2018, Webber, Heidi, Ewert, Frank, Olesen, Jørgen E., Müller, Christoph, Fronzek, Stefan, Ruane, Alex C., Bourgault, Maryse, Martre, Pierre, Ababaei, Behnam, Bindi, Marco, Ferrise, Roberto, Finger, Robert, Fodor, Nándor, Gabaldón-Leal, Clara, Gaiser, Thomas, Jabloun, Mohamed, Kersebaum, Kurt-Christian, Lizaso, Jon I., Lorite, Ignacio J., Manceau, Loic, Moriondo, Marco, Nendel, Claas, Rodríguez, Alfredo, Ruiz-Ramos, Margarita, Semenov, Mikhail A., Siebert, Stefan, Stella, Tommaso, Stratonovitch, Pierre, Trombi, Giacomo, Wallach, Daniel

Understanding the drivers of yield levels under climate change is required to support adaptation planning and respond to changing production risks. This study uses an ensemble of crop models applied on a spatial grid to quantify the contributions of various climatic drivers to past yield variability in grain maize and winter wheat of European cropping systems (1984–2009) and drivers of climate change impacts to 2050. Results reveal that for the current genotypes and mix of irrigated and rainfed production, climate change would lead to yield losses for grain maize and gains for winter wheat. Across Europe, on average heat stress does not increase for either crop in rainfed systems, while drought stress intensifies for maize only. In low-yielding years, drought stress persists as the main driver of losses for both crops, with elevated CO2 offering no yield benefit in these years.

2018, Searchinger, Timothy D., Beringer, Tim, Holtsmark, Bjart, Kammen, Daniel M., Lambin, Eric F., Lucht, Wolfgang, Raven, Peter, van Ypersele, Jean-Pascal

This comment raises concerns regarding the way in which a new European directive, aimed at reaching higher renewable energy targets, treats wood harvested directly for bioenergy use as a carbon-free fuel. The result could consume quantities of wood equal to all Europe’s wood harvests, greatly increase carbon in the air for decades, and set a dangerous global example.