title: Atlantic SSTs control regime shifts in forest fire activity of Northern Scandinavia.
abstract: Understanding the drivers of the boreal forest fire activity is challenging due to the complexity of the interactions driving fire regimes. We analyzed drivers of forest fire activity in Northern Scandinavia (above 60 N) by combining modern and proxy data over the Holocene. The results suggest that the cold climate in northern Scandinavia was generally characterized by dry conditions favourable to periods of regionally increased fire activity. We propose that the cold conditions over the northern North Atlantic, associated with low SSTs, expansion of sea ice cover, and the southward shift in the position of the subpolar gyre, redirect southward the precipitation over Scandinavia, associated with the westerlies. This dynamics strengthens high pressure systems over Scandinavia and results in increased regional fire activity. Our study reveals a previously undocumented teleconnection between large scale climate and ocean dynamics over the North Atlantic and regional boreal forest fire activity in Northern Scandinavia. Consistency of the pattern observed annually through millennium scales suggests that a strong link between Atlantic SST and fire activity on multiple temporal scales over the entire Holocene is relevant for understanding future fire activity across the European boreal zone.
authors.affiliation: Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, P.O. Box 49, 230 53 Alnarp Sweden.|Chaire industrielle CRSNG-UQAT-UQAM en aménagement forestier durable, Université du Québec en Abitibi-Témiscamingue (UQAT), 445 boul. de l'Université, Rouyn-Noranda, Québec, J9×5E4, Canada.
authors.forename: Igor
authors.initials: I
authors.lastname: Drobyshev
authors.affiliation: Chaire industrielle CRSNG-UQAT-UQAM en aménagement forestier durable, Université du Québec en Abitibi-Témiscamingue (UQAT), 445 boul. de l'Université, Rouyn-Noranda, Québec, J9×5E4, Canada.
authors.forename: Yves
authors.initials: Y
authors.lastname: Bergeron
authors.affiliation: GEOTOP, Université du Québec à Montréal, CP 8888, Montréal, Québec, H3C3P8, Canada.
authors.forename: Anne de
authors.initials: Ad
authors.lastname: Vernal
authors.affiliation: Department of Physical Geography, Stockholm University, Svante Arrhenius väg 8, 106 91 Stockholm, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Moberg
authors.affiliation: Centre for Bio-Archeology and Ecology (UMR5059CNRS), Université Montpellier 2, 163 rue Auguste Broussonet, F-34090 Montpellier, France.
authors.forename: Adam A
authors.initials: AA
authors.lastname: Ali
authors.affiliation: Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, P.O. Box 49, 230 53 Alnarp Sweden.
authors.forename: Mats
authors.initials: M
authors.lastname: Niklasson