title: Greater temperature sensitivity of plant phenology at colder sites: implications for convergence across northern latitudes.
abstract: Warmer temperatures are accelerating the phenology of organisms around the world. Temperature sensitivity of phenology might be greater in colder, higher latitude sites than in warmer regions, in part because small changes in temperature constitute greater relative changes in thermal balance at colder sites. To test this hypothesis, we examined up to 20 years of phenology data for 47 tundra plant species at 18 high-latitude sites along a climatic gradient. Across all species, the timing of leaf emergence and flowering was more sensitive to a given increase in summer temperature at colder than warmer high-latitude locations. A similar pattern was seen over time for the flowering phenology of a widespread species, Cassiope tetragona. These are among the first results highlighting differential phenological responses of plants across a climatic gradient and suggest the possibility of convergence in flowering times and therefore an increase in gene flow across latitudes as the climate warms.
authors.affiliation: WSL Institute for Snow and Avalanche Research SLF, 7260 Davos, Switzerland.|USDA-Forest Service, Pacific Northwest Research Station, Olympia, WA 98512, USA.
authors.forename: Janet
authors.initials: J
authors.lastname: Prevéy
authors.affiliation: Département de Biologie, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada.
authors.forename: Mark
authors.initials: M
authors.lastname: Vellend
authors.affiliation: German Centre for Integrative Biodiversity Research (iDiv), 04103 Leipzig, Germany.|Smithsonian Tropical Research Institute, Balboa Ancón, Panama, Republic of Panama.
authors.forename: Nadja
authors.initials: N
authors.lastname: Rüger
authors.affiliation: Biology Department, Grand Valley State University, Allendale, MI 49041, USA.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Hollister
authors.affiliation: German Centre for Integrative Biodiversity Research (iDiv), 04103 Leipzig, Germany.|School of Geosciences, University of Edinburgh, Edinburgh, UK.
authors.forename: Anne D
authors.initials: AD
authors.lastname: Bjorkman
authors.affiliation: School of Geosciences, University of Edinburgh, Edinburgh, UK.
authors.forename: Isla H
authors.initials: IH
authors.lastname: Myers-Smith
authors.affiliation: National Ecological Observatory Network, Boulder, CO, USA.
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Elmendorf
authors.affiliation: Environment and Natural Resources, Government of the Northwest Territories, NT X1A 3S8, Canada.
authors.forename: Karin
authors.initials: K
authors.lastname: Clark
authors.affiliation: Institute for Arctic and Marine Biology, UiT-The Arctic University of Norway, 9037 Tromsø, Norway.
authors.forename: Elisabeth J
authors.initials: EJ
authors.lastname: Cooper
authors.affiliation: Center for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, DK-1350 Copenhagen, Denmark.
authors.forename: Bo
authors.initials: B
authors.lastname: Elberling
authors.affiliation: Faroese Museum of Natural History, Hoyvík 188, Faroe Islands.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Fosaa
authors.affiliation: Department of Geography and Biodiversity Research Institute, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Gregory H R
authors.initials: GHR
authors.lastname: Henry
authors.affiliation: Arctic Research Center, Department of Bioscience, Aarhus University, DK-8000 Aarhus, Denmark.
authors.forename: Toke T
authors.initials: TT
authors.lastname: Høye
authors.affiliation: The University Centre in Svalbard, N-9171 Longyearbyen, Norway.|Faculty of Life and Environmental Sciences, University of Iceland, 101 Reykjavík, Iceland.
authors.forename: Ingibjörg S
authors.initials: IS
authors.lastname: Jónsdóttir
authors.affiliation: Department of Ecology and Natural Resources, Norwegian University of Life Sciences, NO-1432, Ås, Norway.
authors.forename: Kari
authors.initials: K
authors.lastname: Klanderud
authors.affiliation: Université du Québec à Trois-Rivières, Trois-Rivières, QC G9A 5H7, Canada.
authors.forename: Esther
authors.initials: E
authors.lastname: Lévesque
authors.affiliation: Center for Ecosystem Science and Society Center, Northern Arizona University, Flagstaff, AZ 86011, USA.
authors.forename: Marguerite
authors.initials: M
authors.lastname: Mauritz
authors.affiliation: Department of Biology and Environmental Sciences, University of Gothenburg, S-405 30 Gothenburg, Sweden.
authors.forename: Ulf
authors.initials: U
authors.lastname: Molau
authors.affiliation: Woods Hole Research Center, Falmouth, MA 02540, USA.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Natali
authors.affiliation: Department of Biological Sciences, Florida International University, Miami, FL 33181, USA.
authors.forename: Steven F
authors.initials: SF
authors.lastname: Oberbauer
authors.affiliation: Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada.
authors.forename: Zoe A
authors.initials: ZA
authors.lastname: Panchen
authors.affiliation: Department of Wildlife, Fish, & Conservation Biology, University of California, Davis, CA 95616, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Post
authors.affiliation: Department of Botany and Biodiversity Research, University of Vienna, A-1030 Vienna, Austria.
authors.forename: Sabine B
authors.initials: SB
authors.lastname: Rumpf
authors.affiliation: Arctic Research Center, Department of Bioscience, Aarhus University, DK-8000 Aarhus, Denmark.
authors.forename: Niels M
authors.initials: NM
authors.lastname: Schmidt
authors.affiliation: Center for Ecosystem Science and Society Center, Northern Arizona University, Flagstaff, AZ 86011, USA.
authors.forename: Edward A G
authors.initials: EAG
authors.lastname: Schuur
authors.affiliation: Institute for Arctic and Marine Biology, UiT-The Arctic University of Norway, 9037 Tromsø, Norway.
authors.forename: Phillip R
authors.initials: PR
authors.lastname: Semenchuk
authors.affiliation: Woods Hole Research Center, Falmouth, MA 02540, USA.
authors.forename: Tiffany
authors.initials: T
authors.lastname: Troxler
authors.affiliation: Department of Biological Sciences, University of Alaska, Anchorage, AK 99508, USA.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Welker
authors.affiliation: WSL Institute for Snow and Avalanche Research SLF, 7260 Davos, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Rixen
mesh_terms: D057231:Climate Change; D003080:Cold Temperature; D063245:Plant Development; D012621:Seasons; D013696:Temperature; D065929:Tundra
keywords: 
  Cassiope tetragona
  ; Arctic; International Tundra Experiment; climate change; climatic gradient; flowering; latitude; tundra