Fig. 3.
(A) Relationships between the average SPEI time-scales at which the maximum SPEI/GIMMS-NDVI correlation is found and the average annual water balance across eco-regions considering separately negative and positive water balances. (B) Relationship between the average SPEI time-scale at which maximum SPEI/tree-ring correlation is found and the average annual water balance across eco-regions. (C) Relationship between the average SPEI time-scale at which maximum SPEI/ANPP correlation is found and the average annual water balance across eco-regions for negative and positive water balances. Error bars represent ±1/2 SDs. The linear fits and the coefficients of determination are also shown in all graphs. See corresponding colors in the legend of Fig. 2.