Extended Data Fig. 7: Relationship between average lake depth and total heatwave duration from 1970 to 1999.

For each lake thermal region, the relationship between log₁₀[mean lake depth (m)] and the total duration of lake heatwave events per year is shown for the historic period (averaged over all years from 1970 to 1999). The relationships between lake depth and the heatwave metrics (square, not significant: P > 0.001; circle, significant: P < 0.001) were calculated with a generalized additive model (see Methods).