Search results for "Circumpolar star"
showing 6 items of 6 documents
Regional coherency of boreal forest growth defines Arctic driftwood provenancing
2016
Arctic driftwood represents a unique proxy archive at the interface of marine and terrestrial environments. Combined wood anatomical and dendrochronological analyses have been used to detect the origin of driftwood and may allow past timber floating activities, as well as past sea ice and ocean current dynamics to be reconstructed. However, the success of driftwood provenancing studies depends on the length, number, and quality of circumpolar boreal reference chronologies. Here, we introduce a Eurasian-wide high-latitude network of 286 ring width chronologies from the International Tree Ring Data Bank (ITRDB) and 160 additional sites comprising the three main boreal conifers Pinus, Larix, a…
Diverse growth trends and climate responses across Eurasia’s boreal forest
2016
The area covered by boreal forests accounts for similar to 16% of the global and 22% of the Northern Hemisphere landmass. Changes in the productivity and functioning of this circumpolar biome not o ...
Following the Antarctic Circumpolar Current: patterns and processes in the biogeography of the limpet Nacella (Mollusca: Patellogastropoda) across th…
2017
14 pages; International audience; AimWe use an integrative biogeographical approach to further understand the evolution of an important Southern Ocean marine benthic element, the limpet genus Nacella (Mollusca: Patellogastropoda).LocationSouthern Ocean.MethodsWe used multi-locus time-calibrated phylogeny of Nacella at the scale of the whole Southern Ocean to elucidate the underlying processes involved in the origin and diversification of the genus.ResultsDivergence-time estimates suggest that soon after its origin during the mid-Miocene (c. 12.5 Ma), Nacella separated into two main lineages currently distributed in (1) South America and (2) Antarctica and the sub-Antarctic islands. We ident…
Comparative biogeography of echinoids, bivalves and gastropods from the Southern Ocean.
2013
ABSTRACTAim Biogeographical patterns within three classes, the Echinoidea, Bivalvia andGastropoda, were investigated in Antarctic, sub-Antarctic and cold-temperateareas based on species occurrence data. Faunal similarities among regions wereanalysed to: (1) test the robustness of the biogeographical patterns previouslyidentified in bivalves and gastropods; (2) compare them with the biogeographi-cal patterns identified for echinoids; and (3) evaluate the reliability of the bio-geographical provinces previously proposed, depending on the taxa andtaxonomic levels analysed.Location The Southern Ocean, sub-Antarctic islands and cold-temperate areassouth of 45° S latitude at depths of < 1000 m.Meth…
Arctic aerosols and the ‘Divergence Problem’ in dendroclimatology
2021
Considering the importance and complexity of natural (e.g., volcanic eruptions and wildfires) and anthropogenic (e.g., mining, oil and shipping industries) aerosol emissions to Arctic warming is particularly timely given the recent temperature extremes recorded at high-northern latitudes (Cohen et al., 2020; Overland and Wang, 2021). Despite our knowledge about the observed and modelled climatic effects of rising Arctic aerosol concentrations (Schmale et al., 2021), which may exhibit regional and seasonal differences and call for diverse research priorities from local to circumpolar scales, we feel that the ecological consequences of an aerosol-induced reduction in surface irradiance (i.e.,…
Harmonizing circumpolar monitoring of Arctic fox: benefits, opportunities, challenges and recommendations.
2017
Source at http://dx.doi.org/10.1080/17518369.2017.1319602 The biodiversity working group of the Arctic Council has developed pan-Arctic biodiversity monitoring plans to improve our ability to detect, understand and report on long-term change in Arctic biodiversity. The Arctic fox (Vulpes lagopus) was identified as a target of future monitoring because of its circumpolar distribution, ecological importance and reliance on Arctic ecosystems. We provide the first exhaustive survey of contemporary Arctic fox monitoring programmes, describing 34 projects located in eight countries. Monitored populations covered equally the four climate zones of the species’ distribution, and there were large dif…