title: Uncertainties in the projection of species distributions related to general circulation models.
abstract: Ecological Niche Models (ENMs) are increasingly used by ecologists to project species potential future distribution. However, the application of such models may be challenging, and some caveats have already been identified. While studies have generally shown that projections may be sensitive to the ENM applied or the emission scenario, to name just a few, the sensitivity of ENM-based scenarios to General Circulation Models (GCMs) has been often underappreciated. Here, using a multi-GCM and multi-emission scenario approach, we evaluated the variability in projected distributions under future climate conditions. We modeled the ecological realized niche (sensu Hutchinson) and predicted the baseline distribution of species with contrasting spatial patterns and representative of two major functional groups of European trees: the dwarf birch and the sweet chestnut. Their future distributions were then projected onto future climatic conditions derived from seven GCMs and four emissions scenarios using the new Representative Concentration Pathways (RCPs) developed for the Intergovernmental Panel on Climate Change (IPCC) AR5 report. Uncertainties arising from GCMs and those resulting from emissions scenarios were quantified and compared. Our study reveals that scenarios of future species distribution exhibit broad differences, depending not only on emissions scenarios but also on GCMs. We found that the between-GCM variability was greater than the between-RCP variability for the next decades and both types of variability reached a similar level at the end of this century. Our result highlights that a combined multi-GCM and multi-RCP approach is needed to better consider potential trajectories and uncertainties in future species distributions. In all cases, between-GCM variability increases with the level of warming, and if nothing is done to alleviate global warming, future species spatial distribution may become more and more difficult to anticipate. When future species spatial distributions are examined, we propose to use a large number of GCMs and RCPs to better anticipate potential trajectories and quantify uncertainties.
authors: Laboratoire de Génétique et Evolution des Populations Végétales, UMR 8198 GEPV, Université Lille 1 - Sciences et Technologies (USTL) F-59655, Villeneuve d'Ascq, France ; Laboratoire d'Océanologie et de Géosciences, UMR 8187 LOG, Université Lille 1 - Sciences et Technologies (USTL) 28 Avenue Foch, F-62930, Wimereux, France ; Laboratoire d'Océanologie et de Géosciences, CNRS, UMR 8187 LOG 28 Avenue Foch, F-62930, Wimereux, France.
authors: Eric
authors: E
authors: Goberville
authors: Laboratoire d'Océanologie et de Géosciences, UMR 8187 LOG, Université Lille 1 - Sciences et Technologies (USTL) 28 Avenue Foch, F-62930, Wimereux, France ; Laboratoire d'Océanologie et de Géosciences, CNRS, UMR 8187 LOG 28 Avenue Foch, F-62930, Wimereux, France ; The Laboratory, Sir Alister Hardy Foundation for Ocean Science (SAHFOS) Citadel Hill, Plymouth, PL1 2PB, UK.
authors: Grégory
authors: G
authors: Beaugrand
authors: Laboratoire de Génétique et Evolution des Populations Végétales, UMR 8198 GEPV, Université Lille 1 - Sciences et Technologies (USTL) F-59655, Villeneuve d'Ascq, France.
authors: Nina-Coralie
authors: NC
authors: Hautekèete
authors: Laboratoire de Génétique et Evolution des Populations Végétales, UMR 8198 GEPV, Université Lille 1 - Sciences et Technologies (USTL) F-59655, Villeneuve d'Ascq, France.
authors: Yves
authors: Y
authors: Piquot
authors: Laboratoire d'Océanologie et de Géosciences, CNRS, UMR 8187 LOG 28 Avenue Foch, F-62930, Wimereux, France ; Université d'Artois, ESPE, Centre de Gravelines 40 rue Victor Hugo - BP 129, 59820, Gravelines, France.
authors: Christophe
authors: C
authors: Luczak
keywords: Biogeography; climate change; ecological niche modeling; global change models; species distribution projections; uncertainties