Figure 1. Summary of model performance in predicting high-latitude soil respiration.

Data are shown by algorithm type (a: conditional inference Random Forest, CI-RF; b: ordinary least squares, OLS), level of NDVI detail available to the algorithm (none, and annual, seasonal, monthly, and half-monthly means), and number of years the algorithm was allowed to look into the past. Values given are bin midpoints; out-of-bag R² for CI-RF (see Methods), and adjusted R² for OLS.