Climate change, impacts and vulnerability in Europe ... - MemoFin.fr

Climate impacts on environmental systemsTable 3.2Habitats and species groups negatively affected by climate change in at least oneEU Member StateHabitat type% of habitatsof this typeaffected byclimate changeTotal numberof habitats ofthis typeSpecies group% of speciesin this groupaffected byclimate changeTotal numberof species inthis groupBogs, mires and fens 50 12 Amphibians 45 51Dunes 29 21 Arthropods 29 118Forests 22 72 Mammals 26 125Heathlands 20 10 Non‐vascular plants 21 38Sclerophyllous scrub 15 13 Molluscs 17 35Coastal 14 28 Reptiles 13 87Rocky habitats 14 14 Fish 4 100Grasslands 10 29 Vascular plants 3 602Freshwater 5 19All habitats 19 218 All species 12 1 158 (*)Note:The table states the proportion of habitat types and species groups listed in the Habitat Directive for which at least oneMember State identified climate change as a reason for unfavourable trends in the area covered or across the natural range.(*) In addition to these species groups, two species from the 'others' (i.e. other groups of animals and plants) category werenoted as affected by climate change: the red coral (Corallium rubrum) and the medicinal leech (Hirudo medicinalis).Source: ETC/BD, 2009.processes and responses. For most cases, only afew years of data are available and do not cover theentire area of the EU but are restricted to certainwell monitored countries with a long tradition inthe involvement of citizen scientists. Based on theseshort time series, the determination of impacts andtheir interpretation thus has to rely on assumptions,and achieving a qualitative understanding of species'responses is more robust than their quantification(Singer and Parmesan, 2010). One of the greatestunknowns is how quickly and closely species willalter their phenology in accordance to a changingclimatic regime (van Asch et al., 2007; Singer andParmesan, 2010). Even experimental studies seemto be of little help, since they notoriously tend tounderestimate the effects of climate change onchanges in phenology (Wolkovich et al., 2012).Observing range shifts (and projecting responsesto climate change) crucially depends on gooddistributional data, which is also better for populargroups of species than for others. There is evidencefrom Denmark and two African regions that birdbiodiversity is a good proxy for total biodiversityin species-rich regions but data from other groupsare needed in less species-rich regions (Larsen et al.,2012). There are large differences in the qualityof observational data, with better data generallyavailable in northern and western Europe than insouthern Europe. Since neither data quality nor lackof data are properly recorded, the true quality ofprojections of range shifts as well as the likelihoodof unobserved range shifts is largely unknown(Rocchini et al., 2011). An extensive meta-analysis ofavailable projections according to different modellingalgorithms, drivers, scenarios, downscalingprocedures or taxonomic identity is also missing(see also Dormann et al., 2008).Species distribution models (also known as habitatmodels, niche models or envelope models) sufferfrom a variety of limitations because species arecurrently not in equilibrium with climate, andbecause species dispersal and biotic interactions arelargely ignored (Bellard et al., 2012; Zarnetske et al.,2012). Furthermore, climate change projections forEurope include climate conditions (in particular insouthern Europe) for which no analogue climatewas available for the model calibration (Pearson andDawson, 2004; Dormann, 2007; Williams and Jackson,2007). Especially the latter problem is evident forprojections for southern Europe since projections ofspecies distribution models lack information fromclimates south of the Mediterranean. Therefore, theuncertainty in the Mediterranean region is muchhigher and projected declines might result from a lackof data from climatic situations not included in themodel.Largely, there are just very coarse methods availablefor incorporating species interactions, populationdynamics and dispersal processes into models ofrange shifts, despite several recent approaches toincorporate these (Pagel and Schurr, 2012; Schweigeret al., 2012).130 Climate change, impacts and vulnerability in Europe 2012