Holocene climate history of the Nunatsiavut (northern Labrador, Canada) established from pollen and dinoflagellate cyst assemblages covering the past 7000years

This study documents the past similar to 7000years of Holocene climatic history for Labrador and Nunatsiavut, using a sedimentary sequence of more than 8m retrieved in Nachvak fjord, one of the northernmost fjords of Nunatsiavut. Using a multi-proxy approach combining a solid Accelerator Mass Spectrometry (AMS)-C-14 chronology and the fossil assemblages of pollen grains and dinoflagellate cysts (dinocysts), we were able to compare terrestrial and marine records in an effort to obtain a better understanding of the mid- to late-Holocene climate history of the Nunatsiavut. Records begin at the end of the deglaciation and showed a general delay in the sequence of climate events which followed, both in terrestrial and marine realms. The presence of Pentapharsodinium dalei in great abundance in Nachvak Fjord revealed a strong influence of the North Atlantic Ocean and the Labrador Sea until similar to 3000yr BP. Afterward, its rather fast disappearance marked the increased influence of Arctic waters. The last 1000years show climate stability in the region over the marine realm and a cooling trend over terrestrial landscapes.