6533b884fe1ef96bd12de5a3

RESEARCH PRODUCT

Buffering of forest temperatures across the globe

subject

description

Climate change is affecting the phenology, distribution and performance of species across the globe. Yet, especially for species living in the shade of trees, lags in vegetation and animal responses have been reported. This effect might be attributed to tree canopies that buffer the temperature at the forest floor. However, we do not know how much understorey temperatures deviate from the macroclimate across the globe. A global analysis quantifying forest floor temperatures is lacking. Here we quantify temperature differences between forests and open areas, only retaining data from studies with a strict paired design: microclimate was quantified below trees vs macroclimate in the open. By compiling >50 independent studies from across five continents, we find that on average, forest-floor temperatures are buffered by c. 1.6 °C. Maximal temperatures are buffered much more (cooler by > 4 °C) than minimum temperatures (even warmer in the forest understorey, by c. 1 °C). We also find that the buffering capacity (decoupling) increases at warmer open-habitat temperatures. Such knowledge is key to better predict forest biodiversity and ecosystem responses to climate change. peerReviewed