NEWS RELEASE 21-NOV-2022
Ice Age temperatures and precipitation reconstructed from earthworm granules
New method for determination of past climate data on land applied comparatively for the first time / Ice Age summers in Central Europe were at times warmer than previously known
Peer-Reviewed Publication
JOHANNES GUTENBERG UNIVERSITAET MAINZ
New method for determination of past climate data on land applied comparatively for the first time / Ice Age summers in Central Europe were at times warmer than previously known
Scientists from an international research project led by Johannes Gutenberg University Mainz (JGU) have applied a new method to reconstruct past climate. As they report in the current issue of Communications Earth & Environment, they have determined temperatures and precipitation during the last Ice Age, which peaked about 25,000 years ago, by analyzing earthworm granules. "The new method was discovered at Université Paris 1 Panthéon-Sorbonne and further developed at the Max Planck Institute for Chemistry," said Dr. Peter Fischer of JGU's Institute of Geography, who was the lead investigator of the TerraClime project funded by the German Research Foundation (DFG) in which the study is embedded. "In cooperation with other scientists, including researchers from the University of Lausanne and Römisch-Germanisches Zentralmuseum, we used the method to reconstruct the climate at Schwalbenberg near Remagen and Nußloch near Heidelberg." The two sites form well-developed last-glacial dust deposits. The so-called loess contains sequences dating from 45,000 to 22,000 years before present, in which the earthworm granules with up to about only 2.5 millimeters in size can be found throughout. These calcitic granules, technically known as Earthworm Calcite Granules (ECGs), are secreted daily by earthworms. Using the so-called radiocarbon method, which is based on the decay of the naturally occurring radioactive carbon isotope (14C), researchers can precisely determine their age. Additionally, by analyzing the ratios of stable oxygen and carbon isotopes in the ECGs, it is then possible to reconstruct how warm or how humid it was at the time of their formation.
https://www.eurekalert.org/news-releases/971972
