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Here we assess the quality and in-season development of European wheat (Triticum spp.) yield forecasts during low, medium, and high-yielding years. 440 forecasts were evaluated for 75 wheat forecast years from 1993-2013 for 25 European Union (EU) Member States. By July, years with median yields were accurately forecast with errors below ~2%. Yield forecasts in years with low yields were overestimated by ~10%, while yield forecasts in high-yielding years were underestimated by ~8%. Four-fifths of the lowest yields had a drought or hot driver, a third a wet driver, while a quarter had both. Forecast accuracy of high-yielding years improved gradually during the season, and drought-driven yield reductions were anticipated with lead times of ~2 months. Single, contrasting successive in-season, as well as spatially distant dry and wet extreme synoptic weather systems affected multiple-countries in 2003, ’06, ’07, ’11 and 12’, leading to wheat losses up to 8.1 Mt (>40% of total EU loss). In these years, June forecasts (~ 1-month lead-time) underestimated these impacts by 10.4 to 78.4%. To cope with increasingly unprecedented impacts, near-real-time information fusion needs to underpin operational crop yield forecasting to benefit from improved crop modelling, more detailed and frequent earth observations, and faster computation. [ABSTRACT FROM AUTHOR]

Abstract Each month the JRC issues the MARS Bulletin detailing the agro-meteorological and expert analysis underpinning the assessment of European crops' status and yield forecasts. In this context a resume is provided to give an overview on the geographical distribution of eventual crop damages. The MARS Bulletin provides such information in a set of synthetic maps (Areas of Concern), produced in each Bulletin, depicting extreme weather events and their impact on crops that have occurred in Europe during the analysis period. The present article describes the mix of quantitative and qualitative datasets and methodologies that drive the delineation of the Areas of Concern (AOC) maps and evaluates their capability to resemble crop production losses. The quantitative analysis is based on the Mars Crop Yield Forecasting System (MCYFS) indicators coming from meteorological models, crop growth models and remote sensing data. Indicators are considered in absolute and relative terms and in their relation with standard statistical metrics. The outcome of the quantitative analysis is a set of potential Areas of Concern. Experts' judgment is thus necessary to discriminate potential results through a qualitative analysis focused on: past occurred events and climatologic conditions; agro-management practices; regional agricultural systems peculiarity and their historical resilience and resistance to adverse conditions. In this article the experts' judgment of the team of current MARS analysts, as used in the AOC analysis, is translated into a warning index. Such index condenses the specific contribution to the final production of each development stage and the adverse agrometeorological events occurred, as depicted into the AOC maps. The warning index is computed at country scale for the past five agricultural seasons, from season 2011-2012 to season 2015-2016. Two crops are considered, winter wheat and grain maize as proxy for winter and summer crop groups. The warning indexes calculated are then compared to the national production in a qualitative way. To support the analysis few study cases are presented. The findings of this article highlight that the events depicted in the AOC maps are informative about production losses and specific knowledge is needed to full understand the information carried. Highlights • The comparison of the issued warnings through AOC analysis shows some good agreements with production anomalies. • AOC analysis properly assessed most of the winter wheat production anomalies. • AOC analysis could provide warning relevant at regional scale only. • AOC analysis tends to underestimate unfavorable conditions at harvest. • This paper represents the first attempt to formalize the tacit knowledge within the group of MARS analysts. [ABSTRACT FROM AUTHOR]

Abstract This study describes and evaluates improvements to the MARS crop yield forecasting system (MCYFS) for winter soft wheat (Triticum aestivum) in Europe, based on the WOFOST crop simulation model, by introducing autumn sowing dates, realistic soil moisture initialization, adding vernalization requirements and photoperiodicity, and phenology calibration. Dataset of phenological observations complemented with regional cropping calendars across Europe is used. The calibration of thermal requirements for anthesis and maturity is done by pooling all available observations within European agro-environmental zones and minimizing an objective function that combines the differences between observed and simulated anthesis, maturity and harvest dates. Calibrated phenology results in substantial improvement in simulated dates of anthesis with respect to the original MCYFS simulations. The combined improvements to the system result in a physically more plausible spatial distribution of crop model indicators across Europe. Crop yield indicators point to better agreement with recorded national winter wheat yields with respect to the original MCYFS simulations, most pronounced in central, eastern and southern Europe. However, model skill remains low in large parts of western Europe, which may possibly be attributed to the impacts of wet conditions. Highlights • Improvements to phenological modeling in the MCYFS are proposed. • Field phenological observations are combined with regional cropping calendars in Europe. • Spatial calibration of winter wheat phenology on European level is performed. • Calibrated phenology improved simulated dates of anthesis and potential crop yields. • Further crop model improvements necessary to reproduce observed yield variability. [ABSTRACT FROM AUTHOR]

