An analysis of tree-ring records from Fennoscandia, a region in northern Europe, from the past 1,170 years suggests that the current climate may be substantially warmer than during the medieval period, contrary to previous research. Large uncertainties persist in climate models and proxies at regional scales, particularly prior to AD 1400. Tree-rings can be used to reflect climate change over many centuries and track the amplitude of climate extremes. However, there is currently a discrepancy between tree-ring data and climate models during the medieval climate. Models have suggested it was cooler during this period compared to now, whereas tree-ring data often suggest the opposite. To address this discrepancy and provide a more precise record of the past climate between AD 850 and 2019 in Fennoscandia, researchers analysed 1,170 years of tree ring data, based on around 50 million wood cell measurements from 188 living and dead Scots pine trees. By measuring individual wood cells, called tracheid cells, the researchers were able to collect more accurate data compared to conventional tree-ring data. The authors found that the Fennoscandian climate is substantially warmer today than during the medieval period, supporting the argument that anthropogenic climate change is increasing temperatures in this region.