Canopy mortality has doubled in Europe’s temperate forests over the last three decades
Cornelius Senf, Dirk Pflugmacher, Yang Zhiqiang, Julius Sebald, Jan Knorn, Mathias Neumann, Patrick Hostert & Rupert Seidl 
Nature Communications volume 9, Article number: 4978 (2018) 
https://doi.org/10.1038/s41467-018-07539-6