values of -44.00 ±1.07 ‰-SMOW and 72.5 ±11.2 kg m-2 a-1 respectively. Thus, the results of the snow pit studies fit into the general pattern of increasing accumulation rates and increasing stable-isotope contents of snow during the 20th century.