The geophysical observatory at Neumayer Station III fulfils three important tasks: its network of seismometers records where in the world there was a quake, and when; its infrasound sensors help to monitor global compliance with the nuclear test ban; and in the geomagnetic observatory researchers can explore how the Earth’s magnetic field changes with time – quite a bit of work to do, which is why every year two researchers overwinter at the station.
When there is an earthquake somewhere on the planet, the seismometers in the Neumayer Station III’s geophysical observatory record the acoustic waves produced by the natural phenomenon, depending on its intensity and location – just like they do when an “icequake” rocks the Ekström Ice Shelf, which the station rests atop, or the general vicinity. The extensive network of high-sensitivity motion sensors hardly misses a thing.
The seismic detection network includes:
Data produced at the Neumayer Station III’s seismographic network is constantly relayed to the AWI in Bremerhaven, and subsequently to the GEOFON Data Center at the GFZ Potsdam, where they are archived and made accessible online. The manually selected arrival times of all locally and globally detected earthquakes are sent to the International Seismological Centre (ISC) on a daily basis.
The Earthquake Monitor shows where in the world the Earth shook, when and how intensively.
To make measurements of the Earth’s magnetic field, geophysicists from the overwintering team have to descend 13 metres into the ice. A narrow access shaft leads down to the geophysical observatory, where a nonferrous measuring container lies protected from the influences of storms and snows.
The container houses three constantly operating magnetometers and a declinometer, which allow the researchers to determine the current orientation of our planet’s magnetic field in intervals of only a few days.
On the basis of the field’s strength, the scientists can e.g. identify magnetic storms – which can be especially interesting in the short-term, as they produce the legendary Southern Lights, offering a spectacular view on clear nights.
In the long term these regularly collected measurements will make it possible to closely monitor global changes in the magnetic field. Accordingly, they are also forwarded to an international information network, ensuring they are available to interested scientists around the globe.
Unfortunately, no camera can capture what goes on inside the geomagnetic recording devices. So our photographer instead chose to focus on accompanying our geophysicist Antje Schlömer as she makes their way to the geomagnetic observatory and when she takes the actual measurements in the ice – which can be quite an adventurous undertaking when conditions grow stormy.
Neumayer Station III’s infrasound measuring station, technically designated I27DE, is one of 60 stations in the worldwide network that monitors compliance with the Comprehensive Nuclear Test-Ban Treaty (CTBT). It can record shockwaves below the audible frequency range; produced by explosions or other natural or artificial events in the atmosphere, these waves can travel great distances, even reaching the Antarctic.
The station is located roughly three kilometres southwest of Neumayer Station III and consists of nine measuring sites, arranged in a spiral formation in a radius of ca. 1,000 metres around the central station. The station is operated by Germany’s Federal Institute for Geosciences and Natural Resources (BGR). Tech support is provided by the geophysicists at the Neumayer Station III, and by the BGR’s own technicians, who travel to the research station to carry out maintenance work in the Antarctic summer.
The measurement data is constantly transmitted to the CTBTO’s International Data Centre (IDC) in Vienna and the National Data Centre (NDC) in Hannover with only a few seconds’ delay.