BP an equilibrium between climate and vegetation was established. BP vegetation probably lagged behind the warming, whereas in the period 8000–4000 cal. BP and/or as climax vegetation in the period 8000–4000 cal. The Holocene Thermal Maximum may be defined several different ways: as temperatures distinctly above modern delimited to 9500–4000 cal. BP when the warm and dry climate of the mid-Holocene changed into the cool, wet and unstable climate of the late Holocene. BP a gradual cooling was initiated, with a more abrupt period of change 4500–3800 cal.
BP when dry climatic conditions became predominant. Precipitation was generally high from 10,000 cal. In contrast to the perceivable variable onset of the main Holocene warm period, maximum temperatures are relatively consistent between the records, indicating temperatures 1.5☐.5☌ above present. Non-analog climatic conditions and lags in vegetation responses to climate change may explain some of the discrepancies seen in the early Holocene between proxies. The sub-regional pattern of climate change suggests a defining influence of the westerlies and the North Cape Current. BP, although many records indicate that the main Holocene warming first occurred about c. An early major warming peaked around 9500 cal. BP), temperatures rose rapidly and were followed by mild, wet and variable conditions. During the earliest part of the Holocene (11,700–10,000 cal. Copyright © 2008 John Wiley & Sons, Ltd.Īn overview of climate reconstructions considering summer air temperatures and effective precipitation is provided for northernmost Fennoscandia. This is in accordance with other regional temperature reconstructions from northern Europe. of 1.5–3☌ above the present during the period of maximum forest expansion, whereas >3☌ above the present temperature at 548 m a.s.l. Reconstruction of the summer temperature indicated mean July temperatures at 400 m a.s.l. Marked climatic deteriorations caused lowering of the forest-lines around 46 cal.
The maximum forest distribution lasted until ca. Alnus incana expanded from 400 to nearly 790 m a.s.l. Local Pinus sylvestris stands are recorded up to 400 m a.s.l. Birch woodland prevailed on the mountain plateau until 3300 cal. and expanded up to near the summit during the next 700 years. Mt Skrubben (848 m a.s.l.), in Dividalen, was deglaciated down to below 280 m a.s.l. Climate change with respect to summer temperature throughout the Holocene is inferred from oscillations in the local Pinus sylvestris, Alnus incana and Betula pubescens forest-lines, as recorded by fossil pollen and plant macrofossils in lake sediments at four altitudinal levels.
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