Mid‐ to Late Holocene climate transition and moisture dynamics inferred from South Swedish tree‐ring data

Abstract

A 1561-year tree-ring width (TRW) chronology covering the period 2668-1108 BC (4617-3057 BP) has been developed from 159 moisture-sensitive peatland pines (Pinus sylvestris L.) sampled at Åbuamossen, southern Sweden. Tree population dynamics and annual growth responses of the trees were shown to reflect and give absolute age to regional hydro-climatological changes. The main wet-shifts recorded in the TRW data were precisely dated to 2150-2100, 1550 and 1230-1150 and are likely to be related to the stepwise Mid-to Late Holocene climate transition, during which the condition changed from relatively warm and dry towards cold and moist in the northern hemisphere. The tree-colonization phase was ended by several long-lasting periods showing depressed annual tree growth and an abrupt dying-off phase, possibly caused by increasing water level in the peatland as well as the adjacent river Helge Å. This study demonstrates that TRW data obtained from subfossil peatland trees can provide detailed information and exact age control on moisture variability in peatlands associated with regional hydroclimatic changes. Moreover, the combined information from the stratigraphical and the TRW analyses enabled a detailed temporal and spatial site development reconstruction.

Weiss review of Bradley and Bakke CP-2018-162 northern North Atlantic at 4.2 ka BP

“…Similarly, at Åbuamossen, southern Sweden, a 1561-year tree-ring width chronology was developed from 159 Scots pines. The earliest of three main wet-shifts here is precisely dated 2150-2100 BC, and likely "related to the to the stepwise Mid-to Late Holocene climate transition, during which the condition changed from relatively warm and dry towards cold and moist in the northern hemisphere " (Edvardsson 2016). Synchronous dying off phases during increasingly wet conditions are recorded at Venner Moor, Germany (Eckstein et al, 2010).…”

The Integrated Use of Dendrochronological Data and Paleoecological Records From Northwest European Peatlands and Lakes for Understanding Long-Term Ecological and Climatic Changes—A Review

“…However, in addition to the geographical location, also the stratigraphic context differs between the subfossil pines from southern and northern sites. The subfossil pine material available in southern Fennoscandia that is a couple of thousand years or older comes almost exclusively from peatlands (Edvardsson et al, 2012a,b;Edvardsson, 2016), and similar availability has been noted in the Baltic states (Pukienë, 1997;Edvardsson et al, 2016bEdvardsson et al, , 2018. Moreover, there are examples with pine materials from submerged landscapes in the Baltic Sea (Hansson et al, 2017;Edvardsson et al, 2021).…”

“…In Scandinavia and the Baltic countries, pine represents the most common tree species used for dendrochronological studies based on subfossil trees (Pukienë, 1997;Gunnarson, 1999;Helama et al, 2008;Edvardsson et al, 2012aEdvardsson et al, , 2016b. In central and southern Sweden, peatland pines have been used to develop several multi-millennial tree-ring chronologies (Gunnarson, 1999(Gunnarson, , 2008Edvardsson et al, 2012a,b;Edvardsson, 2016). In northern Finland, subfossil pines from peatlands and lacustrine sediments have been used for decades for dendrochronological studies (Eronen et al, 1999).…”

“…Subfossil oaks have been studied in the reviewed literature (Christensen, 2007;Edvardsson et al, 2014), but not to the same extent as in Germany (Leuschner et al, 2002), Netherlands (Sass-Klaassen and Hanraets, 2006), and Ireland (Brown and Baillie, 2012). The most dominant tree species in the subfossil archives is once again Scots pine (Edvardsson et al, 2012a(Edvardsson et al, ,b, 2014Edvardsson, 2016). However, in addition to the geographical location, also the stratigraphic context differs between the subfossil pines from southern and northern sites.…”

A Rapid Cooling Event Over the Western Pacific Region During the Middle Bronze Age

“…The occurrence of this cold event had a serious impact on the development of human society, and the decline of cities in some parts of Europe has been found to be related to it (e.g., Cretan cities, Siklósy et al., 2007). Meanwhile, the MBACE was in the climate transition stage from the Holocene thermal maximum to the colder late Holocene (∼3,000–4,000 years BP) (Edvardsson, 2016; Morley et al., 2014; Wanner et al., 2008), and the rapid climate transitions during the mid‐to‐late Holocene should be studied intensively because of the very complex mechanisms that occurred, including solar activity fluctuation, volcanic eruption, ocean‐atmosphere interaction, and thermohaline circulation (Wanner et al., 2008). However, due to the lack of high‐resolution climate records and the short duration of ∼300 years of the MBACE, this cooling event has seldom been reported in other places in the world (K. B. Yu et al., 2016), and its details have yet to be explored.…”