Abstract: Climate change impacts on potential and rainfed crop yields on the European continent were studied using output of three General Circulation Models and the Crop Growth Monitoring System in combination with a weather generator. Climate change impacts differ per crop type and per CO2 emission scenario. Crops planted in autumn and winter (winter wheat) may benefit from the increasing CO2 concentration. Rainfall is sufficient and if the CO2 concentration increase is high, yields may increase up to 2090. If the CO2 increase is less, increasing temperatures result in declining or stagnating yields after 2050. Crops planted in spring (potato, sugar beet) initially benefit from the CO2 increase, however as time progresses the increasing temperatures reduce these positive effects. By the end of the century yields decline in southern Europe and production may only be possible if enough irrigation water is available. In northern Europe depending on the temperature and CO2 concentration increase, yields either stagnate or decline. However in some of the cooler regions yield increase is still possible. Crops planted in late spring and summer (maize) may suffer from droughts and high temperature in summer. By the end of the century, depending on the temperature rise, crop yields decline almost everywhere. If the temperature increase is less only in north western Europe yields remain stable. [Copyright &y& Elsevier]

Abstract: Recent changes in the simulated potential crop yield and biomass production caused by changes in the temperature and global radiation patterns are examined, using the Crop Growth Monitoring System. The investigated crops are winter wheat, spring barley, maize, winter rapeseed, potato, sugar beet, pulses and sunflower. The period considered is 1976–2005. The research was executed at NUTS2 level. Maize and sugar beet were the crops least affected by changing temperature and global radiation patterns. For the other crops the simulated potential yield remained stable in the majority of regions, while decreasing trends in simulated potential yields prevailed in the remaining regions. The changes appear in a geographical pattern. In Italy and southern central Europe, temperature and radiation change effects are more severe than elsewhere, in these areas potential crop yields of more than three crops significantly decreased. In the UK and some regions in northern Europe the yield potential of various crops increased. In a next step the national yield statistics were analyzed. For a large majority of the countries the yield increases of wheat, barley and to a lesser extent rapeseed are leveling off. Several explanations could be given, however, as the simulated yield potential for these crops decreased in various regions, the changing temperature and radiation patterns may also contribute to the diminishing yield increases or to the stagnation. In more than 50% of the investigated countries the maize, potato and sugar beet yields continue to increase. This can be attributed to improving production techniques, new crop varieties, sometimes in combination with an improving climatic potential. In some regions in northern Europe, yields continue to increase. [ABSTRACT FROM AUTHOR]

Abstract: Recent trends in European seasonal weather conditions and related crop water requirements, crop water consumption and crop water deficits were studied using the Crop Growth Monitoring System of the Joint Research Centre of the European Commission for the period 1976–2005. Soft wheat was selected as a typical winter crop. Sugar beet was selected as a typical spring/summer crop. First we analyzed the spatial and temporal variation of the average seasonal mean temperature and the average seasonal estimated global radiation, subsequently the spatial and temporal variation of the simulated seasonal water requirement, water consumption and water deficit of wheat and sugar beets were studied. We found that the weather pattern changes are not uniformly distributed across Europe. A seasonal dependence was found. The impacts of the changing weather patterns differ per crop and per region. In various European regions the wheat water requirement showed a downward trend which can be attributed to a shorter growing season as a result of higher temperatures in spring. This downward trend can also be attributed to a lower evaporative demand in winter and spring as a result of diminishing global radiation values. Only a limited number of regions showed an upward trend. For sugar beets the Mediterranean regions of France and Spain showed a downward trend in the water requirement which can be attributed to a lower evaporative demand due to reduced solar radiation in summer and autumn. Large areas with an upward trend in the water requirement are spread across the rest of Europe. These upward trends can be attributed to higher temperatures in summer and autumn. The regional trend patterns in actual crop water consumption and water deficit are less distinct than found for the crop water requirements. Changes in these variables can be attributed to the combined effect of variations in crop water requirements and rainfall. [Copyright &y& Elsevier]