Integrating timescales : A palaeoclimatological perspective on 4.2 ka event in the Baltic | Sammanfläta tidskalor : Ett paleoklimatologiskt perspektiv på 4,2 ka event:et i östersjöområdet

The Baltic Sea region is a key region in monitoring environmental challenges in the face of contemporary climate change. By using societal responses to climate change in the deep and near past as a reservoir of knowledge, it can inspire future policy. An established, ratified global event, dealing with both climate and society, the 4.2 ka event, has not received much attention in the Baltic. This thesis looks at the role of palaeoclimatology in an integrative, cross-disciplinary approach using a human ecodynamics framework. Simultaneously, a regional perspective on the impacts of the 4.2 ka event is provided. The instrumental record produced by climate reconstruction methods reflects real climate variability in different ways. By uncovering these internal assumptions and the time-sensitivity of palaeoclimatological methods, I demonstrate the potential and limitations of synthesising different proxies in a multi-site compilation. Through the open-data repository LiPDverse, terrestrial records indicative of temperature and precipitation around the 4.2 ka event from Baltic are sourced. The Baltic Sea region observes a general cooling during the 4.2 ka event, with spatially dependent effects on hydroclimate, the north and west experience drying, while signals from the southeast more mixed (indicating stable, drying or wetter conditions). For future human ecodynamics scholarship, the potential integration of this compiled regional climate archive is contrasted with the previous transfer of palaeoclimatological knowledge into archaeology from the Baltic Sea region. To enable cross-disciplinary synthesis, methodological constraints and evidentiary should be highlighted to ensure a proper transfer of knowledge. The changes around 4200 BP in the Baltic are not reflecting the magnitude defined in the event on the Geologic Time Scale. However, the region remains a complex system of climatic and societal change at this time. The study still shows the potential of combing archaeology and paleoclimatology within an ecodynamics framework.