Fig. 3.

Climatic debt in community composition shift distances of European breeding birds for (A) all 2,092 communities, (B) communities that did not shift (N = 681), and (C) communities with poor compositional matches (Jaccard dissimilarity > 0.3) suggesting community composition extinctions (N = 140). Color gradient in 50 × 50 km grid cells illustrates the observed difference in distances (km) between temperature isotherm and bird community composition shifts between the 1980s and the 2010s across Europe. Negative values indicate that the community composition has shifted further than expected based on climate change, while positive values indicate a climatic debt. Temperature isotherm shift distance is calculated as the distance from each focal grid cell in the 1980s to the grid cell with the most similar temperature in the 2010s inside a buffer area of 450 km.