EUROPE'S DROUGHTS ENIGMATIC : RESEARCH

This photo from Sept. 1, 2017, shows Spain on its way to its worst drought in 20 years.
The marshes held less than half of the water they can store, with 47.93% of reserves.
 In Leon, in the north of the country, its main reservoir barely reached 10% at the time.
 Alvaro Fuente / NurPhoto / Getty Images

Paris : Europe's droughts since 2015 ''worst in 2,000 years''. Recent summer droughts in Europe were the most severe the region has seen in 2,110 years as climate change has stoked punishing heat waves, according to new research Monday that raises the alarms for ecosystems and agriculture.

Using data from the rings in living and dead European oaks going back to the time of the Romans, scientists identified a long term drying trend that suddenly intensified in 2015 beyond anything seen in two millennia.

The researchers said that this cluster of abnormally dry summers was likely caused by human-driven climate warming and changes to the circulation of the jet stream.

''Climate change does not mean that it will get drier everywhere: some places may get wetter or colder, but extreme conditions will become more frequent, which could be devastating for agriculture, ecosystems and societies as a whole,'' said lead author Ulf Buntgen, of Cambridge University.

Buntgen, a professor of environmental systems analysis, said the research showed that consecutive summers of intense heat and drought experienced since 2015 is ''extraordinary for central Europe'', in a statement by the University.

To study the timing and severity of historical draughts, researchers analyzed 147 oak trees - including logs pulled out old buildings and archaeological sites and living trees from what is now the Czech Republic and parts of Bavaria - covering a period of 2,110 years.

They then measured the oxygen and carbon isotope composition of 27,080 growth rings, as opposed to the usual tree-ring. measurements in width and density, to plot changes as trees respond to water and heat stress. [AFP]