Fig. 5.

(A) The influence of temperature on winter ablation differs between lower- and higher-humidity locations, whereas (B) the differences in humidity vary by region. Best-fit lines (P < 0.01) between winter ablation and mean winter temperature for all site years grouped in 0.5 g/m³ absolute humidity bins (A). Mean winter absolute humidity versus winter temperature using site years from the PNW and SW (B). The dark black line represents saturated conditions, whereas the dashed line represents saturated conditions at 0 °C. The dotted line is the empirical at-risk absolute humidity threshold (3.5 g/m³).