Fig. 6. (a) Spatial distribution of the variation in farm type yield variability (SD, %), and relationships to average temperature (temp, °C) from 1990–2003. Wheat yield variability is similar for different farm types in (b) Champagne-Ardenne, whereas in (c) Emilia-Romagna the diversity in wheat yield variability is larger. In (d) Champagne-Ardenne, standard deviations in the relative wheat yield anomaly for individual years are small (SD = 3.7) and regional yield anomalies (from the trend) are significantly different from zero and correlated to temperature, (r = -0.66 with tempJuly, r = -0.44 with temp). However, in (e) Emilia-Romagna, the standard deviations are large (SD = 8.3) and regional yield anomalies are not significantly different from zero and are not significantly correlated to temperature (r = -0.13 with tempApril, r = 0.33 with temp). Note, temperatures shown in (d) and (e) refer to the months with the largest negative correlation.