Abstract: Ensembles of process-based crop models are increasingly used to simulate crop growth for scenarios of temperature and/or precipitation changes corresponding to different projections of atmospheric CO2 concentrations. This approach generates large datasets with thousands of simulated crop yield data. Such datasets potentially provide new information but it is difficult to summarize them in a useful way due to their structural complexities. An associated issue is that it is not straightforward to compare crops and to interpolate the results to alternative climate scenarios not initially included in the simulation protocols. Here we demonstrate that statistical models based on random-coefficient regressions are able to emulate ensembles of process-based crop models. An important advantage of the proposed statistical models is that they can interpolate between temperature levels and between CO2 concentration levels, and can thus be used to calculate temperature and [CO2] thresholds leading to yield loss or yield gain, without rerunning the original complex crop models. Our approach is illustrated with three yield datasets simulated by 19 maize models, 26 wheat models, and 13 rice models. Several statistical models are fitted to these datasets, and are then used to analyze the variability of the yield response to [CO2] and temperature. Based on our results, we show that, for wheat, a [CO2] increase is likely to outweigh the negative effect of a temperature increase of +2 degrees C in the considered sites. Compared to wheat, required levels of [CO2] increase are much higher for maize, and intermediate for rice. For all crops, uncertainties in simulating climate change impacts increase more with temperature than with elevated [CO2].

Abstract: To effectively communicate and disseminate the outputs of CropM and MACSUR per se at national, EU and global levels it is essential that we engage with the appropriate audiences and tailor the level and depth of the outputs accordingly. Consequently for the range of stakeholder outputs there will be a staged period of engagement with stakeholders in the policy and industry sectors (and where appropriate others). This will be driven by the strategies outlined in WP6.3-4 (Strategies for engagement on adaptation and mitigation with national and EU policy makers and with the agro-food chain sector). Once enacted and the feedback collated these response will facilitate the co-construction of an appropriate dissemination strategy. Aligned with this will be a series of standardised dissemination routes that will deliver globally but will then often be followed up by a more local (national) output/dissemination activity tailored for that region. The dissemination strategy will include but will not be limited to multiple and various methods of information distribution including Scientific papers and presentations. Agricultural sector/industry focused talks/presentations and workshops. A fully developed and interactive website (part of the larger project). Social Media Podcasts and WebTV with key actors in the crop and climate change arena including scientists, and stakeholders (policy, agriculturalists and industry representatives). Integration with the cognate EU platforms, e.g. EIP Agricultural and Sustainability, EIT-KIC Climate Change(ETP), the appropriate ETPs (http://cordis.europa.eu/technology-platforms/individual_en.html) and major EU projects such as SUSFOOD etc. No Label