Closer look: Ice cores – a time capsule of the Earth’s climate
Did you know that researchers can trace our planet’s climate back hundreds of thousands of years? The secret lies in ice cores: long, cylindrical samples taken from glaciers and ice masses.
The image explained by Professor Mark Peternell:
"This is a microscopy image of a ~1mm thick ice slide, taken from a lake ice core. The cut is parallel to the core long axis, and you can nicely see different ice crystals, and at the bottom one very large one. The colors of the crystals are related to their crystallographic orientation in the section. What is very nice is that there is a higher concentration of air bubbles arranged in a layer in the center of the image."
These ice cores act as a kind of time capsule, in which layer upon layer of ice has been formed by snow having fallen and been compressed. In this way, tiny air bubbles, mineral particles and other materials from each time period have been preserved. By drilling deep into the ice and analysing these samples, researchers can gain a unique insight into the Earth’s past climate and atmosphere.
One of the main reasons why researchers study ice cores is to get a better understanding of our own impact on the climate. Ice cores contain traces of greenhouse gases – such as carbon dioxide and methane – from previous millennia. As well as microplastics. At the University of Gothenburg, a research team led by Dr Mark Peternell studies ice cores from the Vatnajökull glacier in Iceland. They have found microplastic particles of various sizes and materials. Microplastics in ice can affect glacier melt patterns, thereby influencing future meltwater contributions to the oceans. Conversely, melting glaciers can release large amounts of microplastics into our environment, and this is a danger to us all.
Read the research article here
Text: Erika Hoff
