Eurasian Arctic Islands

Again, as in the previous section, the best proxy data for this part of the Arctic are to be found in Svalbard. Therefore, the history of the climate for the period analysed will be presented mainly using information from this area. Researchers investigating the history of the climate in the Holocene period (e.g. Tarussov 1992; Werner 1993; Svendsen and Mangerud 1997) generally do not mention the existence of the MWP. Most of them indicate late-Holoccne climatic deterioration (see also Section 10.1), which began around ca. 4000 BP (Werner 1993) or 3000 BP (Tarussov 1992) and persisted to the LIA (Werner 1993) or to the 9,h century (Tarussov 1992). However, there are also some researchers who indicate that the warmer period occurred between A.D. 600 and A.D. 1100 (e.g. Baranowski and Karlcn 1976; Baranowski 1977b; Haggblom 1982; Svendsen and Mangerud 1997). For example, Svendsen and Mangerud (1997), analysing the rate of lake sedimentation (Linnevatnet lake), found that glacial maxima occurred around 2800-2900 BP, 2400-2500 BP. 1500-1600 BP and during the LIA. Thus between these periods warmer conditions prevailed. Baranowski (1977b) even suggested that the MWP probably lasted longer and was warmer than the contemporary warm period. The climate in the transitional period between the MWP and the LIA (i.e. in ihe 12lh century and in the first half of the 13th century) was near the norm (Gordiyenko el al. 1981). From this analysis, and that presented earlier for the Canadian high Arctic, it may be concluded that late-Holocene histories of climate in both study areas are roughly similar. The greatest difference, however, concerns the time of the occurrence and the magnitude of wanning during the MWP. It seems that this period was clearer in the Eurasian Arctic islands than in the Canadian high Arctic and that it occurred earlier, i.e. probably at the same time as it occurred in Greenland.

Proxy data for the LIA period present a clearer climatic picture. In Svalbard, similar to Greenland and the Canadian Arctic, the ice-core results from the Lomonosov ice cap and the GrOnfjord-Fridtjof ice divide distinctly show the existence of the LIA ranging from A.D. 1300-1400 to 1900. This is very well seen both in the isotope record (Figure 10.13) and the summer melt (Figure 10.12(1)). Most of the geomorphological proxy data give the same results. Baranowski (1977b) concluded that the LIA period in Spitsbergen occurred between around 750 and 110 years BP. Similar results for this island are also presented by Punning and Troitskii (1977). The maximum advance of glaciers here occurred about 1600 A.D. and between 1750-1850 A.D. (Ahlmann 1948, 1953). Also the botanical proxy data confirm the existence of the LIA during this time with the culmination between the 17"'and 19th centuries (Surova et al. 1982). Grossvald (1973) found that on Zemlya Frantsa Josifa the LIA began in the 14th century and ended about 1900 A.D. Bazhev and Bazheva (1968) gave very little information concerning the behaviour of glaciers in Novaya Zemlya during the LIA. They stated only that the start of the LIA occurred after the 16,h century.

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