Data from: Increase in CO2 concentration could alter the response of Hedera helix to climate change

• Increasing CO2 concentrations ([CO2]) is likely to affect future species
distributions, in interaction with other climate change drivers. However,
current modelling approaches still seldom consider interactions between
climatic factors and the importance of these interactions therefore
remains mostly unexplored. • Here, we combined dendrochronological and
modelling approaches to study the interactive effects of increasing [CO2]
and temperature on the distribution of one of the main European liana
species, Hedera helix. We combined a classical continent-wide species
distribution modelling approach with a case study using H. helix and
Quercus cerris tree rings, where we explored the long term influence of a
variety of climate drivers, including increasing [CO2], and their
interactions, on secondary growth. Finally, we explored how our findings
could influence the model predictions. • Climate-only model predictions
showed a small decrease in habitat suitability for H. helix in Europe,
however this was accompanied by a strong shift in the distribution toward
the north and east. Our growth ring data suggested that H. helix can
benefit from high [CO2] under warm conditions, more than its tree hosts,
which showed a weaker response to [CO2] coupled with higher cavitation
risk under high temperature. Increasing [CO2] might therefore offset the
negative effects of high temperatures on H. helix and we illustrate how
this might translate into maintenance of H. helix in warmer areas. Our
results highlight the need to consider carbon fertilization and
interactions between climate variables in ecological modelling. Combining
dendrochronological analyses with spatial distribution modelling may
provide opportunities to refine predictions of how climate change will
affect species distributions.