Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Icebergs: Mathematical model calculates the collapse of shelf ice

24.08.2017

Shelf ice, as found in Antarctica, refers to giant floating ice sheets that can span thousands of square kilometres. Pieces break off at their edges which form icebergs in the ocean. In order to more effectively predict these break-offs, in a process known as calving, Julia Christmann from the University of Kaiserslautern (TU) has developed mathematical models in cooperation with the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI). On the basis of physical factors, it is claimed that these models can be used to predict when and where the ice may collapse. This is important particularly for research teams situated on the ice shelf.

The ice rises up like a sheer cliff face – shelf ice is not only several thousand square kilometres large, it is also more than a hundred metres high in many places. From time to time, pieces break off the edge and crash into the sea below, where they float away in the ocean as icebergs. This was also recently the case with the Larsen C ice shelf.


Julia Christmann in front of the icebreakter "Polarstern" in the Antarctica

Credit: Julia Christmann


Julia Christmann

Credit: Thomas Koziel

Science is unable to accurately predict when and where the ice shelf will break. “Assumptions were always previously based on observations by glaciologists and other researchers. Concrete calculations with physical parameters did not exist,” says Julia Christmann, who is researching technical mechanics at the University of Kaiserslautern with Professor Dr Ralf Müller. As a rule of thumb, she explains, the ice tends to break where it is thinner than 200 metres; in reality, however, there are also many ice shelves that are even thinner.

The calving of ice sheets is a continuous process that is influenced by a number of different factors. Satellite data was also used in order to observe this natural spectacle. “However, they only offer snapshots of the process,” Christmann adds. As part of her doctorate research, she has developed mathematical models to calculate when and where the ice shelf may collapse. A range of different physical factors are germane here.

“The thickness and density of ice can play an important role, for example,” Christmann continues. “The material parameters are also critical, including elastic factors. These mainly influence where the iceberg is calved. There is also the viscosity, which affects the time between break-off events.”

The doctoral student at Kaiserslautern was also supported in her work by Professor Dr Angelika Humbert from the AWI. Humbert is an expert in the field of glaciology. She is also occupied with the properties and motion of giant ice sheets on the Antarctic continent, which constitute 70 percent of the entire supply of freshwater on the planet.

“The ice shelf generally breaks at points that are between a half and full thickness of the ice sheet from the edge,” summarises Christmann. This data may be particularly important for the scientific community, since numerous research stations are located on ice shelves in Antarctica. This includes the German Neumayer Station III or the British station, Halley VI, which was closed for winter this year due to a crack in the ice.

Christmann recently completed her doctoral thesis. She is continuing her research on the properties of ice. She is now focusing on grounding lines in Greenland. This refers to the area in which the ice still touches the ground and merges into floating shelf ice. The researcher intends to find out how these lines change over the course of time.

For enquiries:
Dr Julia Christmann
Technical Mechanics
TU Kaiserslautern
Tel.: 0631 205-2126
Email: jchristm[at]rhrk.uni-kl.de

Melanie Löw | Technische Universität Kaiserslautern
Further information:
http://www.uni-kl.de

More articles from Earth Sciences:

nachricht Atmospheric scientists reveal the effect of sea-ice loss on Arctic warming
11.03.2019 | Institute of Atmospheric Physics, Chinese Academy of Sciences

nachricht Sensing shakes
11.03.2019 | University of Tokyo

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Revealing the secret of the vacuum for the first time

New research group at the University of Jena combines theory and experiment to demonstrate for the first time certain physical processes in a quantum vacuum

For most people, a vacuum is an empty space. Quantum physics, on the other hand, assumes that even in this lowest-energy state, particles and antiparticles...

Im Focus: Sussex scientists one step closer to a clock that could replace GPS and Galileo

Physicists in the EPic Lab at University of Sussex make crucial development in global race to develop a portable atomic clock

Scientists in the Emergent Photonics Lab (EPic Lab) at the University of Sussex have made a breakthrough to a crucial element of an atomic clock - devices...

Im Focus: Sensing shakes

A new way to sense earthquakes could help improve early warning systems

Every year earthquakes worldwide claim hundreds or even thousands of lives. Forewarning allows people to head for safety and a matter of seconds could spell...

Im Focus: A thermo-sensor for magnetic bits

New concept for energy-efficient data processing technology

Scientists of the Department of Physics at the University of Hamburg, Germany, detected the magnetic states of atoms on a surface using only heat. The...

Im Focus: The moiré patterns of three layers change the electronic properties of graphene

Combining an atomically thin graphene and a boron nitride layer at a slightly rotated angle changes their electrical properties. Physicists at the University of Basel have now shown for the first time the combination with a third layer can result in new material properties also in a three-layer sandwich of carbon and boron nitride. This significantly increases the number of potential synthetic materials, report the researchers in the scientific journal Nano Letters.

Last year, researchers in the US caused a big stir when they showed that rotating two stacked graphene layers by a “magical” angle of 1.1 degrees turns...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Researchers measure near-perfect performance in low-cost semiconductors

18.03.2019 | Power and Electrical Engineering

Nanocrystal 'factory' could revolutionize quantum dot manufacturing

18.03.2019 | Materials Sciences

Long-distance quantum information exchange -- success at the nanoscale

18.03.2019 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>