Abstract: The frequency and intensity of extreme weather is increasing concomitant with changes in the global climate change. Although wheat is the most important food crop in Europe, there is currently no comprehensive empirical information available regarding the sensitivity of European wheat to extreme weather. In this study, we assessed the sensitivity of European wheat yields to extreme weather related to phenology (sowing, heading) in cultivar trials across Europe (latitudes 37.21 degrees to 61.34 degrees and longitudes- 6.02 degrees to 26.24 degrees) during the period 1991-2014. All the observed agro-climatic extremes (>= 31 degrees C, >= 35 degrees C, or drought around heading; >= 35 degrees C from heading to maturity; excessive rainfall; heavy rainfall and low global radiation) led to marked yield penalties in a selected set of European cultivars, whereas few cultivars were found to with no yield penalty in such conditions. There were no European wheat cultivars that responded positively (+ 10%) to drought after sowing, or frost during winter (- 15 degrees C and – 20 degrees C). Positive responses to extremes were often shown by cultivars associated with specific regions, such as good performance under high temperatures by southern-origin cultivars. Consequently, a major future breeding challenge will be to evaluate the potential of combining such cultivar properties with other properties required under different growing conditions with, for example, long day conditions at higher latitudes, when the intensity and frequency of extremes rapidly increase.

Abstract: Europe accounts for around 20% of the global cereal production and is a net exporter of ca. 15% of that production. Increasing global demand for cereals justifies questions as to where and by how much Europe’s production can be increased to meet future global market demands, and how much additional nitrogen (N) crops would require. The latter is important as environmental concern and legislation are equally important as production aims in Europe. Here, we used a country-by-country, bottom-up approach to establish statistical estimates of actual grain yield, and compare these to modelled estimates of potential yields for either irrigated or rainfed conditions. In this way, we identified the yield gaps and the opportunities for increased cereal production for wheat, barley and maize, which represent 90% of the cereals grown in Europe. The combined mean annual yield gap of wheat, barley, maize was 239 Mt, or 42% of the yield potential. The national yield gaps ranged between 10 and 70%, with small gaps in many north-western European countries, and large gaps in eastern and south-western Europe. Yield gaps for rainfed and irrigated maize were consistently lower than those of wheat and barley. If the yield gaps of maize, wheat and barley would be reduced from 42% to 20% of potential yields, this would increase annual cereal production by 128 Mt (39%). Potential for higher cereal production exists predominantly in Eastern Europe, and half of Europe’s potential increase is located in Ukraine, Romania and Poland. Unlocking the identified potential for production growth requires a substantial increase of the crop N uptake of 4.8 Mt. Across Europe, the average N uptake gaps, to achieve 80% of the yield potential, were 87, 77 and 43 kg N ha(-1) for wheat, barley and maize, respectively. Emphasis on increasing the N use efficiency is necessary to minimize the need for additional N inputs. Whether yield gap reduction is desirable and feasible is a matter of balancing Europe’s role in global food security, farm economic objectives and environmental targets.

Abstract: Centre for Regionalchange in the Earth System (CRES, cres-centre.net) is funded by the DanishStrategic Research Council for the period 2009-2014 and is coordinated by theDanish Meteorological Institute. CRES has established a coordinated researcheffort aiming to improve societal preparedness for climate change, inparticular for Denmark. The overall objective of CRES is to extend knowledge ofand reduce the uncertainties surrounding regional climate change and itsimpacts and thereby support future climate change adaptation and mitigationpolicies. Some of the objectives that also have large synergies with theeffects in the CropM theme of MACSUR are a) to reduce uncertainty surroundingregional climate change and its impacts for the period 2020-2050 by improvingmodel formulation and process understanding; b) identify key changes andtipping points in the regional hydrological system, agriculture, freshwater andestuarine ecosystems caused by changes in seasonality, dynamics and extremeevents of precipitation, droughts, heat waves and sea level rise; c) quantifyconfidence and uncertainties in predictions of future regional climate and itsimpacts, by improving the statistical methodology and substance and byintegrating interdisciplinary risk analyses; d) interpret these results inrelation to risk management approaches for climate change adaptation andmitigation. Studies in CRES of particular interest to MACSUR include a)Estimation on generic crop model uncertainties in projection of climate changeimpacts on wheat year, b) Assessment of uncertainties in projected effects onwater balance, crop productivity and nitrate leaching of changes in land use,climate and assessment models.