Shrubs tracing sea surface temperature—Calluna vulgaris on the Faroe Islands

Abstract

The climate of Central and Northern Europe is highly influenced by the North Atlantic Ocean due to heat transfer from lower latitudes. Detailed knowledge about spatio-temporal variability of sea surface temperature (SST) in that region is thus of high interest for climate and environmental research. Because of the close relations between ocean and coastal climate and the climate sensitivity of plant growth, annual rings of woody plants in coastal regions might be used as a proxy for SST. We show here for the first time the proxy potential of the common and widespread evergreen dwarf shrub Calluna vulgaris (heather), using the Faroe Islands as our case study. Despite its small and irregular ring structure, the species seems suitable for dendroecological investigations. Ring width showed high and significant correlations with summer and winter air temperatures and SST. The C. vulgaris chronology from the Faroe Islands, placed directly within the North Atlantic Current, clearly reflects variations in summer SSTs over an area between Iceland and Scotland. Utilising shrubs like C. vulgaris as easy accessible and annually resolved proxies offers an interesting possibility for reconstruction of the coupled climate-ocean system at high latitudes.

Changes in the Content of Some Groups of Phenolic Compounds and Biological Activity of Extracts of Various Parts of Heather (Calluna vulgaris (L.) Hull) at Different Growth Stages

“…and the monotypic genus Calluna Salisb. [1]. Heather is a relict evergreen dwarf shrub and widely distributed in Europe.…”

Influence of climatic conditions on growth rings of Salix uva-ursi Pursh from the southeastern shore of Hudson Bay, Subarctic Canada

“…These factors can be substantial drivers of the "greening" of the tundra, mainly associated to the expansion of shrub species. The importance of soil moisture and the role of atmospheric precipitation have been previously observed for willows from the Svalbard Archipelago in the High Arctic (Owczarek and Opała 2016;Opała-Owczarek et al 2018) and Siberia (Blok et al 2011) but was often ignored in studies focusing only on the influence of summer temperature (Weijers, Broekman, and Rozema 2010;Buchwał et al 2013;Beil et al 2015). For temperature, the highest correlation coefficients were obtained with the sum of maximum temperatures above 5°C from May to August.…”

Growth form and leaf habit drive contrasting effects of Arctic amplification in long‐lived woody species

“…Such pervasive response to SST from Arctic shrub species have never been reported except for a study by Beil et al (2015), though performed over a much shorter period, on Calluna vulgaris in the Faroe Islands; crossdating issues, a focus on the year-to-year variability, and the lack of long enough chronologies, likely prevented the detection of a similar outcome (Myers-Smith, Elmendorf, et al, 2015. Nonetheless, in Iceland, we highlighted a substantial difference between growth form adaptation strategies in coping with the increasing temperature pattern.…”