Simulated difference in the mean annual length of the freeze-free season

Simulated difference in the mean annual length of the freeze-free season for the Great Plains region, for the 2041-2070 time period with respect to the reference period of 1980-2000 (left). Color with hatching (category 3) indicates that more than 50% of the models show a statistically significant change in the length of the freeze-free season, and more than 67% agree on the sign of the change (see text). Mean annual length of the freeze-free season for the 1980-2000 reference period (center). Simulated mean annual length of the freeze-free season for the 2041-2070 future time period (right). These are multi-model means from 8 NARCCAP regional climate simulations for the high (A2) emissions scenario. Note that left and right color scales are different. The freeze-freeze season is simulated to become longer throughout the region, with increases mostly in the 20-30 day range.