Table 1. List of bedrock model outputs from [15] used in the regression.

D = discrete.

Variables	Description	Resolution	Type	Source
r.m1	Median bedrock model	1 km	D	This study
r.srsrq1	Quartile 1 bedrock model	1 km	D	This study
r.srsrq3	Quartile 3 bedrock model	1 km	D	This study