Apr 03, 2026
Following the trace of the ice: How changes in the Southern Patagonian Ice Field can be measured
Setting up the FG5 absolute gravimeter at the Estancia Helsingfors measuring point
In early March 2026, scientists from Dresden University of Technology and the Federal Agency for Cartography and Geodesy (BKG) in Leipzig returned from a four-week measurement campaign in southern Patagonia (Argentina). They have brought back new measurement data, collected from the eastern edge of the Southern Patagonian Ice Field all the way to the Atlantic coast, which will help to provide insights into the shrinking of the ice masses.
Southern Patagonia is home to the largest ice masses in the southern hemisphere outside Antarctica: the Patagonian ice fields. Like other glaciers around the world, and even the two continental ice sheets in Greenland and Antarctica, the Patagonian ice fields are also losing mass at an increasing rate due to global warming.
Map showing the study area from the southern Patagonian Ice Field to the Atlantic coast, with the measurement points for absolute gravimetry.
To measure this ice-mass change, Mirko Scheinert from the Chair of Geodetic Earth System Research at TU Dresden and Axel Rülke from BKG Leipzig, as project leaders, are carrying out a joint research project funded by the German Research Foundation (DFG).
Alfredo Pasquare is setting up the FG5 absolute gravimeter for measurements in Puerto San Julian.
In 2026, the third measurement campaign was successfully completed, following those in 2020 and 2022. A short film provides a first impression of the fieldwork. Alongside the scientists André Gebauer and Erik Brachmann (BGK Leipzig) and the Master’s student Benjamin Göbel (TU Dresden), further colleagues from project partners in Argentina were involved: Alfredo Pasquare from the Argentine-German Geodetic Observatory (AGGO), which is also celebrating its 10th anniversary this year, Andreas Richter (Universidad Nacional de La Plata and TU Dresden), Eric Marderwald (Estación Astronómica de Río Grande) and Steffen Welsch (El Calafate).
Erik Brachmann during the FG5 measurement at Tres Lagos.
For their measurements, the scientists are using a particularly sensitive method: absolute gravimetry. Axel Rülke emphasises: “The FG-5 absolute gravimeter used here is capable of measuring the slightest changes in gravity. Gravitational acceleration, which is of the order of approximately 9.8 m/s², can thus be recorded to the eighth decimal digit.” The changes in gravity determined at eight points over a six-year period are also correlated with the changes in elevation measured at these points using GNSS (Global Navigation Satellite System).
Benjamin Göbel is carrying out relative gravity measurements using a Scintrex CG6 gravimeter to determine the local gravity gradient at the measuring station in El Calafate.
By combining these measurement methods, the aim is to gain a better understanding of the complex geoscientific situation in the region of the Southern Patagonian Ice Field: Changes in ice mass must be traced back from the present day over several thousand years into the past in order to understand the deformation of the Earth’s crust currently being measured by GNSS. The complex structure of the Earth’s interior in Patagonia plays a particular role here: with the Nazca, South American and Antarctic plates, three tectonic plates converge in the region, creating a unique situation.
The analysis of all measurement data from the three campaigns in 2020, 2022 and 2026 will provide a deeper scientific understanding of how the Southern Patagonian Ice Field responds to climate change and how it interacts with the solid Earth.
The research project “Gravimetric determination of the response of the solid Earth to changes in ice mass in South Patagonia” (GravPatagonia) is funded by the DFG (GZ. SCHE 1426/28-1 and RU 2380/1-1).
Joint press release of TU Dresden and BKG Leipzig.
Short video of the measurement campaign (trailer).
Contact:
Dr. Mirko Scheinert, TU Dresden, Chair of Geodetic Earth System Research, Helmholtzstr. 10, 01069 Dresden, Germany
Email: , Phone: 0351 463 33683
Dr. Axel Rülke, Federal Agency for Cartography and Geodesy, Department Satellite Navigation, Karl-Rothe-Straße 10-14, 04105 Leipzig, Germany
In the area of Estancia Christina, Benjamin Göbel is carrying out relative gravity measurements at an ex-centre).
GNSS reflectometry is used to determine the current water level of the ocean or the large lakes in order to obtain correction values for the analysis of absolute gravimetry. Andreas Richter has set up the GNSS measurement equipment in Puerto San Julian.
A view of the Perito Moreno Glacier, one of the largest glaciers in the Southern Patagonian Ice Field, which from time to time blocks the southern arm of Lake Argentino, causing it to back up.
Carrying out precise levelling to determine the height differences between the various measurement points (absolute gravimetry, GNSS, control points), here in the Estancia Cristina area. Andreas Richter, Eric Marderwald and Axel Rülke (from left to right)