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Future sea-level predictions require that the history of the Antarctic Ice Sheet is well understood and constrained by observations. Much of the ice sheets’ ice-dynamic properties are governed by processes at the ice-bed interface which can be imaged with radar sounding surveys. Here we use a combination of ultra-wideband radio-echo sounding data, satellite radar and laser altimetry data, as well as electromagnetic waveform modeling to characterize the properties of the ice base and the evolution of the subglacial morphology of the Jutulstraumen drainage basin (western Dronning Maud Land, Antarctica). Based on the classification of the bed topography, we reconstruct the step-by-step modifications the subglacial landscape has experienced since the beginning of the glaciation of Antarctica, 34 million years ago. Between 2017 and 2020, we find evidence of active episodic cascade-like subglacial water transport along the subglacial valley network. In addition, our high-resolution radio-echo sounding data reveal a cluster of anomalous basal ice units whose material properties we constrain by electromagnetic waveform modeling. Through this, we aim to derive the physical conditions at the ice base, and establish a link to the subglacial hydrology system. The combination of these observations will represent an important step towards a better understanding of large-scale ice-sheet dynamics in western Dronning Maud Land.

Passive seismic measurements allow the study of the deeper Earth beneath the thick Antarctic ice sheet cover. Due to logistical and weather constraints, only a fraction of the area of the Antarctic ice sheet can be surveyed with long-term or temporary sensors. A fundamental limitation is the power supply and operation of the instruments during the polar winter. In addition, there is only a limited time window during the field seasons to deploy the stations over the year. Here we present a rapidly and simple deployable self-sufficient mobile seismic station concept. The station consists of different energy supply modules aligned according to the survey needs, measuring duration, and survey aim. Parts of the concept are integrated into an already existing pool of mobile stations and in the seismological network of the geophysical observatory at Neumayer III Station. Other concepts and features are still under development. The overall goal is to use these temporary mobile arrays in regions where little is known about local and regional tectonic earthquake activity.

Future sea-level predictions require that the history and physical state of the Antarctic ice sheet is well understood and constrained by observations. Much of the ice sheets’ ice-dynamic properties are governed by processes at the ice-bed interface which can be imaged with radar sounding surveys. Moreover, certain processes at the ice-sheet base can have an effect all the way to the ice surface, which in turn can be observed with satellites. Here we use a combination of ultra-wideband radio-echo sounding data, satellite radar and laser altimetry data to characterize the evolution of the subglacial morphology of the Jutulstraumen drainage basin (western Dronning Maud Land, Antarctica). Based on the classification of the bed topography, we reconstruct the step-by-step modifications the subglacial landscape has experienced since the beginning of the glaciation of Antarctica, 34 million years ago. In addition, between 2017 and 2020, we find evidence of active episodic cascade-like subglacial water transport along the subglacial valley network. The combination of these observations will represent an important step towards a better understanding of large-scale ice-sheet dynamics in western Dronning Maud Land.

Germany has been operating permanently crewed research stations in Antarctica for more than 45 years. The opening of the Georg Forster Station (1976) and Georg von Neumayer Station (1981) initiated a period of continuous environmental monitoring that allowed both the former East Germany and West Germany to become contracting parties in, and achieve consultative status with, the framework of the Antarctic Treaty. This marked a milestone in German polar research. Continuous research at the Neumayer Station III, its two predecessors, and the now-dismantled former German Democratic Republic (GDR) Georg Forster Station is undertaken by teams of so-called “overwinterers”, presently with nine members, who stay at the base for longer than an entire Antarctic winter. Their long-term stay in Antarctica is defined by isolation, separation from civilization, routine work to sustain long-term scientific observations, and unique personal experiences. This article is dedicated to them and outlines their part and role in the German Antarctic research landscape.

