Fig. 1

The risk of desiccation increases exponentially with warming. a Physical relationship between saturation vapor pressure (e_s) and air temperature indicates that VPDs are likely to become drier and more variable as climates warm. Blue shading indicates more water required to saturate the air, whereas white indicates less water required for saturation. b Seasonal variation in average nightly temperature and VPD (with standard deviations) from dataloggers during peak times of the year for surface activity in salamanders. Temperature (right axis) is displayed in red and VPD (left axis) is displayed in blue. c, d Non-linear regression analyses with 95% confidence intervals indicated that VPDs (c) and the nightly variation in VPD (d) increase exponentially with warming