Emergence history of the Karelian Isthmus

The Late Weichselian and Holocene emergence history of the Karelian Isthmus and Ladoga Karelia is reasonably well known and the palaeohydrological framework can be worked out, including the chronology of events, which is now entirely based on calibrated radiocarbon dates. Some precisely dated events and morphologically well-developed shorelines form the basis also for archaeological investigations and interpretations. These include the upper limit of the Ancylus transgression, dated at 8100 calendar years BC , the upper limit of the Litorina transgression from 5500 BC in Säkkijärvi to slightly over 5000 BC in Terijoki, and further the drainage of Lake Saimaa to Lake Ladoga at 3700 BC and the upper limit of the Ladoga transgression at 1350 BC, as well as the history and elevations of the ancient Lake Vuoksenlaakso, which terminated as late as in the 19th century

Mielikuvituksellinen Susiluola

Pelkäänpä, että Susiluola liitetään kokoelmaan ennenaikaisesti julkaistuja sensaatiomaisia tutkimustuloksia, jotka ennemmin tai myöhemmin on huomattu liiallisen innon ja mielikuvituksen tuotteiksi

Introduction of agriculture in Valamo, Russian Karelia: palaeoecology of Lake Niikkananlampi

Pioneer results of pollen and charcoal analyses and 14C determinations from Valamo, an island in Lake Ladoga, show some evidence of human activity as long ago as during the Pre-Roman Iron Age (500–0 BC), and indicate that grazing in the area started in the Merovingian Period (AD 550/600–800) and cereal cultivation – in remote parts of the island – in the late 13th century

Millä kielellä yliopistossa opiskellaan?

Turun yliopistoon nimitettiin tammikuussa geologian ja mineralogian professoriksi suomen kieltä taitamaton Ruotsin kansalainen.Oppiaineen toinen professori, myös suomen kieltä taitamaton, on hollantilainen. Hän hoitaa virkatehtävänsä englannin kielellä. Suomenkielisen yliopiston opiskelijat eivät siis saa oppiaineessaan enää lainkaan suomenkielistä professoritason opetusta. Miten voidaan hoitaa yliopistolain velvoittama suomenkielinen opetus kahden kieltä taitamattoman voimin, miten varmistaa opiskelijoiden oikeus tenttiä ja tehdä tutkielmansa omalla äidinkielellään

EU:n tutkimusohjelmien kritiikkiä

Vietin maaliskuun puolivälissä viikon Brysselissä arvioimassa tutkimushakemuksia, jotka liittyvät EU:n V:n puiteohjelman osaohjelmaan 'Global change, climate and biodiversity', tarkemmin sen menneitä ilmastonmuutoksia selvittävään osaan. Kokemus oli kertausta parin vuoden takaisesta.Tutkimuslaitostutkijalle oli virkistävää lukea puhtaita perustutkimushakemuksia, joiden arviointiperustana oli ensi vaiheessa vain tieteellinen taso. Ilahduttavaa oli myös tavata virolaisia tutkijoita samassa työssä osana eurooppalaista perhettä 50 vuotta kestäneen eristyksen jälkeen

Satavuotias Suomalainen Tiedeakatemia

Pääkirjoitu

Biases in radiocarbon dating of organic fractions in sediments from meromictic and seasonally hypoxic lakes

We present here radiocarbon dating results from two boreal lakes in Finland, which are permanently (meromictic) or seasonally stratified and contain continuous sequences of annually laminated sediments that started to form in the early Holocene. The radiocarbon dating results of different organic components were compared with the varve-based sediment chronologies. The deviation between the Lake Valkiajarvi varve chronology (8400 varve years 2-3% error estimate) and 33 C-14 dates taken from insoluble and soluble organic phases vary inconsistently throughout the Holocene. In extreme cases mean calibrated radiocarbon dates with 95.4% confidence levels (2 sigma) are -2350 and +2040 years offset when compared with the varve chronology. On average, the radiocarbon dates are offset by ca. +550 years. The deviation between the Lake Nautajarvi varve chronology (9898 varve years +/- 1% error estimate) and 26 C-14 dates analyzed with conventional and AMS methods indicates that radiocarbon dates are systematically older by 500-1300 years (about 900 years on average). This significant offset mean that radiocarbon dates obtained from organic bulk sediment of meromictic and seasonally hypoxic lakes must be cautiously interpreted because of the reservoir effect and carbon cycling at the sediment-water interface. Direct evidence was obtained from the dating of soluble fraction and insoluble organic matter from near bottom water in the monimolimnion of Lake Valkiajarvi, which yielded C-14 ages of 560 +/- 80 BP and 2070 +/- 140 BP, respectively. Our study reinforces previous results that age-depth models based on bulk sediment radiocarbon dates obtained on sediments of stratified lakes are of limited value for accurate dating of changes in land use and especially the commence of agriculture.Peer reviewe

Climate Variability in Europe and Africa: a PAGES-PEP III Time Stream II Synthesis

The PEP III Europe-Africa transect extends from the arctic fringes of NW Eurasia to South Africa. It encompasses the presently temperate sector of mid-latitude Europe, the Mediterranean region, the arid and semi-arid lands of the Sahara, Sahel and the Arabian Peninsula, and the inter-tropical belt of Africa. The palaeoenvironmental evidence available from these regions, which has been summarised in earlier chapters of this volume and which collectively spans the last 250,000 years, clearly bears the stamp of long-term global climate forcing induced by variations in solar insolation. External forcing is ultimately the reason why the Eurasian continental ice sheets waxed and waned repeatedly during the late Quaternary, and why the southerly limit of permafrost migrated southwards across mid-latitude Europe, periodically becoming degraded during warmer episodes. At the same time, pronounced fluctuations in atmospheric and soil moisture have affected the Mediterranean, desert and Sahel regions, while there is abundant evidence from every sector of the PEP III transect for marked migrations of the principal vegetation belts, as well as for other major environmental changes, that are also considered to reflect long-term climate forcing. It is only in the last decade or so, however, that the full complexity of the history of climate changes during the last interglacial-glacial cycle, and their environmental impacts in continental Europe and Africa, have begun to be recognised. The discovery of evidence for the abrupt Dansgaard-Oeschger (D-O) and Heinrich (H) climatic oscillations in Greenland ice-core (Johnsen et al. 1992) and North Atlantic (Bond et al. 1993) records, have prompted a re-examination of the continental record. This, together with a number of technical improvements in field and laboratory equipment, greater access to sites in remote and difficult terrain, diversification in the range of available palaeoecological and geochronological tools, and closer inter-disciplinary collaboration, have led to a more penetrating examination of the field evidence, which has progressed the science considerably. We can now see that the stratigraphical record is much more complex than appreciated hitherto, and more detailed and refined models of past climatic and environmental models are beginning to emerge. There is, for example, a growing body of evidence which suggests that D-O and H events had significant impacts on the environment of Europe and Africa, as well as on the Mediterranean Sea