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This study focuses on the changes in the yield stability of winter wheat and spring barley over the past 140 years and changes in the weather–yield relationships. The study area is located in the Czech Republic in eastern Central Europe between 48°37′–49°30′N and 15°29′–17°55′E and includes 4900 km2 of arable land within eight districts for which yield data were collected for the years 1869–1913 and 1961–2007. The cropping systems in the region are dominated by rain-fed production of winter wheat, spring barley and winter rape. The yields for winter wheat and spring barley have increased by a factor of 2–3 since the late 19th century, whereas the temperature and precipitation patterns showed trends toward warmer and drier conditions. There was a considerable increase in the inter-annual variability of the absolute yields in the districts. When the variability was evaluated in relative terms (i.e., compared with the yield level), it showed no change or insignificant increases in the warmest and driest regions. The study also found that the sensitivity to inter-seasonal temperature increase was much more pronounced during 1961–2007 than at the end of the 19th century and that an increase of the mean temperature by 1 °C led to yield decreases of up to 11% for winter wheat and up to 10% for spring barley. In contrast, the same temperature increase during the 1869–1913 period would have caused yield decreases of up to 8% and 5%, respectively. In the 1961–2007 period, the negative relationship between the temperature and yields of barley (wheat) was highly significant in seven (eight) of eight districts compared with only four (five) with a much weaker correlation in 1869–1913. During the early period, drier conditions had very small negative or even slightly positive effects on yields, whereas at the end of the 20th century, the May and June drought became a factor that explained a considerable proportion of the yield variability. This was the case especially for spring barley, which is more vulnerable to droughts than is winter wheat. The negative effects of increasing temperature and drought on grain yield were most pronounced in the districts that are currently the warmest and driest. The increasing vulnerability of wheat and barley production to increasing temperatures and droughts over time should be addressed by plant breeders, as there are relatively few adaptation options available to farmers except switching to other crops, which cannot fully substitute for wheat and barley. This study focuses on the changes in the yield stability of winter wheat and spring barley over the past 140 years and changes in the weather–yield relationships. The study area is located in the Czech Republic in eastern Central Europe between 48°37′–49°30′N and 15°29′–17°55′E and includes 4900 km2 of arable land within eight districts for which yield data were collected for the years 1869–1913 and 1961–2007. The cropping systems in the region are dominated by rain-fed production of winter wheat, spring barley and winter rape. The yields for winter wheat and spring barley have increased by a factor of 2–3 since the late 19th century, whereas the temperature and precipitation patterns showed trends toward warmer and drier conditions. There was a considerable increase in the inter-annual variability of the absolute yields in the districts. When the variability was evaluated in relative terms (i.e., compared with the yield level), it showed no change or insignificant increases in the warmest and driest regions. The study also found that the sensitivity to inter-seasonal temperature increase was much more pronounced during 1961–2007 than at the end of the 19th century and that an increase of the mean temperature by 1 °C led to yield decreases of up to 11% for winter wheat and up to 10% for spring barley. In contrast, the same temperature increase during the 1869–1913 period would have caused yield decreases of up to 8% and 5%, respectively. In the 1961–2007 period, the negative relationship between the temperature and yields of barley (wheat) was highly significant in seven (eight) of eight districts compared with only four (five) with a much weaker correlation in 1869–1913. During the early period, drier conditions had very small negative or even slightly positive effects on yields, whereas at the end of the 20th century, the May and June drought became a factor that explained a considerable proportion of the yield variability. This was the case especially for spring barley, which is more vulnerable to droughts than is winter wheat. The negative effects of increasing temperature and drought on grain yield were most pronounced in the districts that are currently the warmest and driest. The increasing vulnerability of wheat and barley production to increasing temperatures and droughts over time should be addressed by plant breeders, as there are relatively few adaptation options available to farmers except switching to other crops, which cannot fully substitute for wheat and barley.

International audience; This study was aimed to develop, test and provide access to a snow cover model for agrometeorological use (snowMAUS) that would rely strictly on the weather data used by all crop simulation models, i.e., diurnal temperature extremes and total daily precipitation. Such snow model can easily be used to preprocess input data in order to account for the presence or absence of snow cover whenever required by the crop modeler, without necessitating the acquisition of additional data. The snow cover model was tested across 65 sites across Austria with considerable variability in elevation (155–3111 m a.s.l.). In addition 7 sites in the Czech Republic were used to evaluate snowMAUS reliability in assessing frost damage to winter wheat crop. For illustration a case study documenting the benefit of coupling snowMAUS with process based crop model (STICS) was also included in the study. The presented work complements previous snow cover modeling studies with its focus on the development of a simple snow cover model for areas under intensive agricultural use (mostly lowlands) with 65% of stations providing weather data being located at altitudes below 800 m. The presented results proved that SnowMAUS can estimate with reasonable precision snow cover presence/absence, and to a large extent snow cover depth. The model also accurately represented seasonal variations in the number of snow days or in the volume of precipitation in the form of snow. The simplicity of the model and the fact that it relies only on the daily data is a great advantage. We have demonstrated that in areas with a high probability of winter temperatures dropping below frost-tolerance thresholds and that tend to have considerable snow cover (e.g., Central Europe), the information about snow cover presence/absence is essential for estimating potential frost damage to winter crops. The snow cover model tested in this study could be easily implemented in most crop growth models and would enhance their performance in the Central European region. The up-to-date version of the model is freely available to users in the scientific community, which should allow for model testing in different climate conditions and application with various types of agrometeorological models