Journal Article Research Support, Non-U.S. Gov't climate change food security wheat 1.5°C warming 142M471B3J Carbon Dioxide Europe Grain Proteins Multi-model ensemble N762921K75 Nitrogen Research Support, U.S. Gov't, Non-P.H.S. barley climate change adaptation climate change impact crop modeling extreme low yields grain protein impact model ensemble model improvement solanum tuberosum sowing date sowing density super-ensemble tiller mortality tillering uncertainty