Table 1 Effects of climatic variables on IADFs frequency.

From: Intra-annual density fluctuations in tree rings are proxies of air temperature across Europe

Species

Abbreviation

Total annual precipitation

Mean annual temperature

SPEI

A. unedo

ARUN

+

n.s

E. arborea

ERAR

n.s

+

n.s

L. decidua

LADE

n.s

n.s

n.s

P. abies

PIAB

+

n.s

P. halepensis

PIHA

n.s

+

n.s

P. nigra

PINI

n.s

+

n.s

P. pinaster

PIPI

+

+

+

P. pinea

PIPN

+

+

+

P. sylvestris

PISY

n.s

n.s

n.s

Q. ilex

QUIL

+

n.s

+

Q. robur

QURO

n.s

n.s

n.s

  1. + = positive effect, −  = negative effect, n.s. = not significant. Significance level α < 0.05. All the model coefficients are reported in Supplementary Table 2.