New data extracted from the glaciers of Greenland, suggest that the concentration of methane in the atmosphere follows the rise and decline of civilizations.

A study undertaken by the international team, showed that people began to produce a significant amount of this powerful greenhouse gas long before the industrial revolution - even in the times of the Roman Empire and the Han dynasty.

Fluctuations in the atmospheric concentration of methane caused by changes in agriculture, technological progress, political and social history. For example, to clear the land under cultivation actively forests, wood and coal were widely used for heating of houses and churches, as well as metal smelting. All this led to the release of methane in such volumes that can be tracked.

The analysis of gas bubbles contained in the ice cores, allows to reconstruct the composition of the atmosphere in different periods of history. In the case of methane can even figure out where it came from, because it can be not only a product of human labour, but also the vital functions of plants and animals, volcanic activity and fires.

However, nothing can tell scientists were natural or man-made fires, but then came to help the global reconstruction of land-use last two millennia. The results showed that 20-30% of methane released to the atmosphere as a result of fires from 100 B.C. in 1600, it is of anthropogenic origin.

At the final graphs researchers saw the effects not only of the medieval climate optimum and the little ice age, but also active release of methane in periods of prosperity in the Mediterranean during the Roman Empire and China during the Han dynasty, its subsequent decline and new growth as the recovery of Europe in the middle ages and the Renaissance. Even the Black Death has left its mark in the annals so serious test it was.

But still, nothing compares with the surge that began with the industrial revolution.

The study is published in the journal Nature.

Based on the materials of the Federal Polytechnic school of Lausanne.