Climate change; new links with the past

An international, multidisciplinary team of researchers have reconstructed Central Europe’s summer climate for the past 2,500 years using tree rings, sub-fossil, archaeological, historical and living tree samples from Germany, France, Italy and Austria. Their findings show how climates and climate change corresponds with events such as the Black Death and the Thirty Years’ War.

The team, led by Willy Tegel (University of Frieburg) and Ulf Büntgen (Swiss Federal Research Institute) have been studying trees, which store information such as natural precipitation rates and temperature fluctuations in order to assess the impact of climate change on society. For instance, the study found that humid and mild summers coincided with the cultural and political growth of Medieval Euope, whereas unfavourable weather conditions coincided with the spread of the Black Death, killing a large percentage of the European population in the 14th Century.

The study also found that “temperature minima in the early 17th and 19th centuries coincided with large-scale settlement abandonment during the Thirty Years’ War and the modern mass migrations from Europe to America.” Overall – the apparent evidence is that throughout the ages, climate has impacted on agrarian wealth, economic growth, disease and society as a whole.

This project has been able to go back much further than any previous study, studying the climate from over 2,000 years ago, yielding new discoveries; “the summer climate during the Roman Era about 2,000 years ago was relatively warm and wet and characterized by less variability. Increased climate variations from around 250-600 A.D. coincided with the demise of the Western Roman Empire and the exceptional turmoil of the Migration Period during which the continent’s population was substantially reordered.”

The authors, however, note that “such comparative studies cannot be used to indicate a direct and simple relationship between climate variability and human history. Their detailed palaeoclimatic history, however, lends new credence to the idea that climate variability can impact human society.”

Published: Friday, 14th January 2011 by Adelle Kehoe