Fig. 2: Spatiotemporal patterns of carbon-water correlation (2001-2018).
From: Recent weakening of carbon-water coupling in northern ecosystems
a Spatial distribution of GPP-ET correlation. Rmean indicates the average of RS GPP-ET correlation values based on the 12 data combinations, with statistical significance marked by ** at p < 0.01. b Spatial trends in RS GPP-ET correlation over the study period. Dot-shaded areas represent regions with significant trends (p < 0.05). The pie chart indicates the proportion of significant (p < 0.05) positive (green) and negative (orange) trends in GPP-ET correlation. c Aggregated mean values of trends along latitudinal gradients, with gray-shaded areas showing the standard deviation among the 12 data combinations. d Spatial distribution of correlation between vegetation indices (EVI, NDVI, LAI, and SIF) and ET. Rmean indicates the spatial average of GPP-ET correlation values, with statistical significance marked by ** at p < 0.01. e Spatial trends in the correlation between vegetation indices (EVI, NDVI, LAI, and SIF) and ET over the study period. Dot-shaded areas represent regions with significant trends (p < 0.05). The pie chart indicates the proportion of significant (p < 0.05) positive (green) and negative (orange) trends. Gray areas indicate non-significant change portions. f Aggregated mean values of trends along latitudinal gradients, with gray-shaded areas showing the standard deviation among the 12 data combinations. g, h Temporal evolution of correlations of RS GPP-ET (g) and vegetation indices and ET (h) from 2001 to 2018, analyzed using a 5-year moving window. The black line represents the ensemble mean of the 12 data combinations, while the gray dashed lines denote individual combinations of remote sensing data.