The landscape of Antarctica, hidden beneath kilometre-thick ice in most places, has been shaped by the interactions between tectonic and erosional processes. The flow dynamics of the thick ice cover deepened pre-formed topographic depressions by glacial erosion, but also preserved the subglacial landscapes in regions with moderate to slow ice flow. Mapping the spatial variability of these structures provides the basis for reconstruction of the evolution of subglacial morphology. This study focuses on the Jutulstraumen Glacier drainage system in Dronning Maud Land, East Antarctica. The Jutulstraumen Glacier reaches the ocean via the Jutulstraumen Graben, which is the only significant passage for draining the East Antarctic Ice Sheet through the western part of the Dronning Maud Land mountain chain. We acquired new bed topography data during an airborne radar campaign in the region upstream of the Jutulstraumen Graben to characterise the source area of the glacier. The new data show a deep relief to be generally under-represented in available bed topography compilations. Our analysis of the bed topography, valley characteristics and bed roughness leads to the conclusion that much more of the alpine landscape that would have formed prior to the Antarctic Ice Sheet is preserved than previously anticipated. We identify an active and deeply eroded U-shaped valley network next to largely preserved passive fluvial and glacial modified landscapes. Based on the landscape classification, we reconstruct the temporal sequence by which ice flow modified the topography since the beginning of the glaciation of Antarctica.

VNA (IAGA code) is the geomagnetic observatory of the German Antarctic research station Neumayer III located on the Ekström ice shelf at 70.7° S and 351.7° E. The station is the currently the only permanent station in Antarctica situated on an ice shelf and as such it raises unique challenges for geomagnetic data acquisition. The station, along with the ice shelf, drifts by 157 m per year to the north and rotates clockwise by 0.25° per year. But high-quality, absolutely calibrated geomagnetic field vector data depend on precise knowledge of the geodetic reference frame and – for the study of secular variation – stable conditions, especially with respect to artificial or crustal fields at the observatory. Here, we present the observatory and our approach to compensate for the observatory's movements for obtaining both near real-time and definitive geomagnetic observatory data. First, the azimuth of the azimuth mark has to be determined and updated regularly, as it also rotates with the ice. The observatory is located in an underground ice cave and therefore celestial objects cannot serve as a fixed reference and instead, the azimuth is determined on a monthly basis by a north-seeking gyro. Second, due to its northward drift, the observatory is moving across a significant gradient of the crustal magnetic field observed first in aeromagnetic surveys over the region as well as in ground profiles of total field strength along the drift path. This results in a temporal change of the crustal bias of approx. 10 nT per year. Based on the observatory data alone, this signal cannot be separated from the secular variation of the core field. In order to correct the observatory time series for this change in crustal bias, vector absolute measurements were performed along the drift path in austral summer 2016/2017. Additionally, the aeromagnetic data was downward continued to obtain the vector field along the drift path of the observatory. In the austral summer 2017/18, the obser

The new knowledge and data portal ‘meereisportal.de’ is a contribution to the cross-linking of scientifically qualified information on climate change. It focuses deliberately on the theme ‘sea ice in both Polar Regions’. With the establishment of ‘meereisportal.de’, science adapts to changing societal demands and embarks on new ways of communication between science and society.

We report on continuously measured 222Rn activity in near surface air at Neumayer Station in the period 1995 through 2011. This 17 years record showed no long-term trend and has overall mean ± standard deviation of (0.019±0.012) Bq m-3. A distinct and persistent seasonality could be distinguished with maximum values of (0.028±0.013) Bq m-3 from January through March and minimum values of (0.015±0.009) Bq m-3 from May through October. Elevated 222Rn activity concentrations were typically associated with air mass transport from the Antarctic Plateau. Our results do not support a relation between enhanced 222Rn activity concentrations at Neumayer and cyclonic activity or long-range transport from South America. The impact of oceanic 222Rn emissions could not be properly assessed but we tentatively identified regional SIE variability as a significant driver of the annual 222Rn cycle.

Antarctic sea-ice mass, -extent, and -properties are expected to experience significant changes in the next decades. Long-term and consistent time series of in-situ measurements are crucial to reveal insights into this system, and are needed to validate satellite derived sea-ice parameters and numerical simulations. Following the need for a coordinated approach on the monitoring of Antarctic landfast sea ice, the Antarctic Fast Ice Network (AFIN) was initiated as a legacy project during the 2007-2009 International Polar Year. As part of AFIN, a regular observation program was started in 2010 on the landfast sea ice of Atka Bay, in the northeastern Weddell Sea. The measurements are carried out by the German Antarctic station Neumayer III, situated on the Ekström Ice Shelf at 70◦40’S, 008◦16’W. This field report describes our measurement activities between June 2011 and January 2012, and presents some preliminary results.