Stalagmites as Climate Archive

Researchers from Heidelberg and Karlsruhe use stalagmite to reconstruct regional and global climate history. When combined with data from tree-ring records, stalagmites can open up a unique archive to study natural climate fluctuations across hundreds of years, a research team including geoscientists from Heidelberg University and the Karlsruhe Institute of Technology have demonstrated. The researchers analysed the isotopic composition of oxygen in a stalagmite formed from calcareous water in a cave in southern Germany. In conjunction with the data acquired from tree rings, they were able to reconstruct short-term climate fluctuations over centuries and correlate them with historically documented environmental events. Until now, short-term climate fluctuations over hundreds of years could be analysed only by means of tree-ring records by combining independent measurements from a number of studies, explains geoscientist Dr Tobias Kluge of the Karlsruhe Institute of Technology (KIT). The size of the tree rings, which varies by a few millimetres, provides information on the dynamics of seasonal precipitation, in turn pointing to climatic conditions in the specific growth period. According to Dr Kluge, summers with heavy rainfall are expected particularly in cold years, whereas very wet winters are expected in warm years.