ИСТИНА

For the last decades, many areas of southern South America have experienced climatic and ecological changes that are driven by global and hemispheric-scale ocean-atmosphere interactions. In order to place these recent changes in a long-term context, and to make them more predictable, we need to explore proxy climate archives extending behind the relatively short instrumental climate records. Tierra del Fuego Island is the southernmost woodland region of the World and is placed close to the Antarctic Peninsula and the Circum-Polar Current, the oceanic factor that controls most of the climate around the Southern Hemisphere. This makes proxy tree-ring data from Tierra del Fuego to be a valuable source of palaeoclimatic information on regional and hemispheric scale. The main objective of this study is to identify long-term climate variability and its extremes in Tierra del Fuego from a tree-ring chronology network covering the insular territory. For this purpose the climatic response of tree ring network consisting of 39 sites of Nothofagus pumilio that was developed in 1980-s, 1990-s and 2000-s was reanalyzed. According to the results the best responding chronologies were updated in the season of 2017/18. In total 13 chronologies were updated up to the ring of 2016 (growing season 2016/17). The updated network covers the period of AD 1648-2016. The results of reanalysis of the updated network showed that it has the best skill in reconstructing climatic parameters of the end of the growing season (February) that depend on maximum and especially minimum temperature (diurnal temperature range, cloudiness, frost day frequency). Also it is important to filter out the persistent 7yrs nonclimatic cycle from tree ring chronologies. Several reconstructions covering last 2-3 centuries are presented and discussed.