Seasonal temperature variability of the Neoglacial (3300-2500Â BP) and Roman Warm Period (2500-1600Â BP) reconstructed from oxygen isotope ratios of limpet shells (Patella vulgata), Northwest Scotland

► We investigated oxygen isotope ratios of archaeological limpet shells. ► Seasonal SST variability was reconstructed across the Neoglacial-RWP transition. ► A cooling climate transition was detected from the Neoglacial to the RWP. ► One Neoglacial specimen captured a year without a summer.