The coldest decade of the millennium?
While searching through historical archives to find out more about the 15th-century climate of what is now Belgium, northern France, Luxembourg, and the Netherlands, Chantal Camenisch noticed something odd. "I realised that there was something extraordinary going on regarding the climate during the 1430s," says the historian from the University of Bern in Switzerland.
She joined forces with Kathrin Keller, a climate modeller at the Oeschger Centre for Climate Change Research in Bern, and other researchers, to find out more about the 1430s climate and how it impacted societies in northwestern and central Europe. Their results are published in Climate of the Past, a journal of the European Geosciences Union.
|Historical documents describing the impacts of the 1430s extraordinary climate|
[Credit: Zurich, Staatsarchiv]
There have been other cold periods in Europe's history. In 1815, the volcano Mount Tambora spewed large quantities of ash and particles into the atmosphere, blocking enough sunlight to significantly reduce temperatures in Europe and other parts of the world. But the 1430s were different, not only in what caused the cooling but also because they hadn't been studied in detail until now.
|Lake sediments from lake Oeschinen, Switzerland [Credit: Benjamin Amann, University of Bern]|
Regardless of the underlying causes of the odd climate, the 1430s were "a cruel period" for those who lived through those years, says Camenisch. "Due to this cluster of extremely cold winters with low temperatures lasting until April and May, the growing grain was damaged, as well as the vineyards and other agricultural production. Therefore, there were considerable harvest failures in many places in northwestern and central Europe. These harvest failures led to rising food prices and consequently subsistence crisis and famine.
|Microscopic view of laminated sediments from Lake Oeschinen, Switzerland |
[Credit: Benjamin Amann, University of Bern]
|Microscopic view of laminated sediments from Lake Zabinskje in Poland |
[Credit: Christoph Butz, University of Bern]
Keller says another decade of very cold winters could happen again. "However, such temperature variations have to be seen in the context of the state of the climate system. Compared to the 15th century we live in a distinctly warmer world. As a consequence, we are affected by climate extremes in a different way -- cold extremes are less cold, hot extremes are even hotter."
|Finding clues to Earth's past climate in stalagmites |
[Credit: Adam Hasenfratz]
"Our example of a climate-induced challenge to society shows the need to prepare for extreme climate conditions that might be coming sooner or later," says Camenisch. "It also shows that, to avoid similar or even larger crises to that of the 1430s, societies today need to take measures to avoid dangerous anthropogenic climate interference."
Source: European Geosciences Union [December 01, 2016]