Active dripstone formation in a side area of the “Kleine Teufelshöhle." Credit: KIT (taken as part of the HEiKA Project Check Extrema)
Key points:
- A research team used tree-ring record data and measurements from stalagmite – a dripstone that grows upward from the floor of a cave – to study climate fluctuations across hundreds of years.
- Researchers measured the composition of oxygen isotopes within stalagmite with an ion probe and aligned their data with environmental events.
- Scientists no longer have to rely exclusively on tree-ring records to study natural climate fluctuations as stalagmite can serve as a unique archive to accurately reconstruct regional and global climate history.
A research team used tree-ring record data and measurements from stalagmite—a dripstone that grows upward from the floor of a cave—to study climate fluctuations across hundreds of years. Their study, published in Earth and Planetary Science Letters, details how isotopic composition of oxygen in stalagmite formed from calcareous water can aid in climate reconstructions.
The size of tree rings, which can vary by a few millimeters, provides information regarding season precipitation and climatic conditions. The growth zones of stalagmite are a hundred times thinner than a tree ring, meaning a few centimeters can trace the climatic conditions over a thousand years.
In this study, the research team measured the composition of oxygen isotopes with the ion probe at the Institute of Earth Sciences of Heidelberg University. In a cave in southern Germany, researchers collected climate data from the “Kleine Teufelshöhle” stalagmite. They then were able to align the data with global environmental events. For example, 1816 or the “Year Without a Summer” was unusually cold and the stalagmite measurements associated with that time showed that summers were cold and winters were very wet.
Additionally, the study of stalagmite can provide evidence about long-term climate fluctuations. Researchers used their measurements to identify the Little Ice Age and verified their stalagmite data using a tree-ring archive from the same geographic area.
As a result of these findings, scientists no longer have to rely exclusively on tree-ring records to study natural climate fluctuations. Now, stalagmite can serve as a unique archive to accurately reconstruct regional and global climate history.