Summary output from the fitted statistical model.

Summary of the model used to describe the influence of surface area (A0), the percent transmission per metre (Iz), altitude above sea level (h), and latitude (φ), as shown in Eq 3, on the diel surface temperature range. EDF is the effective degrees of freedom for the spline representing each covariate. Ref. DF is the reference degrees of freedom used in the statistical test of “no effect” for each smooth. F is the test statistic and p the approximate p-value of the test. Iz is the percent transmission per meter.